Effects of perhexiline on coronary hemodynamic and myocardial metabolic responses to tachycardia

Abstract

Coronary hemodynamic and myocardial metabolic responses before and after perhexiline administration were studied in 21 patients with coronary heart disease during pacing induced angina pectoris. Perhexiline increased the threshold to tachycardia induced angina pectoris in 16 of the 21 patients (HR 123 ± 3 to 134 ± 3 beats/min, P < 0.01). Anaerobic myocardial lactate extraction was reduced by -6.1 ± 6.3 to 10.7 ± 4% after perhexiline, although lactate extraction declined in four patients and ST segment depression was not significantly changed. Myocardial oxygen extraction was enhanced, 64 ± 2 to 69 ± 2% (P < 0.05). Coronary flow as reflected by coronary sinus blood flow was not altered (165 ± 24 to 173 ± 26 cc/min) as left ventricular oxygen utilization was increased (18.9 ± 4 to 20.9 ± 4 ml/min, P < 0.05). These findings are interpreted to indicate decreased myocardial ischemia in certain patients on perhexiline.