Hyperglycemia-induced angina pectoris in a patient with diabetes mellitus.

A patient with diabetes mellitus and coronary artery disease presented with recurring episodes of worsening angina not associated with angiographic changes. Correlation with blood sugars demonstrated that angina would occur during episodes of hyperglycemia. During cardiac catheterization, coronary vascular responses including coronary flow reserve and responses to atrial pacing were measured with a Doppler flow wire before and following a glucose challenge. Coronary microvascular responses were impaired by hyperglycemia.