Implantation of endovascular stents for the obstructive right ventricular outflow tract.
OBJECTIVE
To evaluate the effectiveness and long term outcomes of catheter intervention for obstructive conduits between the right ventricle and pulmonary arteries.


METHODS
Retrospective chart review.


METHODS
Tertiary care paediatric cardiology unit.


METHODS
70 procedures in 68 children (median age at intervention 6 years, median interval after conduit insertion 3.4 years) were analysed. All children had haemodynamic indications for conduit replacement. Twenty four children underwent a second intervention (stent dilatation in 17, second stent implantation in seven).


RESULTS
Mean (SD) conduit pressure gradient decreased from 44 (18) mm Hg to 18 (12) mm Hg at the initial intervention (n = 62, p < 0.001) and from 39 (15) mm Hg to 23 (10) mm Hg at the second intervention (n = 16, p < 0.001). The percentage of the predicted right ventricular outflow area increased from 17 (9)% to 44 (22)% at the initial intervention (n = 62, p < 0.001) and from 24 (8)% to 29 (11)% at the second intervention (n = 21, p < 0.001). The conduit was subsequently replaced in 33 children. Freedom from conduit replacement from the time of stent implantation was 83%, 75%, and 47% at one, two, and five years, respectively, and from the time of the initial conduit surgery it was 87%, 64%, and 42% at five, eight, and 10 years, respectively. Body growth was maintained, no deaths were reported during follow up, and pulmonary insufficiency was well tolerated.


CONCLUSIONS
A catheter treatment strategy for obstructive conduits is safe and effective in prolonging conduit function.
Sugiyama
H
H
Department of Paediatrics and Surgery, The Hospital for Sick Children, School of Medicine, University of Toronto, Toronto, Ontario, Canada.
Williams
W
W
Benson
L N
LN
D000293:Adolescent; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000379:methods*; D006328:Cardiac Catheterization / Q000379:methods*; D002404:Catheterization / Q000379:methods*; D002648:Child; D017023:Coronary Angiography; D005260:Female; D005500:Follow-Up Studies; D006330:Heart Defects, Congenital; D006439:Hemodynamics; D006801:Humans; D008297:Male; D019233:Retreatment; D012189:Retrospective Studies; D015607:Stents; D016019:Survival Analysis; D014694:Ventricular Outflow Obstruction / Q000503:physiopathology / Q000628:therapy*