Nitrate tolerance as a possible cause of multidrug-resistant coronary artery spasm.

Coronary spasm can usually be controlled by administration of Ca antagonists. However, there are some cases of coronary spasm whose attacks cannot be controlled even with large doses of Ca antagonist and/or its combination with nitrates. Here we describe the case of a 41-year-old man whose attacks of coronary spasm were resistant to the combined administration of nitrates, Ca antagonists, and a statin. The attacks were alleviated and disappeared after withdrawal of nitrates and recurred after readministration of a nitroglycerin patch. The involvement of nitrate tolerance in the pathogenesis of multidrug resistant coronary spasm was revealed and its implication discussed.