Abstract
PURPOSE: We evaluated left ventricular contractility during upright isometric exercise, in heart transplant recipients (HTRs) and in healthy controls, using ejection fraction and end-systolic pressure/volume ratio indexes.
METHODS: Fifteen healthy men (40 +/- 13 years) and 10 HTRs (42 +/- 12 years) underwent dead lift (DL) test at 30% of maximal effort for 3 minutes. Echocardiographic variables were measured during the final 45 seconds.
RESULTS: During DL test, HTRs were significantly different (P < .01) from controls in all parameters except end-diastolic volume. DL test had lower mean values of ejection fraction (49.9% +/- 8.3% vs 67.0% +/- 4.3%, respectively) and left ventricular end-systolic pressure/volume ratio (3.5 +/- 0.7 vs 5.5 +/- 1.2, respectively) whereas higher values of end-systolic volume (51.0 +/- 9.4 mL vs 34.1 +/- 5.3 mL, respectively). Importantly, an intergroup effect was found in end-systolic pressure/volume ratio, further signifying differential response of HTRs. End-systolic pressure/volume ratio increased consistently (P < .001) in both groups, whereas the overall main effect of ejection fraction response was not significant.
CONCLUSIONS: Left ventricular function during upright isometric exercise displays differential pattern of response in HTRs in comparison with healthy controls. However, cardiac contractility in HTRs remained stable at peak systolic blood pressure produced by the isometric DL exercise. Results suggest that both ejection fraction and end-systolic pressure/volume ratio indexes can be used for assessment of ventricular function in patients after heart transplantation.