RESUMEN
We have previously shown that transdermal nitroglycerin may induce an increase in the activity of the adrenergic and the renin-angiotensin-aldosterone systems (SRAA) in patients with chronic stable angina pectoris (SA); when the activation of these systems is more pronounced, the antianginal effect of this drug seems to be reduced. The aim of this study was to evaluate the antianginal efficacy of transdermal nitroglycerin administration (TTS-NG 10 mg.24 h-1) in combination with an ACE inhibitor without sulphydryl groups (BNZ, benazepril 10 mg b.i.d.) in respect to placebo, or to TTS-NG or BNZ administered as monotherapy. Twenty-four patients (21M, 3F) were admitted to this multicentre, randomized, double-blind, latin square, placebo-controlled study. Patients received all the treatments (placebo, TTS-NG, BNZ and BNZ + TTS-NG) each for one week; at the end of each week patients performed two exercise tests 2 and 22 h post-dosing. Two hours post-dosing, exercise duration at 1 mm ST depression was significantly increased in respect to placebo during TTS-NG (P < 0.05) and TTS-NG + BNZ (P < 0.05) treatments. Two hours post-dosing, exercise duration at peak exercise was also increased in respect to placebo during TTS-NG (P < 0.05) and TTS-NG + BNZ (P < 0.05); 22 h post-dosing the increase in exercise duration was significant only during TTS-NG + BNZ treatment (P < 0.05) in respect to placebo, but not during TTS-NG given alone. Rate-pressure product at 1 mm ST depression was significantly increased 2 h post-dosing during TTS-NG treatment (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)