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

Objectives: To describe the mid-term clinical and functional cardiac contractility modulation therapy (CCM) recipients in an urban population with heart failure.

Background: 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.

Methods: 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.

Results: Mean age and follow-up time was 63 ± 10 years and 1.4 ± 0.8 years, 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 ± 14.8 days/year; p = 0.96; after exclusion, 3.8 ± 4.7 vs. 1.1 ± 1.9 days/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.

Conclusion: In an observational cohort, CCM therapy resulted in improvement in NYHA class, hospitalizations, systolic and diastolic function, and weight.