Experience with the surgical treatment of atrioventricular septal defect with left ventricular outflow tract obstruction
Abstrakt
OBJECTIVES: We sought to determine the prevalence, morphology, surgical methods and results of surgery for left ventricular outflow tract obstruction (LVOTO) associated with atrioventricular septal defect (AVSD). METHODS: Correction of AVSD was performed in 615 patients.
Twenty-three (3.7%) patients with LVOTO were identified. Sixteen (70%) of them had partial and 7 (30%) had complete AVSD.
Surgery for AVSD was performed at a median of 0.6 years (mean 2.1 +/- 3.0 years), and surgery for LVOTO at a median of 3.4 years (mean 4.7 +/- 3.5 years). The point and period prevalence of LVOTO in AVSD were determined.
Detailed morphological study, individualized repair of AVSD with LVOTO and long-term follow-up were performed. Early and long-term results were analysed.
RESULTS: The point prevalence of LVOTO at the time of AVSD repair was 1.3%. The period prevalence of LVOTO was 3.7% in course of 8.3 +/- 6.0 (0-18.4) years and 191.4 patient-years following AVSD repair.
Causes of LVOTO were fibromuscular membrane (n = 17), septal hypertrophy (n = 17), abnormal atrioventricular (AV) valve (n = 9), muscular bands (n = 3), fibrous strands (n = 4) and stenotic aortic valve (n = 2). Usually, a combination of several obstructive lesions was present.
LVOTO was present at the time of AVSD repair in 8 patients (35%) and developed after repair in 15 (65%) patients. Membrane excision (n = 17), myectomy (n = 17), excision of abnormal AV valvar tissue (n = 8), excision of muscular bands and fibrous strands (n = 6), AV valve replacement (n = 2) and aortic valvotomy (n = 2) were required.
There was 1 (4%) early and 1 (4%) late death. Six (29%) survivors required reoperation for recurrence of LVOTO at an average interval of 6.3 +/- 3.2 years after surgery.
The actuarial survival at 1 and 10 years was 96 and 88%, respectively. The actuarial freedom from reoperation for LVOTO was 80, 40 and 20% at 6, 10 and 15 years after surgery, respectively