Late Outcomes of Konno-Rastan and Modified Konno for Left Ventricular Outflow Tract Obstruction

BACKGROUND While early outcomes of the Konno-Rastan and modified Konno procedures are known, long-term outcomes remain undetermined. Our objective was to examine long-term clinical and echocardiographic outcomes. METHODS Retrospective review was performed of patients undergoing Konno-Rastan and modified Konno for complex left ventricular outflow tract (LVOT) obstruction from January 1980 to January 2021. The Ross-Konno procedure was excluded due to its often limited ventriculotomy. RESULTS A total of 92 patients were identified: 73 Konno-Rastan and 19 modified Konno. The modified Konno group was significantly younger (median [interquartile range, IQR]: 6, [2-12] years vs 16 [9-32] years, P = .001). LVOT obstruction was multilevel (39 of 92 [42.4%]), tunnel subaortic (35 of 92 [38.0%]), or aortic valve stenosis/annular hypoplasia (18 of 92 [19.6%]). Shone syndrome was present in 20 of 92 (21.7%) patients. Operative mortality was 7 of 92 (7.6%); 4 of 86 (4.7%) in elective vs 3 of 6 (50.0%) in urgent cases ( P = .005). Median follow-up was 12 (IQR, 5-22) years. Aortic valve/LVOT mean gradient was 13 (IQR, 10-18) mm Hg at 1 year but gradually increased to 25 (IQR, 13-46) mm Hg at 10 years. Ejection fraction remained normal. Freedom from reoperation at 5 and 10 years was 77.2% and 58.4% among Konno-Rastan and 57.7% and 41.7% among modified Konno patients ( P = .28), respectively. Overall survival at 5, 10, and 15 years was 82.9%, 76.3%, and 65.5%. Risk factors for mortality included older age, New York Heart Association class III/IV, longer cardiopulmonary bypass time, and multilevel LVOT obstruction. CONCLUSIONS While LVOT obstruction is alleviated early, recurrent LVOT obstruction occurs over time after KonnoRastan and modified Konno procedures. Additionally, despite preserved left ventricular systolic function, late overall survival is poor in this young population. (Ann Thorac Surg 2024;117:973-82) (c) 2024 by The Society of Thoracic Surgeons. Published by Elsevier Inc.