CARDIAC RISK OF NONCARDIAC SURGERY IN PATIENTS WITH ASYMMETRIC SEPTALHYPERTROPHY

Background: Many data are available regarding cardiac risk in patients with coronary artery disease undergoing noncardiac surgery, but few d ata are available regarding risk for patients with hypertrophic cardio myopathy and asymmetric septal hypertrophy. Methods: Seventy-seven pat ients with asymmetric septal hypertrophy were identified in whom an ec hocardiogram had been performed within 24 months of noncardiac surgery . Patients' charts were reviewed for data regarding surgical operation s, including length of surgery, type of anesthesia, and intravascular monitoring used. Data regarding adverse perioperative cardiac events a lso were gathered. Results: Forty percent (n = 31) of patients had one or more adverse perioperative cardiac events, including one patient w ho had a myocardial infarction and ventricular tachycardia that requir ed emergent cardioversion. There were no perioperative deaths. All 31 patients had minor outcomes. Of the 77 patients, perioperative congest ive heart failure developed in 12 (16%). Factors associated with adver se cardiac events were increasing length of surgical time (P < 0.01) m ajor surgery (P < 0.05), and intensity of monitoring (P < 0.05). Age, gender, resting outflow tract gradient, systolic anterior motion of th e anterior mitral leaflet, prior myocardial infarction, severity of mi tral regurgitation, type of anesthetic, septal thickness, and the inte rval between echocardiogram and surgery were not associated with the o ccurrence of adverse cardiac events. Conclusion: Patients with asymmet ric septal hypertrophy undergoing noncardiac surgery have a high incid ence of adverse cardiac events, frequently manifested as congestive he art failure. However, irreversible cardiac morbidity and mortality was extremely low. Important independent risk factors for adverse outcome in all patients include major surgery and increasing duration of surg ery.