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 per cutaneous transluminal coronary angioplasty (PTCA) in 22 patients with coronary artery disease (CAD) and normal left ventricular systolic fu nction to determine the effect of exercise-induced myocardial ischemia on the ventilatory response. Subjects performed a symptom-limited max imal ergometer exercise test in the sitting position. The ventilatory response was evaluated in terms of the slopes of minute ventilation (V overdot(E)) and carbon dioxide production (VoverdotCO(2)) during exerc ise (slope 1 and slope 2, defined as below and above the respiratory c ompensation threshold, respectively). Slope 1 of the correlation betwe en (Voverdot(E)) and (VoverdotCO(2)) was significantly greater in pati ents 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 patie nts (41.0 +/- 4.8) than in the control group (29.7 +/- 2.9; p < 0.01). Slope 1 of the correlation between (Voverdot(E) and (VoverdotCO(2)) d ecreased significantly in the 14 patients in whom PTCA was successful but did not decrease in the 8 patients in whom PTCA failed. Our result s suggest that myocardial ischemia increases exercise ventilation in p atients with CAD and normal left ventricular systolic function and tha t its effect is reversible.