Intra-operative myocardial ischaemia detected by biplane transoesophageal echocardiography during transurethral prostatectomy.
Recent studies have shown an increased late mortality rate due to cardiovascular causes after transurethral compared with open prostatectomy. This has been linked to the demonstration of haemodynamic changes during transurethral prostatectomy, which may cause ischaemic myocardial injury. We used transoesophageal echocardiography (currently the most sensitive modality for detecting myocardial ischaemia) to study 26 patients during prostatectomy under general anaesthesia. Evidence of myocardial ischaemia (as shown by the development of new regional wall motion abnormalities of the left ventricle) occurred in 4 of 22 patients during transurethral and in 3 of 4 patients during retropubic prostatectomy. An intra-operative fall in systolic as well as diastolic blood pressure occurred in 21 of 22 patients during the transurethral procedure and in all 4 patients during retropubic prostatectomy. The duration of anaesthesia and the operation, and the intra-operative blood loss did not differ significantly between patients with and without evidence of intra-operative myocardial ischaemia. However, the maximum intra-operative fall in systolic and diastolic blood pressure, as well as the mass of the prostatic tissue removed, were significantly greater in patients with than in those without evidence of intra-operative myocardial ischaemia, suggesting that the latter may be related to the extent of surgery and the degree of intraoperative hypotension. In this study, 7 of 26 patients (27%) showed evidence of myocardial ischaemia during prostatectomy. However, it remains difficult to explain why intra-operative myocardial ischaemia should result in an increased cardiovascular mortality rate several years after the operation.