The smoking of crystal methamphetamine, or "ice," is a growing drug abuse problem in the United States. The toxic effects of methamphetamine smoking have not been well described. We describe two patients with cardiovascular toxic effects associated with the smoking of crystal methamphetamine. In our first patient, the use of smokeable methamphetamine was associated with the subsequent development of pulmonary edema and a dilated cardiomyopathy. In our second patient, the smoking of crystal methamphetamine likely produced diffuse vasospasm that resulted in acute myocardial infarction, cardiogenic shock, and death. The recognition of potentially lethal cardiac complications associated with the smoking of crystal methamphetamine is of extreme significance and should be emphasized to potential abusers of this drug.