CardiosourceNews from Heart Rhythm 2010
Official Title: J-Rhythm II Study. A randomized study of Angiotensin II Type 1 Receptor Blocker vs. Dihydropyridine Ca Antagonist for Treatment of Paroxysmal Atrial Fibrillation in Patients with Hypertension
Event: Heart Rhythm 2010
Topic(s): Prevention/Vascular
Presenter: Takeshi Yamashita
Writer(s): Fred M. Kusumoto, M.D., F.A.C.C.
Date Posted: 5/14/2010
Summary
In patients with hypertension and paroxysmal atrial fibrillation, both candesartan and amlodipine reduce blood pressure and frequency of atrial fibrillation at one-year follow-up with no significant differences between the agents for decreasing arrhythmia burden.
Background
Atrial fibrillation is present in 5-7 million people in the United States and is associated with significant morbidity and increased mortality, particularly in those patients with cardiovascular risk factors (Miyasaka et al, Fuster et al). Although radiofrequency catheter ablation and antiarrhythmic medication can be effective for reducing symptoms in selected populations, defining optimal “upstream” strategies for reducing the development or progression of atrial fibrillation would have a far larger impact on overall healthcare.
Study Design
The J-RHYTHM II trial randomized 318 patients with hypertension and paroxysmal atrial fibrillation in an open label manner to candesartan (8-12 mg) or amlodipine (2.5-5 mg). Daily transtelephonic monitoring was performed for one month prior to randomization and during one-year follow-up. The primary endpoint was difference in the number of days per month with atrial fibrillation between baseline and the last month of follow-up. Secondary endpoints included development of persistent atrial fibrillation and/or requiring cardioversion, changes in left atrial dimension, and changes in quality-of-life indices.
Results and Conclusions
Both candesartan and amlodipine reduced the number of days that patients were in atrial fibrillation after one year of therapy as compared with the pre-treatment month-long monitoring period: (candesartan: Decrease in 1.5 days/month; amlodipine: Decrease in 2.5 days/month). There was with no significant difference detected between the two therapies. Both candesartan and amlodipine reduced blood pressure after one year relative to baseline, although amlodipine was more effective than candesartan. During the study period 8% of patients treated with candesartan and 15% of patients treated with amlodipine developed persistent atrial fibrillation or required cardioverion (p = 0.08). Both amlodipine and candesartan were associated with improvement in quality-of-life indices after one year of treatment.
Perspective
The results of the J_RHYTHM II trial emphasize the importance of blood pressure control in patients with hypertension and atrial fibrillation. Different hypertension treatment strategies were not associated with differences in arrhythmia burden. However, in this study population, 70% of patients were being treated with Class I antiarrhythmic medication. It is possible that there may be differences between hypertension treatments for the progression or development of atrial fibrillation in other populations where the arrhythmia hasd not yet developed or is less established.
References
Miyasaka Y, Barnes ME, Gersh BJ, et al. Secular trends in incidence of atrial fibrillation in Olmsted County, Minnesota, 1980 to 2000, and implications on the projections for future prevalence. Circulation 2006;114:119-25
ACC/AHA Task Force on Practice Guidelines; European Society of Cardiology Committee for Practice Guidelines; Writing Committee to Revise the 2001 Guidelines for the Management of Patients With Atrial Fibrillation ACC/AHA/ESC 2006 guidelines for the management of patients with atrial fibrillation--executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guidelines for the Management of Patients With Atrial Fibrillation). J Am Coll Cardiol. 2006;50:562-
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