Аннотация
Introduction: Cardiac resynchronization therapy (CRT) has emerged as the predominant electrical treatment strategy for patients on pharmacological therapy who present chronic heart failure (CHF) with low ejection fraction. The objective of this study was to investigate whether cardiac resynchronization therapy improved morbidity among patients with heart failure. Materials and methods: This follow-up study enrolled 70 adult patients undergoingCRT device implantation. Inclusion criteria was presence of heart failure (CHF New-York Heart Association functional class III, IV) and left bundle branch block. We performed measurements of cardiac contraction parameters by echocardiography (on the Vivid 7 GE) at the beginning of the study and 12, 24 month after CRT device implantation. All patients received beta-blockers, angiotensin-converting enzyme inhibitors/angiotensin II receptor antagonists, diuretics (including aldosterone antagonists), antiplatelet agents, anticoagulants and HMG-CoA Reductase Inhibitors (up to indications). Results: We observed significant increase inejection fraction 12 months after CRT implantation (28.3 ± 0.9% to 37.9 ± 0.9%, p < 0.0001 vs 0) same as after 24 months. There was no significant difference in left ventricle end diastolic dimension and mean pulmonary artery pressure. Intraventricular conduction delay significantly decreased in 12 month after CRT device implantation (238 ± 23.7 ms, p < 0.05), but after 24 months it increased to the same value as before CRT device implantation (271.8 ± 12.41 ms). Interventricular conduction delay showed significant and stable decrease after CRT device implantation (29.7 ± 5.6 ms for 12 month and 27.5± 4.3 ms for 24 month compared with 0 point 59.6 ± 4.9 ms, p < 0.005). We observed significant and stable trend to increase in diastolic filling time (44.7 ± 0.98 for 12 month, 46.08 ± 0.7 for 24 month vs 40.85 ± 0.99 at 0 point, p < 0.05). Positive changes in the parameters of central hemodynamics were accompanied by improvement of the clinical state of patients (reduction in dyspnea, increased tolerance to physical exercise). Conclusion: Our results suggest that implantation of СRT device for patients with heart failure helps to improve contraction and relaxation of heart muscles, but has no positive effect on the end diastolic dimension of left ventricle and mean pulmonary artery pressure.