Cardiac Rehabilitation Improves Fitness in Patients With Subclinical Markers of Cardiotoxicity While Receiving Chemotherapy

A RANDOMIZED CONTROLLED STUDY

Abstract

Purpose: 

Heart failure (HF) due to cardiotoxicity is a leading non–cancer-related cause of morbidity and mortality in cancer survivors. Cardiac rehabilitation (CR) improves cardiorespiratory fitness (CRF) and reduces morbidity and mortality in patients with HF, but little is known about its effects on cardiotoxicity in the cancer population. The objective of this study was to determine whether participation in CR improves CRF in patients undergoing treatment with either doxorubicin or trastuzumab who exhibit markers of subclinical cardiotoxicity.

Methods: 

Female patients with cancer (n = 28: breast, n = 1: leiomyosarcoma) and evidence of subclinical cardiotoxicity (ie, >10% relative decrease in global longitudinal strain or a cardiac troponin of >40 ng·L⁻¹) were randomized to 10 wk of CR or usual care. Exercise consisted of 3 d/wk of interval training at 60-90% of heart rate reserve.

Results: 

Cardiorespiratory fitness, as measured by peak oxygen uptake (V˙o_2peak), improved in the CR group (16.9 + 5.0 to 18.5 + 6.0 mL∙kg⁻¹ ∙min⁻¹) while it decreased in the usual care group (17.9 + 3.9 to 16.9 + 4.0 mL∙kg⁻¹ ∙min⁻¹) (P = .009). No changes were observed between groups with respect to high-sensitivity troponin or global longitudinal strain.

Conclusion: 

This study suggests that the use of CR may be a viable option to attenuate the reduction in CRF that occurs in patients undergoing cardiotoxic chemotherapy. The long-term effects of exercise on chemotherapy-induced HF warrant further investigation.

In Brief

We sought to determine whether cardiac rehabilitation (CR) improves cardiorespiratory fitness and markers of chemotherapy-related cardiotoxicity. Patients with cancer and evidence of cardiotoxicity were randomized to CR or usual care. Peak oxygen uptake improved with CR. No changes in cardiac markers were observed. This study supports CR for patients undergoing cardiotoxic chemotherapy.