Cardiac resynchronization therapy and atrial fibrillation: the importance of atrioventricular ablation

To study long-term efficacy of cardiac resynchronization therapy (CRT) in patients with chronic heart failure, CRT was performed in 151 patients aged 55.4±10.3 years (21-76 years) and mean functional class by NYHA of 3.2±0.4. The predominating etiology of chronic heart failure was nonischemic cardiomyopathy (n=98, 65%). The QRS complex width was 183±32 ms (146-240 ms). The clinical examination of study subjects was performed after one, three, six, 12, 24, and 36 months following implantation of CRT device. The follow-up period lasted for 35.7±4.3 months. According to data, recorded by the implanted CRT devices, pacing rates in patients with AF without AV nodal ablation and patients with AF after AV nodal ablation were 66.7±2.6% and 95.3±11.7%, respectively. Majority of nonresponders did not have AV nodal ablation. Finally, CRT had beneficial effects on LVEF, NYHA Class, and quality of life in AF patients with AV nodal ablation. CRT efficacy depended on amount of ventricular capture beats in this category of patients.