Effect of percutaneous transluminal coronary angioplasty on exercise ventilation in patients with coronary artery disease and normal left ventricular function.

We evaluated the ventilatory response to exercise before and after percutaneous transluminal coronary angioplasty (PTCA) in 22 patients with coronary artery disease (CAD) and normal left ventricular systolic function to determine the effect of exercise-induced myocardial ischemia on the ventilatory response. Subjects performed a symptom-limited maximal ergometer exercise test in the sitting position. The ventilatory response was evaluated in terms of the slopes of minute ventilation (VE) and carbon dioxide production (VCO2) during exercise (slope 1 and slope 2, defined as below and above the respiratory compensation threshold, respectively). Slope 1 of the correlation between (VE) and (VCO2) was significantly greater in patients with CAD (27.3 +/- 2.6) than in the age-matched control group (23.7 +/- 2.6; p < 0.01). Slope 2 was also significantly greater in patients (41.0 +/- 4.8) than in the control group (29.7 +/- 2.9; p < 0.01). Slope 1 of the correlation between (VE) and (VCO2) decreased significantly in the 14 patients in whom PTCA was successful but did not decrease in the 8 patients in whom PTCA failed. Our results suggest that myocardial ischemia increases exercise ventilation in patients with CAD and normal left ventricular systolic function and that its effect is reversible.