Skip to main content
Research Article
Originally Published 15 June 2016
Free Access

Cost-Effectiveness of Percutaneous Closure of the Left Atrial Appendage in Atrial Fibrillation Based on Results From PROTECT AF Versus PREVAIL

Circulation: Arrhythmia and Electrophysiology

Abstract

Background—

Randomized trials of left atrial appendage (LAA) closure with the Watchman device have shown varying results, and its cost effectiveness compared with anticoagulation has not been evaluated using all available contemporary trial data.

Methods and Results—

We used a Markov decision model to estimate lifetime quality-adjusted survival, costs, and cost effectiveness of LAA closure with Watchman, compared directly with warfarin and indirectly with dabigatran, using data from the long-term (mean 3.8 year) follow-up of Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation (PROTECT AF) and Prospective Randomized Evaluation of the Watchman LAA Closure Device in Patients With Atrial Fibrillation (PREVAIL) randomized trials. Using data from PROTECT AF, the incremental cost-effectiveness ratios compared with warfarin and dabigatran were $20 486 and $23 422 per quality-adjusted life year, respectively. Using data from PREVAIL, LAA closure was dominated by warfarin and dabigatran, meaning that it was less effective (8.44, 8.54, and 8.59 quality-adjusted life years, respectively) and more costly. At a willingness-to-pay threshold of $50 000 per quality-adjusted life year, LAA closure was cost effective 90% and 9% of the time under PROTECT AF and PREVAIL assumptions, respectively. These results were sensitive to the rates of ischemic stroke and intracranial hemorrhage for LAA closure and medical anticoagulation.

Conclusions—

Using data from the PROTECT AF trial, LAA closure with the Watchman device was cost effective; using PREVAIL trial data, Watchman was more costly and less effective than warfarin and dabigatran. PROTECT AF enrolled more patients and has substantially longer follow-up time, allowing greater statistical certainty with the cost-effectiveness results. However, longer-term trial results and postmarketing surveillance of major adverse events will be vital to determining the value of the Watchman in clinical practice.

WHAT IS KNOWN

Randomized trials of left atrial appendage (LAA) closure with the Watchman device have shown varying results, and its cost-effectiveness compared to anticoagulation has not been evaluated using all available contemporary trial data.

WHAT THE STUDY ADDS

Using data from the PROTECT AF trial, LAA closure with the Watchman device was cost-effective.
Using PREVAIL trial data, Watchman was more costly and less effective than warfarin and dabigatran.
PROTECT AF enrolled more patients and has substantially longer follow-up time, allowing greater statistical certainty with the cost-effectiveness results, but longer term trial results and postmarketing surveillance of major adverse events will be vital to determining the value of the Watchman in clinical practice.
Nonvalvular atrial fibrillation (AF) currently affects between 2 and 4 million people in the United States, and the prevalence is increasing.1,2 AF causes ischemic stroke, and long-term anticoagulation with warfarin or the target-specific oral anticoagulants can safely reduce the risk of ischemic stroke.38 Device-based alternatives to anticoagulation that attempt to exclude the left atrial appendage (LAA) from the systemic circulation have been developed.915 The Watchman device (Boston Scientific, Plymouth, MN), a catheter-based, self-expanding LAA occluding device, has been studied in 2 relatively small randomized trials against warfarin.1618 The results of these trials were disparate, resulting in significant uncertainty in the clinical community about the value of this new treatment paradigm. This uncertainty was reflected in a protracted US Food and Drug Administration evaluation of the Watchman device that ultimately resulted in approval in March 2015.
See Editorial by Pokorney and Mark
The Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation (PROTECT AF) study was an international trial of 707 subjects with AF and a CHADS2 score ≥1 who were randomly assigned to LAA occlusion with the Watchman device and planned warfarin discontinuation or warfarin therapy.16 At a mean follow-up of 18 months, LAA occlusion was noninferior to warfarin for the composite end point of stroke, systemic embolism, or cardiovascular death.16 At a mean follow-up of 3.8 years, patients in the device group had a significantly lower risk of the same composite end point and the independent end points of stroke or systemic embolism, cardiovascular mortality, and all-cause mortality.18 However, there was a substantial rate of periprocedural complications, including stroke and pericardial effusion, and implant failure.16
Prospective Randomized Evaluation of the Watchman LAA Closure Device in Patients With Atrial Fibrillation (PREVAIL) was a confirmatory, US-based trial that randomly assigned 407 patients to LAA occlusion with Watchman or warfarin.17 The patients in this study had somewhat higher risk for stroke than those in PROTECT AF with a higher mean age (74 versus 72 years in the device group), higher CHADS2 score (2.6 versus 2.2), and higher rate of previous stroke or transient ischemic attack (27.5% versus 17.7%). At 18 months, the rates of the composite end point of stroke, systemic embolism, and cardiovascular mortality were similar (0.064 in the device group versus 0.063 in the control group), but the device did not achieve the prespecified criteria for noninferiority because of large 95% confidence intervals. Periprocedural safety events with LAA closure were substantially lower in PREVAIL than in PROTECT AF. However, the rates of intracranial hemorrhage (ICH) and major extracranial hemorrhage were substantially higher in the device arm of the study.
The primary cost-effectiveness study on LAA closure to date showed that the technology may be cost effective but used only the 18-month PROTECT AF data for model assumptions and a Canadian healthcare system payer perspective.19 A follow-up analysis incorporating longer-term PROTECT AF data similarly demonstrated that LAA closure may be cost effective relative to medical anticoagulation, but this study excluded the conflicting data from PREVAIL.20 We evaluated the quality-adjusted survival, costs, and cost effectiveness of the Watchman device for LAA closure compared with warfarin using the most contemporary clinical trial data and a US payer perspective. Given the divergent results of PROTECT AF and PREVAIL with respect to safety and efficacy, and the marked difference in follow-up (3.8-year average follow-up versus 18 months), we did not perform meta-analysis or pooling of underlying data inputs but rather presented our cost-effectiveness estimates for the 2 trials separately. In addition, given that the healthcare landscape now includes the alternative to treat AF patients with the target-specific oral anticoagulants, we compared LAA closure and warfarin to dabigatran as a broadly representative agent in this new class of drugs.

Methods

Decision Model

We used a Markov model21 to perform a decision analysis comparing 3 treatment strategies for the prevention of thromboembolism in patients with AF: adjusted-dose warfarin with a target international normalized ratio of 2.0 to 3.0, dabigatran 150 mg twice daily, and LAA closure with planned discontinuation of anticoagulation. Our base case consisted of a hypothetical cohort of patients aged 70 years with AF at increased risk for stroke (ie, CHADS2 score ≥1) and no contraindications to anticoagulation.
Most health states in the model have been previously described22 and included healthy with AF, reversible ischemic neurological deficit, ischemic stroke (mild or moderate to severe), ICH (mild or moderate to severe), combined stroke and ICH, myocardial infarction (MI), systemic embolism, and death (Figure 1).4 We applied utilities and costs to each outcome in 2-week increments during its expected duration and discounted costs and benefits at 3% per year.23
Figure 1. Decision model. The schematic at the top represents the treatment arms: warfarin, dabigatran, and percutaneous closure of the left atrial appendage (LAA). M represents a Markov process with 10 health states for each of the treatment options. These potential health states (and transitions) are identical for each of the treatment options. All patients remain in the Well state until one of the 5 events occur: transient ischemic attack (TIA), stroke, intracranial hemorrhage (ICH), systemic embolism, myocardial infarction, extracranial hemorrhage, or death. The probabilities of these events depend on the prescribed therapy. The triangles on the right indicate which health state the patient enters after an event. Reversible ischemic neurological event (RIND) is the health state that patients enter after a TIA or a stroke without residual deficit. Mild represents a neurological event that results in a neurological deficit but no limitation performing activities of daily living, whereas Moderate to Severe represents a neurological event that results in loss of independence for at least 1 activity of daily living. This figure does not show the perioperative events associated with the LAA closure, but these events occur before the Markov nodes and are enumerated in Table 1 under the section Periprocedural adverse events, LAA closure.
For LAA occlusion, we created 2 sets of model inputs, based on PROTECT AF and PREVAIL, and compared both sets of model results to those of warfarin and dabigatran treatment. Risks for adverse events included in our model were generally derived from the event rates published in the PROTECT AF, PREVAIL, and RE-LY (Randomized Evaluation of Long-Term Anticoagulation Therapy; trial of dabigatran versus warfarin) trials unless stated otherwise.4,5,17,18 Because PROTECT AF data have been published in several iterations, we used the periprocedural complication rates from the index publication16 and long-term event dates from the most recent publication based on mean 3.8-year follow-up data.18 For values not available in the published literature, we identified adverse event rates from the Food and Drug Administration filing.24 For conditions not included in our model, such as cancer, we assumed that event rates were similar across all treatments. For each treatment, we quantified quality-adjusted survival, adverse event risk, and net costs to age 100 years or until death (whichever occurred earlier). Model building and analyses were performed using TreeAge Pro Suite (TreeAge Software, Williamstown, MA) and Microsoft Excel (Microsoft, Redmond, WA).

Probability of Adverse Outcomes in the Decision Model

Treatment Assumptions

In PROTECT AF, the occlusion device was implanted in 408 of 449 patients (88%) in whom it was attempted. Patients for whom device implantation was unsuccessful were treated with warfarin. For patients assigned to the device arm of PROTECT AF, we assumed that clinical adverse events could occur in the periprocedural period or during the long-term period thereafter. In PROTECT AF, for the first 45 days after device placement, patients were maintained on warfarin anticoagulation and aspirin 81 to 325 mg daily. Eighty-six percent of patients were then transitioned to clopidogrel 75 mg daily and aspirin for day 45 until 6 months, but 14% were maintained on warfarin and aspirin until 6 months because of incomplete appendage closure, based on blood flow around the device demonstrated on transesophageal echocardiography. After 6 months, 92% patients who had successful LAA closure were transitioned to aspirin therapy only, and the remaining 8% were maintained on warfarin indefinitely because of incomplete appendage closure.
In PREVAIL, the LAA closure device was implanted in 252 of 265 patients (95%) in whom it was attempted. The same medication treatment paradigms were used in PREVAIL and PROTECT AF as specified by the trial protocols. Ninety-two percent of patients were then transitioned to clopidogrel 75 mg daily and aspirin 81 to 325 mg daily for day 45 until 6 months, but 8% were maintained on warfarin until 6 months because of incomplete appendage closure, based on blood flow around the device demonstrated on transesophageal echocardiography. After 6 months, 99% of patients who had successful LAA closure were transitioned to aspirin therapy only, and the remaining 1% was maintained on warfarin indefinitely because of incomplete appendage closure.
Mortality rates were adjusted for age (beginning at age 70 years). The presence of AF and antithrombotic therapy were accounted for in our model by the clinical event rates of the intention-to-treat analyses of PROTECT AF, PREVAIL and RE-LY.3,4,18,2529

Periprocedural Adverse Events

The PROTECT AF model assumed that in the periprocedural period after LAA closure, 1.5% of patients had a serious pericardial effusion, 1.1% of patients had an ischemic stroke, 0.6% of patients had a device embolization, and 0.2% had an esophageal tear.16 The PREVAIL model assumed that in the periprocedural period after LAA closure, 0.4% of patients had a serious pericardial effusion, 0.7% of patients had an ischemic stroke, 0.7% of patients had a device embolization, and 0.2% had an esophageal tear.17

Ischemic Stroke

In the PROTECT AF base case, the annual rate of ischemic stroke was 1.1% per year for warfarin, and the relative risk for ischemic stroke with dabigatran was 0.76 compared with warfarin.4,5,16,18,30 In the PREVAIL base case, the annual rate of ischemic stroke was 0.7% per year for warfarin.17 For LAA closure, the long-term annual rate of ischemic stroke (excluding periprocedural events) was 1.4% per year in PROTECT AF and 1.9% per year in PREVAIL (Table 1).17,18,30 In the base case, we assumed that ischemic strokes after LAA closure resulted in discontinuation of aspirin therapy and replacement with warfarin.
Table 1. Base Case Values and Ranges Used in Sensitivity Analyses*
VariablesPROTECT AF Base Case Value (Range)PREVAIL Base Case Value (Range)Reference
Stroke
Annual rate of ischemic stroke,%
 Warfarin1.1 (0.5–1.7)0.7 (0–3.9)16–18,30
 Dabigatran, relative risk vs warfarin0.76 (0.6–0.98)0.76 (0.6–0.98)4,5
 Aspirin3.2 (2.0–5.0)3.2 (2.0–5.0)25,31–33
 LAA closure1.1 (0.7–1.7)1.1 (0.2–3.2)16–18,30
Ischemic strokes with all therapies, %
 Fatal (within 30 d)8.2 (8.2–10.1)8.2 (8.2–10.1)3,33–41
 Major (nonfatal)40.2 (40.2–41.7)40.2 (40.2–41.7)3,33–41
 Minor42.5 (34.8–42.5)42.5 (34.8–42.5)3,33–41
 No residual9.1 (9.1–13.3)9.1 (9.1–13.3)3,33–41
Hemorrhage
Annual rate of ICH, %
 Warfarin1.1 (0.5–1.8)0 (0–3.7)16–18,30,42–44
 Dabigatran, relative risk vs warfarin0.41 (0.28–0.60)0.41 (0.28–0.60)4,5
 LAA closure0.2 (0–0.4)0.4 (0–2.2)16–18,30
Annual rate of major hemorrhage excluding ICH
 Warfarin2.0 (1.2–3.2)2.1 (0.4–5.4)16,18,24,37,44–47
 Dabigatran, relative risk vs warfarin1.07 (0.94–1.21)1.07 (0.94–1.21)4,5
 LAA closure1.3 (0.8–2.0)4.2 (2.1–7.5)16,18,24
Myocardial infarction
Annual rate of myocardial infarction, %
 Warfarin0.64 (0.4–0.9)0.64 (0.4–0.9)4,5
 Dabigatran, relative risk vs warfarin1.27 (0.94–1.71)1.27 (0.94–1.71)4,5
 LAA closure0.9 (0.5–1.4)0.9 (0.5–1.4)4
Systemic embolism
Annual rate of systemic embolism, %
   
 Warfarin0 (0–3.7)0 (0–3.7)4,5,17,18,30
 Dabigatran, relative risk vs warfarin0.75 (0.60–0.90)0.75 (0.60–0.90)4,5
 LAA closure0.2 (0–0.4)0.4 (0–2.2)17,18,30
Mortality
Relative risk reduction0.66 (0.45–0.98)1.017,18
Periprocedural adverse events, LAA closure
Rate of adverse event, % per procedure
 Ischemic stroke1.1 (0.4–2.6)0.7 (0–3.9)16,17
 Serious pericardial effusion1.5 (0.6–3.1)0.4 (0–3.6)16,17
 Device embolization0.6 (0.1–1.2)0.7 (0.1–2.5)16,17
 Esophageal tear0.2 (0–1.1)0.2 (0–1.1)16
 Age at start of 30-y interval, y70 (65–100)70 (65–100)Assumption
Quality-of-life estimates (utility)
Healthy
 Warfarin0.987 (0.953–1.0)48
 Dabigatran0.994 (0.975–1.0)29
 Aspirin0.998 (0.994–1.0)48
 LAA closure0.998 (0.994–0.996)48
Neurological event with residua
 Mild0.75 (0–1.0)48
 Moderate to severe0.39 (0–1.0)48
 Recurrent0.12 (0–1.0)48
Myocardial infarction0.84 (0–1.0)49
Systemic embolism0.73 (0–1.0)49
Temporary states, days of perfect health lost
 Major hemorrhage other than ICH3 (0–5)50,51
 Serious pericardial effusion5 (0–10))52
 Device embolization15 (0–30)52
 Esophageal tear5 (0–10)52
Costs
Daily cost of medication, $
 Warfarin (not including INR monitoring)0.16 (0.10–1.5)53
 Dabigatran4.86 (3–10)5,53
 Aspirin0.02 (0.005–0.20)53
 Plavix0.35 (0.25–1.5)53
 Cost of INR laboratory, $6.15 (4–10)54
 Cost of LAA closure with imaging, $24 011.22 (10 000–30 000)12,55, estimate
One-time cost of ischemic neurological event
 Moderate to severe20 719.26 (12 000–27 000)29,55–58
 Mild14 857.85 (7000–20 000)29,55–58
 Transient ischemic attack or RIND6453.44 (3000–12 000)29,55–58
One-time cost of ICH16 427.67 (10 000–65 000)29,55–58
Monthly cost of ischemic neurological event
 Moderate to severe5716 (3000–9000)29,55–60
 Mild2400 (1000–4000)29,55–60
Monthly cost of ICH
Moderate to severe5716 (3000–10 000)29,55–59,61
Mild2400 (1000–4000)29,55–60
Monthly cost of ischemic neurological event and ICH6800 (3000–13 000)29,55–60
One-time cost of myocardial infarction20 016.33 (15 000–25 000)55
Monthly cost of myocardial infarction325 (125–580)62
One-time cost of systemic embolism27 558.82 (15 000–35 000)55
Monthly cost of systemic embolism2389 (1000–5000)63,64
Other one-time costs
 Major hemorrhage9164.43 (5000–15 000)55
 Serious pericardial effusion22 092.86 (10 000–30 000)55
 Device embolization57 006.20 (35 000–70 000)55
 Esophageal tear11 095.22 (5000–35 000)55
Cost discounting rate, %3 (0–5)21
ICH indicates intracranial hemorrhage; INR, international normalized ratio; LAA, left atrial appendage; NVAF, nonvalvular atrial fibrillation; PREVAIL, Prospective Randomized Evaluation of the Watchman LAA Closure Device in Patients With Atrial Fibrillation; PROTECT AF, Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation; and RIND, reversible ischemic neurological deficit.
*
Costs are in 2014 US Dollars.

Intracranial Hemorrhage

For the base case, the annual rate of ICH was 1.1% per year in PROTECT AF and 0% in PREVAIL on warfarin.17,18,30 The relative risk for ICH on dabigatran was 0.26 compared with warfarin (0.4% per year), based on RE-LY.4,5,16 The rate of ICH after LAA closure was 0.2% per year in PROTECT AF and 0.4% per year in PREVAIL.17,18,30

Stroke and Hemorrhage Severity

We classified initial ischemic stroke into 4 categories: fatal, moderate-to-severe neurological sequelae, mild neurological sequelae, and no residual neurological deficit.3,29,3341 We assumed that a second mild ischemic stroke resulted in a moderate-to-severe ischemic stroke. We classified hemorrhage into 4 categories: fatal, ICH with moderate-to-severe neurological sequelae, ICH with mild neurological sequelae, and nonfatal extracerebral major hemorrhage.4,31,37,4247

Quality-of-Life Estimates

We calculated quality-adjusted survival by multiplying the probabilities of adverse events by quality-of-life estimates (utilities).48 We adjusted baseline quality of life for age.49 We obtained the utility for warfarin without complications from published data on patients with AF that were based on patient ratings of their quality of life while receiving warfarin, including prothrombin time monitoring and changes in diet or lifestyle. The mean utility was 0.987 for warfarin29,48 and 0.998 for aspirin.29,48
We estimated the utility for dabigatran as 0.994 as in previous studies,22 which was derived from a survey of anticoagulation physicians for an older direct thrombin inhibitor, ximelagatran.4,5,29
We accounted for the temporary decrease in quality of life associated with the LAA closure procedure by reducing quality of life by 30% for 10 days. After 10 days, patients were assigned the utility for warfarin while on that medication and the utility for aspirin thereafter.48
Any ischemic or hemorrhagic neurological event with residual deficit, MI, and systemic embolism were associated with permanent decreases in quality of life. We assigned temporary decrements in quality of life (utility) for ischemic stroke with no residual neurological deficit, transient ischemic attack, nonfatal extracerebral major hemorrhage, pericardial effusion, esophageal tear, and device embolization.

Costs

Costs, expressed in 2014 US Dollars, reflected the perspective of an ideal insurer that covered inpatient and outpatient medical care and prescription costs. For each treatment, we projected costs >35 years; future costs and life years were discounted at 3% per year. We included age-adjusted average healthcare expenditures for each patient and then added the costs associated with the 3 treatment strategies.65 This analysis excluded indirect costs.

Drug Treatment Costs

We estimated medication costs for warfarin, dabigatran, and aspirin based on the median consumer prices in the United States.53,66 For warfarin anticoagulation, we combined the annual medication cost with the cost for 14 international normalized ratio tests and the Center for Medicare and Medicaid Services (CMS) reimbursement for a period of 90 days of anticoagulation management (Current Procedural Terminology code 99364). In sensitivity analyses, we allowed for patients initiating warfarin to have ≤8 additional international normalized ratio tests and for CMS reimbursement to be at the higher rate allowed for anticoagulation initiation for a 90-day period (Current Procedural Terminology code 99363).12,67

LAA Closure Costs

The Watchman device was recently approved by the Food and Drug Administration, and the CMS made a final determination to cover LAA closure on February 8, 2016 under diagnosis-related group (DRG) 273 (percutaneous intracardiac procedure with major complication or comorbidity) at a rate of $20 961 and DRG 274 (percutaneous intracardiac procedure without major complication or comorbidity) at a rate of $14 288. Because the device is only indicated in patients with AF and a CHADS2 score ≥2 or a CHA2DS2-VASc score ≥3, we estimated that the great majority of procedures will be reimbursed at the higher rate. We also included the cost of 1 transesophageal echocardiogram at the time of the procedure and physician fee reimbursement, for a total cost of $24 010.55,68
Ancillary costs of imaging and clinical follow-up were modeled according to the PROTECT AF trial protocol, including transesophageal echocardiography at 45 days, 6 months, and 12 months after implantation and 4 established care outpatient physician visits.16

Adverse Event Costs

We estimated the one-time costs of ischemic stroke, transient ischemic attack, ICH, and MI based on the costs of a hospitalization for the DRG or the International Classification of Diseases, Ninth Revision code published by the Agency for Healthcare Research and Quality (AHRQ) HCUPnet.55 We estimated monthly costs of care for each of these complications based on previously published cost estimates using CMS reimbursement for the DRG, adjusted to 2014 US dollars using the gross domestic product deflator.29,5658,62,6971 We estimated the one-time cost of a major extracranial hemorrhage based on the hospital cost for the International Classification of Diseases, Ninth Revision codes associated with gastrointestinal hemorrhage (530.21, 578.1, 578.9, and 772.4) published by AHRQ HCUPnet. We estimated the acute care costs of systemic embolization based on costs for the International Classification of Diseases, Ninth Revision code 444.09 (Other arterial embolism and thrombosis of abdominal aorta). We estimated monthly costs of care for patients after systemic embolization based on previously published cost estimates using CMS reimbursement for the DRG, adjusted to 2014 US Dollars using the gross domestic product deflator.28,5460 We estimated the one-time costs of a serious pericardial effusion based on the hospital costs for the International Classification of Diseases, Ninth Revision codes 423.0 and 423.3 published by AHRQ HCUPnet. We estimated the one-time costs of an esophageal tear using the hospital cost for DRG 368 (major esophageal disorder) published by AHRQ HCUPnet.

Sensitivity Analyses

We performed 1-way sensitivity analyses of the variables in the decision model over their plausible ranges (Table 1). Ranges for clinical events were derived from 95% confidence intervals for event rates from the PROTECT AF, PREVAIL, and RE-LY trials, as well as other published literature.4,16,17,24,30 When 95% confidence intervals were not published, a Poisson distribution was assumed to calculate the confidence interval. Medication costs for aspirin, warfarin, and dabigatran included the range of discount and retail costs.53
We conducted a sensitivity analysis in which we varied the baseline risk of ischemic stroke or ICH for all 3 treatment strategies by the same ratio to simulate the cost-effectiveness ratios for patients at varying risk for these adverse events (eg, low to high CHADS2).
Because procedural success and safety can be considerably worse with inexperienced operators outside of clinical trials, we also conducted a sensitivity analysis in which we decreased the rate of successful device implantation and increased the rates of each of the periprocedural adverse events from those reported in PROTECT AF and assessed how this impacted the cost effectiveness of the device.

Probabilistic Sensitivity Analysis

Probabilistic sensitivity analysis takes into account all sources of uncertainty in the data inputs and generates a best estimate of which therapy is preferred at different cost-effectiveness thresholds. We performed second-order Monte Carlo simulations,22,72 randomly sampling (with replacement) a distribution of all variables 10 000 times and then simulating outcomes. For event rates, we generally used a normal distribution, except for the mutually exclusive subcategorization of stroke, for which we used a Dirichlet distribution. We used a beta distribution for utilities and a gamma distribution for costs.

Results

Base Case Analyses

Under base case conditions with mean 3.8-year follow-up data from PROTECT AF, the quality-adjusted life expectancy was 7.96 quality-adjusted life years (QALYs) with warfarin, 8.28 QALYs with dabigatran, and 9.94 QALYs with LAA closure (Table 2; Figure I in the Data Supplement). Total costs were $92 190 for warfarin, $94 072 for dabigatran, and $132 844 for LAA closure. Comparing LAA closure with warfarin, the incremental cost-effectiveness ratio (ICER) was $20 486 per QALY, and comparing LAA closure with dabigatran, the ICER was $23 422 per QALY. In a base case cohort of 10 000 patients followed over their lifetime, LAA closure was associated with an ischemic stroke rate lower than warfarin and similar to that of dabigatran, and it was associated with a markedly lower rate of ICH compared with both anticoagulants (Table 3). LAA closure and dabigatran were also associated with higher rates of MI than warfarin.
Table 2. Projected Costs and QALYs for Patients With Nonvalvular Atrial Fibrillation for PROTECT AF and PREVAIL*
Annual Stroke and ICH Rate With Warfarin, %TherapyCost, $QALYsMarginal Cost per QALY for LAA Closure vs Dabigatran, $Marginal Cost per QALY for LAA Closure vs Warfarin, $
Base case trial
 PROTECT AFWarfarin92 1907.96  
 Dabigatran94 0728.28  
 LAA closure132 8449.9423 42220 486
 PREVAILWarfarin73 0778.54  
 Dabigatran83 7468.59  
 LAA closure120 9778.44DominatedDominated
ICH indicates intracranial hemorrhage; LAA, left atrial appendage; PREVAIL, Prospective Randomized Evaluation of the Watchman LAA Closure Device in Patients With Atrial Fibrillation; PROTECT AF, Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation; and QALY, quality-adjusted life year.
*
Costs are in 2014 US dollars. QALYs in the table are rounded values, but marginal costs per QALY were calculated using nonrounded data.
Table 3. Major Adverse Events for a Hypothetical Cohort of 10 000 Patients With AF Treated With Each Therapy and Followed Over Their Lifetime Starting at Age 70 Years
Trial Data SourceTherapyIschemic StrokeIntracranial HemorrhageMyocardial Infarction
PROTECT AFWarfarin17861234762
 Dabigatran1557592949
 LAA closure17032921311
PREVAILWarfarin1332105799
 Dabigatran1187104977
 LAA closure13624721062
AF indicates atrial fibrillation; LAA, left atrial appendage; PREVAIL, Prospective Randomized Evaluation of the Watchman LAA Closure Device in Patients With Atrial Fibrillation; and PROTECT AF, Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation.
Using data from PREVAIL for the base case data inputs, the quality-adjusted life expectancy was 8.54 QALYs with warfarin, 8.59 QALYs with dabigatran, and 8.44 QALYs with LAA closure (Table 2; Figure II in the Data Supplement). Total costs were $73 077 for warfarin, $83 746 for dabigatran, and $120 977 for LAA closure. LAA closure was dominated by both warfarin and dabigatran, meaning that it was both less effective (lower QALYs) and more costly than both medical alternatives. In a base case cohort of 10 000 patients followed over their lifetime, LAA closure was associated with an ischemic stroke rate similar to warfarin and higher than dabigatran and a markedly higher rate of ICH (Table 3).

Sensitivity Analyses

One-way sensitivity analyses for the comparison of LAA closure to warfarin showed that the cost effectiveness of LAA closure was most sensitive to changes in the rates of stroke and ICH (Figures III and IV in the Data Supplement). The model was also sensitive to the cost of the Watchman, the utility with warfarin, the cost of stroke, the rate of systemic embolism, the cost of ICH, and the rate of MI, and the utility associated with major adverse events (stroke, ICH, and MI). Using the PROTECT AF data inputs, the cost-effectiveness estimates were only moderately sensitive to these parameters, and the ICER for LAA closure compared with both medical therapies remained below $35 000 per QALY for all values of each variable tested. Using PREVAIL data inputs, the cost-effectiveness estimates were insensitive to these parameters, and the ICER for LAA closure compared with both medical therapies remained above $100 000 per QALY for all value ranges of each variable tested.

Ischemic Stroke

The cost effectiveness of LAA closure could be sensitive to changes in ischemic stroke rates for patients with LAA closure. Using data from PROTECT AF, 1-way sensitivity analysis on the rate of stroke after LAA closure over the plausible range from the trial showed that the ICER of LAA closure remained below $50 000 per QALY in comparison to both warfarin and dabigatran (Figure 2). Using data from PREVAIL, if the long-term rate of stroke with LAA closure dropped below 0.6 strokes per 100 person-years, LAA closure would no longer be dominated, but the ICER of LAA closure would remain above $100 000 per QALY even if the long-term stroke rate dropped as low as 0.2 per 100 person-years (Figure 3).
Figure 2. One-way sensitivity analysis showing the effect of varying the long-term ischemic stroke rate of percutaneous closure of the left atrial appendage (LAA) on the incremental cost effectiveness of LAA closure compared with warfarin and dabigatran in PROTECT AF. The incremental cost-effectiveness ratio of LAA closure remained below $50 000 per quality-adjusted life year in comparison to both warfarin and dabigatran across the range of stroke rates. The vertical dotted line shows the base case. PROTECT AF indicates Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation.
Figure 3. One-way sensitivity analysis showing the effect of varying the long-term ischemic stroke rate of percutaneous closure of the left atrial appendage (LAA) on the incremental cost effectiveness of LAA closure compared with warfarin and dabigatran in PREVAIL. If the long-term rate of stroke with LAA closure dropped below 0.6 strokes per 100 person-years, LAA closure would no longer be dominated, but the incremental cost-effectiveness ratio of LAA closure would remain above $100 000 per quality-adjusted life year across the range of stroke rates. The vertical dotted line shows the base case. PREVAIL indicates Prospective Randomized Evaluation of the Watchman LAA Closure Device in Patients With Atrial Fibrillation.

Intracranial Hemorrhage

The cost effectiveness of LAA closure could be sensitive to changes in ICH rates for patients with LAA closure (Figures V and VI in the Data Supplement). Using data from PROTECT AF, 1-way sensitivity analysis on the rate of ICH after LAA closure over the plausible range from the trial showed that the ICER of LAA closure remained below $30 000 per QALY in comparison to both warfarin and dabigatran. Using data from PREVAIL, if the rate of ICH with LAA closure dropped below 0.1% ICHs per 100 person-years, LAA closure would no longer be dominated but the ICER would remain above $500 000 per QALY for both warfarin and dabigatran.

Periprocedural Adverse Events and Less Experienced Operator Sensitivity Analysis

One-way sensitivity analyses showed that the model was insensitive (incremental cost effectiveness varied by <$1000 per QALY) to each of the periprocedural adverse events, including pericardial effusion, ischemic stroke, device embolization, and esophageal tear.
To test the possible effect of less experienced operators performing LAA closure, we decreased the rate of successful device implantation to 80% and increased each of the periprocedural adverse event rates to the highest value in their plausible ranges. For this scenario, using data from PROTECT AF, the ICER for LAA closure was $29 090 per QALY compared with warfarin and $35 360 per QALY compared with dabigatran. For this scenario, using data from PREVAIL, LAA closure remained dominated compared with warfarin and dabigatran, meaning that it was both less effective (lower QALYs) and more costly than both medical alternatives.

Probabilistic Sensitivity Analysis

In the Monte Carlo simulation, varying all data inputs simultaneously based on data from PROTECT AF, warfarin was most likely to be cost effective at a willingness-to-pay threshold <$6000 per QALY, dabigatran was most likely to be cost effective between $6000 and $21 000 per QALY, and LAA closure was most likely to be cost effective above that. LAA closure was 89% and 98% likely to be cost effective at willingness-to-pay thresholds of $50 000 and $100 000, respectively (Figure 4). Using data from PREVAIL, warfarin was most likely to be cost effective at all willingness-to-pay thresholds. Percutaneous closure of the LAA was 9% and 14% likely to be cost effective at willingness-to-pay thresholds of $50 000 and $100 000 per QALY, respectively (Figure 5). We generated scatter plots including all the values from these simulations for both trials, which showed relatively modest variability around our base case estimates of cost and quality-adjusted survival (Figures VII and VIII in the Data Supplement).
Figure 4. Cost-effectiveness acceptability curves representing the probability that each treatment strategy is cost effective for a given willingness-to-pay threshold per quality-adjusted life year (QALY) gained in PROTECT AF. Warfarin was most likely to be cost effective at a willingness-to-pay threshold <$6000/QALY, dabigatran was most likely to be cost effective between $6000 and $21 000 per QALY, and left atrial appendage (LAA) closure was most likely to be cost effective above that. LAA closure was 89% and 98% likely to be cost effective at willingness-to-pay thresholds of $50 000 and $100 000, respectively. PROTECT AF indicates Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation.
Figure 5. Cost-effectiveness acceptability curves representing the probability that each treatment strategy is cost effective for a given willingness-to-pay threshold per quality-adjusted life year (QALY) gained in PREVAIL. Warfarin is most likely to be cost effective at all willingness-to-pay thresholds. Percutaneous closure of the left atrial appendage (LAA) was 9% and 14% likely to be cost effective at willingness-to-pay thresholds of $50 000 and $100 000 per QALY, respectively. PREVAIL indicates Prospective Randomized Evaluation of the Watchman LAA Closure Device in Patients With Atrial Fibrillation.

Discussion

We found that in patients aged 70 years with AF at an increased risk of stroke (CHADS2 score ≥1), compared with oral anticoagulation, the quality-adjusted survival and cost effectiveness of LAA closure with the Watchman device varied considerably based on which clinical trial was used for the base case data inputs and assumptions. Using long-term follow-up (mean: 3.8 years) data inputs from PROTECT AF, the ICER of LAA closure compared with warfarin was $20 486 per QALY. However, using the 18-month follow-up data inputs from PREVAIL, LAA closure had lower quality-adjusted survival and was more costly (dominated in cost-effectiveness terms). At a willingness-to-pay threshold of $50 000 per QALY, LAA closure was cost effective 89% of the time under PROTECT AF assumptions and 9% of the time under PREVAIL assumptions. These results were sensitive to the rates of ischemic stroke and ICH for LAA closure and medical anticoagulation, and it was the marked variation in these rates across the trials that accounted for most of the variation in the effectiveness (quality-adjusted survival) and cost effectiveness of the different treatment modalities. These findings indicate that the cost effectiveness of LAA closure will critically depend on whether rates of adverse events such as stroke and ICH in typical clinical practice mirror those of the clinical trials and demonstrate the critical need for systematic postmarket surveillance of LAA closure.
Our results using longer-term follow-up data from PROTECT AF extend the results of a previous cost-effectiveness analysis using 18-month follow-up data from PROTECT AF and modeled in the Canadian healthcare system.19 That study showed an ICER of $41 565 per QALY for LAA closure compared with warfarin. During the 3.8-year follow-up of the PROTECT AF study, the rates of ischemic stroke and bleeding were very favorable for LAA closure relative to medical anticoagulation, leading to better quality-adjusted survival and cost effectiveness. The rate of ICH with LAA closure in particular was dramatically lower than with medical anticoagulation. During the extended time frame of our base case model, the cumulative effect of ongoing higher relative risk of major adverse events, particularly bleeding, with medical anticoagulation outweighed the early risk of periprocedural adverse events with LAA closure, resulting in a low ICER of $20 486 per QALY compared with warfarin.
In contrast, during the 18-month follow-up of the PREVAIL study, LAA closure was associated with similar or higher rates of ischemic stroke compared with medical anticoagulation and higher rates of ICH, leading to lower quality-adjusted survival and poor cost effectiveness. This was driven, in large part, by the substantially lower risk of stroke and ICH in the warfarin arm of PREVAIL. Importantly, these adverse event rates for warfarin were markedly lower than that in PROTECT AF and in the control arms of several recent studies evaluating the novel anticoagulants (Table I in the Data Supplement).4,68 In addition, if the trends in long-term bleeding rates are consistent with PROTECT AF (lower in the device arm off anticoagulation), the extended follow-up results from PREVAIL may show an ongoing accrual of major bleeding events with medical anticoagulation that would improve the quality-adjusted survival and cost effectiveness of LAA closure over time.
Our cost-effectiveness estimates for PROTECT AF and PREVAIL were disparate because the studies were small, limiting the statistical precision of their findings and causing substantial variation in adverse event rates. As such, we think that our results for the 2 studies likely represent the range of possible cost-effectiveness estimates. However, given the larger patient experience of the PROTECT AF trial (707 patients compared with 407 in PREVAIL) and the much longer 3.8-year average follow-up time (compared with 18 months in PREVAIL), our estimates from PROTECT AF have less statistical uncertainty. In addition, a recently published study which included pooled data from the 4-year PROTECT AF follow-up, PREVAIL, and the 2 Continued Access Protocol registries showed that the major adverse event rates for the Continued Access Protocol registries (enrolling a combined 1145 patients) were consistent with those of the long-term PROTECT AF study, which corroborates those findings.73 Finally, as noted above, the adverse event rates for warfarin in PROTECT AF were much more consistent with those in the control arms of several recent studies evaluating the target-specific anticoagulants (Table I in the Data Supplement).4,68
Notably, periprocedural complications did not substantially influence the effectiveness or cost effectiveness of LAA closure in our study. Although periprocedural complications were more common in PROTECT AF than in PREVAIL, our analyses demonstrated that the model was relatively insensitive to changes in the risk of these events. These procedural complications occur acutely, and over time, their influence on quality-adjusted survival and cost effectiveness is overwhelmed by the effects of highly morbid and costly adverse events, such as stroke and ICH. Similarly, in a sensitivity analysis to simulate inexperienced operators in which we decreased the rate of successful LAA closure device implantation to 80% and increased each of the periprocedural adverse event rates to the highest value in their plausible ranges, we found that the quality-adjusted survival and cost effectiveness was only moderately affected.
For our study, several caveats should be considered. First, comparison of LAA closure to dabigatran is an indirect one because they have not been studied in any head-to-head trials. However, secondary analyses from RE-LY demonstrated that the effectiveness of dabigatran seemed consistent across many strata of patients, suggesting that it is reasonable to assume consistent effectiveness in a comparison with the population from the Watchman trials.4,5,74 Second, cost effectiveness may vary across the novel anticoagulants, but meta-analysis has demonstrated that major adverse event rates, including ischemic stroke, ICH, and death, are similar across the target-specific anticoagulants. Third, the base case inputs used from PROTECT AF and PREVAIL had different follow-up times, and extended follow-up could lead to significant differences in long-term event rates. In the index PROTECT AF publication with a mean follow-up of 18 months, LAA closure was noninferior to warfarin,16 whereas after a mean follow-up of almost 4 years, LAA closure was superior across several primary and secondary end points.18 Because PREVAIL has reported only 18-month follow-up to date,17 there may be greater uncertainty with PREVAIL-based estimates until longer-term data are reported. Fourth, clinical safety and effectiveness may depend on several factors not captured in these trials, including patient selection, operator or site factors, and concomitant use and duration of anticoagulation or antiplatelet therapy after LAA occlusion. If safety or effectiveness is different outside of the clinical trial setting, this could substantially affect value.75 Finally, our study findings only apply to patients who are eligible for anticoagulation because patients with contraindications to anticoagulation were excluded from both PROTECT AF and PREVAIL.
In conclusion, we found that the quality-adjusted survival and cost effectiveness of LAA closure with the Watchman device varies substantially depending on whether the clinical event rates reflect those of the PROTECT AF or PREVAIL clinical trials. The cost effectiveness of LAA closure using PROTECT AF data was in a range generally considered to be cost effective. Using data from PREVAIL, however, LAA closure was dominated by warfarin and dabigatran, meaning that it was less effective and more costly. PROTECT AF enrolled more patients and has substantially longer follow-up time, allowing greater statistical certainty with the cost-effectiveness results. Longer-term trial results and postmarketing surveillance of major adverse events will be vital to determining the ultimate value of this novel treatment modality in clinical practice.

Acknowledgments

We would like to acknowledge the assistance of Brian Salata in researching and assembling data inputs for this study.

Supplemental Material

File (circae_circae-2015-003407-t_supp1.pdf)

References

1.
Go AS, Hylek EM, Phillips KA, Chang Y, Henault LE, Selby JV, Singer DE. Prevalence of diagnosed atrial fibrillation in adults: national implications for rhythm management and stroke prevention: the AnTicoagulation and Risk Factors in Atrial Fibrillation (ATRIA) Study. JAMA. 2001;285:2370–2375.
2.
Naccarelli GV, Varker H, Lin J, Schulman KL. Increasing prevalence of atrial fibrillation and flutter in the United States. Am J Cardiol. 2009;104:1534–1539. doi: 10.1016/j.amjcard.2009.07.022.
3.
Warfarin versus aspirin for prevention of thromboembolism in atrial fibrillation: Stroke Prevention in Atrial Fibrillation II Study. Lancet. 1994;343:687–691.
4.
Connolly SJ, Ezekowitz MD, Yusuf S, Eikelboom J, Oldgren J, Parekh A, Pogue J, Reilly PA, Themeles E, Varrone J, Wang S, Alings M, Xavier D, Zhu J, Diaz R, Lewis BS, Darius H, Diener HC, Joyner CD, Wallentin L; RE-LY Steering Committee and Investigators. Dabigatran versus warfarin in patients with atrial fibrillation. N Engl J Med. 2009;361:1139–1151. doi: 10.1056/NEJMoa0905561.
5.
Connolly SJ, Ezekowitz MD, Yusuf S, Reilly PA, Wallentin L; Randomized Evaluation of Long-Term Anticoagulation Therapy Investigators. Newly identified events in the RE-LY trial. N Engl J Med. 2010;363:1875–1876. doi: 10.1056/NEJMc1007378.
6.
Patel MR, Mahaffey KW, Garg J, Pan G, Singer DE, Hacke W, Breithardt G, Halperin JL, Hankey GJ, Piccini JP, Becker RC, Nessel CC, Paolini JF, Berkowitz SD, Fox KA, Califf RM; ROCKET AF Investigators. Rivaroxaban versus warfarin in nonvalvular atrial fibrillation. N Engl J Med. 2011;365:883–891. doi: 10.1056/NEJMoa1009638.
7.
Granger CB, Alexander JH, McMurray JJ, Lopes RD, Hylek EM, Hanna M, Al-Khalidi HR, Ansell J, Atar D, Avezum A, Bahit MC, Diaz R, Easton JD, Ezekowitz JA, Flaker G, Garcia D, Geraldes M, Gersh BJ, Golitsyn S, Goto S, Hermosillo AG, Hohnloser SH, Horowitz J, Mohan P, Jansky P, Lewis BS, Lopez-Sendon JL, Pais P, Parkhomenko A, Verheugt FW, Zhu J, Wallentin L; ARISTOTLE Committees and Investigators. Apixaban versus warfarin in patients with atrial fibrillation. N Engl J Med. 2011;365:981–992. doi: 10.1056/NEJMoa1107039.
8.
Giugliano RP, Ruff CT, Braunwald E, Murphy SA, Wiviott SD, Halperin JL, Waldo AL, Ezekowitz MD, Weitz JI, Špinar J, Ruzyllo W, Ruda M, Koretsune Y, Betcher J, Shi M, Grip LT, Patel SP, Patel I, Hanyok JJ, Mercuri M, Antman EM; ENGAGE AF-TIMI 48 Investigators. Edoxaban versus warfarin in patients with atrial fibrillation. N Engl J Med. 2013;369:2093–2104. doi: 10.1056/NEJMoa1310907.
9.
Blackshear JL, Odell JA. Appendage obliteration to reduce stroke in cardiac surgical patients with atrial fibrillation. Ann Thorac Surg. 1996;61:755–759. doi: 10.1016/0003-4975(95)00887-X.
10.
Stoddard MF, Dawkins PR, Prince CR, Ammash NM. Left atrial appendage thrombus is not uncommon in patients with acute atrial fibrillation and a recent embolic event: a transesophageal echocardiographic study. J Am Coll Cardiol. 1995;25:452–459.
11.
Jain AK, Gallagher S. Percutaneous occlusion of the left atrial appendage in non-valvular atrial fibrillation for the prevention of thromboembolism: NICE guidance. Heart. 2011;97:762–765. doi: 10.1136/hrt.2010.208223.
12.
Bartus K, Bednarek J, Myc J, Kapelak B, Sadowski J, Lelakowski J, Yakubov SJ, Lee RJ. Feasibility of closed-chest ligation of the left atrial appendage in humans. Heart Rhythm. 2011;8:188–193. doi: 10.1016/j.hrthm.2010.10.040.
13.
Fountain R, Holmes DR, Hodgson PK, Chandrasekaran K, Van Tassel R, Sick P. Potential applicability and utilization of left atrial appendage occlusion devices in patients with atrial fibrillation. Am Heart J. 2006;152:720–723. doi: 10.1016/j.ahj.2006.05.001.
14.
Block PC, Burstein S, Casale PN, Kramer PH, Teirstein P, Williams DO, Reisman M. Percutaneous left atrial appendage occlusion for patients in atrial fibrillation suboptimal for warfarin therapy: 5-year results of the PLAATO (Percutaneous Left Atrial Appendage Transcatheter Occlusion) Study. JACC Cardiovasc Interv. 2009;2:594–600. doi: 10.1016/j.jcin.2009.05.005.
15.
Bartus K, Han FT, Bednarek J, Myc J, Kapelak B, Sadowski J, Lelakowski J, Bartus S, Yakubov SJ, Lee RJ. Percutaneous left atrial appendage suture ligation using the LARIAT device in patients with atrial fibrillation: initial clinical experience. J Am Coll Cardiol. 2013;62:108–118. doi: 10.1016/j.jacc.2012.06.046.
16.
Holmes DR, Reddy VY, Turi ZG, Doshi SK, Sievert H, Buchbinder M, Mullin CM, Sick P; PROTECT AF Investigators. Percutaneous closure of the left atrial appendage versus warfarin therapy for prevention of stroke in patients with atrial fibrillation: a randomised non-inferiority trial. Lancet. 2009;374:534–542. doi: 10.1016/S0140-6736(09)61343-X.
17.
Holmes DR, Kar S, Price MJ, Whisenant B, Sievert H, Doshi SK, Huber K, Reddy VY. Prospective randomized evaluation of the Watchman Left Atrial Appendage Closure device in patients with atrial fibrillation versus long-term warfarin therapy: the PREVAIL trial. J Am Coll Cardiol. 2014;64:1–12. doi: 10.1016/j.jacc.2014.04.029.
18.
Reddy VY, Sievert H, Halperin J, Doshi SK, Buchbinder M, Neuzil P, Huber K, Whisenant B, Kar S, Swarup V, Gordon N, Holmes D; PROTECT AF Steering Committee and Investigators. Percutaneous left atrial appendage closure vs warfarin for atrial fibrillation: a randomized clinical trial. JAMA. 2014;312:1988–1998. doi: 10.1001/jama.2014.15192.
19.
Singh SM, Micieli A, Wijeysundera HC. Economic evaluation of percutaneous left atrial appendage occlusion, dabigatran, and warfarin for stroke prevention in patients with nonvalvular atrial fibrillation. Circulation. 2013;127:2414–2423. doi: 10.1161/CIRCULATIONAHA.112.000920.
20.
Reddy VY, Akehurst RL, Armstrong SO, Amorosi SL, Beard SM, Holmes DR. Time to cost-effectiveness following stroke reduction strategies in AF: warfarin versus NOACs versus LAA closure. J Am Coll Cardiol. 2015;66:2728–2739. doi: 10.1016/j.jacc.2015.09.084.
21.
Sonnenberg FA, Beck JR. Markov models in medical decision making: a practical guide. Med Decis Making. 1993;13:322–338.
22.
Freeman JV, Zhu RP, Owens DK, Garber AM, Hutton DW, Go AS, Wang PJ, Turakhia MP. Cost-effectiveness of dabigatran compared with warfarin for stroke prevention in atrial fibrillation. Ann Intern Med. 2011;154:1–11. doi: 10.7326/0003-4819-154-1-201101040-00289.
23.
Weinstein MC, Siegel JE, Gold MR, Kamlet MS, Russell LB. Recommendations of the panel on cost-effectiveness in health and medicine. JAMA. 1996;276:1253–1258.
24.
FDA Executive Summary: Boston Scientific WATCHMAN® Left Atrial Appendage Closure Therapy. Federal Drug Administration; 2013. http://www.fda.gov/ucm/groups/fdagov-public/@fdagov-afda-adcom/documents/document/ucm377935.pdf. Accessed April 24, 2016.
25.
Antithrombotic Trialists’ Collaboration. Collaborative meta-analysis of randomised trials of antiplatelet therapy for prevention of death, myocardial infarction, and stroke in high risk patients. BMJ. 2002;324:71–86.
26.
Yuan Z, Bowlin S, Einstadter D, Cebul RD, Conners AR, Rimm AA. Atrial fibrillation as a risk factor for stroke: a retrospective cohort study of hospitalized Medicare beneficiaries. Am J Public Health. 1998;88:395–400.
27.
Wyse DG, Love JC, Yao Q, Carlson MD, Cassidy P, Greene LH, Martins JB, Ocampo C, Raitt MH, Schron E, Stamato NJ, Olarte A. Atrial fibrillation: a risk factor for increased mortality–an AVID registry analysis. J Interv Card Electrophysiol. 2001;5:267–273.
28.
Dennis MS, Burn JP, Sandercock PA, Bamford JM, Wade DT, Warlow CP. Long-term survival after first-ever stroke: the Oxfordshire Community Stroke Project. Stroke. 1993;24:796–800.
29.
O’Brien CL, Gage BF. Costs and effectiveness of ximelagatran for stroke prophylaxis in chronic atrial fibrillation. JAMA. 2005;293:699–706. doi: 10.1001/jama.293.6.699.
30.
Reddy VY, Möbius-Winkler S, Miller MA, Neuzil P, Schuler G, Wiebe J, Sick P, Sievert H. Left atrial appendage closure with the Watchman device in patients with a contraindication for oral anticoagulation: the ASAP study (ASA Plavix Feasibility Study With Watchman Left Atrial Appendage Closure Technology). J Am Coll Cardiol. 2013;61:2551–2556. doi: 10.1016/j.jacc.2013.03.035.
31.
van Walraven C, Hart RG, Singer DE, Laupacis A, Connolly S, Petersen P, Koudstaal PJ, Chang Y, Hellemons B. Oral anticoagulants vs aspirin in nonvalvular atrial fibrillation: an individual patient meta-analysis. JAMA. 2002;288:2441–2448.
32.
Mant J, Hobbs FD, Fletcher K, Roalfe A, Fitzmaurice D, Lip GY, Murray E; BAFTA investigators; Midland Research Practices Network (MidReC). Warfarin versus aspirin for stroke prevention in an elderly community population with atrial fibrillation (the Birmingham Atrial Fibrillation Treatment of the Aged Study, BAFTA): a randomised controlled trial. Lancet. 2007;370:493–503. doi: 10.1016/S0140-6736(07)61233-1.
33.
Hellemons BS, Langenberg M, Lodder J, Vermeer F, Schouten HJ, Lemmens T, van Ree JW, Knottnerus JA. Primary prevention of arterial thromboembolism in non-rheumatic atrial fibrillation in primary care: randomised controlled trial comparing two intensities of coumarin with aspirin. BMJ. 1999;319:958–964.
34.
Ezekowitz MD, Bridgers SL, James KE, Carliner NH, Colling CL, Gornick CC, Krause-Steinrauf H, Kurtzke JF, Nazarian SM, Radford MJ. Warfarin in the prevention of stroke associated with nonrheumatic atrial fibrillation. Veterans Affairs Stroke Prevention in Nonrheumatic Atrial Fibrillation Investigators. N Engl J Med. 1992;327:1406–1412. doi: 10.1056/NEJM199211123272002.
35.
Petersen P, Boysen G, Godtfredsen J, Andersen ED, Andersen B. Placebo-controlled, randomised trial of warfarin and aspirin for prevention of thromboembolic complications in chronic atrial fibrillation. The Copenhagen AFASAK study. Lancet. 1989;1:175–179.
36.
Gulløv AL, Koefoed BG, Petersen P, Pedersen TS, Andersen ED, Godtfredsen J, Boysen G. Fixed minidose warfarin and aspirin alone and in combination vs adjusted-dose warfarin for stroke prevention in atrial fibrillation: Second Copenhagen Atrial Fibrillation, Aspirin, and Anticoagulation Study. Arch Intern Med. 1998;158:1513–1521.
37.
Adjusted-dose warfarin versus low-intensity, fixed-dose warfarin plus aspirin for high-risk patients with atrial fibrillation: Stroke Prevention in Atrial Fibrillation III randomised clinical trial. Lancet. 1996;348:633–638.
38.
Secondary prevention in non-rheumatic atrial fibrillation after transient ischaemic attack or minor stroke. EAFT (European Atrial Fibrillation Trial) Study Group. Lancet. 1993;342:1255–1262.
39.
Connolly SJ, Laupacis A, Gent M, Roberts RS, Cairns JA, Joyner C. Canadian Atrial Fibrillation Anticoagulation (CAFA) Study. J Am Coll Cardiol. 1991;18:349–355.
40.
Hylek EM, Go AS, Chang Y, Jensvold NG, Henault LE, Selby JV, Singer DE. Effect of intensity of oral anticoagulation on stroke severity and mortality in atrial fibrillation. N Engl J Med. 2003;349:1019–1026. doi: 10.1056/NEJMoa022913.
41.
Stroke Prevention in Atrial Fibrillation Study. Final results. Circulation. 1991;84:527–539.
42.
Albers GW, Diener HC, Frison L, Grind M, Nevinson M, Partridge S, Halperin JL, Horrow J, Olsson SB, Petersen P, Vahanian A; SPORTIF Executive Steering Committee for the SPORTIF V Investigators. Ximelagatran vs warfarin for stroke prevention in patients with nonvalvular atrial fibrillation: a randomized trial. JAMA. 2005;293:690–698. doi: 10.1001/jama.293.6.690.
43.
Olsson SB; Executive Steering Committee of the SPORTIF III Investigators. Stroke prevention with the oral direct thrombin inhibitor ximelagatran compared with warfarin in patients with non-valvular atrial fibrillation (SPORTIF III): randomised controlled trial. Lancet. 2003;362:1691–1698.
44.
Fang MC, Go AS, Chang Y, Hylek EM, Henault LE, Jensvold NG, Singer DE. Death and disability from warfarin-associated intracranial and extracranial hemorrhages. Am J Med. 2007;120:700–705. doi: 10.1016/j.amjmed.2006.07.034.
45.
Gage BF, Yan Y, Milligan PE, Waterman AD, Culverhouse R, Rich MW, Radford MJ. Clinical classification schemes for predicting hemorrhage: results from the National Registry of Atrial Fibrillation (NRAF). Am Heart J. 2006;151:713–719. doi: 10.1016/j.ahj.2005.04.017.
46.
Evans A, Kalra L. Are the results of randomized controlled trials on anticoagulation in patients with atrial fibrillation generalizable to clinical practice? Arch Intern Med. 2001;161:1443–1447.
47.
Copland M, Walker ID, Tait RC. Oral anticoagulation and hemorrhagic complications in an elderly population with atrial fibrillation. Arch Intern Med. 2001;161:2125–2128.
48.
Gage BF, Cardinalli AB, Owens DK. The effect of stroke and stroke prophylaxis with aspirin or warfarin on quality of life. Arch Intern Med. 1996;156:1829–1836.
49.
Sullivan PW, Ghushchyan V. Preference-based EQ-5D index scores for chronic conditions in the United States. Med Decis Making. 2006;26:410–420. doi: 10.1177/0272989X06290495.
50.
Thomson R, Parkin D, Eccles M, Sudlow M, Robinson A. Decision analysis and guidelines for anticoagulant therapy to prevent stroke in patients with atrial fibrillation. Lancet. 2000;355:956–962. doi: 10.1016/S0140-6736(00)90012-6.
51.
Fryback DG, Dasbach EJ, Klein R, Klein BE, Dorn N, Peterson K, Martin PA. The Beaver Dam Health Outcomes Study: initial catalog of health-state quality factors. Med Decis Making. 1993;13:89–102.
52.
Owens DK, Sanders GD, Harris RA, McDonald KM, Heidenreich PA, Dembitzer AD, Hlatky MA. Cost-effectiveness of implantable cardioverter defibrillators relative to amiodarone for prevention of sudden cardiac death. Ann Intern Med. 1997;126:1–12.
53.
Red Book. Montvale, NJ: Thomson Reuters; 2009.
54.
Coaguchek. 2015; http://coagucheck.com. Accessed October 1, 2015.
55.
HCUPnet, Healthcare Cost and Utilization Project. 2015; http://hcupnet.ahrq.gov. Accessed October 1, 2015.
56.
Leibson CL, Hu T, Brown RD, Hass SL, O’Fallon WM, Whisnant JP. Utilization of acute care services in the year before and after first stroke: a population-based study. Neurology. 1996;46:861–869.
57.
Holloway RG, Witter DM, Lawton KB, Lipscomb J, Samsa G. Inpatient costs of specific cerebrovascular events at five academic medical centers. Neurology. 1996;46:854–860.
58.
Matchar DB, Samsa GP. Secondary and Tertiary Prevention of Stroke: Patient Outcomes Research Team (PORT) Final Report- Phase 1. 2000; .
59.
Russell MW, Boulanger L, Joshi AV, Neumann PJ, Menzin J. The economic burden of intracerebral hemorrhage: evidence from managed care. Manag Care Interface. 2006;19:24–28, 34.
60.
Lee WC, Christensen MC, Joshi AV, Pashos CL. Long-term cost of stroke subtypes among Medicare beneficiaries. Cerebrovasc Dis. 2007;23:57–65. doi: 10.1159/000096542.
61.
Eriksson BI, Dahl OE, Rosencher N, Kurth AA, van Dijk CN, Frostick SP, Prins MH, Hettiarachchi R, Hantel S, Schnee J, Büller HR; RE-NOVATE Study Group. Dabigatran etexilate versus enoxaparin for prevention of venous thromboembolism after total hip replacement: a randomised, double-blind, non-inferiority trial. Lancet. 2007;370:949–956. doi: 10.1016/S0140-6736(07)61445-7.
62.
Mark DB, Knight JD, Cowper PA, Davidson-Ray L, Anstrom KJ. Long-term economic outcomes associated with intensive versus moderate lipid-lowering therapy in coronary artery disease: results from the Treating to New Targets (TNT) Trial. Am Heart J. 2008;156:698–705. doi: 10.1016/j.ahj.2008.05.032.
63.
Hirsch AT, Hartman L, Town RJ, Virnig BA. National health care costs of peripheral arterial disease in the Medicare population. Vasc Med. 2008;13:209–215. doi: 10.1177/1358863X08089277.
64.
Jaff MR, Cahill KE, Yu AP, Birnbaum HG, Engelhart LM. Clinical outcomes and medical care costs among medicare beneficiaries receiving therapy for peripheral arterial disease. Ann Vasc Surg. 2010;24:577–587. doi: 10.1016/j.avsg.2010.03.015.
65.
Agency for Healthcare Research and Quality. Medical Expenditure Panel Survey (MEPS). 2015; http://meps.ahrq.gov. Accessed October 1, 2015.
66.
PharmacyChecker.com. 2015; http://pharmacychecker.com. Accessed October 1, 2015.
67.
Gage BF, Fihn SD, White RH. Management and dosing of warfarin therapy. Am J Med. 2000;109:481–488.
68.
CPT Code/Relative Value Search. AMABookstore.com. 2015; http://AMABookstore.com. Accessed October 1, 2015.
69.
Catheter Ablation Versus Anti-arrhythmic Drug Therapy for Atrial Fibrillation Trial (CABANA). ClinicalTrialsgov. 2009.
70.
Kauf TL, Velazquez EJ, Crosslin DR, Weaver WD, Diaz R, Granger CB, McMurray JJ, Rouleau JL, Aylward PE, White HD, Califf RM, Schulman KA. The cost of acute myocardial infarction in the new millennium: evidence from a multinational registry. Am Heart J. 2006;151:206–212. doi: 10.1016/j.ahj.2005.02.028.
71.
Tsevat J, Kuntz KM, Orav EJ, Weinstein MC, Sacks FM, Goldman L. Cost-effectiveness of pravastatin therapy for survivors of myocardial infarction with average cholesterol levels. Am Heart J. 2001;141:727–734. doi: 10.1067/mhj.2001.114805.
72.
Doubilet P, Begg CB, Weinstein MC, Braun P, McNeil BJ. Probabilistic sensitivity analysis using Monte Carlo simulation. A practical approach. Med Decis Making. 1985;5:157–177.
73.
Holmes DR, Doshi SK, Kar S, Price MJ, Sanchez JM, Sievert H, Valderrabano M, Reddy VY. Left atrial appendage closure as an alternative to warfarin for stroke prevention in atrial fibrillation: a patient-level meta-analysis. J Am Coll Cardiol. 2015;65:2614–2623. doi: 10.1016/j.jacc.2015.04.025.
74.
Diener HC, Connolly SJ, Ezekowitz MD, Wallentin L, Reilly PA, Yang S, Xavier D, Di Pasquale G, Yusuf S; RE-LY study group. Dabigatran compared with warfarin in patients with atrial fibrillation and previous transient ischaemic attack or stroke: a subgroup analysis of the RE-LY trial. Lancet Neurol. 2010;9:1157–1163. doi: 10.1016/S1474-4422(10)70274-X.
75.
Waterman AD, Milligan PE, Bayer L, Banet GA, Gatchel SK, Gage BF. Effect of warfarin nonadherence on control of the international normalized ratio. Am J Health Syst Pharm. 2004;61:1258–1264.

eLetters(0)

eLetters should relate to an article recently published in the journal and are not a forum for providing unpublished data. Comments are reviewed for appropriate use of tone and language. Comments are not peer-reviewed. Acceptable comments are posted to the journal website only. Comments are not published in an issue and are not indexed in PubMed. Comments should be no longer than 500 words and will only be posted online. References are limited to 10. Authors of the article cited in the comment will be invited to reply, as appropriate.

Comments and feedback on AHA/ASA Scientific Statements and Guidelines should be directed to the AHA/ASA Manuscript Oversight Committee via its Correspondence page.

Information & Authors

Information

Published In

Go to Circulation: Arrhythmia and Electrophysiology
Go to Circulation: Arrhythmia and Electrophysiology
Circulation: Arrhythmia and Electrophysiology
PubMed: 27307517

History

Received: 8 February 2015
Accepted: 31 March 2016
Published in print: June 2016
Published online: 15 June 2016

Permissions

Request permissions for this article.

Keywords

  1. anticoagulants
  2. atrial appendage
  3. atrial fibrillation
  4. intracranial hemorrhage
  5. pericardial effusion

Subjects

Authors

Affiliations

James V. Freeman, MD, MPH, MS
From the Yale University School of Medicine, New Haven, CT (J.V.F.); University of Michigan, Ann Arbor (D.W.H., G.D.B., R.P.Z.); VA Palo Alto Health Care System, CA (D.K.O., P.A.H., M.P.T.); Stanford University School of Medicine, CA (D.K.O., A.S.G., M.A.H., P.A.H., P.J.W., M.P.T.); Harvard University, Cambridge, MA (A.M.G.); Kaiser Permanente Northern California Division of Research, Oakland (A.S.G.); University of California, San Francisco (A.S.G.); and Texas Cardiac Arrhythmia Institute, Austin (A.A.-A.).
David W. Hutton, PhD
From the Yale University School of Medicine, New Haven, CT (J.V.F.); University of Michigan, Ann Arbor (D.W.H., G.D.B., R.P.Z.); VA Palo Alto Health Care System, CA (D.K.O., P.A.H., M.P.T.); Stanford University School of Medicine, CA (D.K.O., A.S.G., M.A.H., P.A.H., P.J.W., M.P.T.); Harvard University, Cambridge, MA (A.M.G.); Kaiser Permanente Northern California Division of Research, Oakland (A.S.G.); University of California, San Francisco (A.S.G.); and Texas Cardiac Arrhythmia Institute, Austin (A.A.-A.).
Geoffrey D. Barnes, MD, MSc
From the Yale University School of Medicine, New Haven, CT (J.V.F.); University of Michigan, Ann Arbor (D.W.H., G.D.B., R.P.Z.); VA Palo Alto Health Care System, CA (D.K.O., P.A.H., M.P.T.); Stanford University School of Medicine, CA (D.K.O., A.S.G., M.A.H., P.A.H., P.J.W., M.P.T.); Harvard University, Cambridge, MA (A.M.G.); Kaiser Permanente Northern California Division of Research, Oakland (A.S.G.); University of California, San Francisco (A.S.G.); and Texas Cardiac Arrhythmia Institute, Austin (A.A.-A.).
Ruo P. Zhu, MD
From the Yale University School of Medicine, New Haven, CT (J.V.F.); University of Michigan, Ann Arbor (D.W.H., G.D.B., R.P.Z.); VA Palo Alto Health Care System, CA (D.K.O., P.A.H., M.P.T.); Stanford University School of Medicine, CA (D.K.O., A.S.G., M.A.H., P.A.H., P.J.W., M.P.T.); Harvard University, Cambridge, MA (A.M.G.); Kaiser Permanente Northern California Division of Research, Oakland (A.S.G.); University of California, San Francisco (A.S.G.); and Texas Cardiac Arrhythmia Institute, Austin (A.A.-A.).
Douglas K. Owens, MD, MSc
From the Yale University School of Medicine, New Haven, CT (J.V.F.); University of Michigan, Ann Arbor (D.W.H., G.D.B., R.P.Z.); VA Palo Alto Health Care System, CA (D.K.O., P.A.H., M.P.T.); Stanford University School of Medicine, CA (D.K.O., A.S.G., M.A.H., P.A.H., P.J.W., M.P.T.); Harvard University, Cambridge, MA (A.M.G.); Kaiser Permanente Northern California Division of Research, Oakland (A.S.G.); University of California, San Francisco (A.S.G.); and Texas Cardiac Arrhythmia Institute, Austin (A.A.-A.).
Alan M. Garber, MD, PhD
From the Yale University School of Medicine, New Haven, CT (J.V.F.); University of Michigan, Ann Arbor (D.W.H., G.D.B., R.P.Z.); VA Palo Alto Health Care System, CA (D.K.O., P.A.H., M.P.T.); Stanford University School of Medicine, CA (D.K.O., A.S.G., M.A.H., P.A.H., P.J.W., M.P.T.); Harvard University, Cambridge, MA (A.M.G.); Kaiser Permanente Northern California Division of Research, Oakland (A.S.G.); University of California, San Francisco (A.S.G.); and Texas Cardiac Arrhythmia Institute, Austin (A.A.-A.).
Alan S. Go, MD
From the Yale University School of Medicine, New Haven, CT (J.V.F.); University of Michigan, Ann Arbor (D.W.H., G.D.B., R.P.Z.); VA Palo Alto Health Care System, CA (D.K.O., P.A.H., M.P.T.); Stanford University School of Medicine, CA (D.K.O., A.S.G., M.A.H., P.A.H., P.J.W., M.P.T.); Harvard University, Cambridge, MA (A.M.G.); Kaiser Permanente Northern California Division of Research, Oakland (A.S.G.); University of California, San Francisco (A.S.G.); and Texas Cardiac Arrhythmia Institute, Austin (A.A.-A.).
Mark A. Hlatky, MD
From the Yale University School of Medicine, New Haven, CT (J.V.F.); University of Michigan, Ann Arbor (D.W.H., G.D.B., R.P.Z.); VA Palo Alto Health Care System, CA (D.K.O., P.A.H., M.P.T.); Stanford University School of Medicine, CA (D.K.O., A.S.G., M.A.H., P.A.H., P.J.W., M.P.T.); Harvard University, Cambridge, MA (A.M.G.); Kaiser Permanente Northern California Division of Research, Oakland (A.S.G.); University of California, San Francisco (A.S.G.); and Texas Cardiac Arrhythmia Institute, Austin (A.A.-A.).
Paul A. Heidenreich, MD, MS
From the Yale University School of Medicine, New Haven, CT (J.V.F.); University of Michigan, Ann Arbor (D.W.H., G.D.B., R.P.Z.); VA Palo Alto Health Care System, CA (D.K.O., P.A.H., M.P.T.); Stanford University School of Medicine, CA (D.K.O., A.S.G., M.A.H., P.A.H., P.J.W., M.P.T.); Harvard University, Cambridge, MA (A.M.G.); Kaiser Permanente Northern California Division of Research, Oakland (A.S.G.); University of California, San Francisco (A.S.G.); and Texas Cardiac Arrhythmia Institute, Austin (A.A.-A.).
Paul J. Wang, MD
From the Yale University School of Medicine, New Haven, CT (J.V.F.); University of Michigan, Ann Arbor (D.W.H., G.D.B., R.P.Z.); VA Palo Alto Health Care System, CA (D.K.O., P.A.H., M.P.T.); Stanford University School of Medicine, CA (D.K.O., A.S.G., M.A.H., P.A.H., P.J.W., M.P.T.); Harvard University, Cambridge, MA (A.M.G.); Kaiser Permanente Northern California Division of Research, Oakland (A.S.G.); University of California, San Francisco (A.S.G.); and Texas Cardiac Arrhythmia Institute, Austin (A.A.-A.).
Amin Al-Ahmad, MD
From the Yale University School of Medicine, New Haven, CT (J.V.F.); University of Michigan, Ann Arbor (D.W.H., G.D.B., R.P.Z.); VA Palo Alto Health Care System, CA (D.K.O., P.A.H., M.P.T.); Stanford University School of Medicine, CA (D.K.O., A.S.G., M.A.H., P.A.H., P.J.W., M.P.T.); Harvard University, Cambridge, MA (A.M.G.); Kaiser Permanente Northern California Division of Research, Oakland (A.S.G.); University of California, San Francisco (A.S.G.); and Texas Cardiac Arrhythmia Institute, Austin (A.A.-A.).
Mintu P. Turakhia, MD, MAS
From the Yale University School of Medicine, New Haven, CT (J.V.F.); University of Michigan, Ann Arbor (D.W.H., G.D.B., R.P.Z.); VA Palo Alto Health Care System, CA (D.K.O., P.A.H., M.P.T.); Stanford University School of Medicine, CA (D.K.O., A.S.G., M.A.H., P.A.H., P.J.W., M.P.T.); Harvard University, Cambridge, MA (A.M.G.); Kaiser Permanente Northern California Division of Research, Oakland (A.S.G.); University of California, San Francisco (A.S.G.); and Texas Cardiac Arrhythmia Institute, Austin (A.A.-A.).

Notes

Correspondence to James V. Freeman, MD, MPH, MS, Yale University School of Medicine, PO Box 208017, New Haven, CT 06520. E-mail [email protected]

Disclosures

Dr Freeman has received a research grant from the National Heart, Lung, and Blood Institute (grant K23 HL118147-01) and consulting fees from Janssen Scientific (modest). Dr Barnes has received research grants from Blue Cross-Blue Shield of Michigan/Blue Care Network and Bristol-Myers Squibb/Pfizer and had received consulting fees from Portola (modest). Dr Owens has received research grants from the Department of Veterans Affairs. Dr Go has received research grants from the National Heart, Lung, and Blood Institute (grants U19 HL091179 and RC2 HL101589) and iRhythm. Dr Hlatky has received research grants from Acumen, Inc and sits on the Medical Advisory Panel, Technology Evaluation Center, Blue Cross-Blue Shield Association. Dr Wang has received fellowship program support from Boston Scientific and St Jude Medical. Dr Turakhia has received research grants from the Veterans Affairs Health Services Research & Development Office (grant CDA09027-1). The other authors report no conflicts.

Sources of Funding

Dr Freeman was supported by a grant from the National Heart, Lung, and Blood Institute (K23 HL118147-01). Dr Barnes was supported by a grant from the National Heart, Lung, and Blood Institute (2-T32-HL007853-16). Dr Owens was supported by the Department of Veterans Affairs. Dr Turakhia was supported by a grant from the Veterans Affairs Health Services Research & Development Office (CDA09027-1). The funding sources had no role in the design and conduct of the study; in the collection, analysis, and interpretation of the data; in the reporting, preparation, or review of the article; or in the decision to submit the article for publication.

Metrics & Citations

Metrics

Citations

Download Citations

If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Select your manager software from the list below and click Download.

  1. Embolization of percutaneous left atrial appendage closure devices: Timing, management and clinical outcomes, Cardiovascular Revascularization Medicine, 64, (7-14), (2024).https://doi.org/10.1016/j.carrev.2024.02.014
    Crossref
  2. Cost-effectiveness of left atrial appendage closure for stroke prevention in atrial fibrillation: a systematic review appraising the methodological quality, Cost Effectiveness and Resource Allocation, 21, 1, (2023).https://doi.org/10.1186/s12962-023-00486-0
    Crossref
  3. Cost-effectiveness of left atrial appendage closure with Watchman for non-valvular atrial fibrillation patients in Japan, Journal of Medical Economics, 26, 1, (1357-1367), (2023).https://doi.org/10.1080/13696998.2023.2266275
    Crossref
  4. Cost Effectiveness of Strategies to Manage Atrial Fibrillation in Middle- and High-Income Countries: A Systematic Review, PharmacoEconomics, 41, 8, (913-943), (2023).https://doi.org/10.1007/s40273-023-01276-5
    Crossref
  5. Actual management costs of patients with non-valvular atrial fibrillation treated with percutaneous left atrial appendage closure or oral anticoagulation, International Journal of Cardiology, 351, (61-64), (2022).https://doi.org/10.1016/j.ijcard.2021.12.027
    Crossref
  6. In Search of the Optimal Antithrombotic Regimen for Intracerebral Hemorrhage Survivors with Atrial Fibrillation, Drugs, 82, 9, (965-977), (2022).https://doi.org/10.1007/s40265-022-01729-9
    Crossref
  7. Percutaneous left atrial appendage closure reduces cost of care independent of the institutional cumulative caseload in patients with non-valvular atrial fibrillation, Netherlands Heart Journal, 30, 10, (481-485), (2022).https://doi.org/10.1007/s12471-022-01675-x
    Crossref
  8. Cost‐Effectiveness of Coronary Artery Bypass Grafting and Percutaneous Coronary Intervention in Patients With Chronic Kidney Disease and Acute Coronary Syndromes in the US Medicare Program, Journal of the American Heart Association, 10, 7, (2021)./doi/10.1161/JAHA.120.019391
    Abstract
  9. Clinical outcomes of patients undergoing percutaneous left atrial appendage occlusion in general anaesthesia or conscious sedation: data from the prospective global Amplatzer Amulet Occluder Observational Study, BMJ Open, 11, 3, (e040455), (2021).https://doi.org/10.1136/bmjopen-2020-040455
    Crossref
  10. Cost-effectiveness of combined catheter ablation and left atrial appendage closure for symptomatic atrial fibrillation in patients with high stroke and bleeding risk, American Heart Journal, 231, (110-120), (2021).https://doi.org/10.1016/j.ahj.2020.08.008
    Crossref
  11. See more
Loading...

View Options

View options

PDF and All Supplements

Download PDF and All Supplements

PDF/EPUB

View PDF/EPUB
Login options

Check if you have access through your login credentials or your institution to get full access on this article.

Personal login Institutional Login
Purchase Options

Purchase this article to access the full text.

Purchase access to this article for 24 hours

Cost-Effectiveness of Percutaneous Closure of the Left Atrial Appendage in Atrial Fibrillation Based on Results From PROTECT AF Versus PREVAIL
Circulation: Arrhythmia and Electrophysiology
  • Vol. 9
  • No. 6

Purchase access to this journal for 24 hours

Circulation: Arrhythmia and Electrophysiology
  • Vol. 9
  • No. 6
Restore your content access

Enter your email address to restore your content access:

Note: This functionality works only for purchases done as a guest. If you already have an account, log in to access the content to which you are entitled.

Figures

Tables

Media

Share

Share

Share article link

Share

Comment Response