Current Clinical Status of Nitroglycerin and Other Nitrates

Angina pectoris constitutes the only currently approved indication for nitroglycerin therapy. Recent demonstrations that intravenously administered vasodilators can quickly improve the hemodynamics of left ventricular failure1-3have led to widespread interest in the nitrates as potentially useful agents for long-term vasodilator therapy.4-6This has led to a rekindling of questions concerning the pharmacological efficacy of nonparenterally given nitrates and the use of hypotensive agents in acute myocardial infarction. Newer issues have also arisen regarding the mechanism of action of nitrates and their long-term effects in congestive heart failure. Controlled studies using objective hemodynamic criteria have clearly shown that orally administered nitrates are pharmacologically active.4-6It is likely that the high doses employed in these trials at least partially explain the departure from earlier animal studies that demonstrated lack of effect of orally administered nitrates due to hepatic biotransformation.7Whereas the hemodynamic efficacy of orally given nitrates