Long-term results of the Konno procedure for complex left ventricular outflow tract obstruction

Objective: This study was undertaken to determine long-term clinical and echocardiographic outcomes after the Konno procedure. Methods: Fifty-three patients who underwent the Konno procedure between January 1, 1980, and January 1, 2004, were reviewed. Results: Mean age at operation was 19 years (range, 1-65 years). Indications were as follows: complex subaortic or tunnel stenosis in 22 (41%), multilevel left ventricular outflow tract obstruction in 20 (38%), and aortic valve stenosis or hypoplasia in 11 (21%). Before the Konno procedure, 66 operations were performed in 41 (77%) patients. Thirty-three (62%) patients had greater than New York Heart Association class I symptoms preoperatively. A mechanical aortic valve was implanted in 40 (75%), a homograft in 10 (19%), and a xenograft prosthesis in 3 (6%). Mortality at 30 days was 8% (n = 4). Survival at 10 years was 86%. Risk factors for overall mortality were New York Heart Association class (hazard ratio 2.22, P = .04) and longer bypass time (hazard ratio 1.93/hour, P = .04). The cumulative probability of aortic valve reoperation was 19% at 5 years and 39% at 10 years, occurring in 15 patients at a median of 3.8 years. The average left ventricular outflow tract mean gradients were 19 mm Hg at 1 year (n = 9), 13 mm Hg at 1 to 3 years (n = 9), and 13 mm Hg at 3 to 5 years (n = 5). Pulmonary regurgitation was detected in 6 patients. Pulmonary valve replacement was performed in 3 (6%). At the date of last contact, all patients for whom data was available were in New York Heart Association functional class I or II. Conclusion: The Konno procedure is effective, allowing both long-term reduction of left ventricular outflow tract obstruction and improvement in functional class. Prosthetic aortic valve and native pulmonary valve complications may necessitate reoperation.