Sudden unexpected death after balloon valvuloplasty for congenital aortic stenosis.

OBJECTIVES: The aims of this study were to determine the incidence and risk factors of sudden unexpected death (SUD) after balloon aortic valvuloplasty (BAVP) for congenital aortic stenosis (AS) and to assess the effect of exercise restriction.

BACKGROUND: Exercise restriction is recommended for some patients with congenital AS because of a perceived increased risk for SUD. Little is known about the incidence of SUD in those with treated AS or the efficacy of exercise restriction in preventing SUD.

METHODS: A review was conducted of 528 patients who underwent BAVP for congenital AS at Children's Hospital Boston from 1984 to 2008. Exercise restriction status was ascertained for those ≥4 years of age, censored at aortic valve replacement or transplantation.

RESULTS: Median subsequent follow-up was 12.0 years (range 0 to 24.8 years), for a total of 6,344 patient-years of follow-up. There were 63 deaths, with SUD in 6 patients, 5 of which occurred at ≤18 months of age. For patients ≥4 years of age at most recent follow-up with no histories of pulmonary hypertension (n = 422), median follow-up after BAVP was 14.6 years, for 6,019 patient-years of follow-up. Exercise restriction was prescribed in 183 patients (43%; 2,541 patient-years) and no restriction in 220 (52%; 2,691 patient-years); there were insufficient data in 19 patients. There were 17 deaths in this cohort of 422 patients, with 1 SUD (the patient, who was exercise restricted, died during sleep), for an incidence of 0.18/1,000 patient-years (95% confidence interval: 0.01 of 1,000 to 1.01 of 1,000).

CONCLUSIONS: SUD is extremely rare after BAVP for congenital AS. No beneficial effect of the recommendation for exercise restriction was observed in this longitudinal cohort with 6,000 patient-years of follow-up.