Effect of telmisartan on paroxysmal atrial fibrillation recurrence in hypertensive patients with normal or increased left atrial size

BACKGROUND: Hypertension is the most prevalent and potentially modifiable risk factor for atrial fibrillation (AF). In a previous secondary prevention study, the authors observed that the angiotensin II receptor blocker telmisartan was more effective than the calcium channel blocker amlodipine in preventing AF relapse in hypertensive patients with normal atrial size. HYPOTHESIS: Telmisartan may be more effective than amlodipine in preventing AF recurrence in hypertensive patients with paroxysmal AF and normal or increased left atrial dimension (LAD). METHODS: The authors assigned 378 mild hypertensive outpatients in sinus rhythm, but with ≥2 episodes of AF in the previous 6 months, to 1 of 2 groups. Group 1 comprised patients with LAD <40 mm in females and <45 mm in males. Group 2 comprised patients with LAD >40 mm and <45 mm in females and >45 mm and <50 mm in males. In both groups, patients were randomly treated with telmisartan or amlodipine for 1 year. RESULTS: Systolic and diastolic blood pressure were similarly reduced by telmisartan and amlodipine in both groups. The AF recurrence rate was significantly lower in the telmisartan-treated patients than in the amlodipine-treated patients in both group 1 (12 vs 39, P < 0.01) and group 2 (40 vs 59, P < 0.05). Under telmisartan, the AF recurrence rate was significantly lower in group 1 than in group 2 (12.9% vs 42.1%, P < 0.05). Time to a first AF relapse was significantly longer with telmisartan than with amlodipine in both group 1 (176 ± 94 days vs 74 ± 61 days, P < 0.05) and group 2 (119 ± 65 days vs 38 ± 35 days, P < 0.05)