In patients with coronary heart disease (CHD), individualized exercise training (ET) programs are strongly recommended to optimize peak oxygen uptake VO2peak) improvement and prognosis. However, the cardiac hemodynamic factors responsible for a positive response to training remain unclear.

The aim of this study was to compare cardiac hemodynamic changes after an ET program in responder (R) versus non-responder (NR) CHD patients.

A total of 72 CHD patients completed a 3-month ET program, and were assessed by cycle ergometer cardiopulmonary exercise test (CPET: VO2peak assessment) with impedance cardiography (ICG) for hemodynamic measurements before and after training. Cardiac hemodynamics (e.g. CO, CI, SV, ESV, EDV, SVR) were measured by ICG during CPET. The R and NR group were classified using the median change in VO2peak (> the median for R and ≤ the median for NR).

In the R group, VO2peak (+17%, P<0.001), CO, CI, SV and HR increased by 17%, 17%, 13% and 5%, respectively (P<0.05) after the training program. In the NR group, VO2peak, CO, CI and SV increased by 0.5%, 5%, 8% and 6%, respectively (P<0.01). The SVR decreased in both groups (−19% in R and -11% in NR, P<0.001) (Figure 1).

Among CHD patients, the R group showed a better improvement in peak cardiac output via an increase of peak stroke volume and heart rate, and a reduced systemic vascular resistance than the NR group. Different cardiac phenotypes adaptations and clinical individual responses were identified in CHD patients according to aerobic fitness responder's status.