Between 1980 and 1993, 20 patients less than 1 year of age underwent operations for congenital mitral valve disease. Ten patients had congenital mitral incompetence and 10 had congenital mitral stenosis. Mean age was 6.6 +/- 3.4 months and mean weight was 5.6 +/- 1.5 kg. Atrioventricular canal defects, univentricular heart, class III/IV hypoplastic left heart syndrome, discordant atrioventricular and ventriculoarterial connections, and acquired mitral valve disease were excluded. Indications for operation were intractable heart failure or severe pulmonary hypertension, or both. Associated lesions, present in 90% of the patients, had been corrected by a previous operation in seven. In congenital mitral incompetence there was normal leaflet motion (n = 3), leaflet prolapse (n = 2), and restricted leaflet motion (n = 5). In congenital mitral stenosis anatomic abnormalities were parachute mitral valve (n = 4), typical mitral stenosis (n = 3), hammock mitral valve (n = 2), and supramitral ring (n = 1). Mitral valve repair was initially performed in 19 patients and valve replacement in one with hammock valve. Concurrent repair of associated lesions was performed in 12 patients. The operative mortality rate was zero. There were six early reoperations in five patients for mitral valve replacement (n = 4), a second repair (n = 1), and prosthetic valve thrombectomy (n = 1). One late death occurred 9 months after valve replacement. Late reoperations for mitral valve replacement (n = 2), aortic valve replacement (n = 1), mitral valve repair (n = 2), subaortic stenosis resection (n = 1), and second mitral valve replacement (n = 1) were performed in five patients. Actuarial freedom from reoperation is 58.0% +/- 11.3% (70% confidence limits 46.9% to 68.9%) at 7 years. After a mean follow-up of 67.6 +/- 42.8 months, 94% of living patients are in New York Heart Association class I. Doppler echocardiographic studies among the 13 patients with a native mitral valve show mitral incompetence of greater than moderate degree in one patient and no significant residual mitral stenosis. Overall, six patients have mitral prosthetic valves with a mean transprosthetic gradient of 6.2 +/- 3.7 mm Hg. These results show that surgical treatment for congenital mitral valve disease in the first year of life can be performed with low mortality. Valve repair is a realistic goal in about 70% of patients and possibly more with increased experience. Reoperation rate is still high and is related to complexity of mitral lesions and associated anomalies, but late functional results are encouraging.

Reoperation for recurrent aortic arch obstruction can be performed safely, with low rates of mortality and morbidity. This approach should be considered versus balloon angioplasty, especially in patients older than 4 years and in the presence of aortic arch hypoplasia.

From January 1978 to December 1988, 109 phrenic nerve paralyses (PNP) occurred in a total of 9149 cardiac operations performed in a population of patients younger than 15 years old (1.2%) whose age varied from 1 day to 15 years old and mean weight was 11.3 +/- 8.7 kg. PNP was diagnosed in 43 patients after closed procedures (1.2% of 3509 procedures) and in 66 patients after open heart operations (1.2% of 5640 operations). PNP was right sided in 49 cases and left sided in 60 cases. Open heart operations that predisposed to PNP were those which needed harvesting of autologous pericardium (P less than 0.0001) and wide exposure of the great vessels. The modified right Blalock-Taussig shunt was the main cause of PNP in closed procedures (P less than 0.02). Small children tolerated PNP less well. They needed longer ventilatory support (P less than 0.0005) and developed more respiratory complications. Seventeen children underwent plication of the affected hemidiaphragm and could be subsequently extubated. It is concluded that for prevention of PNP, a high level of attention should be exercised in neonates and small children, particularly when pericardium is harvested or when exposure needs extensive dissection of the great vessels and thymus resection, or at reoperation. We also prefer to avoid the use of iced slush lavage. PNP, when symptomatic, is best managed by continuous positive airway pressure (CPAP) ventilation. Diaphragmatic plication is recommended when after 2-3 weeks there is no recovery of diaphragmatic function or when there are troublesome respiratory complications.