Nitroglycerin unstable angina

Organic nitrates (and nitrites) are simple nitric and nitrous acid esters of alcohols. They differ in their volatility for example, isosorbide dinitrate is solid at room temperature, nitroglycerin is only moderately volatile, whereas amyl nitrate is extremely volatile. These compounds cause a rapid reduction in myocardial oxygen demand followed by rapid relief of symptoms. They are effective in stable and unstable angina, as well as Prinzmetal s or variant angina pectoris. 

Diodati J, Theroux P, Latour JG et d (1990) Effects of nitroglycerin at therapeutic doses on platdet aggregation in unstable angina pectoris and acute myocardial infarction. Am J Cardiol 66 683-688. 

Horowitz JD, Henry CA, Syrjanen ML et al (1988) Combined use of nitroglycerin and N-acetylcysteine in the management of unstable angina pectms. Circulation 77 787-794. 

Other organs Nitrates relax the smooth muscle of the bronchi, gastrointestinal tract, and genitourinary tract, but these effects are too small to be clinically useful. Intravenous nitroglycerin (sometimes used in unstable angina) reduces platelet aggregation. There are no significant effects on other tissues. 

More of the patients who received the active product than those who received placebo reported complete resolution of angina (30% vs. 13%) and no nitroglycerin use (43% vs. 17%) at 8 weeks. In addition, the incidence of worsening/unstable angina and revascularation by coronary artery bypass grafting or angioplasty at 12... 

Its properties resemble those of the preceding substance. One molecule of nitric acid is readily lost by the compound, which is then transformed into triethanolamine trinitrate. The latter is also unstable and inclined to undergo decomposition. Diphosphoric salt of the trinitric ester was claimed to be an effective remedy against angina pectoris, instead of nitroglycerine. 

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