Electrocardiographic repolarization abnormalities in subarachnoid hemorrhage.

Electrocardiographic abnormalities, particularly in those waveforms representing ventricular repolarization, have been reported in subarachnoid hemorrhage. This study reports abnormalities on the initial electrocardiogram in 100 patients with SAH. Overall, one or more repolarization abnormalities occurred in 41% of patients. Analysis revealed prolonged QTc interval >460 ms in 16%, ST segment elevation in 9%, ST depression in 3%, T wave inversion in 7%, and U wave >or=100 microV in 15%. Electrocardiographic criteria for left ventricular hypertrophy were met in 14%, and 43% of those patients had no history of hypertension. Serum cardiac troponin I was elevated in 21%, and was significantly associated with QTc interval >460 ms (P <.001). Controlling for gender, those with QTc interval >460 ms were 5.5 times more likely to have elevated serum cardiac troponin I. It is concluded that repolarization abnormalities are present in a high proportion of patients with SAH. Some SAH patients also have left ventricular hypertrophy voltage unrelated to hypertension or coronary artery disease. Prolonged QTc interval after SAH is significantly related to myocardial injury, but unrelated to mortality, and there is no association between ST-T wave abnormalities and either myocardial injury or mortality.