Ninety four patients undergoing transurethral resection of the prostate underwent Holter electrocardiographic monitoring pre- and postoperatively. There was no difference in silent myocardial ischaemia incidence or load between the spinal (n = 60) and the general anaesthesia (n = 34) groups. Ischaemic heart disease and a higher Detsky score both significantly increased the incidence of silent myocardial ischaemia but not the ischaemic load of those patients that actually demonstrated ischaemia. In this specific surgical population, not undergoing cardiac or vascular surgery, both ischaemic heart disease and cardiac risk scores are poor predictors of ischaemic load. Merely the presence of short duration silent myocardial ischaemia probably has little predictive value for postoperative adverse outcome.