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 > 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. P ercutaneous balloon valvoplasty was first described in 1983.1 The effectiveness of the method in gradient reduction and the low incidence of restenosis shortly after the procedure were documented in children with congenital aortic stenosis. 2In 1986, the first balloon valvoplasty was performed in a newborn with critical aortic stenosis.3 Good short term results were obtained in a large cohort of children in a multicentre study. 4 Mid-term results, however, showed a substantial incidence of restenosis, severe aortic insufficiency, and reinterventions.5 6 Long term results have so far been published only for children treated after 1 year of age with a 20% restenosis rate and a 21% incidence of significant aortic insufficiency 2-12 years after the procedure.

Congenital Aortic Stenosis in Childhood

“…In a very recent series, including both neonates and older children, 10% of the patients needed reintervention in the long term due to restenosis (Fratz et al, 2008). The survival rate after valvoplasty at 6 and 14.4 years varies between 93% and 100% in older children (Fratz et al, 2008;Galal et al, 1997;Moore et al, 1996;Reich et al, 2004), whereas it varies between 71-74.6% (Fratz et al, 2008;McElhinney et al, 2005) and 71% (Reich et al, 2004) at 10 and 14.4 years respectively when performed in the neonatal period. The freedom from reintervention at mid and longterm follow up varies between 46 and 76% (Fratz et al, 2008;Galal et al, 1997;Moore et al, 1996;Rao, 1999;Reich et al, 2004) after 8-14.4 years in older children, whereas it varies between 47-57.6% (Fratz et al, 2008;McElhinney et al, 2005;Villalba et al, 2002) and 26% (Reich et al, 2004) at 5-10 years and 14.4 years respectively when performed in the neonatal period.…”

“…Both progressive worsening of aortic regurgitation and an increase in residual transvalvar gradient seem to be inevitable. Aortic inssuficiency of at least moderate grade varies between 22.3% and 35% after 5 to 5.3 years Reich et al, 2004) and is about 50% at 7.5 years followup interval (Pedra et al, 2003). The increase in residual transvalvar gradient, or restenosis, varies between 0% and 32.1% according to different definitions of residual gradients used by different investigators (Balmer et al, 2004;Rao et al, 1989;Reich et al, 2004).…”

“…Aortic inssuficiency of at least moderate grade varies between 22.3% and 35% after 5 to 5.3 years Reich et al, 2004) and is about 50% at 7.5 years followup interval (Pedra et al, 2003). The increase in residual transvalvar gradient, or restenosis, varies between 0% and 32.1% according to different definitions of residual gradients used by different investigators (Balmer et al, 2004;Rao et al, 1989;Reich et al, 2004). In a very recent series, including both neonates and older children, 10% of the patients needed reintervention in the long term due to restenosis (Fratz et al, 2008).…”

“…This iatrogenic regurgitation, which was described to be associated with fused bicuspid valves (Reich et al, 2004), has been proven to be related to oversized balloons which lead to improve practice and guidelines, therefore high degrees of immediate post procedural insufficiency became uncommon (McCrindle et al, 1996;Phillips et al, 1987;Sholler et al, 1988). The rate of at least moderate aortic regurgitation shortly after the procedure is between 7.3-22.6% and may progress afterwards (Crespo et al, 2009;Fratz et al, 2008;McCrindle et al, 1996;McElhinney et al, 2005;Reich et al, 2004). Iatrogenic aortic insufficiency, severe hypotension, ventricular arrhythmias, vessel damage, complete atrioventricular block, cardiac tamponade and mitral valve injury are the main serious procedural related complications.…”

Surgical Treatment of Bicuspid Aortic Valve Disease

“…In patients with BAV, the presence of BAV is an important risk factor for progressive dilatation of the aortic root and ascending aorta, even in BAV patients with normal valvular function (Nkomo et al, 2003;Gurvitz et al, 2004;Warren et al, 2006). Thus, because of its situation, patients with hypoplastic annuli and functional bicuspid valves may be primarily considered for surgery in order to prevent the risk of aortic regurgtation and the need for valve replacement (Reich et al, 2004). Actually, any type of treatment for aortic stenosis in newborns and infants is palliative, and future aortic valve replacement is inevitable (Vida et al, 2005).…”