To assess the value of exercise testing in the prediction of cardiac risk, 100 patients requiring arterial reconstructive surgery had either treadmill testing or arm ergometry before operation. Thirty-four patients then had abdominal aortic aneurysm repair, 48 had reconstructions for aortoiliac occlusive disease, and 18 had infrainguinal revascularization procedures. Cardiac complications included myocardial infarction in 10%, acute congestive failure in 5%, malignant ventricular arrhythmias in 7%, and cardiac death in 7%. Contingency table analysis showed that patients who achieved less than 85% of their predicted maximum heart rate (PMHR) during exercise testing had a complication rate of 24%, whereas patients who achieved more than 85% of PMHR had a 6% complication rate (p = 0.0396). The degree of ST segment depression during exercise testing was not a significant predictor of cardiac complications. However, patients who had a positive stress test (ST depression more than 1 mm) and achieved less than 85% of their PMHR had a complication rate of 33%, whereas patients with a positive stress test who achieved more than 85% of their PMHR had no complications (p = 0.048). Statistical analysis with a logistic regression model showed two factors to be significant. Patients who achieved a high maximum heart rate during exercise testing had a low probability of developing postoperative cardiac complications (p = 0.04), as did patients who achieved high cardiac work load maximal oxygen uptake (p = 0.03). We conclude that preoperative exercise testing is useful to predict cardiac complications after arterial reconstruction. Patients who are able to achieve more than 85% of their PMHR and a high maximal oxygen uptake represent a low-risk group.

Combined general and epidural anaesthesia and postoperative epidural analgesia do not reduce the incidence of myocardial ischaemia or morbidity compared with general anaesthesia and postoperative intravenous analgesia.

No abstract

The individual and combined predictive values of dipyridamole-thallium imaging and exercise testing were compared in a prospective study of 70 patients who had abdominal aortic aneurysms or aortoiliac occlusive disease that required surgical repair. All patients were evaluated clinically by the same cardiologist and had exercise stress testing and dipyridamole-thallium imaging before admission for surgery. Ten patients were excluded from the study because they had evidence of severe ischemia when tested (ST segment depression greater than 2 mm on exercise testing, severe multivessel disease on thallium imaging). The remaining 60 patients were operated on (abdominal aortic aneurysm repair, 40; aortobifemoral repair, 17; femorofemoral graft, 3). The test results were withheld from the surgeon, anesthetist, and cardiologist before surgery. A total of 22 patients experienced major cardiac complications postoperatively (acute pulmonary edema, 17; acute myocardial, infarction, 5; cardiac death, 2). Thallium imaging showed myocardial ischemia in 31/60 patients. Exercise testing was positive (greater than or equal to 1 mm ST segment depression) in 10/60 patients. Dipyridamole-thallium imaging with a high sensitivity and reasonable specificity is the initial test of choice. Exercise testing is a poor screening test because of its low sensitivity. The combination of the two tests gives the highest positive predictive value and the greatest likelihood ratio. Thus patients assessed initially and found to have positive thallium scan results may be further stratified by exercise testing.

A 61-year-old World War II fighter pilot sustained a gunshot injury to the right fibula and an arteriovenous fistula subsequently developed. Angiographic examination 44 years later for evaluation of an abdominal aortic aneurysm showed an unusually shaped aneurysm and the right arteriovenous fistula with antegrade dilation of the ipsilateral arterial system in continuity with the aneurysm. We hypothesize that this arteriovenous fistula, which involved the peroneal and anterior tibial arteries of the right leg of 44 years' duration, was responsible for the development of this man's abdominal aortic aneurysm.