ENOXIMONE IN CHRONIC STABLE ANGINA - A DOUBLE-BLIND PLACEBO-CONTROLLED CROSS-OVER TRIAL

Enoximone, a phosphodiesterase inhibitor (PDEI), has both positive ino tropic and vasodilatory properties. We examined the effect of a single oral dose of enoximone as compared with placebo on myocardial ischaem ia and global left ventricular (LV) function using both exercise ECG a nd Doppler measurements of aortic blood flow, respectively. Twenty pat ients (16 men, 4 women) with a mean age of 59 years and stable angina were studied. Total exercise duration was significantly longer after e noximone as compared with placebo treatment, with a mean difference of 22.8 s (p = 0.003). Times (mean +/- SD) to onset of angina and develo pment of significant ST-segment decrease were similar after placebo (4 54 +/- 101 and 352 +/- 155 s, respectively) or enoximone (500 +/- 155 and 413 +/- 192 s, respectively), although both showed trends in favou r of enoximone. As compared with placebo, significantly higher heart r ate (HR) was measured for enoximone both at rest (75 +/- 18 vs. 90 +/- 22 beats/min, p < 0.01) and on recovery from exercise (81 +/- 18 vs. 89 +/- 19 beats/min, p < 0.05). Enoximone had no significant effect on systolic or diastolic blood pressure (SBP, DBP) or rate-pressure prod uct (RPP) generated at rest or during exercise. Changes in both accele ration and velocity of aortic blood flow during exercise were similar after administration of enoximone or placebo. We showed that a single oral dose of enoximone is well tolerated in patients with ischaemic he art disease, improving both exercise capacity and favourably influenci ng ST-segment changes with no increase in adverse events or significan t haemodynamic disturbances.