Mid-term clinical outcomes and cardiac function in patients receiving cardiac contractility modulation.

Abstract

To describe the mid-term clinical and functional cardiac contractility modulation therapy (CCM) recipients in an urban population with heart failure. CCM is a non-excitatory electrical therapy for patients with systolic heart failure with NYHA class III symptoms and ejection fraction (EF) 25-45%. How CCM affects a broad range of clinical measures, including diastolic dysfunction (DD) and weight change, is unexplored. We reviewed 31 consecutive patients at our center who underwent CCM implant. NYHA class, hospitalizations, ejection fraction (EF), diastolic function, and weight were compared pre- and post-CCM implant. Mean age and follow-up time was 63 ± 10years and 1.4 ± 0.8years, respectively. Mean NYHA class improved by 0.97 functional classes (p < 0.001), and improvement occurred in 68% of patients. Mean annualized hospitalizations improved (0.8 ± 0.8 vs. 0.4 ± 1.0 hospitalizations/year, p = 0.048), and after exclusion of a single outlier, change in annualized days hospitalized also improved (total cohort 3.8 ± 4.7 vs. 3.7 ± 14.8days/year; p = 0.96; after exclusion, 3.8 ± 4.7 vs. 1.1 ± 1.9days/year, p < 0.001). Mean EF improved by 8% (p = 0.002), and among those with DD pre-CCM, mean DD improvement was 0.8 "grades" (p < 0.001). Mean weight change was 8.5 pounds lost, amounting to 4% of body weight (p = 0.002, p = 0.002, respectively), with 77% of patients having lost weight after CCM. Five patients (16%) experienced procedural complications; incidence skewed toward early implants. In an observational cohort, CCM therapy resulted in improvement in NYHA class, hospitalizations, systolic and diastolic function, and weight.