OBJECTIVE
To evaluate clinical efficacy of cardiac contractility modulation (CCM) in patients with chronic heart failure (CHF) and various forms of atrial fibrillation (AF).
MATERIAL AND METHODS
The study included 160 CHF patients with reduced left ventricular ejection fraction (LVEF) and AF. Patients were divided into 2 groups: CCM group (n=80) — implantation of Optimizer Smart device under optimal therapy, control group (n=80) — optimal therapy only. In each group, analysis was carried out depending on the form of AF. Initially and after 12 months of follow-up, 12 lead electrocardiography, transthoracic echocardiography, 24-hour ECG monitoring, NT-proBNP analysis, 6-minute walk test were performed in all patients. We also assessed the quality of life using the Minnesota Living with Heart Failure Questionnaire.
RESULTS
We confirmed significant clinical efficacy of CCM therapy considering CHF class decrease (p=0.001) after 12 months, improvement in 6-minute walk test (p=0.001) and MLHFQ score decrease (p=0.001). In the CCM therapy group, patients with paroxysmal AF showed a significant decrease in concentration of NT-proBNP after 12 months (p=0.003). In the same group, we observed less left ventricular end-diastolic (p=0.009) and end-systolic volumes (p=0.001), as well as significant decrease in LA volume (p=0.004). There was an improvement in myocardial contractility (LVEF increment) in patients with paroxysmal and permanent AF after Optimizer Smart device implantation compared to the control group (p=0.001). QRS width did not significantly increase under CCM therapy in both paroxysmal and permanent AF. In the control group, patients with permanent AF had significant prolongation of QRS (p=0.045). In the CCM therapy group, the total number of ventricular premature beats per day did not increase regardless the form of AF, and significant decrease in AF paroxysms was revealed (p=0.038). In the same group, patients with permanent AF had significant decrease in the incidence of non-sustained ventricular tachycardia (p=0.011). In the control group, patients with permanent AF had significantly higher incidence of non-sustained ventricular tachycardia after 12 months (p=0.005).
CONCLUSION
Our data demonstrate that CCM therapy improves the functional state and quality of life, promotes reverse LV remodeling and does not contribute to various cardiac arrhythmias.
