PREDICTING OF POSTOPERATIVE CARDIAC EVENTS USING AMBULATORY ECG MONITORING PRIOR TO ABDOMINAL AORTIC-SURGERY

Objectives: The purpose of this study was to estimate the value of pre operative electrocardiographic (EGG) monitoring in predicting postoper ative cardiac events in patients undergoing abdominal aortic surgery. Design: A prospective open study. Setting: University Hospital. Materi als: One hundred consecutive patients were studied before aortic or ao rtofemoral surgery by ambulatory ECG monitoring for 24 hours. Chief Ou tcome Measures: An ischaemic episode by ECG criteria was defined as a greater than or equal to 1 mm horizontal or downsloping ST segment dep ression measured 60 msec after the J point and persisting for at least 40 sec. Main Results: Twenty-four patients had preoperative ambulator y ischaemia. Twenty patients had postoperative cardiac events includin g three with fatal myocardial infraction, one with a nonfatal infracti on, eight with unstable angina, three with pulmonary oedema and Jive w ith atrial fibrillation. Sixteen out of 24 (67%) patients with ambulat ory ischaemia had postoperative cardiac events (p < 0.01). Only four e vents occured among 76 patients without ischaemia (p < 0.005). The sen sitivity of ambulatory ischaemia predicting cardiac events was 80% wit h a specificity of 90%, the predictive value of ischaemia was 67% and the predictive value of a negative result was 95%. Conclusions: Preope rative ECG monitoring for myocardial ischaemia could non-invasively id entify patients at high risk for postoperative cardiac morbidity and m ortality after vascular surgery.