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 > or = 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.

Figure 1

Regression of aortic annulus diameter (normal z score) and age at valvoplasty. Annulus is 0.751 + 0.0000403 × age in days, R  =  0.620, SEE  =  1.223, p < 0.001.

Figure 2

Comparison of Doppler peak and mean gradients and aortic insufficiency grade (from left to right) before the valvoplasty, a day after, and at the last follow up. Boxes indicate 25th and 75th centiles, error bars 10th and 90th centiles, and circles cases outside this interval. The thin lines within the boxes indicate medians and the thick lines means.

Figure 3

Clinical outcome. A good result was defined as a residual peak Doppler gradient < 70 mm Hg and aortic insufficiency grade < 3. Only the first repeat valvoplasty and/or the first surgery of the aortic valve is shown for each patient. Eight patients had an additional repeat valvoplasty and three patients had another aortic valve surgery. AI, aortic insufficiency; LV, left ventricle; Re-VPL, repeat valvoplasty.

Figure 4

Actuarial probability of survival, surgery-free survival, and reintervention-free survival. Newborns were treated at age ⩽ 28 days and infants at 29 days to 1 year. Error bars indicate standard error of the mean.