BACKGROUND: Cardiac contractility modulation (CCM) in heart failure (HF) patients with reduced ejection fraction (HFrEF) is an innovative therapy which may contribute to increased exercise capacity and quality of life and reduced hospitalizations. With speckle-tracking echocardiography and global longitudinal strain (GLS), changes in myocardial function can be detected with greater sensitivity than conventional approaches for measuring diastolic and systolic function, including left ventricular ejection fraction. We aim to analyze the usefulness of GLS in detecting improvement in systolic function and response to CCM treatment.
METHODS: We studied 5 patients with CCM referred to our outpatient cardiology clinic. All patients underwent complete echocardiography with evaluation of GLS and ejection fraction. Follow-ups were performed at 1, 3, and 6 months.
RESULTS: All patients were men (mean age 65.3±15.7 yrs). Mean baseline ejection fraction was 37.1±9.3%, mean GLS was 7.7±3.1%, and patients had mild-to-moderate left ventricular enlargement (mean indexed telediastolic volumes 101.4±8.7 ml/m2). Follow-up performed at the first month showed values similar to baseline values. Between the third and sixth months, a non-significant improvement in ejection fraction and GLS was recorded (EF 40.75±9.6% p=0.51; GLS 8.9±4.2 p=0.62). Indexed telediastolic volumes were reduced (101.4±9.3 ml/m2 vs 89.5±7.4 ml/m2 p=0.05).
CONCLUSIONS: CCM therapy seems to be useful in achieving volumetric remodeling in patients with HFrEF. GLS assessment may be useful in detecting improvement in systolic function. Further studies with larger samples and longer follow-up are needed to confirm these results.