Exercise-Based Cardiac Rehabilitation: Impact on Myocardial Function measured by Global Longitudinal Strain

Abstract

Measures of cardiovascular (CV) health and function are improved by exercise. However, it might be challenging to determine the short-term efficacy of an exercise intervention when conventional metrics steadily improve. Reductions in left ventricular global longitudinal strain (LVGLS) are a powerful predictor of future cardiac dysfunction and death. LVGLS is a very sensitive cardiac imaging tool that can identify myocardial dysfunction before more conventional assessments. Because of its sensitivity, LVGLS may provide a practical way to monitor the short-term impact of an exercise intervention on CV function, giving practitioners valuable data to enhance patient care in exercise environments. It's unknown, nevertheless, how exercise affects LVGLS. This systematic review and meta-analysis aimed to determine the effect exercise has on LVGLS across a range of populations. Included studies assessed LVGLS pre–post an exercise intervention (minimum 2 weeks) in adults 18 years and over, and were published in English from 2000 onwards. Study-level random-effects meta-analyses were performed using Stata (v16.1) to calculate summary standardized mean differences (SMD) and 95% confidence intervals (CI). 39 studies met selection criteria, with 35 included in meta-analyses (1765 participants). In primary analyses, a significant improvement in LVGLS was observed in populations with CV disease (SMD=0.59; 95% CI 0.16–1.02; p=0.01), however, no significant effect of exercise was observed in CV risk factor and healthy populations. In populations with CV disease, LVGLS could be used as an early biomarker to determine the effectiveness of an exercise regime before changes in other clinical measures are observed.