Long term results of percutaneous balloon valvoplasty of congenital aortic stenosis: independent predictors of outcome
Abstract
Objective: To evaluate long term results and independent predictors of outcome of aortic valvoplasty. Design: Retrospective follow up study.
Independent predictors of outcome identified by multiple logistic regression. Setting: Tertiary referral centre.
Patients: 269 consecutive patients treated at the median age of 8 months (0 - 23 years): 80 (30%) under 4 weeks, 59 (22%) between 4 weeks and 1 year, and 130 (48%) over 1 year. The follow up period was up to 14.8 years (median 5.3, in survivors 6.4 years).
Interventions: Percutaneous balloon valvoplasty with mean (SD) balloon to annulus ratio 0.97 (0.08). Main outcome measures: Restenosis greater than or equal to 70 mm Hg, grade 3 aortic insufficiency, cusps disruption, surgery, death, and valvoplasty failure ( significant restenosis or insufficiency or surgery or death).
Results: The mortality rate was 10.4% ( n = 28), the restenosis rate was 16.7% ( n = 45), significant insufficiency developed in 22.3% ( n = 60), surgery was needed in 20.1% ( n = 54), and "valvoplasty failure'' occurred in 41.6% ( n = 112) patients. Mean (SEM) survival probability 14.4 years after the procedure was 0.89 (0.02) and mean (SEM) probability of surgery-free survival was 0.50 (0.08).
The independent predictors were as follows. For restenosis: small aortic annulus; for cusp disruption: large aortic annulus; for insufficiency: bicuspid aortic valve; for need for surgery: bicuspid aortic valve; for death: small aortic annulus, low left ventricular shortening fraction, and low sequential number of the valvoplasty; and for valvoplasty failure: small aortic annulus, bicuspid aortic valve, and high grade of mitral insufficiency.
Conclusion: Independent predictors of unfavourable outcome are small aortic annulus, bicuspid aortic valve, poor function of left ventricle or mitral valve, and limited operator experience.