No effects of cardiac resynchronization therapy and right ventricular pacing on the right ventricle in patients with heart failure and atrial fibrillation.

BACKGROUND The right ventricle (RV) function is crucial in heart failure with reduced ejection fraction (HFrEF), especially in patients with atrial fibrillation (AF). Aims. To assess the RV structure and function in patients with HFrEF, permanent atrial fibrillation (AF), cardiac resynchronization therapy (CRT) and RV pacing (RVp) with two- and three-dimensional echocardiography. Methods. Patients with ischemic HFrEF (NYHA II-III; LVEF ≤40%) were enrolled. The studied groups were: sinus rhythm (SR, control); AF and no implanted devices - AF/0; AF and CRT - AF/CRT; AF and RVp - AF/RVp. Two- and three-dimensional echocardiographic parameters of RV structure and function were analyzed in study groups. Results. The study included a group of 126 patients: n = 32 with SR, n = 28 with AF/0, n = 25 with AF/CRT and n = 41 with AF/RVp. Results were worse in AF groups than in SR: right ventricular ejection fraction, %, mean (SD): SR - 48.2 (7.5), AF/0 - 36.5 (6.5), AF/CRT - 38.3 (7.6), AF/RVp - 37.1 (7.7), p < .001. Other parameters lower in AF groups than in SR were: RV end-systolic volume, longitudinal strain of the free wall and tricuspid lateral annular systolic velocity. There were no differences between groups with AF and CRT and RV pacing in other analyzed parameters between AF groups and SR. Conclusions. In heart failure with reduced left ventricular ejection fraction and atrial fibrillation right ventricular pacing and cardiac resynchronization therapy were not associated with modified right ventricular function. Further prospective studies are needed to evaluate prognostic significance of these results.