Function of the anatomic pulmonary valve in the systemic circulation.

The anatomic pulmonary valve, which has thin leaflets with little elastic tissue in the normal heart, must function as the neoaortic valve after arterial switch operation (ASO) for transposition of the great arteries, palliative surgery for hypoplastic left heart syndrome (HLHS), and pulmonary artery-to-aortic (P-A) anastomosis for complex heart disease with subaortic obstruction. The long-term function of this valve under these circumstances is not known. To investigate the function of this valve in the systemic circulation, the follow-up echocardiograms, catheterization data, and angiograms were reviewed for 189 patients at our institution after an ASO (n = 112), palliative surgery for HLHS (n = 45), or P-A anastomosis (n = 32). In addition, the effect on valve function of preoperative anatomy, prior placement of a pulmonary artery band (PAB), and length of follow-up was examined. Neoaortic regurgitation was present in 41% of patients after an ASO (mean +/- SD) follow-up (20 +/- 20; range, 2.2-80.5 months), 60% of patients after an HLHS repair (21 +/- 15; range, 3.7-62.4 months) and 50% after a P-A anastomosis (27 +/- 21; range, 2.6-89.4 months). Only eight patients had more than trivial/mild regurgitation. No neoaortic stenosis was observed. Minor preoperative valve abnormalities did not influence postoperative valve function. Prior PAB placement significantly increased the likelihood of postoperative neoaortic regurgitation after a two-stage ASO but not after a P-A anastomosis. In the ASO group, patients with an intact ventricular septum had a significantly higher prevalence of neoaortic regurgitation than those with a ventricular septal defect.(ABSTRACT TRUNCATED AT 250 WORDS)