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Ann Thorac Surg 1998;65:1758-1762
© 1998 The Society of Thoracic Surgeons

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Original articles: cardiovascular

Late Results and Reintervention After Aortic Valvotomy for Critical Aortic Stenosis in Neonates and Infants

^a Divisions of Pediatric Cardiothoracic Surgery and Cardiology, Departments of Surgery and Pediatrics, Primary Children’s Medical Center and the University of Utah, Salt Lake City, Utah, USA

Accepted for publication January 22, 1998.

Address reprint requests to Dr Hawkins, Pediatric Cardiothoracic Surgery, Primary Children’s Medical Center, 100 N Medical Dr, Salt Lake City, UT 84113
e-mail: (jhawkins{at}med.utah.edu)

	Abstract

Top Abstract Introduction Patients and methods Results Comment References

 
Background. Many centers have adopted balloon valvuloplasty for treatment of infants with critical aortic stenosis because of historically poor early results and a lack of long-term results with surgical valvotomy. We evaluated our results with open aortic valvotomy over the past decade, specifically examining factors influencing survival and reintervention in the current era.

Methods. From 1986 to 1996, 37 infants in the first 3 months of life underwent open aortic valvotomy for critical aortic stenosis. All patients underwent cardiopulmonary bypass, valvotomy, and valve debridement under direct vision with standard techniques.

Results. Early mortality was 11% (4 of 37, 70% confidence limit 7% to 20%) and all early deaths were in neonates less than 2 weeks of age. Late death occurred in 6 patients a mean of 10 ± 12 months (range, 2 to 36 months) after valvotomy. Actuarial survival, including operative deaths was 92% ± 6% at 1 month, 78% ± 9% at 1 year, and 73.4% ± 10% at 10 years. In a multifactorial regression analysis, the best predictors of death were the presence of endocardial fibroelastosis and small body surface area and the best predictor of the need for late reintervention was preoperative aortic annular size. Thirteen patients required reintervention: repeat operation in 7 patients, balloon valvuloplasty in 3 patients, and both balloon valvuloplasty and reoperation in 3 patients. Actuarial freedom from reintervention postoperatively is 97% ± 3% at 1 month, 73% ± 9% at 1 year, and 55% ± 11% at 10 years. Reintervention was for recurrent left ventricular outflow obstruction in 9 patients and mixed aortic stenosis and aortic insufficiency in 4. Echocardiography 4.3 ± 2.5 years after aortic valvotomy in survivors who have not required reintervention (n = 20) revealed a Doppler peak instantaneous systolic gradient of 37 ± 14 mm Hg and mild or less aortic regurgitation in 16 patients and moderate aortic regurgitation in 4 patients.

Conclusions. Current surgical results with critical aortic stenosis in the neonate and young infant are acceptable in terms of both late survival, reintervention, and functional results in the majority of patients. Newer interventions, such as balloon valvuloplasty, should be carefully evaluated for long-term results and should be compared more appropriately to current surgical results to determine the best treatment modality for the neonate and infant with critical aortic stenosis.

	Introduction

Top Abstract Introduction Patients and methods Results Comment References

 
Critical aortic stenosis (AS) in neonates and young infants is a difficult clinical problem regardless of the therapeutic approach. Historically open surgical valvotomy has had mixed results with early mortality rates ranging from 9% to 59% [1–8]. This has led many centers to adopt percutaneous balloon valvuloplasty as the procedure of choice over surgical valvotomy for the treatment of congenital AS for children of all ages [9–13]. Although this approach has met with some success, the long-term results of both balloon aortic valvuloplasty and open surgical valvotomy are lacking.

Our approach to the neonate and small infant with critical AS over the years has been almost exclusively with open surgical valvotomy. The purpose of this study was to take advantage of our relatively uniform approach and examine late functional results and reintervention after surgical valvotomy. This will allow a reference point for comparison of newer interventions for critical aortic stenosis such as balloon valvuloplasty, transventricular closed valvotomy, and neonatal pulmonary autograft procedures.

	Patients and methods

Top Abstract Introduction Patients and methods Results Comment References

 
We reviewed hospital and outpatient records of all neonates and infants 90 days of age who underwent open aortic valvotomy at Primary Children’s Medical Center between January 1986 and December 1996. The only patients excluded from this study were those that had preoperative recognition of left ventricular (LV) hypoplasia sufficient to preclude a biventricular repair and patients who underwent primary balloon aortic valvuloplasty. In general, if the patient had both an aortic valve annulus diameter less than 5 mm and a calculated LV end-diastolic volume less than 20 mL/m² [14], then the patient did not have an attempt at biventricular repair with a valvotomy. During the time period of this study a total of 8 additional patients less than 90 days of age underwent primary balloon aortic valvuloplasty for critical AS. Six of these patients were chosen for primary balloon valvuloplasty early in the total experience and at the discretion of the attending cardiologists, with 4 survivors. Two additional patients underwent balloon valvuloplasty because of an annulus size of 4 mm or less and adequate LV volume and function. Both of these patients suffered a dissection of the ascending aorta and underwent urgent ascending aortic repair and aortic valvotomy. These two patients subsequently died 24 and 43 days postoperatively of chronic low cardiac output states with multisystem organ failure.

A total of 37 consecutive patient records were reviewed for the 11-year study period. Twenty-four of the patients were in the first month of life and 13 patients were between 1 and 3 months of age at operation. The mean age at operation was 26 days and the median age at operation was 14 days (range, 2 to 86 days). Other patient characteristics are included in Table 1. Patients with severe hypoplastic left heart structures were generally selected for univentricular repair, but there were 3 patients with an aortic annulus less than 6 mm, 4 with a mitral valve diameter less than 8 mm, 4 with an LV ejection fraction less than 0.20, and 5 patients with an LV end-diastolic volume less than 20 mL/m². All patients underwent preoperative two-dimensional and Doppler echocardiography and many early patients underwent preoperative cardiac catheterization. Operation was undertaken if the infant had critical AS as defined by ductal dependency or congestive heart failure with severe symptoms.

Postoperative follow-up was obtained in all patients by direct visits with attending cardiologists. Complete two-dimensional and Doppler echocardiograms were obtained in all survivors. Aortic valve gradient was estimated using continuous wave Doppler interrogation from multiple views. Postoperative aortic regurgitation was evaluated by color Doppler mapping and graded as mild, moderate, or severe according to previously described methods [15]. Echocardiographic indices were determined based on the preoperative echocardiogram and included determination of LV volume, aortic annulus and root diameters, mitral valve area, LV mass and mass/volume ratio, LV shortening fraction and ejection fraction, and end-systolic wall stress. Reintervention was defined as any reoperation or balloon aortic valvuloplasty and the earliest reintervention was chosen when 1 patient had both operative and balloon aortic valvuloplasty reintervention.

Statistical methods
Normally distributed data are presented as mean ± standard deviation. Nonnormally distributed data are described as median and range. Survival and event-free survival are calculated and presented by the method of Kaplan and Meier [16]. Cox’s proportional hazard model was used in both a single factor and multifactorial analysis of survival and event-free survival (freedom from reintervention) [17]. Factors analyzed for effect on survival and event-free survival included aortic annulus size, preoperative Doppler LV outflow gradient, mitral valve area, presence of mitral insufficiency LV end-diastolic dimension, LV end-diastolic volume, LV mass, LV ejection fraction, age at operation, end-systolic wall stress, presence of echocardiographic evidence of endocardial fibroelastosis, and presence of coexisting cardiac anomalies (exclusive of patent ductus arteriosus).

	Results

Top Abstract Introduction Patients and methods Results Comment References

 
Hospital operative mortality over the 11-year study was 4 of 37 patients (10.8%) (70% confidence limit, 7% to 20%). Three of the operative deaths occurred at 16, 22, and 27 days postoperatively. All 3 of these patients died of low cardiac output with varying degrees of residual LV outflow obstruction. The fourth operative mortality occurred 45 days after the initial aortic valvotomy after a Konno procedure using a prosthetic valve and occurred because of residual LV outflow obstruction. The 6 late deaths occurred a median of 6 months after aortic valvotomy. One patient died suddenly at home of unknown causes 6 months after valvotomy. Five of the other 6 late deaths occurred in patients with residual LV outflow obstruction who had undergone surgical reintervention (4 patients) and balloon valvuloplasty (1 patient). Actuarial survival with 70% confidence limits and including operative deaths is shown in Figure 1. The Cox univariate analysis showed that the best predictor of mortality (both early and late) after aortic valvotomy was presence of endocardial fibroelastosis (p = 0.0004) and a small body surface area (p = 0.0028). In the multifactorial analysis, the presence of endocardial fibroelastosis emerged as the best predictor of early or late death.

View larger version (14K): [in this window] [in a new window]   Fig 1. Actuarial survival of 37 neonates and infants undergoing open valvotomy with hypothermic cardiopulmonary bypass.

View larger version (17K): [in this window] [in a new window]   Fig 2. Reintervention-free survival of 37 neonates and infants undergoing open valvotomy with hypothermic cardiopulmonary bypass. Reintervention is defined as the first surgical reintervention or balloon valvuloplasty.

View larger version (15K): [in this window] [in a new window]   Fig 3. Event-free survival of 37 neonates and infants after open aortic valvotomy. An adverse event is defined as any early or late death, reintervention, or postoperative episode of endocarditis.

	Comment

Top Abstract Introduction Patients and methods Results Comment References

 
In recent years the standard treatment for critical AS in the neonate and young infant has changed from surgical valvotomy to balloon aortic valvuloplasty in many centers [9–13]. In many institutions balloon aortic valvuloplasty appears to offer good early relief of LV outflow tract obstruction at a low risk, but with very little information on long-term follow-up and the need for late reintervention. Likewise there have been reports of acceptable initial mortality in surgical valvotomy series, but there is little information regarding long-term survival and reintervention. In our own institution, we have questioned whether we should change to balloon aortic valvuloplasty for the initial intervention in neonates and infants. Previously, we tried primary balloon valvuloplasty in 6 infants, but we were somewhat disappointed with the early results, returning to aortic valvotomy. This contemplated change to balloon valvuloplasty again actually stimulated the initiation of this study so we could make a more accurate decision regarding a change in therapeutic approaches. We chose 1986 as an arbitrary starting date as this was when balloon aortic valvuloplasty was introduced for older children with AS at our institution and would allow a contemporary analysis of results with surgical valvotomy. Our study has the advantage of following a group of very young infants after a relatively standardized operative approach over a relatively long period of time (11 years). This contemporary series then can serve as a reference point when analyzing long-term results with newer therapies such as balloon aortic valvuloplasty.

The early mortality rate for surgical aortic valvotomy has ranged between 9% and 59%, even in recent years [1–8]. The mortality rate in our series is certainly quite low by older standards, but undoubtedly there is some degree of selection that has occurred over the years as we have learned which patients have ventricular size and volume sufficient to undergo valvotomy rather than Norwood reconstruction or transplantation. We found small body surface area and the presence of echocardiographic evidence of endocardial fibroelastosis to be the strongest predictors of mortality, either early or late. This is in agreement with other studies that have found small patient size or young age and endocardial fibroelastosis [8, 19] to be predictors of death. We did not find LV volume to be an independent predictor of death as others have [20], but this is likely due to the fact that we did not have many patients with small LV volumes who underwent this attempt at a biventricular repair and the relative weakness of ventricular volume as a definitive predictor in this entity [20]. Kitchiner and associates [7] found a small aortic annulus to be a predictor of an adverse outcome as we found it to be a predictor of late reintervention. The late survival in this study was good with a 73% survival at 10 years, including operative mortality. This compares favorably to the late survival reported by others using surgical valvotomy with Messmer and colleagues [5] reporting a 10-year survival of 78% and Gildein and colleagues [8] reporting a 5-year actuarial survival of 66%, both inclusive of operative mortality. Others have examined late survival rates for neonates and infants after surgical valvotomy reporting 10-year survival of 70% to 100% (exclusive of operative deaths), but with early deaths ranging from 36% to 59% [4, 7, 3].

Reintervention after surgical aortic valvotomy was predictably high in this study (13 of 33 survivors). Actuarial freedom from reintervention for hospital survivors was 68% at 5 years and 55% at 10 years, almost identical to those reported by Karl [6] and Gildein [8] and their colleagues. Perhaps surprisingly, more than 68% of hospital survivors are free of any adverse event (death, reintervention, endocarditis) at 5 years and about half are alive and free of any reintervention at 10 years (Fig 2). These numbers are remarkably similar to those reported by others including Messmer [5], Karl [6], Gildein [8], Elkins [21], and Kitchiner [7] and their colleagues. Like others, we also found that reintervention was largely for recurrent LV outflow tract obstruction and only rarely for severe aortic regurgitation [3, 8]. In most patients with little or no aortic insufficiency we have opted to proceed to balloon aortic valvuloplasty as the first reintervention. If the patient has moderate or severe aortic valve insufficiency or if there is a significant degree of subaortic stenosis, we have proceeded to surgical intervention. Over the years our surgical reintervention method has changed almost exclusively to the Ross or Ross/Konno procedure [21–23] rather than allograft or prosthetic valve insertion. We have found this to be most reliable, of relatively low risk, and perhaps the best long-term alternative for the growing infant or child who requires operative reintervention after a valvotomy in infancy.

This study was instituted specifically to examine our results so we could carefully examine the late results of surgical aortic valvotomy and make an educated decision regarding the institution of balloon aortic valvuloplasty as the procedure of choice for neonates and infants with critical AS. The 30-day procedure mortality for balloon aortic valvuloplasty has been reported to be in the range of 9.6% to 40%, but has reached low rates in recent years [13]. Although long-term results of balloon aortic valvuloplasty for older infants and children have been well described, late results for balloon valvuloplasty in neonates and young infants have been lacking. Bu’Lock and associates [24] demonstrated an intermediate survival of 50% at 3 years in a series of 14 infants less than 2 months of age at the time of balloon aortic valvuloplasty. In another large study of infants <30 days of age, Egito and associates [13] demonstrated survival of 63% a mean of 4.3 years after balloon valvuloplasty. When patients with a Rhodes score of 2 or greater were excluded from their series, survival improved to 88% at 8 years. In the large Valvuloplasty and Angioplasty of Congenital Anomalies study, age less than 3 months was a strong predictor of early and late mortality, but the actuarial results were not really delineated [12]. As in surgical series, LV hypoplasia and endocardial fibroelastosis appear to be important determinants of survival after balloon valvuloplasty [25]. It is difficult to compare directly the two modalities as the results of both operation and valvuloplasty are so affected by patient selection and favorable anatomy and it is often difficult to discern from an individual series how much patient selection is present [26].

Surgical valvotomy offers some advantages over both balloon aortic valvuloplasty and transventricular surgical valvuloplasty. Open aortic valvotomy offers the ability to inspect directly the valve and incise the commissures accurately and under controlled circumstances. It also offers the ability to resect dysplastic tissue or nodules, which we believe may contribute to a favorable long-term outcome by more completely relieving LV outflow tract obstruction. Indeed, a more extended aortic valvuloplasty has been reported to offer excellent results in some young infants [27] and our exact technique has been successfully used previously by others treating infants with critical AS [5, 6, 8]. Balloon valvuloplasty or transventricular valvotomy is a relatively uncontrolled situation where the tear may occur incompletely or even through one cusp, resulting in an unsatisfactory result with respect to residual LV outflow obstruction or aortic insufficiency [18].

In this study we had a relatively high rate of valve replacement with a prosthetic valve or Konno type reconstruction of the LV outflow tract. This reflects partially the time period and our own past preference for prosthetic valve insertion over allograft valve replacement. Certainly, since 1993, we have exclusively chosen pulmonary autograft insertion when aortic valve replacement is needed and the valve cannot be repaired or salvaged. In general, our approach to the first reintervention after aortic valvotomy is balloon aortic valvuloplasty if the reason for reintervention is primarily recurrent stenosis and aortic insufficiency is less than moderate. If balloon valvuloplasty fails we have then proceeded to pulmonary autograft insertion rather than repeat attempts at balloon valvuloplasty, as others have [13]. If the patient has moderate or greater aortic valve insufficiency we would proceed directly to a pulmonary autograft insertion. Although the long-term efficacy of pulmonary autograft insertion in infants is not proven, we consider it the best choice for aortic valve replacement in the growing child [21].

In summary, we consider aortic valvotomy still to be a valuable tool in the treatment of neonates and young infants with critical AS. The long-term results with respect to both survival and reintervention are good and compare favorably with other forms of neonatal congenital heart disease. We would consider surgical valvotomy the standard for comparison, despite the success of recent reports of balloon aortic valvuloplasty [13] and transventricular aortic valvotomy [2]. Neonates and young infants of small size or with evidence of severe endocardial fibroelastosis are not good candidates for surgical valvotomy and may be better candidates for conversion to a univentricular physiology or cardiac transplantation. Only with time, careful follow-up, and perhaps a randomized trial will we be able to determine accurately which therapy—surgical valvotomy, balloon aortic valvuloplasty, transventricular valvotomy, or even neonatal pulmonary autograft—is the best long-term solution to critical AS in the neonate and young infant.

	References

Top Abstract Introduction Patients and methods Results Comment References

 

1. Turley K., Bove E.L., Amato J.J., et al. Neonatal aortic stenosis. J Thorac Cardiovasc Surg 1990;99:679-684.[Abstract]
2. Mosca R.S., Iannettoni M.D., Schwartz S.M., et al. Critical aortic stenosis in the neonate. A comparison of balloon valvuloplasty and transventricular dilation. J Thorac Cardiovasc Surg 1995;109:147-154.[Abstract/Free Full Text]
3. Gaynor J.W., Bull C., Sullivan I.D., et al. Late outcome of survivors of intervention for neonatal aortic valve stenosis. Ann Thorac Surg 1995;60:122-126.[Abstract/Free Full Text]
4. Ettedgui J.A., Tallman-Eddy T., Neches W.H., et al. Long-term results of survivors of surgical valvotomy for severe aortic stenosis in early infancy. J Thorac Cardiovasc Surg 1992;104:1714-1720.[Abstract]
5. Messmer B.J., Hofstetter R., von Bernuth G. Surgery for critical congenital aortic stenosis during the first three months of life. Eur J Cardiothorac Surg 1991;5:378-382.[Abstract]
6. Karl T.R., Sano S., Brawn W.J., Mee R.B.B. Critical aortic stenosis in the first month of life: surgical results in 26 infants. Ann Thorac Surg 1990;50:105-109.[Abstract]
7. Kitchiner D., Sreeram N., Malaiya N., et al. Long-term follow-up of treated critical aortic stenosis. Cardiol Young 1995;5:9-14.
8. Gildein H.P., Kleinert S., Weintraub R.G., Wilkinson J.L., Karl T.R., Mee R.B.B. Surgical commissurotomy of the aortic valve: outcome of open valvotomy in neonates with critical aortic stenosis. Am Heart J 1996;131:754-759.[Medline]
9. Justo R.N., McCrindle B.W., Benson L.N., Williams W.G., Freedom R.M., Smallhorn J.F. Aortic valve regurgitation after surgical versus percutaneous balloon valvotomy for congenital aortic valve stenosis. Am J Cardiol 1996;77:1332-1338.[Medline]
10. Gatzoulis M.A., Rigby M.L., Shinebourne E.A., Redington A.N. Contemporary results of balloon valvuloplasty and surgical valvotomy for congenital aortic stenosis. Arch Dis Child 1995;73:66-69.[Abstract/Free Full Text]
11. Moore P., Egito E., Mowrey H., Perry S.B., Lock J.E., Keane J.F. Midterm results of balloon dilation of congenital aortic stenosis: predictors of success. J Am Coll Cardiol 1996;27:1257-1263.[Abstract]
12. McCrindle B.W. Independent predictors of immediate results of percutaneous balloon aortic valvotomy in childhood. Am J Cardiol 1996;77:286-293.[Medline]
13. Egito E.S.T., Moore P., O’Sullivan J., et al. Transvascular balloon dilation for neonatal critical aortic stenosis: early and midterm results. J Am Coll Cardiol 1997;29:442-447.[Abstract]
14. Rhodes L.A., Colan S.D., Perry S.B., Jonas R.A., Sanders S.P. Predictors of survival in neonates with critical aortic stenosis. Circulation 1991;84:2325-2335.[Abstract/Free Full Text]
15. Minich L.L., Tani L.Y., Hawkins J.A., McGough E.C., Shaddy R.E. Use of echocardiography for detecting aortic valve leaflet avulsion and predicting repair potential after balloon valvuloplasty. Am Jour Cardiol 1995;75:533-535.
16. Kaplan E.L., Meier P. Nonparametric estimation from incomplete observations. J Am Stat Assoc 1958;53:457-481.
17. Cox D.R. Regression model and life tables. J R Stat Soc 1972;B34:187-220.
18. Hawkins J.A., Minich L.L., Shaddy R.E., et al. Aortic valve repair and replacement after balloon aortic valvuloplasty in children. Ann Thorac Surg 1996;61:1355-1358.[Abstract/Free Full Text]
19. Gundry S.R., Behrendt D.M. Prognostic factors in valvotomy for critical aortic stenosis in infancy. J Thorac Cardiovasc Surg 1986;92:747-754.[Abstract]
20. Hammon J.W., Jr, Lupinetti F.M., Maples M.D., et al. Predictors of operative mortality in critical valvular aortic stenosis presenting in infancy. Ann Thorac Surg 1988;45:537-540.[Abstract]
21. Elkins R.C. Congenital aortic valve disease: evolving management. Ann Thorac Surg 1995;59:269-274.[Free Full Text]
22. Calhoon J.H., Bolton J.W.R. Ross/Konno procedure for critical aortic stenosis in infancy. Ann Thorac Surg 1995;60:S597-S599.
23. Reddy V.M., Rajasinghe H.A., Teitel D.F., Haas G.S., Hanley F.L. Aortoventriculoplasty with the pulmonary autograft: the Ross-Konno procedure. J Thorac Cardiovasc Surg 1996;111:158-167.[Abstract/Free Full Text]
24. Bu’Lock F.A., Joffe H.S., Jordan S.C., Martin R.P. Balloon dilatation (valvoplasty) as first line treatment for severe stenosis of the aortic valve in early infancy: medium term results and determinants of survival. Br Heart J 1993;70:546-553.[Abstract/Free Full Text]
25. Ladusans E.J., Parsons J.M., Qureshi S.A., Baker E.J., Tynan M.J. Results of percutaneous balloon dilation for critical aortic stenosis in neonates and with severe endocardial fibroelastosis [Abstract]. Br Heart J 1989;61:470.
26. Freedom R.M. Invited letter concerning: neonatal aortic stenosis. The balloon deflated?. J Thorac Cardiovasc Surg 1990;100:927.[Medline]
27. Ilbawi M.N., DeLeon S.Y., Wilson W.R., et al. Extended aortic valvuloplasty: a new approach for the management of congenital valvar aortic stenosis. Ann Thorac Surg 1991;52:663-668.[Abstract]

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This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): John A. Hawkins Lloyd Y. Tani Ronald W. Day Robert E. Shaddy Edwin C. McGough Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Hawkins, J. A. Articles by McGough, E. C. Search for Related Content PubMed PubMed Citation Articles by Hawkins, J. A. Articles by McGough, E. C.