Partial atrioventricular canal defect: long-term follow-up after initial repair in patients > or = 40 years old.

OBJECTIVES: This study was undertaken to determine the results of repair of partial atrioventricular (AV) canal in patients > or = 40 years old.

BACKGROUND: Although postoperative outcomes in younger patients have been well documented, the fate of older patients with repaired partial AV canal is less clear.

METHODS: From 1958 to 1990, 31 patients 40 to 71 years old (mean age 51) had repair of partial AV canal. Twenty-three patients had repair of the cleft mitral valve; two had mitral valve replacements; and six needed no mitral valve operation.

RESULTS: Early mortality was 6%. One patient was lost to follow-up. Nine of the early survivors are known to have died. There is a small but significant development over the long term of atrial arrhythmias, complete heart block, subaortic stenosis, recurrent mitral regurgitation and, rarely, mitral stenosis. Three of the 28 patients available for follow-up had mitral valve reoperation and subaortic stenosis developed in 2. Nineteen patients were alive in 1991 (mean follow-up 14 years). Seven patients were in New York Heart Association functional class I, eight were in class II, and four were in class III. Fifteen of the 19 patients reported sustained postoperative improvement.

CONCLUSIONS: Patients > or = 40 years old can have partial AV canal repair with low risk. Long-term survival is good, with subjective improvement in symptoms. Late complications occur but are uncommon, suggesting that long-term follow-up is warranted.