Percutaneous balloon valvuloplasty for valvar aortic stenosis in infants and children

Outcomes of uncomplicated aortic valve stenosis presenting in infants

BACKGROUND

The management of uncomplicated aortic valve stenosis presenting with critical obstruction in infants continues to be associated with significant morbidity and mortality. However, not all infants have critical obstruction, and outcomes spanning the broader spectrum of disease severity are less well defined.

METHODS

In a 12-year period, 55 infants (<3 months of age) were seen with aortic valve stenosis and with anatomy suitable for biventricular repair. Clinical, echocardiographic, angiographic, management, and outcome data were reviewed.

RESULTS

Status at presentation (median age 6 days) included signs of congestive heart failure in 20 patients, cardiovascular collapse in 5 patients, and an asymptomatic heart murmur in 30 patients. The initial echocardiogram showed reduced left ventricular function in 26% of patients, with a mean peak instantaneous gradient of 69 +/- 30 mm Hg in patients with normal function. There were 5 deaths (9%), all in patients with poor ventricular function. The initial intervention was balloon valvotomy in 24 patients and surgical valvotomy in 20 patients, with 11 patients having no intervention to date. The freedom-from-intervention rate was 69% at age 1 week, 58% at 1 month, 36% at 3 months, and 28% at 1 year. Patients without cardiovascular collapse, normal left ventricular function, and gradients <60 mm Hg at presentation (n =1 9) had better survival and longer freedom from intervention than patients with poor ventricular function or gradients >or=60 mm Hg (n = 36, P =.0001).

CONCLUSION

Most infants with aortic valve stenosis receive intervention, although this may be safely delayed in selected patients with lower initial gradients and good left ventricular function.

Recommendations of the British Paediatric Cardiac Association for therapeutic cardiac catheterisation in congenital cardiac disease

The aims of these recommendations are to improve the outcome for patients after, and to provide acceptable standards of practice of therapeutic cardiac catheterisation performed to treat congenital cardiac disease. The scope of the recommendations includes all interventional procedures, recognising that for some congenital malformations, surgical treatment is equally as effective as, or occasionally preferable to, interventional treatment. The limitations of the recommendations are that, at present, no data are available which compare the results of interventional treatment with surgery, and certainly none which evaluate the numbers and types of procedures that need to be performed for the maintenance of skills. Thus, there is a recognised need to collect comprehensive data with which these recommendations could be reviewed in the future, and re-written as evidence-based guidelines. Such a review will have to take into account the methods of collection of data, their effectiveness, and the latest developments in technology. The present recommendations should, therefore, be considered as consensus statements, and as describing accepted practice, which could be used as a basis for ensuring and improving the quality of future care.

Dilatation of congenital valvular aortic stenosis using Inoue balloon

Balloon dilatation of valvular aortic stenosis is often associated with problems of balloon seating across the valve and slippage during performance of dilatation. We describe 2 patients with congenital aortic stenosis who underwent balloon dilatation using the Inoue balloon, which to the best of our knowledge has not been reported earlier. The technique and its advantages and limitations in aortic valve dilatation are discussed.

Follow-up results of balloon aortic valvuloplasty in children with special reference to causes of late aortic insufficiency

The purpose of this study was to report on 3- to 9-year follow-up data after balloon aortic valvuloplasty in children and to investigate causes of aortic insufficiency at late follow-up. Although the immediate and short-term results of balloon aortic valvuloplasty have been well documented, little information is available on long-term follow-up results. During a 7.3-year period ending December 1992, 26 young patients, aged 6 weeks to 20 years, underwent balloon aortic valvuloplasty with resultant reduction of peak-to-peak aortic valvar gradient from 71 +/- 20 (mean +/- SD) to 25 +/- 12 mm Hg (p < 0.001). None required immediate surgical intervention. At intermediate-term follow-up, 6 (23%) of 26 had restenosis develop and underwent surgical (4 patients) or repeat balloon valvuloplasty (2 patients). Clinical and echo-Doppler data 3 to 9 years (median 6 years) after balloon valvuloplasty revealed residual peak instantaneous Doppler gradients of 26 +/- 13 mm Hg (p < 0.001), without restenosis beyond what was observed at intermediate-term follow-up. Aortic insufficiency progressed in seven patients. However, none required intervention. Actuarial intervention-free rates at 1, 2, 5, and 9 years were 80%, 76%, 76%, and 76%, respectively. Logistic regression analysis suggested that the degree of Doppler-quantitated aortic insufficiency 1 day after valvuloplasty predicts persistent aortic insufficiency at late follow-up. These data indicate that immediately successful balloon aortic valvuloplasty in children yields a residual gradient of < or = 36 mm Hg at a median of 6 years of follow-up in most patients and an intervention-free rate at 9 years of 76%. Restenosis occurs but can be treated with a repeat intervention with good results. Aortic insufficiency remains stable and does not appear to require intervention, at least during the first decade after balloon dilatation.

Independent predictors of immediate results of percutaneous balloon aortic valvotomy in children. Valvuloplasty and Angioplasty of Congenital Anomalies (VACA) Registry Investigators

Smaller patient series have not explored the independent relations between patient selection and technical factors that may impact on acute results of percutaneous balloon aortic valvotomy. To determine such relations, results from the Valvuloplasty and Angioplasty of Congenital Anomalies Registry were examined from 630 balloon aortic valvotomies in 606 patients from 23 institutions. Median age was 6.8 years (range 1 day to 18 years). The procedure could not be performed or completed in 4.1%. The left ventricular to aortic gradient was reduced by a mean +/- SD of 60 +/- 23% (p < 0.0001). Procedure-related mortality was 1.9%. A suboptimal outcome was defined arbitrarily as failure to perform the procedure, a residual gradient > or = 60 mm Hg or LV: aortic pressure ratio > or = 1.6, or major morbidity or mortality, and was noted for 17% of procedures. Independent risk factors from multiple logistic regression analyses included age < 3 months, higher preprocedure gradient, earlier procedure date, the presence of unrepaired aortic coarctation, and the use of undersized balloons. Detailed analysis revealed the optimal balloon: valve diameter ratio to be 0.9 to 1.0, with undersized balloons resulting in significant residual obstruction and oversized balloons resulting in aortic regurgitation complications. Improvements in results over time were related to increasing experience within individual institutions. Thus, percutaneous balloon aortic valvotomy provides adequate relief of obstruction, with minimal complications in most patients.

Stepwise Inoue balloon catheter valvuloplasty for congenital aortic valve stenosis: comparison with standard balloon catheter technique

Experience with stepwise balloon dilatation of congenital aortic valve stenosis using the new Inoue balloon catheter in 16 patients (aged 12 +/- 4.6 years; group II) is presented. Results are compared with those obtained in 15 patients (10 +/- 6 years; group I) in whom standard balloon catheters were used. The procedure resulted in a similar transvalvar gradient reduction in both groups (83 +/- 25 to 34 +/- 14 mmHg in group I versus 84 +/- 21 to 28 +/- 10 mmHg in group II). Significant aortic incompetence occurred in three patients from group I and in four from group II. There was no difference in the average increase in AR grade between the groups. At follow-up (group I, 24 +/- 13 months; group II, 7 +/- 3 months) there was no significant change in transaortic gradient or aortic incompetence. Balloon aortic valvuloplasty for congenital aortic stenosis carries a risk of aortic incompetence. Stepwise dilatation of the stenosis does not prevent this complication. The Inoue balloon catheter offers technical advantages.

Right subscapular artery catheterization for balloon valvuloplasty of critical aortic stenosis in infants

This study was performed to evaluate the utility and safety of catheterizing the right subscapular artery for balloon valvuloplasty of critical aortic stenosis in infants. Twenty-one patients, age 20 days to 17 months, underwent attempted valvuloplasty through the surgically exposed right subscapular artery. Five or 7Fr catheters with balloon diameters of 7 to 10 mm were used. Valvuloplasty was successfully performed using this approach in 11 patients. In 2 other patients, the subscapular artery would not accommodate the balloon angioplasty catheter (7Fr), and the arteriotomy was extended into the axillary artery. In these 13 patients, the peak systolic pressure gradient across the aortic valve was decreased from 85 +/- 23 to 33 +/- 7 mm Hg. Moderate aortic regurgitation developed in 3 patients. In the remaining 8 patients, valvuloplasty could not be performed through the right subscapular artery. In 2 patients, the right subclavian artery was anomalous and led to the descending aorta. In 6 small patients, no catheter could be advanced across the aortic valve. In 1 of these patients, a guidewire perforated a coronary sinus of Valsalva causing death. Overall, valvuloplasty using the right subscapular arterial approach was successful in 13 of 19 infants (68%) with normal right subclavian arteries, including all 10 such patients weighing > or = 5.5 kg. No clinically significant peripheral vascular complications or brachial plexus injuries occurred. Thus, the right subscapular arterial approach is an alternative route to be considered when planning balloon aortic valvuloplasty in infants.

Balloon aortic valvuloplasty for aortic stenosis in neonates, children, and young adults

Balloon aortic valvuloplasty is a safe and effective treatment for aortic stenosis in neonates, children, and young adults. The indication for balloon valvuloplasty in children is a peak systolic gradient > 70 mmHg or > 50 mmHg in any patient with symptoms. Published results indicate that the procedure results in an acute reduction in gradient ranging from 49%-70%, and this reduction appears to persist through at least an intermediate follow-up. The percentage reduction in gradient is similar for neonates as well as older children. In neonates, it is imperative to evaluate the size of the left ventricle prior to balloon valvuloplasty since mortality is highest in those with variants of hypoplastic left heart syndrome. Though morbidity and mortality is higher in the neonatal age group, the results are similar to those following surgical intervention. In children older than 1 month of age, the major complication is the development of aortic regurgitation, although it usually appears to be well-tolerated. Previous surgical valvotomy is not a contraindication to balloon aortic valvuloplasty. In the current era, we believe that balloon aortic valvuloplasty should be considered as the first option in neonates, children and young adults with significant aortic valve obstruction.

Contemporary results of balloon valvuloplasty and surgical valvotomy for congenital aortic stenosis

The purpose of this study was to compare contemporary results of balloon dilatation and surgery for valvar aortic stenosis in infants and children in the five years between August 1988 and October 1993. Thirty four children underwent attempted balloon valvuloplasty (age 1 day-16 years, weight 1720 g-68 kg) (group 1), eight of whom were neonates with critical aortic stenosis. During the same period, 17 children underwent direct surgical valvotomy (group 2) (seven neonates). Successful balloon valvuloplasty was achieved in 33 (97%) with immediate reduction in the instantaneous systolic pressure gradient from 82 to 34 mm Hg (mean). There were two deaths in this group (both neonates), the second in a preterm neonate from necrotising enterocolitis. Complications requiring intervention in group 1 were aortic regurgitation in one and femoral artery injury in two. Follow up from four months to five years showed sustained results in most cases. There were two neonatal deaths in the surgical group. When the two groups were compared there was no significant difference in mortality, morbidity, or need for reintervention within 12 months. Deaths from both groups were attributed to small left ventricles. Hospital stay was significantly shorter in group 1. It is concluded that balloon dilatation for valvar aortic stenosis is effective and safe for the entire paediatric population. The results compare favourably with those of surgery.

Critical aortic stenosis in the neonate. A comparison of balloon valvuloplasty and transventricular dilation

The optimal treatment of critical aortic stenosis in the neonate and infant remains controversial. We compared transventricular dilation using normothermic cardiopulmonary bypass and percutaneous balloon aortic valvuloplasty with respect to early and late survival, relief of aortic stenosis, degree of aortic insufficiency, left ventricular function, and freedom from reintervention. Between July 1987 and July 1993, 30 neonates and infants underwent transventricular dilation or balloon aortic valvuloplasty for critical aortic stenosis. The patients in the transventricular dilation group (n = 21) ranged in age from 1 to 59 days (mean age 18.0 days +/- 19.1 days) and the balloon aortic valvuloplasty group (n = 9) from 1 to 31 days (mean age 10.0 days +/- 9.0 days). There were no significant differences in weight, body surface area, or aortic anulus diameter between the two groups (p = 1.0). Associated cardiovascular anomalies were more common in the transventricular dilation group (48%) than in the balloon aortic valvuloplasty group (11%). After intervention, the degree of residual aortic stenosis and insufficiency was equivalent in the two groups as assessed by postprocedural Doppler echocardiography. Ejection fraction improved within both groups (transventricular dilation 39% +/- 20.2% versus 47% +/- 22.0%; balloon aortic valvuloplasty 51% +/- 16.1% versus 62% +/- 8.4%), and there was no significant difference between groups. The left ventricular mass/volume ratio increased within both groups (p < 0.05) but with no significant difference between groups (transventricular dilation 1.4 +/- 0.5 gm/ml versus 1.8 +/- 0.6 gm/ml; balloon aortic valvuloplasty 1.1 +/- 0.6 gm/ml versus 1.7 +/- 0.4 gm/ml). Early mortality in the transventricular dilation group was 9.5% and in the balloon aortic valvuloplasty group, 11.1%. There was one late death in the transventricular dilation group. Four patients from the transventricular dilation group (19%) and two patients from the balloon aortic valvuloplasty group (22%) required reintervention for further relief of aortic stenosis. We conclude that both transventricular dilation and balloon aortic valvuloplasty provide adequate and equivalent relief of critical aortic stenosis. The treatment strategy adopted should depend on other factors, including associated cardiovascular anomalies, vascular access, preoperative condition, and the technical expertise available at each institution.

Balloon dilatation (valvoplasty) as first line treatment for severe stenosis of the aortic valve in early infancy: medium term results and determinants of survival

OBJECTIVE

To assess the results of balloon dilatation of the aortic valve as first line treatment for infants presenting in the first two months of life with cardiac failure caused by severe aortic stenosis.

DESIGN

A prospective study of all such infants presenting to a single centre over a three year period.

PATIENTS

Of 14 consecutive infants aged < 2 months presenting with heart failure due to severe stenosis of the aortic valve, 12 underwent balloon dilatation of the valve. Two infants with hypoplastic left heart syndrome were excluded. Six patients had other significant cardiac malformations, nine had endocardial fibroelastosis. Four infants were moribund at presentation.

INTERVENTIONS

Balloon dilatation was performed through the femoral artery under general anaesthetic, with heparin and antibiotic prophylaxis. Maximum inflated balloon size was selected as equal to or slightly less than the diameter of the aortic valve measured echocardiographically. In two infants balloon dilatation of coexistent severe coarctation was performed at the same time.

RESULTS

Dilatation was achieved in all cases. Early survival rate (up to one month) was 75%; 50% survive up to three years. The two deaths occurring < 24 hours after dilatation probably related to the infants' poor condition at presentation and the presence of significant left ventricular hypoplasia. The other early death was due to severe mitral regurgitation from papillary muscle dysfunction. All later deaths were related to associated malformations. The difference in left ventricular size (diameter and length) measured echocardiographically at presentation between survivors and those that died is significant (p < or = 0.002). 83% of deaths occurred in infants with associated malformations. Cusp perforation occurred in one infant, which may have contributed to this patient's death. Left ventricular perforation and cardiac tamponade were treated successfully by prompt pericardiocentesis in another.

CONCLUSIONS

Balloon dilatation of the aortic valve is an acceptable first line treatment for neonates with severe symptomatic stenosis of the aortic valve. Outcome depends principally on left ventricular size and on the presence, severity, and timing of treatment of associated malformations. Severe endocardial fibroelastosis was not a risk factor for early death but may have implications for long term survival. The survival rate for this high risk group might be improved by a stratified approach where patients with adequate left ventricular size have balloon dilatation whereas those with severe ventricular hypoplasia are managed like patients with the hypoplastic left heart syndrome.

Initial experience with balloon dilatation of supravalvar aortic stenosis

Primary balloon dilatation of supravalvar aortic stenosis was attempted in three patients: a 20 year old woman, a seven month old boy, and a 12 year old girl. Balloon catheters (Mansfield) with diameters of 25 mm, 8 mm, and 15 mm were used in the three patients respectively. The systolic pressure gradient across the aortic narrowing decreased considerably and the diameter of the constricted area increased significantly. Balloon dilatation was feasible and provided good immediate results and sustained relief of supravalvar aortic stenosis in these three patients. However, a larger study is needed to establish the place of this procedure in treatment.

Prograde double balloon dilation of congenital aortic valve stenosis: a case report

A new method for prograde balloon dilation of severe congenital aortic valve stenosis is described. Two TEGwire balloons were used prograde through bilateral femoral venous sheaths. Excellent hemodynamic results were achieved, without the need for retrograde left heart catheterization and femoral arterial sheath placement.

Balloon valvuloplasty for congenital aortic valve stenosis in an infant and children

Percutaneous balloon aortic valvuloplasty (BAV) was performed in 14 patients, including one critically ill infant with congenital valvular aortic stenosis (AS). BAV was effective in 13 patients (except the infant). The peak systolic pressure gradient between the left ventricle (LV) and the ascending aorta decreased from 76.6 +/- 21.6 to 29.5 +/- 15.3 mmHg (P less than 0.001). Follow-up cardiac catheterization was performed for eight patients between 1 and 3 years (1.6 +/- 1.1 years) after BAV. Restenosis was found in only one patient, and the efficacy of BAV continued significantly. Aortic regurgitation developed or increased in severity in 5 of 13 children immediately after BAV. Any other severe complication was not observed. Dilatation by BAV was not sufficient for the infant with critical AS, and acute myocardial infarction (AMI) in the lateral wall of the LV occurred during the BAV procedure. The infant died 3 days after the procedure due to AMI. It was concluded that the retrograde double balloon technique was superior to the retrograde single balloon technique. In two cases, the single balloon technique was ineffective because it was impossible to fix the balloon at the aortic annulus. However, the double balloon technique was effective in every patient. BAV is effective for AS in children, and an optional repeat trial may enable BAV to be the first choice for AS. Although BAV may be effective for neonates and infants with critical AS as an emergency treatment, much attention must be paid during the procedure.

Intermediate-term effectiveness of balloon valvuloplasty for congenital aortic stenosis. A prospective follow-up study

BACKGROUND

Percutaneous balloon valvuloplasty has proven to be acutely effective in the treatment of congenital valvar aortic stenosis; however, the intermediate- and long-term effectiveness of the procedure remain to be documented.

METHODS AND RESULTS

To assess the intermediate-term effectiveness of balloon valvuloplasty, repeat catheterization was performed in 27 of 30 children 1.7 +/- 0.1 years after balloon valvuloplasty for congenital aortic stenosis (AS). In 33 children the peak AS gradient was reduced acutely by 55% from 77 +/- 4 to 35 +/- 3 mm Hg (p less than 0.001), and left ventricular systolic pressure was reduced from 176 +/- 4 to 138 +/- 4 mm Hg (p less than 0.001). Despite a technically adequate valvuloplasty procedure, three patients had inadequate relief of obstruction and required complex surgical intervention. Twenty-seven of the 30 patients available for late reevaluation (90%) enrolled in the follow-up study. The peak AS gradient remained significantly reduced compared with that present before valvuloplasty (29 +/- 3 versus 77 +/- 4 mm Hg, p less than 0.001). Furthermore, there was no difference in peak AS gradient at follow-up compared with that immediately after valvuloplasty. The greatest increase in gradient at reevaluation was 14 mm Hg. Twenty of 27 patients (74%) had no change in the degree of aortic insufficiency at follow-up compared with that present before valvuloplasty. At follow-up, 16 patients had no aortic insufficiency at all, and only two had moderate-to-severe (3-4+) insufficiency. Femoral artery injury was documented in four patients, three of whom were under 12 months of age at valvuloplasty.

CONCLUSIONS

Balloon aortic valvuloplasty provides safe and effective intermediate-term gradient relief without early restenosis in children and adolescents with congenital AS.

Balloon dilatation of the aortic valve in the fetus: a report of two cases

Because they had irreversible damage to the left ventricular myocardium none of 12 patients with critical aortic stenosis diagnosed prenatally survived after postnatal treatment. This experience prompted three attempts at intrauterine balloon dilatation of the aortic valve in two fetuses with this condition. On each attempt the balloon catheter was successfully delivered to the left ventricle. In the first fetus the aortic valve was not crossed and the fetus died the next day. In the second fetus the balloon was correctly positioned across the aortic valve and inflated in the valve ring. After delivery, a further balloon angioplasty was performed; this relieved the stenosis but the patient died five weeks later from persisting left ventricular dysfunction related to endocardial fibroelastosis. Balloon angioplasty is feasible in fetal life but the prognosis depends on the ability of the relief of stenosis to limit, prevent, or allow regression of left ventricular damage before delivery.

Balloon valvuloplasty for critical aortic stenosis in the newborn: influence of new catheter technology

Between 1986 and July 1990, balloon valvuloplasty was attempted in eight newborns (less than 28 days of age) with isolated critical aortic valve stenosis. Balloon valvuloplasty could not be successfully accomplished in any of the three infants presenting before 1989. Since March 1989, when improved catheter technology became available, all five neonates presenting with critical aortic stenosis were treated successfully by balloon valvuloplasty. A transumbilical approach was utilized in all four infants in whom umbilical artery access could be obtained. One newborn who was 25 days of age underwent transfemoral balloon valvuloplasty. Balloon valvuloplasty was immediately successful in all five newborns, as evidenced by a decrease in valve gradient and improvement in left ventricular function and cardiac output. Peak systolic gradient was reduced by 64% from 69 +/- 8 to 25 +/- 3 mm Hg (p = 0.005). Left ventricular systolic pressure decreased from 128 +/- 9 to 95 +/- 9 mm Hg (p = 0.02) and left ventricular end-diastolic pressure decreased from 20 +/- 2 to 11 +/- 1 mm Hg (p = 0.02). Moderate (2+) aortic regurgitation was documented in two infants after valvuloplasty. The time from first catheter insertion to valve dilation averaged 57 +/- 14 min (range 26 to 94) and the median length of the hospital stay was 4 days. With the use of recently available catheters, the transumbilical technique of balloon valvuloplasty can be performed quickly, safely and effectively in the newborn with critical aortic stenosis. It does not require general anesthesia, cardiopulmonary bypass or a left ventricular apical incision and it preserves the femoral arteries for future transcatheter intervention should significant aortic stenosis recur.

Left ventricular mid-cavitary obstruction after balloon dilation in isolated aortic valve stenosis in children

A hyperdynamic left ventricle can lead to post-dilation mid-cavitary obstruction in the absence of any preballoon mid-cavitary obstruction in children with aortic valve stenosis. The purpose of this study was to define the incidence and course of post-dilation mid-cavitary obstruction. We reviewed the catheterization and echocardiographic data of 35 patients, ages 3 days to 18 years (mean = 7.9 years), with isolated aortic valve stenosis who underwent balloon dilation with a fall in aortic valve gradient to less than 20 mm Hg. Post-dilation mid-cavitary obstruction was suspected from post-dilation left ventricular angiogram and was quantitated by echocardiographic and Doppler examinations performed immediately after dilation and in a 1-3 month follow-up period. Continuous wave Doppler directed by color flow Doppler was used for evaluation and differentiation of post-dilation mid-cavitary obstruction and residual aortic valve stenosis. Three children (3/35 [9%]) all under 2 years of age developed post-dilation mid-cavitary obstruction immediately after dilation. The obstruction within the cavity resolved spontaneously in all three patients.

CONCLUSIONS

1) Post-dilation left ventricular mid-cavitary obstruction can occur in children under 2 years of age after balloon dilation of severe aortic valve stenosis, and 2) total regression of post-dilation mid-cavitary obstruction occurs spontaneously in all patients.

Transesophageal echocardiographic guidance of transcatheter closure of atrial septal defect

Transcatheter closure of atrial septal defect (ASD) was accomplished in 10 of 11 patients aged 13 months to 46 years (weight range 11 to 77 kg). Transesophageal echocardiography (TEE) was used simultaneously with fluoroscopic imaging in 4 of these patients aged 4.5 to 46 years (weight range 19 to 77 kg). TEE was used to ascertain defect size, position and number of defects and to ascertain appropriate seating of the defect occluder within the atrial defect. In 2 patients TEE-assisted transcatheter ASD closure was accomplished after previous attempts at transcatheter ASD closure, unaided by TEE, had been unsuccessful. The only unsuccessful ASD closure procedure occurred in the smallest patient in the series (an 11-kg 13-month-old), a child who was too small to undergo TEE using our 11-mm diameter endoscopic probe. The concomitant use of TEE with fluoroscopic imaging provides information that is unique and complementary and may improve the efficacy and safety of the transcatheter technique for ASD closure. The recent availability of a 7-mm diameter TEE probe will extend the use of TEE into the infant age group and may decrease the discomfort and potential morbidity of TEE in older patients.

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.

Carotid artery approach for balloon dilation of aortic valve stenosis in the neonate: a preliminary report

Balloon valvuloplasty in neonates with severe aortic valve stenosis is limited by difficulties in catheter manipulation around the arch and across the valve and by the risk of femoral artery complications. A right common carotid artery cutdown was utilized for balloon aortic valvuloplasty in five neonates 1 to 20 days of age, weighing 3.1 to 3.9 kg. Standard balloon valvuloplasty was performed through a 6F sheath inserted in the right carotid artery. The arteriotomy was repaired at the end of the procedure. Mean left ventricular systolic pressure was reduced from 142 to 97 mm Hg, with a decrease in mean peak systolic pressure gradient from 76 to 33 mm Hg. Only one patient developed mild aortic regurgitation. One patient with a hypoplastic left ventricle died, and one patient required open valvotomy. All four survivors have a normal carotid pulse and no neurologic sequelae. Two of these patients required repeat balloon dilation to treat residual aortic valve stenosis at 8 and 10 months of age, respectively. Balloon valvuloplasty using a carotid artery approach is feasible and was safe in five neonates with severe aortic valve stenosis.

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

Data from 204 children and infants who underwent aortic balloon valvuloplasty between 1982 and 1986, reported to the Valvuloplasty and Angioplasty of Congenital Anomalies Registry, were reviewed. Valvuloplasty was successful in 192 of 204 children, reducing the peak systolic left ventricular ejection gradient from 77 +/- 2 to 30 +/- 1 mm Hg, p less than 0.001. The same degree of aortic stenosis gradients reduction was noted in both the 38 children under 1 year of age and in the 166 children over 1 year of age. Significant complications included death, aortic regurgitation and femoral artery thrombosis or damage. The incidence of these complications correlated with the age of the child, the ratio of valvuloplasty balloon size/anulus size, or both. The data suggest that percutaneous balloon valvuloplasty provides effective acute relief of valvar aortic stenosis in both infants and children. However, long-term follow-up data are necessary before balloon valvuloplasty can be established as a treatment of choice for congenital valvar aortic stenosis.

Hemodynamics and coronary blood flow during experimental aortic valvuloplasty: comparison of the dual versus the single catheter methods

During thoracotomy 12 anesthetized swine were instrumented and valvuloplasty catheters were positioned at the aortic anulus. Thirty-second occlusions of the left ventricular outflow tract were performed with a single catheter (n = 34) and with simultaneous inflation of dual catheters (n = 47). Left anterior descending coronary artery blood flow fell to minimums of 15% of baseline flow (SD 13.9%) during single balloon occlusion and to 63.8% of baseline flow (SD 22.8%) during dual balloon occlusion. Main pulmonary artery flow fell to minimums of 13.6% of baseline flow (SD 17.3%) during single balloon occlusion and to 66.9% of baseline flow (SD 18.3%) during dual balloon occlusion. Femoral artery systolic pressure dropped to 20.1% of baseline pressure (SD 5.6%) during single balloon occlusion and to 82.6% of baseline pressure (SD 8.1%) during dual balloon occlusion. During single balloon occlusion, 8.5 (SD 3.5) premature ventricular contractions were observed and 2.8 (SD 1.6) premature ventricular contractions occurred during dual balloon occlusion. After deflation of the valvuloplasty catheters, the time to return of baseline flow in the left anterior descending coronary artery was 28.4 second (SD 23.2 seconds) with the single balloon method and 4.8 seconds (SD 3.7 seconds) with the dual balloon method. All of these differences were statistically significant (p less than .001). During occlusion of the left ventricular outflow tract by dual valvuloplasty catheters, there were better hemodynamics, higher coronary blood flows, and fewer premature ventricular contractions than during occlusion by a single catheter. After occlusion by dual catheters, returns to baseline coronary flows were more rapid than after single catheter occlusions. These data may have application to clinical aortic valvuloplasty.

Intermediate-term follow-up results of balloon aortic valvuloplasty in infants and children with special reference to causes of restenosis

Sixteen infants and children with valvular aortic stenosis underwent percutaneous balloon aortic valvuloplasty over a 36-month period ending August 1988. The mean systolic pressure gradient across the aortic valve decreased from 72 +/- 21 (mean +/- standard deviation) to 28 +/- 13 mm Hg (p less than 0.001) immediately after valvuloplasty; the degree of aortic insufficiency did not significantly increase. Follow-up catheterization (in 10 patients) and Doppler data (in all 16 patients) were available 3 to 32 months (mean 12 months) after valvuloplasty and revealed a residual aortic valvular gradient of 37 +/- 23 mm Hg, which continues to be significantly lower (p less than 0.001) than that before valvuloplasty. There was no increase in aortic insufficiency. On the basis of follow-up data, the 16 children were divided into 2 groups: group I with good results (gradients less than or equal to 49 mm Hg), 12 patients; and group II with poor results (gradients greater than or equal to 50 mm Hg), 4 patients. All 4 patients in group II required repeat balloon valvuloplasty or surgical valvotomy; none from group I required these procedures. Seventeen general, anatomic, physiologic and technical variables were examined by a multivariate logistic regression analysis to identify factors associated with restenosis; these risk factors were: age less than or equal to 3 years; and immediate aortic valvular gradient after valvuloplasty greater than or equal to 30 mm Hg. The immediate and intermediate-term follow-up results of balloon aortic valvuloplasty are encouraging. Recognition of the risk factors may help identify potential candidates for recurrence.(ABSTRACT TRUNCATED AT 250 WORDS)

Neonatal critical valvar aortic stenosis. A comparison of surgical and balloon dilation therapy

Balloon aortic valvotomy (BAV) is an alternative to surgical valvotomy in infants and children. We compared BAV in 16 consecutive neonates (1985-1988) to surgical valvotomy in a prior group of 16 consecutive neonates (1978-1984). Both groups were comparable in terms of age, weight, hemodynamic data, left ventricular size, and associated lesions. There were six early and one late deaths after surgery. Five out of six neonates requiring a second operation died. Left ventricular size (measured in 13 neonates) had some influence on survival after surgery: three of three with small or hypoplastic left ventricles and three of 10 with normal-sized left ventricles died. After BAV, there were three early deaths, two patients who underwent stage I palliation of hypoplastic left heart syndrome, and two late deaths. As with surgical valvotomy, left ventricular size seemed to influence survival after BAV: five of six with small or hypoplastic left ventricles died or underwent stage I palliation for hypoplastic left heart syndrome and two of nine with normal-sized left ventricles died. At follow-up (26 +/- 17 months) in six patients in the surgical group, the peak systolic ejection gradient (PSEG) was 52.2 +/- 23 mm Hg and left ventricular end-diastolic pressure (LVEDP) 18.2 +/- 5.2 mm Hg. Aortic regurgitation was mild in five and moderate in the sixth patient. At follow-up (17.6 +/- 7.8 months) in nine patients in the balloon dilation group, the PSEG was 45.6 +/- 11 mm Hg in five patients at catheterization and 43.8 +/- 22.9 mm Hg in four patients by echocardiography-Doppler. Aortic regurgitation was mild in three and absent in the other six patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Balloon dilatation of congenital aortic valve stenosis in infants and children: short term and intermediate results

Percutaneous balloon dilatation of the aortic valve was attempted in 25 consecutive patients with stenosis. The aortic valve diameters were normal for age. The balloon catheters were placed retrogradely, and their diameters were within 1-2 mm of the valve diameter and 3 (13 patients) or 6 cm (recent 12 patients) long. After dilatation the pressure gradients across the aortic valve were reduced significantly and the valve areas, measured in 10 patients, increased. Aortic regurgitation was detected in six patients before (grade I) the procedure and in 15 patients (6 grade I, 6 grade II, 3 grade III) after the procedure. In one patient the aortic valve could not be crossed and in three there was no reduction in the pressure drop. Nine patients have a sustained reduction in Doppler assessed gradients. There were vascular complications in 12 and these required surgical intervention in three patients. Balloon dilatation seems to be an effective short term palliative procedure in patients with congenital stenosis of the aortic valve.

Balloon valvuloplasty for recurrent aortic stenosis after surgical valvotomy in childhood: immediate and follow-up studies

The immediate and intermediate-term effects of balloon valvuloplasty were assessed at cardiac catheterization in nine children with recurrent stenosis after a previous surgical aortic valvotomy. At valvuloplasty the patients ranged in age from 0.35 to 16 years and had undergone surgical valvotomy 0.3 to 12.5 years previously. Balloon valvuloplasty immediately reduced the peak systolic aortic stenosis gradient by 53%, from 88 +/- 9 (mean +/- SEM) to 41 +/- 6 mm Hg (p = 0.004). The left ventricular systolic pressure was reduced from 189 +/- 8 to 157 +/- 8 mm Hg (p = 0.001) and the left ventricular end-diastolic pressure from 17 +/- 1 to 14 +/- 2 mm Hg (p = 0.025). The heart rate and cardiac index remained unchanged. Before valvuloplasty, one patient had 1 + and two patients had 2+ aortic insufficiency. In six of nine patients, balloon valvuloplasty caused no change in the degree of valvular insufficiency. Two patients had a 1 + increase (from 0 to 1 + insufficiency in both), and one patient with no insufficiency developed 2+ aortic insufficiency. Elective follow-up catheterization was performed 0.8 to 2.5 years (mean 1.5 +/- 0.2) after valvuloplasty. At follow-up, the peak aortic stenosis gradient remained significantly reduced from the gradient before valvuloplasty (37 +/- 5 versus 85 +/- 10 mm Hg, p = 0.002). The gradient had not changed significantly from that measured immediately after valvuloplasty (37 +/- 5 versus 38 +/- 5 mm Hg, p = 0.75). At follow-up, aortic insufficiency had decreased from that immediately after valvuloplasty in three patients and had increased in two.(ABSTRACT TRUNCATED AT 250 WORDS)

Balloon valvuloplasty 1988: a review

Catheter balloon valvuloplasty is a procedure which has been applied in stenotic lesions of all four cardiac valves in the last several years. This review discusses available data regarding the mechanism of effect, risks, and clinical utility of balloon valvuloplasty as it is applied to stenotic lesions of the pulmonic, mitral and aortic valves.

Balloon dilatation of the aortic valve for congenital aortic stenosis in childhood

Balloon dilatation of the aortic valve was attempted in 34 consecutive children aged 16 months to 17 years (median 7 years), weight range 9-60 (median 22) kg. Previous surgical valvotomy had been performed in two patients (twice in one of them). The valve was not crossed in one patient. In the remaining 33 patients the pressure difference between the left ventricle and the ascending aorta during systole was reduced from 71 (30) to 28 (19) mm Hg. In 24 patients recatheterisation 2-19 (mean 9) months later showed gradients that were similar to those immediately after balloon dilatation (35 (20) v 31 (20) mm Hg). The two patients with the highest residual gradients immediately after balloon dilatation showed a spontaneous reduction in gradient at repeat catheterisation, whereas the patient who had twice had previous surgical valvotomy showed an increase in gradient from 37 to 99 mm Hg over nine months and required aortic root replacement. Balloon dilatation was repeated in two patients and this caused a further reduction in gradient. New aortic regurgitation occurred in nine (27%) patients (grade I, 8; grade II, 1) and aortic regurgitation was exacerbated (grade I to II) in two of the nine with pre-existing aortic regurgitation. External iliac artery avulsion occurred in one (3%) patient and two (6%) required intravenous streptokinase because the femoral artery became occluded. There were no other complications. Open valvotomy was performed in the child in whom the valve was not crossed, but no other child required aortic valve operation. Balloon dilatation of the aortic valve gave reasonable short term palliation and was well tolerated. It is an alternative to surgical valvotomy for initial palliation of congenital aortic stenosis in many children.

Comparison of single and double balloon valvuloplasty in children with aortic stenosis

To compare the effectiveness of the single and double balloon techniques, the short-term results of percutaneous balloon valvuloplasty were assessed in two consecutive groups of children with valvular aortic stenosis. In 16 children (aged 3 months to 17 years) the single balloon technique was utilized; the ratio of balloon diameter to valve anulus diameter was 0.96 +/- 0.03 (mean +/- SEM). In 11 children (aged 3 months to 21 years) the double balloon technique was utilized in which two balloons are positioned across the valve and inflated simultaneously; the ratio of the balloon diameter sum to valve anulus diameter was 1.32 +/- 0.05. The groups were similar in age, weight, cardiac output, prevalvuloplasty gradient and valve anulus diameter. Overall, valvuloplasty reduced the peak systolic gradient by 53% from 80 +/- 4 to 38 +/- 3 mm Hg (p less than 0.0001). In the single balloon group the gradient decreased from 82 +/- 6 to 46 +/- 4 mm Hg (p less than 0.0001), whereas in the double balloon group the gradient decreased from 76 +/- 5 to 26 +/- 4 mm Hg (p less than 0.0001). The peak systolic gradient after valvuloplasty was 43% lower in the double balloon group (p less than 0.01). Furthermore, the single balloon technique reduced the gradient by an average of 43% compared with a 67% reduction with the double balloon technique (p less than 0.001). The short-term complications of valvuloplasty were similar, with an increase in aortic insufficiency occurring in three children in each group.(ABSTRACT TRUNCATED AT 250 WORDS)

Balloon dilation of congenital aortic valve stenosis. Results and influence of technical and morphological features on outcome

We evaluated dilation technique (n = 80) and aortic valve morphology by two-dimensional echocardiography (n = 58) in patients with congenital aortic valve stenosis to determine their influence on outcome. Patients' age (9 +/- 9 years; range, 1 day-39 years) and a history of surgical valvotomy did not influence outcome. The number of dilating balloons (one vs. two) and balloon: annulus ratio based on the largest balloon used in each case (97 +/- 12%; range, 71-133%) did not demonstrably influence the percent reduction in valvar gradient. In contrast, with a balloon: annulus ratio greater than 100%, the incidence (26%) of significant, dilation-induced aortic regurgitation was higher than occurred when the ratio was equal to or less than 100% (11%). Fifty bicommissural and eight unicommissural valves were identified echocardiographically. Relief of obstruction was associated with apparent commissural division in 24 of 32 patients with suitable postdilation studies. The sites of fusion and stenosis relief did not influence percent reduction in valvar gradient. Substantial increases in aortic regurgitation (greater than three of five grades) occurred in three of eight unicommissural and one of 50 bicommissural valves. The presence of a thick valve was associated with a slightly lower gradient reduction (53 +/- 12%) than thin and pliant valves (63 +/- 24%) (p greater than 0.05). Unlike all other congenital lesions we have studied, dilation technique and balloon size appeared to have a lesser influence on percent reduction in valvar gradient in congenital aortic stenosis, although balloon: annulus ratio influences the increase in aortic regurgitation. Valve morphology appears to assist with predicting the outcome of dilation.

Interventional catheterization in pediatric congenital and acquired heart disease

The present status of catheter-directed therapy in pediatric congenital and acquired heart disease is reviewed. Balloon pulmonary valvotomy, established as the procedure of choice for children and adults with isolated pulmonary stenosis, has now been extended to neonates with critical pulmonary stenosis. Balloon mitral and aortic valvotomy are being performed for congenital and acquired stenoses, although indications and optimal techniques remain to be established. Balloon angioplasty of coarctation effectively relieves obstruction in native and post-operative aortic arch stenoses, but remains controversial due to late aneurysm formation. Balloon angioplasty of branch pulmonary artery hypoplasia and stenosis, despite a relatively low success rate and significant complications, remains the procedure of choice due to lack of better therapeutic options. Transcatheter closure of congenital and acquired vessels and defects is being performed with increasing frequency. Embolization of aortopulmonary collaterals and shunts using Gianturco coils is safe and effective in selected patients. Although Rash-kind umbrellas are most commonly used for closure of a patent ductus arteriosus, their use, especially in closing intracardiac defects, remains investigational.