Short-term effects of sinus rhythm restoration in patients with lone atrial fibrillation: a hormonal study.

It is well known that atrial fibrillation can lead to heart failure, and is attributed to rapid ventricular rate (tachycardia-induced cardiomyopathy). Some recent studies suggest the possible existence of an intrinsic left-ventricular factor related to atrial fibrillation, irrespective of other elements. In order to demonstrate the implication of this factor, we measured B-type Natriuretic Peptide, known as a functional marker of left-ventricular dysfunction, in 40 consecutive patients with chronic non-valvular atrial fibrillation, with low ventricular rate and absence of clinical heart failure or echocardiographic left-ventricular dysfunction. In all patients, Brain Natriuretic Peptide (BNP) plasma level was high and dramatically decreased 24 h after external electrical cardioversion (61.4 pg/ml before cardioversion, 23.5 pg/ml 1 day after cardioversion, P<0.002). Our study demonstrates that atrial fibrillation, in absence of high ventricular rate, induces an asymptomatic cardiac alteration that is not detectable by echocardiography.