Repolarization and ischemic-like electrocardiographic (ECG) changes observed during acute phase of stroke may cause diagnostic and management dilemmas for the clinician. In this systematic review, we have compiled all information available in the literature on the prevalence of these ECG changes and QT prolongation during the acute phase of stroke and their coexistence with other abnormal cardiac findings. Abnormalities, such as ischemic-like ECG changes and/or QT prolongation, were found in 76% (95% CI 73-90) of patients with subarachnoid hemorrhage, irrespective of whether they had preexisting heart disease or not. Such ECG changes were present in more than 90% of unselected patients with ischemic stroke and intracerebral hemorrhage, but the prevalence was much lower after exclusion of patients with preexisting heart disease. Compared with other abnormal cardiac findings (cardiac wall motion abnormality detected by echocardiography, elevated levels of biochemical markers of myocardial injury, autopsy findings, thallium scintigraphy), these ECG changes were characterized by a high sensitivity but a very low specificity. Thus, in patients with subarachnoid hemorrhage, repolarization and ischemic-like ECG changes are mainly direct consequences of the cerebral condition and their absence essentially rules out cardiac abnormalities. In patients with ischemic stroke and intracerebral hemorrhage, these ECG abnormalities (and QT prolongation) most often represent preexisting coronary artery disease. The specificity of ECG changes to diagnose acute myocardial infarction is low in the acute phase of stroke.
Copyright 2002 S. Karger AG, Basel