2 The procedure

2.1 Indications

2.1.1 Balloon valvuloplasty is used to treat aortic valve stenosis (narrowing). This condition may be congenital, or it may develop later in life as a result of rheumatic fever or calcium build-up on the valve that occurs in some people as part of the aging process. The narrowing of the aortic valve causes the pressure in the left ventricle to increase. In order to continue to pump blood through this narrowed area, the left ventricle must pump harder, causing hypertrophy of the left ventricular muscle. Symptoms include angina, shortness of breath or fainting on exertion, and palpitations. Aortic valve stenosis may eventually lead to heart failure.

2.1.2 In infants and children, critical aortic stenosis is very rare and balloon valvuloplasty is usually used palliatively until the child is old enough to have valve replacement.

2.1.3 Standard treatment involves open chest surgery to perform a valvotomy or to replace the valve.

2.2 Outline of the procedure

2.2.1 Balloon valvuloplasty involves inserting a catheter into a large blood vessel, and passing it into the narrowed aortic valve under radiological guidance. A balloon is then inflated to dilate the aortic valve orifice. This can prevent the need for open chest surgery.

2.3 Efficacy

2.3.1 The evidence was limited to non-randomised controlled studies and case series studies. One of the studies that looked at 110 neonates found the mean reduction in systolic gradient to be 65% for the balloon valvuloplasty group, compared with 41% for the open surgery group. A study of adults older than 75 years found the mean gradient decrease to be 24 mmHg for the balloon valvuloplasty group, and 55 mmHg for the open surgery group. In another study, in which 80% (539/674) of patients were considered inappropriate for valve replacement because of age or disease, the mean pressure gradient was reduced by 26 mmHg, but follow-up was only reported for 5 weeks. For more details, refer to the Sources of evidence section.

2.3.2 The Specialist Advisors noted that in adults, surgery was generally the first choice of procedure, but balloon valvuloplasty was useful when surgery was contraindicated.

2.4 Safety

2.4.1 The comparative study of neonates found aortic regurgitation rates of 18% (15/82) in the balloon valvuloplasty group, compared with 3% (1/28) in the open surgery group. In this study, immediate major complications were reported in 4% (3/82) of the balloon valvuloplasty group and 0% (0/28) of the open surgery group. However, the two groups differed in their baseline characteristics. The comparative study of patients older than 75 years showed the death rate in the postoperative and follow-up periods to be 59% (27/46) in the balloon valvuloplasty group and 22% (5/23) in the open surgery group. However, the mean follow-up intervals differed between the groups (22 months for balloon valvuloplasty and 28 months for surgery). For more details, refer to the Sources of evidence section.

2.4.2 The Specialist Advisors considered the main potential adverse effects of the procedure to be myocardial infarction, stroke, aortic valve disruption or regurgitation, myocardial rupture or perforation, mitral valve damage, arterial damage or occlusion, and arrhythmia.

Andrew Dillon
Chief Executive
July 2004