Balloon aortic valvotomy through a carotid cutdown in infants with severe aortic stenosis: results of the multi-centric registry.

OBJECTIVES: The purpose of this study was to evaluate the short and intermediate term results of infants who have undergone balloon aortic valvotomy from the carotid arterial approach, and to identify risk factors in those infants who had a poor outcome. METHODS: Between 1988 and 1999, balloon aortic valvotomy was attempted at four centres in 95 infants with severe aortic stenosis. Echocardiographic and hemodynamic data, and outcome, were analysed retrospectively. RESULTS: Valvotomy was accomplished in 92 of the 95 infants, with a median age of 5 days, a range from 0 to 191 days, and weighing 3.4 kg, with a range from 1.0 to 6.5 kg. Major procedural complications occurred in 10 infants. Post-procedural aortic regurgitation was severe in 5 patients. There were 13 early deaths, and 4 late deaths. The period of mean follow-up has been 2.1 years, with a range from 0 to 9.3 years. The actuarial survival at 3 years was 76 +/- 6%. Further interventions were needed in 19 patients, giving a 3-year freedom from reintervention of 67 +/- 6%. The 51 infants who were duct-dependent were further analyzed, and found to have a higher mortality (38%) compared to those infants not dependent on the arterial duct (5%). Risk factors for a poor outcome in the duct-dependent infants were mitral stenosis (p<0.005), a left ventricle which did not form the cardiac apex (p<0.005), and an aortic valve with a diameter of less than 6 mm (p<0.05). CONCLUSIONS: This multi-centric registry shows good results in the intermediate term for treating infants with severe aortic valvar stenosis with balloon valvotomy through a carotid arterial cutdown. Infants dependent on prostaglandin had a worse outcome, especially if they had any of the identified risk factors.

Stent implantation for aortic coarctation and recoarctation.

OBJECTIVE: To determine the early results of balloon expandable stent implantation for aortic coarctation or recoarctation. DESIGN: Prospective observational study. SETTING: Two paediatric cardiology tertiary referral centres. PATIENTS: 17 patients, median age 17 years (range 4.4 to 45) and median weight 61 kg (17 to 92). Six had native aortic coarctation and 11 had aortic recoarctation; 14 had upper limb systolic hypertension. Of those with recoarctation, eight had had at least one previous balloon dilatation attempt and two of these patients also had further surgical interventions. INTERVENTION: Balloon expandable Palmaz iliac stent implantation. MAIN OUTCOME MEASURES: Systolic pressures gradients, minimum aortic diameter, upper limb blood pressures, and incidence of aneurysm formation. RESULTS: 18 stents were implanted during 18 procedures in the 17 patients. Mean peak systolic pressure gradient fell from 26 mm Hg (95% confidence interval (CI), 21 to 31 mm Hg) before to 5 mm Hg (2 to 8 mm Hg) after stent implantation (p < 0.001), and mean minimum aortic diameter increased from 7 mm (95% CI, 6 to 8 mm) before to 11.3 mm (10 to 12.6 mm) after implantation (p < 0.001). Complications occurred in five patients (bleeding in two, stent migration in two, and aneurysm formation in one). Two patients remained borderline hypertensive and eight were receiving antihypertensive treatment at most recent assessment. CONCLUSIONS: Stent implantation for aortic recoarctation and native coarctation gives good immediate results. Careful follow up is necessary to evaluate complications and the long term effect on blood pressure.

Middle aortic syndrome treated by stent implantation.

OBJECTIVES: To determine outcome of stent implantation in patients with middle aortic syndrome. DESIGN: Prospective study, case series. SETTING: A tertiary paediatric cardiology centre in a children's hospital. PATIENTS: Five patients, aged 4 to 17 years (mean 11.4 years), with upper limb hypertension due to middle aortic syndrome. INTERVENTION: Stents were implanted in the mid/lower thoracic/upper abdominal aorta. MAIN OUTCOME MEASURE: Satisfactory deployment of stents and blood pressure control. RESULTS: In all patients, angiocardiography showed long segment stenosis in the mid or lower thoracic/upper abdominal aorta. The pressure gradient was between 40 and 90 mm Hg (mean 63.2 mm Hg). Seven Palmaz stents were implanted. Immediately after implantation, the gradient decreased to between 0 and 35 mm Hg (mean 13.6 mm Hg). Angiography showed a satisfactory result with widely patent stents in all. In one patient, thrombosis of the stent occurred six days after implantation. This was successfully treated with infusion of alteplase, further balloon dilatation, and implantation of a second stent overlapping the first, both dilated to 10 mm diameter. One patient had elective redilatation of the stent six months after implantation, with further reduction of the gradient from 35 mm Hg to 10 mm Hg. At the latest follow up between three and 20 months (mean 12.2 months) after stent implantation, in four patients blood pressure was better controlled with antihypertensive drugs. One patient was normotensive without drugs. Computed tomography showed no aneurysm formation in the region of the stents. CONCLUSIONS: Stent implantation is a preferable alternative to surgery in the treatment of patients with middle aortic syndrome and merits further evaluation.