குழந்தை மருத்துவம் & சிகிச்சை
திறந்த அணுகல்

சுருக்கம்

Balloon Aortic Valvuloplasty

Ngozi C. Agu and P. Syamasundar Rao

Following the description by Lababidi in 1983 of balloon aortic valvuloplasty, it has been adopted by several groups of workers for relief of aortic valve stenosis. The indications for the procedure are peak-to-peak systolic pressure gradients in excess of 50 mmHg with symptoms or ECG changes or a gradient greater than 70 mmHg irrespective of the symptoms or ECG changes. One or more balloon dilatation catheters are placed across the aortic valve percutaneously, over extra-stiff guide wire (s) and the balloon (s) inflated until waist produced by the stenotic valve is abolished. A balloon/annulus ratio is 0.8 to 1.0 is recommended. While trans-femoral arterial route is the most commonly used for balloon aortic valvuloplasty, trans-umbilical arterial or venous or trans-venous routes are preferred in neonate and young infants to avoid femoral arterial injury. Reduction of peak-to-peak systolic pressure gradient along with a fall in left ventricular peak systolic and enddiastolic pressures is seen after balloon aortic valvuloplasty in the majority of patients. Significant aortic insufficiency, though rare, may develop, particularly in the neonate. At intermediate-term follow-up, peak-to-peak gradients, at repeat cardiac catheterization and noninvasive Doppler gradients remain low for the group as a whole. Nevertheless, restenosis, defined as peak-to-peak gradient ≥ 50 mmHg may develop in nearly one quarter of the patients. Predictors of restenosis are age ≤ 3 years and an immediate post-valvuloplasty aortic valve gradient ≥ 30 mmHg. The restenosis may be addressed by repeat balloon valvuloplasty or surgical valvotomy. Feasibility and effectiveness repeat balloon valvuloplasty in relieving restenosis has been demonstrated. Long-term follow-up data suggest, low Doppler peak instantaneous gradients, minimal additional restenosis beyond what was observed at intermediate-term follow-up and progression of aortic insufficiency in nearly one-quarter of patients. Event-free rates are in mid 70s and low 60s respectively at 5 and 10-years after initial balloon valvuloplasty. A number of complications have been reported, but are rare. Comparison with surgical results is fraught with problems, but overall, the balloon therapy appears to carry less morbidity. Immediate, intermediate and long-term follow-up data following balloon aortic valvuloplasty suggest reasonably good results, avoiding/postponing the need for surgical intervention. However, late follow-up data indicate that significant aortic insufficiency with left ventricular dilatation may develope, some require surgical intervention and are of concern. Curr