Left atrioventricular valve atresia: clinical management.

Forty cases of left atrioventricular valve (LAV) atresia without aortic stenosis or atresia were reviewed. Thirty-one had mitral atresia and nine had left tricuspid atresia. Eleven had associated pulmonary outflow tract obstruction. Twenty-two (55%) underwent cardiac catheterization and 12 had more than one study. Left atrial pressure was normal in seven infants younger than 2 weeks of age. Twelve patients had an elevated mean left atrial pressure (16-38 mm Hg), including two who had normal left atrial pressures at an earlier study. This suggests that an initially adequate interatrial opening has the potential to become restrictive. Therefore, balloon atrial septostomy is recommended in all patients with LAV atresia who are less than 1 month of age at initial study. Thereafter, serial cardiac catheterizations should be performed to assess changing hemodynamics. Twenty-three patients (56%) had palliative operations to decrease left atrial hypertension (atrial septectomy) and/or optimize pulmonary blood flow (pulmonary artery banding, ductus ligation or systemic-topulmonary anastomosis). Nine survivors (23%) have been followed from 13 months to 23 years (median 7 years). Eight of these had at least one surgical procedure. Prognosis was best in patients with mild-tomoderate pulmonic stenosis and worst in cases with pulmonic atresia. Palliative surgery may improve survival in selected patients with LAV atresia.