Results of three to 10 year follow up of balloon dilatation of the pulmonary valve

Abstract

Background: The results of immediate and short term follow up of balloon dilatation of the pulmonary valve have been well documented, but there is limited information on long term follow up.

Objective: To evaluate the results of three to 10 year follow up of balloon dilatation of the pulmonary valve in children and adolescents.

Setting: Tertiary care centre/university hospital.

Design: Retrospective study.

Methods and results: 85 patients (aged between 1 day and 20 years, mean (SD) 7.0 (6.4) years) underwent balloon dilatation of the pulmonary valve during an 11 year period ending August 1994. There was a resultant reduction in the peak to peak gradient from 87 (38) to 26 (22) mm Hg. Immediate surgical intervention was not required. Residual gradients of 29 (17) mm Hg were measured by catheterisation (n = 47) and echo Doppler (n = 82) at intermediate term follow up (two years). When individual results were scrutinised, nine of 82 patients had restenosis, defined as a peak gradient of 50 mm Hg or more. Seven of these patients underwent repeat balloon dilatation of the pulmonary valve: peak gradients were reduced from 89 (40) to 38 (20) mm Hg. Clinical evaluation and echo Doppler data of 80 patients showed that residual peak instantaneous Doppler gradients were 17 (15) mm Hg at long term follow up (three to 10 years, median seven), with evidence for late restenosis in one patient (1.3%). Surgical intervention was necessary to relieve fixed infundibular stenosis in three patients and supravalvar pulmonary stenosis in one. Repeat balloon dilatation was performed to relieve restenosis in two patients. Actuarial reintervention free rates at one, two, five, and 10 years were 94%, 89%, 88%, and 84%, respectively. Pulmonary valve regurgitation was noted in 70 of 80 patients at late follow up, but neither right ventricular dilatation nor paradoxical interventricular septal motion developed.

Conclusions: The results of late follow up of balloon dilatation of the pulmonary valve are excellent. Repeat balloon dilatation was performed in 11% of patients and surgical intervention for subvalvlar or supravalvar stenosis in 5%. Most patients had mild residual pulmonary regurgitation but right ventricular volume overload was not required. Balloon dilatation is the treatment of choice in the management of moderate to severe stenosis of the pulmonary valve. Further follow up studies should be undertaken to evaluate the significance of residual pulmonary regurgitation.

Figure 1

Mean (SD) peak to peak systolic pressure gradients measured at cardiac catheterisation before (Pre) and after (Post) balloon dilatation of the pulmonary valve. There is a significant decrease (p < 0.001) immediately following dilatation. The gradient measured during repeat catheterisation in 47 patients at intermediate term follow up (ITFU) is unchanged (p > 0.1) compared with the gradient immediately after dilatation and continues to be lower (p < 0.001) than the gradient before dilatation.

Figure 2

Mean (SD) maximum peak instantaneous Doppler gradients measured before (Pre) and one day after (Post) balloon dilatation of the pulmonary valve and at intermediate(ITFU) and late (LTFU) term follow up. There is a reduction (p < 0.001) after dilatation that remains unchanged (p > 0.1) at ITFU. At LTFU, however, there was further fall (p < 0.01).

Figure 3

Actuarial event free rates after balloon dilatation of the pulmonary valve. Reintervention free rates at one, two, five, and 10 years are 94%, 89%, 88%, and 84%, respectively.

Figure 4

Right ventricular end diastolic dimensions before (Pre) and one day after (Post) balloon dilatation of the pulmonary valve and at intermediate (ITFU) and late (LTFU) term follow up. There was a significant decrease (p < 0.05) in right ventricular size immediately following balloon dilatation. There was no further change at ITFU and LTFU.

Figure 5

(A) Doppler graded (table) pulmonary regurgitation before (Pre) and one day after (Post) balloon dilatation of the pulmonary valve and at intermediate (ITFU) and late (LTFU) term follow up. There is a gradual but significant increase (p < 0.05 to p < 0.001) in the incidence of pulmonary regurgitation. (B) Nature of interventricular septal motion. There is a significant increase (p < 0.05) in the incidence of flat septal motion at LTFU. None of the patients had paradoxical septal motion.