Refractory ergonovine-induced coronary vasospasm: importance of intracoronary nitroglycerin.

Recent experience has suggested that the ergonovine maleate test is a safe procedure for the diagnosis of variant angina pectoris, because ergonovine-induced coronary vasospasm has generally been reversible by sublingual nitroglycerin. This report describes five cases of ergonovine-induced coronary vasospasm that were refractory to sublingual nitroglycerin. Four of these patients had cardiac arrest. In two patients the vasospasm was responsive to intracoronary nitroglycerin administration. Three patients died as a reuslt of the test. The two survivors differed from the nonsurvivors in the total dose or ergonovine given (0.1 and 0.15 mg versus 0.17, 0.3 and 0.3 mg, respectively) and in the method of administration of ergonovine. The survivors were given serial doses of 0.05 mg each whereas the three nonsurvivors received either larger initial doses (0.1 followed by 0.07 mg) or progressive incremental doses (0.05, 0.1 and 0.15 mg serially). Sublingual nitroglycerin, given to all five patients, and intravenous nitroglycerin, given to three of the five, were ineffective in reversing vasospasm. Intracoronary nitroglycerin favorably altered the course of the survivors. Thus, the ergonovine maleate test is not benign and may cause severe coronary vasospasm that is unresponsive to sublingual and intravenous nitroglycerin, but may be reversed by intracoronary nitroglycerin.