The relationship between exercise capacity and left ventricular function has been evaluated in 35 patients with acute myocardial infarction (34 males and 1 female; mean age 55.5 ± 7.1 years). Single photon emission computed tomography (SPECT) was used to measure left ventricular function in the acute phase (4.9 ± 2.2 days after onset) and the chronic phase (188.5 ± 22.9 days after onset). More than 10% left ventricular dilatation from the acute phase to the chronic phase was defined as remodeling (RM) and the subjects were divided into 2 groups: RM and non-RM. Cardiopulmonary exercise testing was performed at 1 month (1M), 3 months (3M) and 6 months (6M) after onset. In the RM group, anaerobic threshold (AT) and peak oxygen uptake (Peak ) did not change significantly. In the non-RM group, AT was 15 ± 1 (ml/min/Kg) at 1M, 16 ± 2 at 3M and 18 ± 4 at 6M. Peak was 26 ± 3 (ml/min/Kg) at 1M, 30 ± 2 at 3M and 32 ± 3 at 6M. Both parameters in the chronic phase increased significantly compared with those at 1M (p<0.002 and p<0.0001). Thus, change in exercise capacity would correlate with change in left ventricular function.
Keywords: acute myocardial infarction; cardiopulmonary exercise testing; myocardial scintigraphy.