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Comparative effects of antiplatelet, anticoagulant, or combined therapy in patients with valvular and nonvalvular atrial fibrillation
Arrhythmias
Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM)? Methods: In AFFIRM, 4060 patients (mean age 70 years) were randomly assigned either to rhythm or rate control. Survival data were analyzed, along with the resources used after randomization. Resources consisted of hospitalization days, cardiac procedures, cardioversion, emergency room visits, and medications. Costs were estimated by multiplying the number of each resource used by its unit cost from the perspective of a third-party payer and expressed in 2002 dollars. Results: The mean survival time was 4.6 years in the rhythm-control arm and 4.7 years in the rate-control arm. During a mean follow-up of 3.5 years, costs in the rhythmcontrol and rate-control arms were $25,623 and $20,546, respectively. The incremental cost of rhythm control of $5077 was attributable to more hospitalizations, cardioversions, and emergency room visits. Conclusions: Compared to a rate-control strategy, a rhythmcontrol strategy does not improve survival and is more costly. Therefore, rate control is the more cost-effective strategy for management of AF. Perspective: It should be kept in mind that these results apply only to patients similar to the AFFIRM population (i.e., elderly patients, generally with mild or no symptoms). Furthermore, this study did not include quality of life (QOL) in the cost-effectiveness analysis. In younger patients whose QOL is severely impaired by AF, the benefits of rhythm control are obvious, and adjustment of cost-effectiveness for QOL might well demonstrate an advantage of rhythm control over rate control. FM
Abstracts Comparative Effects of Antiplatelet, Anticoagulant, or Combined Therapy in Patients With Valvular and Nonvalvular Atrial Fibrillation Perez-Gomez F, Alegria E, Berjon J, et al. J Am Coll Cardiol 2004;44:1557– 66. Study Question: How effective are an antiplatelet agent (triflusal) and an anticoagulant (acenocumerol), alone or in combination, for preventing thromboembolic events in patients with atrial fibrillation (AF)? Methods: This was an unblinded, randomized comparison of triflusal and acenocumerol in 1209 patients with AF and risk factors for stroke. High-risk patients (n⫽495) with mitral stenosis or prior stroke were randomized either to acenocumerol with a target international normalized ratio (INR) of 2–3, or to a combination of triflusal, 600 mg daily plus acenocumerol with a target INR of 1.4 –2.4. A third arm in intermediate-risk patients (n⫽714) was triflusal, 600 mg daily. The mean duration of follow-up was 2.7 years. Primary end points were vascular death, transient ischemic attack or nonfatal stroke/embolism. Results: Primary end point events were less common with combined therapy than with acenocumerol in the intermediate-risk group (hazard ratio [HR] 0.33) and in the highrisk group (HR 0.5). Compared with individual therapy, combined therapy was associated with a 61% lower risk of primary end point events plus severe bleeding. There was no difference in bleeding events between combined therapy and acenocumerol. Conclusions: Combined therapy with acenocumerol plus triflusal is associated with fewer thromboembolic events than acenocumerol by itself in patients with AF, and does not increase the risk of hemorrhagic complications. Perspective: This is the first study to show that an antiplatelet agent lowers the risk of thromboembolism from AF when added to an anticoagulant. Neither acenocumerol nor triflusal is available in the U.S. Acenocumerol is very similar to warfarin, but triflusal causes less bleeding than aspirin. Therefore, it is unclear whether the results apply to a warfarin/aspirin combination. FM
Misdiagnosis of Atrial Fibrillation and Its Clinical Consequences Bogun F, Anh D, Kalahasty G, et al. Am J Med 2004;117:636 – 42. Study Question: How often do computer algorithms incorrectly diagnose atrial fibrillation (AF), and what is the clinical impact of the computer errors? Methods: Two electrophysiologists reviewed 2298 electrocardiograms (ECGs) (from 1085 patients) with a preliminary computer-generated diagnosis of AF. The ECGs were over-read by a cardiologist, with a 2–5-day lag between the day the ECG was performed and the time the final interpretation was available in the hospital computer system. When the computer-generated diagnosis of AF was incorrect, a chart review was performed to determine whether the incorrect diagnosis had resulted in any unnecessary testing or therapy. Results: The computer-generated diagnosis of AF was incorrect in 382 patients (mean age 74 years) and in 19% of all ECGs. The actual diagnosis most commonly was sinus rhythm with premature beats or artifact. In 39 of the 382
Cost-Effectiveness of Rhythm Versus Rate Control in Atrial Fibrillation Marshall DA, Levy AR, Vidaillet H, et al. Ann Intern Med 2004; 141:653– 61. Study Question: How does the cost of a rhythm-control strategy compare with that of a rate-control strategy in patients with atrial fibrillation (AF) enrolled in the Atrial
ACC CURRENT JOURNAL REVIEW February 2005
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Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM)? Methods: In AFFIRM, 4060 patients (mean age 70 years) were randomly assigned either to rhythm or rate control. Survival data were analyzed, along with the resources used after randomization. Resources consisted of hospitalization days, cardiac procedures, cardioversion, emergency room visits, and medications. Costs were estimated by multiplying the number of each resource used by its unit cost from the perspective of a third-party payer and expressed in 2002 dollars. Results: The mean survival time was 4.6 years in the rhythm-control arm and 4.7 years in the rate-control arm. During a mean follow-up of 3.5 years, costs in the rhythmcontrol and rate-control arms were $25,623 and $20,546, respectively. The incremental cost of rhythm control of $5077 was attributable to more hospitalizations, cardioversions, and emergency room visits. Conclusions: Compared to a rate-control strategy, a rhythmcontrol strategy does not improve survival and is more costly. Therefore, rate control is the more cost-effective strategy for management of AF. Perspective: It should be kept in mind that these results apply only to patients similar to the AFFIRM population (i.e., elderly patients, generally with mild or no symptoms). Furthermore, this study did not include quality of life (QOL) in the cost-effectiveness analysis. In younger patients whose QOL is severely impaired by AF, the benefits of rhythm control are obvious, and adjustment of cost-effectiveness for QOL might well demonstrate an advantage of rhythm control over rate control. FM
Abstracts Comparative Effects of Antiplatelet, Anticoagulant, or Combined Therapy in Patients With Valvular and Nonvalvular Atrial Fibrillation Perez-Gomez F, Alegria E, Berjon J, et al. J Am Coll Cardiol 2004;44:1557– 66. Study Question: How effective are an antiplatelet agent (triflusal) and an anticoagulant (acenocumerol), alone or in combination, for preventing thromboembolic events in patients with atrial fibrillation (AF)? Methods: This was an unblinded, randomized comparison of triflusal and acenocumerol in 1209 patients with AF and risk factors for stroke. High-risk patients (n⫽495) with mitral stenosis or prior stroke were randomized either to acenocumerol with a target international normalized ratio (INR) of 2–3, or to a combination of triflusal, 600 mg daily plus acenocumerol with a target INR of 1.4 –2.4. A third arm in intermediate-risk patients (n⫽714) was triflusal, 600 mg daily. The mean duration of follow-up was 2.7 years. Primary end points were vascular death, transient ischemic attack or nonfatal stroke/embolism. Results: Primary end point events were less common with combined therapy than with acenocumerol in the intermediate-risk group (hazard ratio [HR] 0.33) and in the highrisk group (HR 0.5). Compared with individual therapy, combined therapy was associated with a 61% lower risk of primary end point events plus severe bleeding. There was no difference in bleeding events between combined therapy and acenocumerol. Conclusions: Combined therapy with acenocumerol plus triflusal is associated with fewer thromboembolic events than acenocumerol by itself in patients with AF, and does not increase the risk of hemorrhagic complications. Perspective: This is the first study to show that an antiplatelet agent lowers the risk of thromboembolism from AF when added to an anticoagulant. Neither acenocumerol nor triflusal is available in the U.S. Acenocumerol is very similar to warfarin, but triflusal causes less bleeding than aspirin. Therefore, it is unclear whether the results apply to a warfarin/aspirin combination. FM
Misdiagnosis of Atrial Fibrillation and Its Clinical Consequences Bogun F, Anh D, Kalahasty G, et al. Am J Med 2004;117:636 – 42. Study Question: How often do computer algorithms incorrectly diagnose atrial fibrillation (AF), and what is the clinical impact of the computer errors? Methods: Two electrophysiologists reviewed 2298 electrocardiograms (ECGs) (from 1085 patients) with a preliminary computer-generated diagnosis of AF. The ECGs were over-read by a cardiologist, with a 2–5-day lag between the day the ECG was performed and the time the final interpretation was available in the hospital computer system. When the computer-generated diagnosis of AF was incorrect, a chart review was performed to determine whether the incorrect diagnosis had resulted in any unnecessary testing or therapy. Results: The computer-generated diagnosis of AF was incorrect in 382 patients (mean age 74 years) and in 19% of all ECGs. The actual diagnosis most commonly was sinus rhythm with premature beats or artifact. In 39 of the 382
Cost-Effectiveness of Rhythm Versus Rate Control in Atrial Fibrillation Marshall DA, Levy AR, Vidaillet H, et al. Ann Intern Med 2004; 141:653– 61. Study Question: How does the cost of a rhythm-control strategy compare with that of a rate-control strategy in patients with atrial fibrillation (AF) enrolled in the Atrial
ACC CURRENT JOURNAL REVIEW February 2005
59