The frequency and significance of ECG changes after transurethral prostate resection

Although many clinicians routinely recommend a base-line preoperative electrocardiogram (ECG) and obtain frequent postoperative ECGs to screen for myocardial infarction or ischemia, the diagnostic utility of screening perioperative ECGs is unknown. The present analysis evaluates the sensitivity and specificity of the perioperative ECG and examines its value as a predictor of early postoperative cardiac events and outcomes during the postoperative year. ECGs obtained preoperatively and on the first 3 postoperative days in 206 men undergoing transurethral prostate resection were analyzed using the Minnesota Code. The occurrence of cardiac events during the operative stay was assessed by measurement of the cardiospecific MB creatine kinase isoenzyme on the first 3 postoperative days and review of the entire clinical course. Twenty-one percent of patients developed postoperative ECG changes, mostly involving the T wave; none had cardiac symptoms or sustained creatine kinase MB elevation. Changes were not significantly more common in men known to have coronary disease. The single patient who had a perioperative myocardial infarction confirmed by enzymes had no codable ECG changes. The specificity of any ECG change for perioperative infarction was 78%; of ST segment changes only, 95%. Only one of the patients (2%) who had postoperative ECG changes had a cardiac event in the year after surgery. Routine perioperative ECGs is of little diagnostic/predictive utility in situations in which the incidence of perioperative myocardial infarction is low.