SUPRAVALVAR MITRAL-STENOSIS - RISK-FACTORS FOR RECURRENCE OR DEATH AFTER RESECTION

Objective-To assess the medium term outcome in infants and children af ter surgical resection of supravalvar mitral stenosis with special ref erence to risk factors for mortality or recurrence of supravalvar mitr al stenosis. No detailed follow up has been previously reported in thi s uncommon condition. Design-Prospective cross sectional clinical and echocardiographic follow up. Setting-Paediatric cardiothoracic unit. P atients and methods-23 consecutive children (14 male, nine female, mea n age 3 years 2 months at surgery) who underwent resection of supraval var mitral stenosis between 1978 and 1993. Results-Follow up was for a mean of 58 months (range 0.5-167) after resection of supravalvar mitr al stenosis. Four patients developed recurrent supravalvar mitral sten osis: this has not been reported previously. This was recognised 14-10 8 months after resection and confirmed at repeat operation. Three of t hese patients had successful reoperations but one died. Five other pat ients died. On multivariate analysis the only variable associated with survival free of recurrent supravalvar mitral stenosis was older age (18 months or more) at time of surgery (hazard ratio 0.17, 95% confide nce interval (CI) 0.03 to 0.95, P < 0.05). Five year actuarial surviva l free of recurrent obstruction when supravalvar mitral stenosis was r esected at age less than 18 months was only 39% (95% CI 9 to 69%) comp ared with 73% (95% CI 24 to 93%) in older patients. Conclusion-Suprava lvar mitral stenosis is part of a spectrum of obstructive lesions affe cting the left heart. Recurrent supravalvar mitral stenosis can develo p after surgical resection. The prognosis in those who require resecti on within the first 18 months of life is poor: mortality is high, as i s the risk of recurrent supravalvar mitral stenosis in survivors, prob ably because of continuing turbulent flow across a small left ventricu lar inflow tract.