CONGRESS ABSTRACT

Cardiac contractility modulation (CCM) is an innovative therapeutic strategy for chronic heart failure, particularly in patients with reduced or moderately impaired left ventricular ejection fraction. Unlike conventional therapies that primarily reduce hemodynamic load or modulate neurohormonal pathways, CCM directly enhances myocardial contractile function. The delivery of high-voltage biphasic electrical impulses during the absolute refractory period aims to improve contractile efficiency without significantly affecting heart rate or rhythm. Preclinical and clinical studies have shown favorable effects on cellular and molecular mechanisms, including calcium handling, gene expression, and oxidative stress reduction. We report data from 16 patients (11 males; mean age 71 ± 10.9 years) who underwent CCM implantation at our center since February 2023. All patients were carriers of an implantable cardioverter-defibrillator. Heart failure etiology was ischemic cardiomyopathy in ten patients, valvular heart disease in two, and dilated cardiomyopathy in four. All patients had a history of heart failure–related hospitalizations, and two experienced ICD shocks within the previous six months. Patients were classified as high risk (NYHA class III, n=10; class IV, n=6), with a mean left ventricular ejection fraction (LVEF) of 28 ± 6.8% and mean pulmonary artery systolic pressure (PASP) of 43.1 ± 13.9 mmHg. CCM implantation was successfully performed in all cases. Patients were followed on an outpatient basis and reassessed at 3, 6, and 12 months. At follow-up, mean LVEF increased to 30.1 ± 8.2%, while mean PASP decreased to 37.2 ± 12.8 mmHg. Improvement of at least one NYHA class was observed in four patients (data unavailable for three). Notably, 62.5% of patients experienced no heart failure–related hospitalizations during the 12 months following implantation. Despite the limitations of a small sample size, our single-center experience aligns with existing literature and demonstrates clinically meaningful improvements in functional status, cardiac performance, and hospitalization burden in patients with moderate-to-severe left ventricular systolic dysfunction treated with CCM.