Congestive heart failure with and without atrial fibrillation - different patient populations?

Heart failure (HF) and atrial fibrillation (AF) are common comorbid conditions in hospitalised patients. AF may occur when left ventricular (LV) systolic function deteriorates. The aim was to compare HF patients with AF to patients in sinus rhythm (SR).

Echocardiography and a cardiopulmonary exercise test were performed in 67 patients with HF. Peak VO(2) was determined, as were LV-mass, enddiastolic, endsystolic volume indices (EDVI, ESVI), and ejection fraction (EF).

EF tended to be higher in AF compared to SR patients (39+/-10 vs. 31+/-10%), LV volume indices were smaller (ESVI:35+/-19 vs. 59+/-25 ml/m(2), p<0.0001, EDVI:56+/-24 vs. 83+/-29 ml/m(2), p<0.001). LV hypertrophy was prevalent (59% vs. 63%) and concentric hypertrophy tended to be more common with AF (50% vs. 21%). Peak VO(2) was similarly reduced in AF and SR (11.4+/-3.2 vs. 12.1+/-4.3 ml/kg*min).

HF patients with AF compared to SR tend to have smaller LV volumes, less compromised systolic function and more frequent LV concentric hypertrophy. Our study supports the concept that AF in HF indicates a different patient population rather than an effect of progressive LV systolic dysfunction.