Thirty-year experience with the arterial switch operation

We evaluated the results of the arterial switch operation (ASO) being performed at our institution for more than 30 years and identified risk factors for mortality and reoperation. Clinical outcome of 332 consecutive patients with transposition of the great arteries undergoing ASO was retrospectively analyzed, using surgical reports, medical charts, and latest follow-up echocardiography. Statistical analysis was performed using the Kaplan-Meier method and univariable and multivariable binary logistic and Cox regression analyses. In-hospital mortality was 11.4%. At 15 years, estimated overall survival was 85.2%, and estimated freedom from reoperation was 74.0%. Cross-clamp time (p=0.001) and absence of the Lecompte maneuver (p=0.001) were identified as independent risk factors for in-hospital mortality, whereas coronary problems during surgery (p=0.009) and postoperative pacemaker implantation (p <0.001) were independent risk factors for late mortality. Independent risk factors for reoperation were higher age at the time of the ASO (p=0.002), presence of arch abnormalities (p <0.001), coronary problems during surgery (p=0.005), and duration of ventilation (p <0.001). At latest echocardiography, moderate or severe neoaortic regurgitation was present in 3.4% of the patients. Overall, 30 years of experience with the ASO shows good survival and event-free survival rates. Coronary transfer problems during surgery were found to be an important risk factor for late mortality and reoperation. However, coronary anatomy other than 1LCx-2R and an intramural course of the left coronary artery or left anterior descending artery were not risk factors for mortality or reoperation. Neoaortic regurgitation does not seem to form a major problem