Death and other events after cardiac repair in discordant atrioventricular connection.

The 1 month, 1 year, and 10 year actuarial survival rates after operation among 99 consecutive patients with discordant atrioventricular connection who underwent intracardiac repair are 86%, 75%, and 68%, respectively. The hazard function of death declines rapidly after operation to reach a low level 6 months postoperatively, and it becomes indistinguishable from that of a matched general population by 4 years. Risk factors for premature death include double-outlet right ventricle, complete heart block preoperatively or developing perioperatively, very young or older (greater than 25 years) age, a high hematocrit value, and earlier date of operation. The last indicates improvement in results in recent years. Eleven (11%) of 99 patients had complete heart block preoperatively, and 23 (26% of 88) developed it perioperatively. Patients with discordant ventriculoarterial connection (i.e., corrected transposition) had a lesser probability of developing heart block after repair than did those with other ventriculoarterial connections. Seventeen (17%) patients required tricuspid (pulmonary venous) valve replacement or repair at the original intracardiac operation, and eight additional patients developed important incompetence after repair. Among the risk factors for incompetence was an Ebstein-like anomaly of the tricuspid valve. Reoperations (three) for conduit obstruction have been no more common than in patients with concordant atrioventricular connection. Fifty-seven (81%) of 70 surviving patients are in New York Heart Association Class I and 12 (17%) in Class II. This, and the single-phase hazard function, indicate that the overall results of cardiac repair in patients with atrioventricular discordant connection could become excellent if the early risks were overcome.