Slower Heart Rates for Healthy Hearts

Abstract

The management of atrial fibrillation, even in the modern era, remains complex and challenging. Preventing atrial fibrillation occurrence by identifying and favorably improving modifiable risk factors thus assumes great importance. It is well known that hypertension and resultant structural heart disease contributes significantly to the incidence of atrial fibrillation.1,2 The Losartan Intervention For End point reduction in hypertension (LIFE) study thus far has shown us that angiotensin-receptor blockade and reduction in left ventricular hypertrophy, irrespective of blood pressure–lowering, reduces the incidence of new-onset atrial fibrillation.1,3 Article see p 337 In recent years, accumulating evidence has linked high resting sinus heart rates (HR) directly and indirectly to adverse cardiovascular outcomes.4,5 Epidemiological studies show resting HR to be an independent predictor of cardiovascular and all-cause mortality in general population as well as in hypertensive patients.6 The cardiovascular benefits offered by β-blockade in coronary artery disease and heart failure have, in part, been attributed to β-blocker–mediated HR reduction.7,8 Other studies have linked high baseline HR to the development of hypertension, to the progression of coronary artery disease, and to the triggering of myocardial infarction, ventricular dysfunction, and ventricular arrhythmias.6,9–11 In this issue of Circulation: Arrhythmia and Electrophysiology , Okin and colleagues12 examines the relationship of HR changes over time on risk of atrial fibrillation in hypertensive patients as part of the LIFE study. In this post hoc analysis of the prospective LIFE study, 8828 hypertensive patients with left ventricular hypertrophy by ECG but without a history of atrial fibrillation were followed for a mean of 4.7±1.1 years. New onset atrial fibrillation was determined by 12-lead ECG performed on an intermittent, infrequent basis (at baseline, 6 months, and yearly thereafter). Hypertension was treated with losartan or atenolol. Using a variety of analyses, higher in-treatment HR on serial …