PREDICTORS OF PRIMARY ATRIAL-FIBRILLATION AND CONCOMITANT CLINICAL AND HEMODYNAMIC-CHANGES IN PATIENTS WITH CHRONIC HEART-FAILURE - A PROSPECTIVE-STUDY IN 344 PATIENTS WITH BASE-LINE SINUS RHYTHM

Objectives. This study investigated the incidence, predisposing factor s and significance of the onset of atrial fibrillation (AF) in patient s with chronic congestive heart failure (CHF). Background. The associa tion between CHF and AF is well documented, but the factors that predi spose to the onset of the arrhythmia and its impact remain controversi al. Methods. We prospectively followed up 344 patients with CHF and si nus rhythm (SR). Over a period of 19 +/- 12 months (mean +/- SD), 28 p atients developed atrial fibrillation (AF), which became chronic in 18 . Results. At baseline, no differences were found in any clinical and hemodynamic variables between patients who developed chronic AF and th ose who did not. Reversible AF occurring during follow-up and lower mi tral flow velocity at atrial contraction as detected at the last evalu ation in SR were independent predictors of the subsequent development of chronic AF. When AF occurred, New York Heart Association functional class worsened (from 2.4 +/- 0.5 to 2.9 +/- 0.6, p = 0.0001), peak ex ercise oxygen consumption declined (from 16 +/- 5 to 11 +/- 5 ml/kg pe r min, p = 0.002), cardiac index decreased (from 2.2 +/- 0.4 to 1.8 a 0.4, p 0.0008), and mitral and tricuspid regurgitation increased (from grade 1.8 +/- 1.1 to grade 2.4 +/- 1.4, p = 0.0001 and from grade 1.0 +/- 1.2 to grade 1.8 +/- 1.2, p = 0.001, respectively). Systemic thro mboembolism occurred in 3 of the 18 patients with AF. Nine of 18 patie nts died after AF, and the occurrence of AF was a predictor of major c ardiac events. Conclusions. In patients with CHF, reversible AF and re duction of left atrial contribution to left ventricular filling predic t the subsequent development of chronic AF. The onset of AF is associa ted with clinical and hemodynamic deterioration and may predispose to systemic thromboembolism and poorer prognosis. (C) 1998 by the America n College of Cardiology.