[Prognostic significance of electrocardiographic changes observed in the immediate postoperative period of isolated aortic valve replacements].

The predictive value of early postoperative ECG changes was studied in 144 patients: 106 men (mean age 50.6 +/- 12.9 years) and 38 women (mean age 49.7 +/- 15.3 years), undergoing isolated aortic valve replacement (AVR) with a Björk-Shiley prosthesis between January 1973 and December 1976, using an identical protocol of myocardial protection. Eighty four patients had pure or predominant aortic stenosis, 60 had pure or predominant aortic regurgitation. The early postoperative ECGs (first 30 days) were compared with the preoperative recordings to determine the significance of the changes observed in the immediate postoperative period. Changes of ventricular repolarisation (0.2 mV ST depression and/or 0.5 mV or more T wave inversion) were observed in 44% of cases. Isolated T wave inversion--more common in aortic incompetence than in aortic stenosis--had a good prognosis. On the other hand, ST depression was associated with a worse prognosis (mortality rate three times higher). Conduction defects, either atrioventricular or intra-ventricular, were observed in 30% of cases. They had no effects on mortality or long-term outcome. Atrial fibrillation was observed in 16% of cases and had a good prognosis. In conclusion, the only change in the early postoperative ECG of patients undergoing isolated AVR associated with a poor medium or long-term prognosis, was significant ST depression.