Percutaneous balloon pulmonary valvuloplasty

Comparative Long-Term results of surgery versus balloon valvuloplasty for pulmonary valve stenosis in infants and children

BACKGROUND

We compared the long-term results of surgical valvotomy (S) versus balloon valvuloplasty (BV) for pulmonary valve stenosis in infants and children.

METHODS

Results after surgical pulmonary valvotomy (with concomitant ASD/VSD closure) (n = 62, age 2.9 +/- 3.5 years) and balloon valvuloplasty (n = 108, age 3.6 +/- 3.9 years) were analyzed. Transvalvular mean pressure gradient decrease, freedom from reintervention for restenosis, pulmonary valve insufficiency, and tricuspid valve insufficiency were considered.

RESULTS

Mean pressure gradient decreased significantly more in the surgical group (from 64.8 +/- 30.8 mm Hg to 12.8 +/- 9.8 mm Hg at a mean follow-up of 9.8 years) than after BV (decreasing from 66.2 +/- 21.4 mm Hg to 21.5 +/- 15.9 mm Hg after a mean of 5.4 years; p < 0.001). Moderate pulmonary valve insufficiency occurred in 44% after surgery, and in 11% after BV (p < 0.001). Tricuspid valve insufficiency occurred in 2% after surgery, and in 5% after BV. Restenosis occurred in 3 surgical patients (5.6%), 2 patients required reoperation, and 1 patient required a balloon valvotomy. Restenosis developed in 13 BV patients (14.1%): 6 patients were redilated and 7 patients required surgery. Surgical valvotomy led to significantly less reinterventions than balloon valvuloplasty (p < 0.04).

CONCLUSIONS

Surgical relief of pulmonary valve stenosis produces lower long-term gradients and results in longer freedom from reintervention. Balloon valvuloplasty may remain, despite these results, the preferred therapy for isolated pulmonary valve stenosis, because it is less invasive, less expensive, and requires a shorter hospital stay. Surgery should remain the exclusive form of therapy in the presence of concomitant intracardiac defects, which need to be addressed.

Balloon dilatation for critical pulmonary stenosis

This study was conducted to investigate the outcome of balloon valvuloplasty for critical pulmonary stenosis in young infants. During a 6.2-year period between January 1992 and February 1998, 34 infants with critical pulmonary stenosis, aged 1 to 58 days (16.8+/-16.6 days), underwent attempted balloon valvuloplasty in this institution. The procedure was accomplished in 28 patients, but failed in six. Surgical pulmonary valvotomy was performed in the six patients with one mortality. Immediately following valvuloplasty, the mean right ventricular systolic pressure decreased from 109.2+/-28.6 to 55.1+/-23.6 mm Hg in the 28 patients (P<0.01). The mean pressure gradient decreased from 85.6+/-29.4 to 26+/-21.4 mm Hg (P<0.01). However, one who had a severely hypoplastic right ventricle requiring prolonged prostaglandin E1 infusion after valvuloplasty underwent a right ventricular outflow tract patch. After a follow-up period ranging from 2 months to 6.4 years (30.5+/-19.1 months), one patient developed recurrent pulmonary stenosis and underwent a repeated balloon valvuloplasty. Of the 27 patients (79%) with a definitive success of balloon valvuloplasty, the mean pressure gradient estimated with Doppler echocardiography at most recent follow-up was 15.2+/-6.8 mm Hg. Therefore, balloon valvuloplasty is the procedure-of-choice for critical pulmonary stenosis. Surgery should be reserved for those with unsuccessful balloon valvuloplasty.

Late results of balloon pulmonary valvuloplasty in adults

This study shows late results of adult patients with pulmonary stenosis after successful balloon pulmonary valvuloplasty. Late results of this procedure are as good as early results.

Treatment of critical pulmonary valve stenosis by balloon dilatation in the neonate

Critical pulmonary valve stenosis represents an emergency, and immediate treatment is mandatory. The purpose of this study was to evaluate the immediate and medium-term results of pulmonary valve dilatation. We report 18 neonates in whom pulmonary valvuloplasty was attempted. The procedure could be accomplished in 14 patients. The angiographically determined diameters of the pulmonary and tricuspid valve at the time of procedure were 5.6 +/- 1.5 mm and 14.0 +/- 5.4 mm. The mean Doppler gradient decreased from 71 +/- 27 mm Hg to 27 +/- 14 mm Hg. Perforation of the right ventricular outflow tract was the major complication in three patients with one fatal event. Infusion of prostaglandin E1 could be discontinued 1 to 5 days after the procedure. On follow-up three children required a second balloon dilatation with good results. Seven patients monitored for more than 9 months with a mean follow-up time of 34.4 +/- 16 months had a residual gradient of 11.6 +/- 6.7 mm Hg. In spite of a hypoplastic pulmonary valve annulus in seven of the patients, results were good and surgery could be avoided.

Morphologic and hemodynamic consequences after percutaneous balloon valvotomy for neonatal pulmonary stenosis: medium-term follow-up

OBJECTIVES

This study sought to evaluate ventricular and valvular morphologic changes, hemodynamic consequences and clinical outcomes of pulmonary balloon valvotomy performed in the neonatal period.

BACKGROUND

Previous studies support percutaneous balloon valvotomy as the management option of choice for infants and children with valvular pulmonary stenosis. Less information is available to define the impact of valvotomy on the clinical course when performed in the neonatal period.

METHODS

Patient records, catheterization data, cineangiograms and selected echocardiograms (initial and most recent studies) of 37 consecutive neonates undergoing attempted balloon dilation were reviewed.

RESULTS

Dilation was accomplished in 35 (94%) of 37 attempts. Immediately after dilation, the transvalvular peak to peak systolic gradient decreased from 60 +/- 22 mm Hg (mean +/- SD, range 20 to 100) to 11 +/- 10 mm Hg (range 0 to 45) (p < 0.0001), and the right ventricular/aortic systolic pressure ratio decreased from 1.25 +/- 0.43 (range 0.5 to 2.6) to 0.66 +/- 0.22 (range 0.2 to 1) (p < 0.0001). Oxygen saturation measured by percutaneous oximetry increased from 80 +/- 7% to 92 +/- 4% (p < 0.0001). Three patients died (8%), and two required repeat balloon dilation. At the follow-up visit (median 31 months, range 6 months to 8 years), the estimated peak instantaneous Doppler gradient was 15 +/- 9 mm Hg (range 6 to 36). Thickening of valve leaflets, initially present in 93% of patients, was found in only 4%, and leaflet mobility improved in all. Hypoplasia of the right ventricle, initially present in 31%, was found in only 4% at the latest evaluation. Pulmonary annulus diameter Z score increased from -3 +/- 1.0 to 0 +/- 0.1 (p < 0.0001). Freedom from reintervention was 90%, 84% and 84% at 1, 2 and 8 years, respectively.

CONCLUSIONS

These data support the application of balloon valvotomy as the initial intervention in the treatment algorithm for neonates with critical pulmonary valve stenosis. Medium-term follow-up observations demonstrate sustained hemodynamic relief and support maturation of the right ventricle and pulmonary valve annulus, with the expectation of a good long-term outcome.

Percutaneous balloon valvuloplasty in severe pulmonary valvular stenosis

Percutaneous balloon pulmonary valvuloplasty (PBPV) was achieved successfully in 20 of 22 patients with severe pulmonary valvular stenosis, aged two days to ten years (median four years and two months). The diameters of the balloon for PBPV were 88-125% (mean +/- SD = 109.5 +/- 10.0%) of the pulmonary valve annulus. PBPV failed in 2 patients because of the inability of the cardiac catheters to cross the stenotic valve. A significant reduction of right ventricle-pulmonary artery (RV-PA) pressure gradient occurred in all 20 patients (mean +/- SD = 72.1 +/- 10.3%). The mean RV-PA pressure gradient was reduced from 93.2 +/- 33.1 to 26.3 +/- 15.6 mmHg (P < 0.0001) and the mean right ventricular peak systolic pressure fell from 117.2 +/- 32.4 to 51.6 +/- 17.3 mmHg (P < 0.0001). Five (25%) of 20 patients had an infundibular gradient before PBPV. Two (10%) developed a new infundibular stenosis immediately after PBPV. Four (20%) presented with cyanosis, which disappeared after the successful PBPV. Two patients (10%) who showed a residual RV-PA pressure gradient of more than 40 mmHg had a significant infundibular obstruction initially. Two patients underwent recatheterization fifteen months after PBPV owing to a significant residual RV-PA pressure gradient and had no reductions in right ventricular pressure and RV-PA pressure gradient, but resolution of infundibular obstruction was noted in both. Repeat PBPV was successfully performed on these 2 patients. No significant complications were noted in any patient.(ABSTRACT TRUNCATED AT 250 WORDS)

Pulmonary valvuloplasty using Inoue balloon catheter

We report balloon pulmonary valvuloplasty using the Inoue catheter in three patients with severe valvular pulmonic stenosis. The mean right ventricular systolic pressure and the pulmonary valvular peak to peak systolic gradients decreased from 140 +/- 23 to 40 +/- 26 mmHg (P < 0.001) and 120 +/- 26 to 8 +/- 8 mmHg (P < 0.001) respectively. This report suggests that pulmonary valvuloplasty using the Inoue balloon catheter technique is feasible, safe and effective.

Independent predictors of long-term results after balloon pulmonary valvuloplasty. Valvuloplasty and Angioplasty of Congenital Anomalies (VACA) Registry Investigators

BACKGROUND

This study was performed to determine independent predictors of long-term outcome after percutaneous balloon dilation of congenital pulmonary valve stenosis. Smaller follow-up series of patients after balloon pulmonary valvuloplasty have shown inconsistent results regarding the independent relation between prognostic factors and long-term outcome, as many patient selection and technical factors are correlated.

METHODS AND RESULTS

Follow-up data were obtained for 533 patients from 22 institutions at up to 8.7 years after an initial balloon pulmonary valvuloplasty. Patients were grouped based on defined long-term outcomes, and the independent effects of patient selection and technical factors were sought in multivariate statistical analyses. At follow-up, 23% of patients were noted to have an outcome judged to be suboptimal because of either a residual right ventricle to pulmonary artery peak systolic gradient of > or = 36 mm Hg or further treatment of pulmonary stenosis requiring repeat balloon pulmonary valvuloplasty or surgical therapy. Significant independent predictors of a suboptimal long-term outcome included an earlier study year of the initial valvuloplasty (adjusted odds ratio, 0.71 per consecutive year), a small valve hinge point diameter (0.81 per 1-mm increase), and a higher immediate residual gradient (1.32 per 10 mm Hg increase). A smaller ratio of balloon to valve hinge point diameter significantly predicted suboptimal outcomes for patients with valve morphologies classified as typical (0.52 per 0.1 increase in ratio) and complex (primarily postsurgical valvotomy, 0.43) but not for patients with dysplastic (0.95) or combined morphologies (dysplasia with commissural fusion, 1.01). Patient age, the presence of Noonan's syndrome or associated cardiac lesions, pre-balloon valvuloplasty hemodynamic parameters, and the use of a simultaneous double-balloon technique did not independently predict follow-up outcomes.

CONCLUSIONS

Accurate prognostication after balloon pulmonary valvuloplasty depends on the careful determination of valvar anatomy. The use of an appropriate ratio of balloon to valve hinge point diameter in the setting of typical valve morphology will optimize the chance of long-term success.

Long-term results after balloon pulmonary valvuloplasty in adults

Percutaneous balloon pulmonary valvuloplasty for congenital pulmonary valve stenosis was performed in 40 adult patients (aged 18 to 56 years). The duration of follow-up was 24.5 +/- 11.5 months. The peak systolic pressure gradient from the right ventricle to the pulmonary artery decreased from 107 +/- 29 mm Hg to 37 +/- 25 mm Hg immediately after the procedure. On follow-up, gradient obtained either by cardiac catheterization or Doppler echocardiography was 31 +/- 13 mm Hg. In eight patients with residual gradient after valvuloplasty of > 50 mm, the mean peak systolic gradient decreased from 74.5 +/- 18.3 to 33.5 +/- 13.9 mm Hg on follow-up. Thus balloon pulmonary valvuloplasty is a safe and effective procedure for the treatment of adult patients with pulmonic stenosis; there is a tendency for high residual gradients to regress on follow-up.

Balloon pulmonary valvoplasty: factors determining short- and long-term results

Balloon pulmonary valvoplasty was performed in 139 patients (age 2-44 years) with pulmonary valve stenosis. The right ventricular peak systolic pressure decreased from 137.1 +/- 46.8 mmHg to 76 +/- 51.3 mmHg (P < 0.001) and the right ventricle to pulmonary artery peak systolic gradient decreased from 116.3 +/- 49 mmHg to 54.4 +/- 51.9 mmHg (p < 0.001). There was no significant change in systemic artery systolic pressure. The right ventricular peak systolic pressure to systemic artery systolic pressure ratio decreased from 1.13 +/- 0.41 to 0.63 +/- 0.42 (P < 0.001). Patients with incomplete immediate relief of obstruction (right ventricle to pulmonary artery peak systolic gradient > 35 mmHg) had higher pre-dilatation right ventricular peak systolic pressure (161.1 +/- 45.3 mmHg vs. 93.9 +/- 38.8 mmHg, P < 0.001) and higher right ventricular peak systolic pressure to systemic artery systolic pressure ratio (1.31 +/- 0.42 vs 0.98 +/- 0.33, P < 0.001) pre-dilatation and were older (17.2 +/- 8.6 years vs. 12.8 +/- 9.7 years, P < 0.01). The residual right ventricle to pulmonary artery peak systolic gradients in the majority of patients were infundibular, which regressed at follow up even in patients who did not receive long-term oral beta blockers. Follow up catheterisation in 79 patients after 13 +/- 8.7 months showed a further fall in right ventricular peak systolic-pressure (P < 0.001) and right ventricle-to-pulmonary artery peak systolic gradient (P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Pulmonary valvuloplasty in adults using the Inoue balloon catheter

This report describes a new balloon pulmonary valvuloplasty technique using the Inoue balloon catheter performed in 14 consecutive adult patients, aged 17-47 years (mean 27). The mean right ventricular systolic pressure and the pulmonary valvular peak-to-peak systolic gradient decreased from 102 +/- 41 to 52 +/- 19 mm Hg (p = 0.001) and 81 +/- 40 to 7 +/- 7 mm Hg (p = 0.0002), respectively. An infundibular peak-to-peak systolic gradient either developed (n = 13) or increased (n = 1). None of the patients were treated with beta-adrenergic blockers before or after the valvuloplasty. Eight patients underwent repeat hemodynamic study 12-30 months (mean 17) after treatment, and had no evidence of valvular restenosis. The mean right ventricular systolic pressure and the mean infundibular peak-to-peak systolic gradient decreased, compared to the values immediately after valvuloplasty (54 to 40 mm Hg, p = 0.03, and 28 to 10 mm Hg, p = 0.03, respectively). The study suggests that pulmonary valvuloplasty in adults using the Inoue balloon catheter technique is feasible, safe, and effective.

Transcatheter treatment of pulmonary outflow tract obstruction: a review

The role of transcatheter methods in the management of pulmonary outflow tract obstruction are discussed in this review. Balloon pulmonary valvuloplasty for relief of isolated pulmonary valve stenosis has been successfully used by many investigators and is the procedure of choice for the management of these lesions. Supravalvar pulmonic stenosis, if discrete, can be relieved by balloon dilatation. Cyanotic children with interatrial right-to-left shunts secondary to severe valvar pulmonary stenosis respond in a manner similar to that observed with isolated pulmonary valve stenosis. In these patients, balloon valvuloplasty is the treatment of choice and may be corrective in most patients. In patients with interventricular right-to-left shunting secondary to pulmonary outflow tract obstruction and in patients with narrowed BT shunts, balloon dilatation may be an effective palliative procedure in a substantial proportion of patients obviating the need for an initial or second palliative shunt. Balloon dilatation is recommended if the patient's size or cardiac anatomy make them unsuitable for safe total surgical correction. In patients with pulmonary atresia, either initial opening of the atretic pulmonary valve by laser or by surgery with subsequent balloon dilatation are potentially beneficial in reducing the total number of surgical procedures that these children are likely to require. However, further clinical trials are needed before their general use.

Hemodynamic findings during exercise on a bicycle ergometer following balloon valvuloplasty of pulmonary stenosis in children and adolescents

Eleven patients (4 female, 7 male), age range 3.3 to 24.8 years (mean 11.10 years) treated for isolated pulmonary stenosis underwent cardiac catheterization and percutaneous transluminal balloon valvuloplasty (PTVP). The right ventricular systolic pressure (RVSP) before valvuloplasty ranged from 31 to 127 mmHg (mean 79 mmHg) decreasing to 28 to 62 mmHg (mean 42 mmHg) immediately after the dilatation. The peak systolic gradient of the pulmonary valve (delta p RV-PA) before valvuloplasty ranged from 22 to 107 mmHg (mean 61 mmHg) and decreased to a range of 14 and 45 mmHg (mean 23 mmHg) immediately after the dilatation. Balloon valvuloplasty was performed using balloons of 13 to 31 mm in diameter. On 11 patients cardiac catheterization and Doppler echocardiography were repeated between 11 months and 5.3 years (mean 3.11 years) after the balloon valvuloplasty showed a further significant fall in the gradient of pressure. The right ventricular systolic pressure ranged from 20 to 51 mmHg (mean 31.7 mmHg) while the transpulmonary gradient varied from 3 to 24 mmHg (mean 11.6 mmHg). At the time of follow-up examination the patients were aged between 7.2 and 25.7 years (mean 15.9 years). On average the second catheterization was performed 3.11 years following the first hemodynamic study. The follow-up examination encompassed clinical examination, electrocardiogram, Doppler echocardiography, and right heart cardiac catheterization. During right heart cardiac catheterization the children exercised on a bicycle ergometer for three min at 50 or 100 W depending on their body surface area. During this exertion, pressures of the right ventricle and the pulmonary artery as well as heart rate and oxygen saturation were recorded.(ABSTRACT TRUNCATED AT 250 WORDS)

Balloon pulmonary valvuloplasty in infants: a quantitative analysis of pulmonary valve-anulus-trunk structure

OBJECTIVES

The present study was designed to establish possible predictors of unfavorable outcome in infants with pulmonary valve stenosis.

BACKGROUND

Balloon pulmonary valvuloplasty is the treatment of choice for typical pulmonary valve stenosis. Patients with dysplastic valves may be less suitable candidates for this procedure because they have morphologic abnormalities of the complex valve-anulus-trunk that cause the obstructive phenomenon.

METHODS

Twenty-five children (mean age +/- SD 1.1 +/- 0.7 years) with normal anulus diameter underwent balloon pulmonary valvuloplasty using a balloon/anulus ratio of 1.2 +/- 0.11. From the lateral view of a right ventricular angiogram, the following variables were quantified and scored: A, supravalvular narrowing; B, texture of the valve surface; C, diastolic deformity of the Valsalva sinuses; D, trunk/anulus ratio; E, systolic valve motion; and F, presence of a contrast jet. Paired t test, stepwise multivariate correlation with "dummy" variable methods were applied for both hemodynamic and valve-anulus-trunk determinations.

RESULTS

The right ventricular-pulmonary artery gradient decreased from 66 +/- 21 (range 40 to 120) to 24 +/- 11 (range 10 to 50) mm Hg (p less than 0.001), whereas the right ventricular systolic pressure decreased from 89 +/- 20 (range 60 to 130) to 48 +/- 15 (range 30 to 80) mm Hg (p less than 0.001). Only variables A, B and D had significant influence in a percent reduction in right ventricular pulmonary artery gradient (R2 0.94, SEE 5.7; p less than 0.001). A score greater than or equal to greater than 4 obtained by adding the values from these three variables was correlated with poor outcome.

CONCLUSIONS

These data show that there is an adequate relation between scores and outcome. We conclude that children less than 2 years old with pulmonary valve stenosis and a score greater than or equal to 4 should not be candidates for balloon pulmonary valvuloplasty.

Intermediate-term outcome after pulmonary balloon valvuloplasty: comparison with a matched surgical control group

To assess late (4 to 5 years) gradient reduction after pulmonary balloon valvuloplasty in childhood, and to compare the effectiveness of valvuloplasty with that of surgical valvotomy, 20 valvuloplasty-treated children and their age- and gradient-matched surgical control patients underwent prospective, noninvasive evaluation. The average age at intervention was 4.3 +/- 1 years for the valvuloplasty group versus 4.7 +/- 0.8 years for the surgical control group (p = NS). Before intervention the peak systolic pulmonary stenosis gradient was 76 +/- 5 and 74 +/- 4.4 mm Hg for the valvuloplasty and surgery groups, respectively (p = NS). Late evaluation consisted of clinical examination, two-dimensional echocardiogram and Doppler study, 24-hour Holter monitoring, 12-lead electrocardiogram, exercise treadmill study and chest radiograph performed an average of 5.3 +/- 0.3 years after valvuloplasty and 11.7 +/- 0.5 years after surgery (p less than 0.01). The patients treated with balloon valvuloplasty had no evidence of restenosis; the residual pulmonary stenosis gradient at follow-up was 24 +/- 2.7 mm Hg (range 8 to 48) versus 35 +/- 3.6 mm Hg (range 19 to 70) immediately after valvuloplasty (p = NS). Comparison of the late residual gradients between treatment groups showed no hemodynamically significant difference (24 +/- 2.7 versus 16 +/- 1.5 mm Hg, balloon versus surgery; p less than 0.01). However, there was, a significant difference in the degree and severity of pulmonary valve insufficiency and ventricular ectopic activity between groups. In the balloon valvuloplasty group 11 patients had no pulmonary insufficiency, and the remaining 9 had mild insufficiency.(ABSTRACT TRUNCATED AT 250 WORDS)

Transesophageal echocardiographic monitoring of interventional cardiac catheterization in children

Transesophageal echocardiography was used prospectively in 22 children scheduled for interventional cardiac catheterization (9 with pulmonary valvuloplasty, 5 with aortic valvuloplasty, 1 with pulmonary angioplasty, 2 with aortic angioplasty, 2 with patent ductus arteriosus occlusion and 3 with Mustard baffle dilation) to determine its potential value as a monitoring technique. The patients ranged in age from 0.9 to 14.6 years (mean 5.4) and in weight from 9.5 to 49.2 kg (mean 21.1). Studies were completed in all patients without complications. Preintervention studies provided important new information in two patients, leading to cancellation of the planned procedure. Major contributions of transesophageal monitoring included 1) a real time assessment of catheter placement across either atrioventricular valve and the aortic valve during balloon valvuloplasty; 2) immediate assessment of aortic valve and aortic wall morphology during balloon dilation; and 3) detailed morphologic and hemodynamic information together with enhanced catheter guidance during Mustard baffle dilation. After pulmonary valvuloplasty, partial chordal rupture of the tricuspid valve was documented in one patient. In two patients, balloon catheter position was modified according to the transesophageal findings. The assessment of changes in pulmonary valve morphology and transcatheter occlusion of a patent ductus arteriosus was not enhanced by single-plane transesophageal monitoring. Pulsed wave Doppler studies contributed additional information in the assessment of immediate hemodynamic changes after interventional procedures. Transesophageal echocardiography is a new important guiding and monitoring technique during interventional cardiac catheterization procedures in children. It can provide additional real time imaging information, immediate identification of complications and assessment of hemodynamic changes.

Transcatheter double-blade valvotomy for the treatment of valvar pulmonary stenosis

A transcatheter double-blade valvotome for cutting a stenotic pulmonary valve has been devised. The valvotome consists of a retractable rhomboid structure at its tip, with a blade on each side of its proximal half. By tugging the extended blades from the pulmonary artery to the right ventricle it is possible to tear the stenotic valve. After animal experiments proved the feasibility and safety of this method, it was used in three children with pulmonary stenosis. The results were encouraging.

Long-term results after balloon pulmonary valvuloplasty

BACKGROUND

The objective of this study was to determine the long-term outcome of patients after percutaneous balloon pulmonary valvuloplasty (BPV) treatment of congenital pulmonary valve stenosis.

METHODS AND RESULTS

This study represents a case series with duration (mean +/- SD) of follow-up of 4.6 +/- 1.9 years. Forty-six patients with a median age of 4.6 years (range, 3 months to 56 years) had BPV at one academic institution between June 1981 and December 1986. Mean peak systolic pressure gradients from the right ventricle to the pulmonary artery were as follows: before BPV, 70 +/- 36 mm Hg; immediately after BPV, 23 +/- 14 mm Hg; at intermediate follow-up by cardiac catheterization or Doppler echocardiography at less than 2 years after BPV, 23 +/- 16 mm Hg (n = 33); and at long-term follow-up by Doppler at more than 2 years after BPV, 20 +/- 13 mm Hg (n = 42). BPV acutely reduced the gradient to less than 36 mm Hg for 41 of 46 (89%) patients. Available gradients at long-term follow-up were less than 36 mm Hg for 36 of 42 (86%) patients without additional procedures. A patient age of less than 2 years at the initial BPV was a significant risk factor for gradients over 36 mm Hg at follow-up.

CONCLUSIONS

BPV provides long-term relief of pulmonary valvular obstruction in the majority of patients. Close follow-up of patients who require BPV at less than 2 years of age is warranted.

Early complications of interventional balloon catheterisation in infants and children

Interventional balloon catheterisation is now the recommended procedure for several congenital heart defects. The overall complication rate in the first 160 children (median age 3 years) to undergo balloon intervention (excluding balloon atrial septostomy) at the Brompton Hospital was 24% (14% excluding haemorrhage and including three deaths (1.9%]. Most complications were related to vascular problems at the site of cardiac catheterisation. Complications were more common in the younger patient, especially neonates, and also in procedures that were ultimately unsuccessful. Most complications were transient and usually had no long term effects. Improvements in equipment design and technical expertise may reduce morbidity from these procedures.

Operative findings after percutaneous pulmonary balloon dilatation of the right ventricular outflow tract in tetralogy of Fallot

Since 1983 percutaneous balloon dilatation of the right ventricular outflow tract has been performed as an alternative to surgical palliation in selected cases of tetralogy of Fallot at the Royal Liverpool Children's Hospital. From 31 December 1984 to 31 December 1988, 27 of these patients underwent subsequent surgical correction. Age at operation ranged from 7 to 58 months (median 2.7 years). The mean interval between balloon dilatation and correction was 15.6 months (range 3-39 months). Two patients had a systemic pulmonary shunt operation performed before dilatation and a further five required one afterwards. Overall 20 (74%) patients had some anatomical alteration as the result of balloon dilatation, while in seven (26%) there was no discernible change in the right ventricular outflow tract. There was no consistent relation between the ratio of balloon size to pulmonary annulus diameter and the morphological findings. Balloon dilatation may obviate the need for systemic-pulmonary shunt at the expense of some structural damage, particularly to the posterior cusp. The present data suggest that dilatation does not bring about growth of the annulus to such an extent that transannular patch is no longer needed at intracardiac repair.

Balloon aortic valvuloplasty in children

The technique of balloon aortic valvuloplasty has been used in infants, children, and adults since its first description in 1983. Immediate results reported by several workers and intermediate-term results by a few workers appear encouraging. Complications are minimal although potential for arterial complications and aortic insufficiency should be recognized. Significant restenosis rates at intermediate-term follow-up have been reported and could be minimized by reducing the risk factors associated with recurrence. Echo-Doppler studies are useful in follow-up evaluation of balloon valvuloplasty. The results seem to compare favorably with those following surgical valvotomy. The indications are essentially the same as those used for surgery; a gradient in excess of 80 mmHg irrespective of symptoms or a gradient greater than or equal to 50 mmHg with symptoms or ST-T wave changes. Previous surgical valvotomy is not a contraindication for balloon valvuloplasty. The technique is applicable to subaortic membranous stenosis as well. Thus far only one- to two-year follow-up results are available. Five- to ten-year follow-up results to document long-term effectiveness of balloon aortic valvuloplasty are needed. Miniaturization of currently bulky dilating catheter systems and improving rapidity of inflation/deflation of balloons are necessary to increase safety and effectiveness of these techniques in infants and children. Meticulous attention to the details of the technique and further refinement of the procedure may further increase effectiveness and reduce the complication rate.

Balloon dilatation of critical stenosis of the pulmonary valve in neonates

Percutaneous balloon dilatation was attempted in 15 consecutive neonates (mean age 7.3 (range 1-27) days and weight 3.2 (range 2.5-4.1) kg) with critical stenosis of the pulmonary valve. Dilatation was successful in 11 (73%) patients. The mean balloon to annulus ratio was 1.1 (range 0.6-1.77). The ratio of right ventricle to femoral artery systolic pressure decreased from a mean (1 SD) of 1.4 (0.32) before to 0.8 (0.24) after dilatation and the transvalvar gradient decreased from 81 (29.7) mm Hg before to 33 (27.7) mm Hg after dilatation. All four (27%) patients in whom dilatation was unsuccessful underwent surgical valvotomy. Complications of balloon dilatation occurred in three (20%) patients; these included retroperitoneal haematoma (one) and iliofemoral venous occlusion (two). In one (7%) patient severe hypoxia and hypotension developed when the valve was crossed with a guide wire and balloon catheter. Despite successful dilatation he died 7 days after the procedure. During a mean (1 SD) follow up of 2 (1.7) years, seven (64%) of the 11 patients remained free of important restenosis. One patient required repeat dilatation three weeks after the initial procedure. In three (27%) patients restenosis developed 4-9 months after dilatation and all three had surgical valvotomy. Of the four patients initially referred for surgery three required a second operation and one required balloon dilatation. Percutaneous balloon dilatation gave effective relief of critical pulmonary stenosis in most neonates but complications and restenosis requiring surgery were common.

Balloon pulmonary valvuloplasty: results of the Valvuloplasty and Angioplasty of Congenital Anomalies Registry

Eight hundred twenty-two balloon pulmonary valvuloplasties were reported to the Valvuloplasty and Angioplasty of Congenital Anomalies Registry. Before and after systolic outflow gradients were recorded in 784 valvuloplasties, and the gradient decreased from 71 +/- 33 to 28 +/- 21 mm Hg. The sites of residual obstructions could be ascertained in 196 patients. In these, the total systolic outflow gradients decreased from 85 +/- 41 mm Hg to 33 +/- 27 mm Hg. Of this total residual gradient, 16 +/- 15 mm Hg was transvalvar and 18 +/- 24 mm Hg was infundibular. The degree to which infundibular obstruction subsequently resolved was not determined in this study. The procedure was less effective in reducing outflow gradients in patients with dysplastic valves with or without Noonan's syndrome. There were 5 major complications (0.6%), including 2 deaths (0.2%), a cardiac perforation with tamponade (0.1%) and 2 tricuspid insufficiencies (0.2%). There were 11 minor complications (1.3%) and 21 incidents (2.6%). The incidence of major complications, minor complications and incidents was inversely related to age; it was substantially higher in infants and, in particular, neonates. Balloon pulmonary valvuloplasty is a safe and effective method of lowering pulmonary outflow gradients in infants, children and adults. Small transvalvar and varied infundibular gradients commonly are present at the end of the procedure. Assessing the full effect of the procedure requires intermediate-term follow-up and assessing the duration of relief requires long-term follow-up.

Percutaneous balloon valvuloplasty of pulmonary valve stenosis, dysplasia, and residual stenosis after surgical valvotomy for pulmonary atresia with intact ventricular septum: long-term results

Eight-six children (aged 20 days to 14 years, 20 under age 1 year) underwent 94 percutaneous balloon valvuloplasty for pulmonary valve stenosis. The patients were divided into three groups: typical pulmonary valve stenosis (71), pulmonary valve dysplasia (9), and residual stenosis after surgical valvotomy for pulmonary atresia with intact ventricular septum (PAIS) (6). Each of the three groups was divided into two subgroups. In the early cases, balloon catheters with diameter 10-20% exceeding pulmonary valve annulus were used and the drop of the gradient was 39.5%. In the later cases, balloon diameters 30-40% greater than the valve anulus or double balloons were used and a drop of 66.7% in the RV-PA pressure gradient was achieved. The dilation in patients with dysplastic valve and residual stenosis after surgical valvotomy for PAIS was less effective. Doppler echocardiography was the technique used to evaluate residual gradient. Six months to 4 years follow-up demonstrated a persistent decrease of the valve gradient.

Dilatation with progressively larger balloons for severe stenosis of the pulmonary valve presenting in the late neonatal period and early infancy

Balloon dilatation in infants with severe pulmonary valve stenosis may not be a straightforward procedure once the arterial duct has closed. Balloon dilatation was attempted in three neonates and infants. In an 11 week old infant hypotension and bradycardia developed shortly after a 5 French end hole catheter was passed through the severely stenosed pulmonary valve. An emergency Waterston shunt was subsequently performed, but he died three days later. After this experience the technique was modified so that progressively larger balloons were used for dilatation in two infants, aged one and three weeks, with severe pulmonary valve stenosis in whom the arterial duct had closed. It was successful in both.

Valvuloplasty with large trefoil balloons for the treatment of congenital pulmonary stenosis

Percutaneous balloon valvuloplasty was performed in 16 children, 1 1/2 to 14 years old, with congenital pulmonary stenosis with teh use or trefoil balloons. These balloons, which consist of 3 identical angioplasty balloons, do not interrupt completely the blood flow during inflation. The size of the trefoil balloons used was 30 to 50% larger than the valve anulus. A obtain an effective pulmonary valvuloplasty in two patients with large valve anulus. The mean prevalvuloplasty systolic gradient fo 78.2 +/- 28.9 mmHg (range 40 to 140 mmHg) was reduced to 20.3 +/- 5.7 (range 10 to 30 mmHg) after valvuloplasty. No patient developed significant hypotension or bradycardia or other complications as a result of the procedure. The findings demonstrate that percutaneous balloon valvuloplasty with oversized trefoil balloons effectively treated congenital pulmonary stenosis without complications in the cases studied. The use of large trefoil instead of single balloons of a similar diameter is advantageous since they cause no significant compromise of the cardiac output during valvuloplasty.

Intraoperative balloon valvuloplasty in pulmonary valve stenosis

Balloon valvuloplasty was used in the operating room on 7 patients to visually assess the valvular changes induced by inflation of a balloon catheter. All patients had typical pulmonary valve stenosis and an associated cardiac condition which necessitated surgery. Of 23 fused commissures present, 21 were successfully opened with a single balloon inflation. In 2 patients, damage to the leaflets was observed. In 1 patient there was partial detachment and in the other a small tear was noted at the margin of one leaflet. These intraoperative results may be similar to the results obtained with percutaneous balloon valvuloplasty.

Critical pulmonary valve stenosis in patients less than 1 year of age: treatment with percutaneous gradational balloon pulmonary valvuloplasty

A new technique of percutaneous gradational balloon pulmonary valvuloplasty was used successfully in 17 infants less than 1 year of age, including four neonates, with critical congenital pulmonary valve stenosis, who would otherwise have required surgical intervention. This technique uses a sequential series of balloon catheters of gradually increasing size as a means of eventually crossing the very small valve orifice with a balloon catheter of adequate size to achieve successful pulmonary valvuloplasty. The initial dilatations were achieved with balloon catheters 2, 3, or 4 mm in diameter. Immediately after successful balloon valvuloplasty, the mean pulmonary systolic pressure gradient was reduced from 105 +/- 11 to 20 +/- 5 mm Hg. Percutaneous balloon pulmonary valvuloplasty can be performed safely with good results despite critical congenital pulmonary valve obstruction in severely ill infants.

A new type of adjustable vascular introducer for balloon valvuloplasty: technical note

To minimize vascular damage in percutaneous balloon valvuloplasty, a new type of dynamic adjustable vascular introducer has been developed which is capable of both expanding and contracting on the passage of a balloon catheter. This ability greatly reduces damage to the vessel and limits blood loss at the site of entry during the procedure. It has been used in both mitral and aortic balloon valvuloplasty.

Balloon pulmonary valvuloplasty: a review

Balloon pulmonary valvuloplasty has been used successfully over the last few years for the relief of moderate to severe valvar pulmonic stenosis in neonates, infants, children, and adults. Both immediate and intermediate term follow-up results have been well documented by cardiac catheterization studies. Electrocardiographic and echo-Doppler evaluation at follow-up is reflective of the results and may avoid the need for recatheterization. The results of balloon valvuloplasty are either comparable to or better than those reported with surgical valvuloplasty. The causes of restenosis have been identified, and appropriate modifications in the technique, particularly the recommended use of a balloon/annulus ratio of 1.2 to 1.5, should give better results than previously documented. Complications of the procedure have been minimal. Further refinement of the catheters and technique may reduce the complication rate even further. The indications for balloon valvuloplasty have not been clearly defined but should probably be similar to those used for surgical valvotomy; only patients with moderate to severe valvar pulmonic stenosis are candidates for balloon valvuloplasty. Previous surgery and pulmonary valve dysplasia are not contraindications for balloon valvuloplasty. The procedure is also applicable to pulmonary stenosis associated with other complex cardiac defects and stenosis of bioprosthetic valves in pulmonary position. Miniaturatization of balloon/catheter systems to further reduce the complication rate and documentation of favorable result at 5- to 10-year follow-up are necessary.

Pulmonary artery tears following balloon valvotomy for pulmonary stenosis

Tears involving the anterior supravalvar annulus developed in 2 children and an infant following percutaneous balloon pulmonary valvotomy using oversized balloons. The 3 patients had angiographic features of three different types of stenotic valves: usual pulmonary valve stenosis in 1, a form of dysplastic pulmonary valve with supravalvar narrowing in a second, and a doming valve in a neonate. All had a successful reduction in right ventricular outflow tract gradient following the procedure. The pulmonary arterial tears were not associated with balloon rupture or clinical symptoms. It is postulated that the relative deficiency of elastic fibers in the supravalvar commissure makes this site relatively vulnerable to intimal tearing.

Pulmonary valvoplasty--experience of 100 cases

One-hundred patients with pulmonary valve stenosis underwent pulmonary valvoplasty, their ages ranging from 1 to 59 years. The systolic gradient across the valve ranged from 47 to 260 mm Hg (97.67 +/- 41.15) prior to the valvoplasty, and from 0 to 55 mm Hg (14.72 +/- 11.40) immediately after dilatation (P less than 0.0001). The clinical follow-up of 18.2 months of 56 patients showed a tendency for the systolic thrill to disappear, the systolic murmur became softer and there was a tendency to normalization of the electrocardiogram. A hemodynamic restudy was carried out in 54 patients and the systolic gradients across the valve ranged from 21.55 +/- 23.86. Seven patients required redilatation. In patients with hypertrophy of the infundibulum prior to valvoplasty this was observed to regress, indicating that infundibular hypertrophy is reversible.

Balloon dilatation in infants and children with dysplastic pulmonary valves: short-term and intermediate-term results

This study was designed to document the results of balloon valvuloplasty in patients with dysplastic pulmonary valves and to determine whether dysplastic pulmonary valves are responsible for recurrence of stenosis after balloon pulmonary valvuloplasty. Balloon valvuloplasty in 13 patients, aged 6 days to 12 years (median 1 year), with dysplastic pulmonary valves reduced the pulmonary valve gradient from 77.2 +/- 44.2 (mean +/- SD) to 26.8 +/- 17.0 mm Hg (p less than 0.001), which remained improved (34.9 +/- 34.6 mm Hg; p less than 0.02) at 6 to 19 months' (mean 10 months) follow-up. Valvuloplasty in 43 patients without dysplastic pulmonary valves reduced the valvar gradient from 94.3 +/- 41.0 to 31.1 +/- 22.4 mm Hg (p less than 0.001) immediately after the procedure, which at 6 to 34 months' follow-up in 23 patients was 29.2 +/- 33.5 mm Hg (p less than 0.001). The right ventricular peak systolic pressures (96.2 +/- 43.3 vs 112.1 +/- 40.1 mm Hg) and pulmonary valvar gradients (77.2 +/- 44.2 vs 94.3 +/- 41.0 mm Hg) before valvuloplasty, residual right ventricular pressures (52.9 +/- 14.5 vs 56.1 +/- 24.2 mm Hg) and pulmonary valvar gradients (26.8 +/- 17.0 vs 31.1 +/- 22.4 mm Hg) immediately after valvuloplasty, and residual right ventricular pressures (59.3 +/- 30.3 vs 53.6 +/- 34.3 mm Hg) and pulmonary valvar gradients (34.9 +/- 34.6 vs 29.2 +/- 33.5 mm Hg) at follow-up catheterization were similar (p greater than 0.1) in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)