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Objective. —Transesophageal echocardiography (TEE) and 12-lead electrocardiography (ECG) are sophisticated techniques that are increasingly being used to monitor for myocardial ischemia during noncardiac surgery. We examined whether the routine use of these techniques has incremental clinical value in identifying patients at high risk for perioperative ischemic outcomes when compared with preoperative clinical data and intraoperative monitoring using continuous two-lead bipolar ECG. Design. —Cohort study. Setting. —Veterans Affairs medical center. Patients. —A total of 332 men undergoing noncardiac surgery who had or were at high risk for coronary artery disease. Interventions. —TEE, 12-lead ECG, and two-lead ECG were performed continuously during noncardiac surgery (47% vascular, 53% nonvascular). Monitoring results were not available to anesthesiologists or surgeons, and data were blindly analyzed after surgery. Main Outcome Measure. —Perioperative ischemic outcomes (cardiac death, nonfatal myocardial infarction, unstable angina). Results. —In a subset of 285 patients who were adequately studied by all three techniques, 111 patients (39%) were identified as having intraoperative myocardial ischemia (by one or more monitoring techniques). By univariate analysis, intraoperative ischemia was associated with all perioperative cardiac outcomes, including ischemic outcomes, congestive heart failure, and ventricular tachycardia ( P ≤.02 for each of the three monitoring techniques). However, when monitoring results for TEE and 12-lead ECG were added to a multivariate model that included preoperative clinical data and continuous two-lead ECG results, the incremental value of TEE was small (odds ratio, 2.6; 95% confidence interval [Cl], 1.2 to 5.7; P =.02) and that of 12-lead ECG was not significant (odds ratio, 1.5; 95% Cl, 0.6 to 3.8). Furthermore, when the multivariate analysis was repeated with only ischemic outcomes, neither TEE nor 12-lead ECG retained significant associations (odds ratio, 2.2; 95% Cl, 0.5 to 9.4, and odds ratio, 1.1; 95% Cl, 0.2 to 6.1, respectively). Conclusion. —When compared with preoperative clinical data and intraoperative monitoring using two-lead ECG, routine monitoring for myocardial ischemia with TEE or 12-lead ECG during noncardiac surgery has little incremental clinical value in identifying patients at high risk for perioperative ischemic outcomes. ( JAMA . 1992;268:210-216)

Objective. —To identify predictors of postoperative myocardial ischemia in patients scheduled to undergo major noncardiac surgery. Design. —Historical, clinical, laboratory, and physiological data were obtained prospectively before and during surgery to identify potential univariate predictors of postoperative myocardial ischemia, which then were entered into multivariate logistic models. Continuous two-lead electrocardiograms before, during, and after surgery were used to identify episodes of myocardial ischemia. Setting. —Department of Veterans Affairs tertiary care hospital. Patients. —A consecutive sample of 474 men at high risk for or with coronary artery disease who were scheduled to undergo major noncardiac surgery (95% compliance rate). Main Outcome Measure. —Significant variables identified by multivariate logistic models that are associated with postoperative myocardial ischemia. Results. —Five major preoperative predictors of postoperative myocardial ischemia were identified: (1) left ventricular hypertrophy by electrocardiogram; (2) history of hypertension; (3) diabetes mellitus; (4) definite coronary artery disease; and (5) use of digoxin. The risk of postoperative myocardial ischemia increased progressively with the number of predictors present: in 22% of patients with no predictors, in 31% with one predictor, in 46% with two predictors, in 70% with three predictors, and in 77% with four predictors. Conclusion. —Patient subgroups who are at high risk for developing postoperative myocardial ischemia and who might benefit the most from intensive Holter monitoring in the postoperative period now can be identified preoperatively. ( JAMA . 1992;268:205-209)

Objective. —To determine the long-term (2-year) cardiac prognosis of high-risk patients undergoing noncardiac surgery and to determine the predictors of long-term adverse cardiac outcome. Design. —Prospective cohort study. Historical, clinical, and laboratory data were collected during the in-hospital period, and at 6 months, 1 year, and 2 years following surgery. Data were analyzed using proportional hazards models. Setting. —University-affiliated Veterans Affairs medical center. Population. —A consecutive sample of 444 patients with or at high risk for coronary artery disease who had undergone elective noncardiac surgery and were discharged from the hospital in stable condition. Main Outcome Measures. —Cardiac death, myocardial infarction, unstable angina, progressive angina requiring coronary artery bypass graft surgery or coronary angioplasty, and new unstable angina requiring hospitalization. Results. —Forty-seven patients (11%) had major cardiovascular complications during a 728-day (median) follow-up period: 24 had cardiac death; 11, nonfatal myocardial infarction; six, progressive angina requiring coronary artery bypass graft surgery or coronary angioplasty; and six, new unstable angina requiring hospitalization. Thirty percent of outcomes occurred within 6 months of surgery and 64% within 1 year. Five independent predictors of long-term outcome were identified. Three predictors reflected the preexisting chronic disease state: (1) the presence of known vascular disease (hazard ratio, 6.1; 95% confidence interval [Cl], 2.5 to 15.0; P P P P P P Conclusions. —The incidence of long-term adverse cardiac outcomes following noncardiac surgery is substantial. At increased risk are patients with chronic cardiovascular disease; at highest risk are patients with acute perioperative ischemic events. We conclude that survivors of in-hospital perioperative ischemic events, specifically myocardial infarction, unstable angina, and postoperative ischemia, warrant more aggressive long-term follow-up and treatment than is currently practiced. ( JAMA . 1992;268:233-239)

Objective. —To determine the incidence, clinical predictors and prognostic importance of perioperative ventricular arrhythmias. Design. —Prospective cohort study (Study of Perioperative Ischemia). Setting. —University-affiliated Department of Veterans Affairs Medical Center, San Francisco, Calif. Subjects. —A consecutive sample of 230 male patients, with known coronary artery disease (46%) or at high risk of coronary artery disease (54%), undergoing major noncardiac surgical procedures. Measurements. —We recorded cardiac rhythm throughout the preoperative (mean=21 hours), intraoperative (mean=6 hours), and postoperative (mean=38 hours) periods using continuous ambulatory electrocardiographic monitoring. Adverse cardiac outcomes were noted by physicians blinded to information about arrhythmias. Main Results. —Frequent or major ventricular arrhythmias (>30 ventricular ectopic beats per hour, ventricular tachycardia) occurred in 44% of our patients: 21% preoperatively, 16% intraoperatively, and 36% postoperatively. Compared with the preoperative baseline, the severity of arrhythmia increased in only 2% of patients intraoperatively but in 10% postoperatively. Preoperative ventricular arrhythmias were more common in smokers (odds ratio [OR], 4.1; 95% confidence interval [Cl], 1.2 to 15.0), those with a history of congestive heart failure (OR, 4.1; 95% Cl, 1.9 to 9.0), and those with electrocardiographic evidence of myocardial ischemia (OR, 2.2; 95% Cl, 1.1 to 4.7). Preoperative arrhythmias were associated with the occurrence of intraoperative and postoperative arrhythmias (OR, 7.3; 95% CI, 3.3 to 16.0, and OR, 6.4; 95% Cl, 2.7 to 15.0, respectively). Nonfatal myocardial infarction or cardiac death occurred in nine men; these outcomes were not significantly more frequent in those with prior perioperative arrhythmias, albeit with wide Cls (OR, 1.6; 95% CI, 0.4 to 6.2). Conclusion. —Almost half of all high-risk patients undergoing noncardiac surgery have frequent ventricular ectopic beats or nonsustained ventricular tachycardia. Our results suggest that these arrhythmias, when they occur without other signs or symptoms of myocardial infarction, may not require aggressive monitoring or treatment during the perioperative period. (JAMA. 1992;268:217-221)