| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Ann Thorac Surg 2007;84:574-580
© 2007 The Society of Thoracic Surgeons
a The Division of Pediatric Cardiac Surgery, Columbia University College of Physicians and Surgeons, New York, New York
b The Division of Pediatric Cardiology, Columbia University College of Physicians and Surgeons, New York, New York
Accepted for publication April 2, 2007.
* Address correspondence to Dr Hirata, The Division of Pediatric Cardiac Surgery, Columbia University College of Physicians and Surgeons, New York, NY 10032 (Email: yh2240{at}columbia.edu).
Presented at the Forty-third Annual Meeting of The Society of Thoracic Surgeons, San Diego, CA, January 29–31, 2007.
 |
Abstract |
|---|
 Top Abstract IntroductionPatients and MethodsResultsCommentDiscussionReferences |
|---|
Methods: The study cohort was composed of all patients presented with PAIVS from January 1999 through December 2005. Demographic and anatomic variables were analyzed to determine association with in-hospital mortality.
Results: Forty-four infants with PAIVS underwent catheter valvuloplasty (n = 17) and (or) surgical intervention (n = 42). The mean age and weight of the infants was six days and 3.1 kg, and the average follow-up was 40 ± 29.5 months. Five (11%) had right ventricle dependent coronary circulation (RVDCC) and six (14%) had Ebstein’s anomaly. Five (11%) patients died. Of those who underwent catheter valvotomy, three (18%) underwent shunt placement, 12 (71%) underwent right ventricular outflow tract reconstruction with shunt placement, and only two (12%) did not require a further surgical intervention in the newborn period. Multivariable analyses demonstrated RVDCC (odds ratio 21.3, p = 0.025) and Ebstein’s anomaly (odds ratio 16.0, p = 0.038) to be risk factors for in-hospital mortality. Of those patients with Ebstein’s anomaly, a single ventricle approach had a better outcome.
Conclusions: We demonstrated excellent recent outcomes for patients with PAIVS. Catheter-based interventions rarely avoid surgical repair. The RVDCC and Ebstein’s anomaly were associated with high mortality. In patients with Ebstein’s anomaly, single ventricular pathway may be the better strategy for this specific patient population.
|
Introduction |
|---|
|
TopAbstractIntroductionPatients and MethodsResultsCommentDiscussionReferences |
|---|
While several multiinstitutional studies [11–13] have delineated risk factors for survival and candidacy for repair, institutional variability may confound the application of these principles. We sought to delineate strategies for the optimal management of PAIVS by evaluating the following: (1) the effectiveness of the catheter pulmonary valvuloplasty in avoiding the need for surgery in the neonatal period; (2) the risk factors for in-hospital mortality; and (3) the characteristics predictive of those who fail biventricular strategies.
|
Patients and Methods |
|---|
|
TopAbstractIntroductionPatients and MethodsResultsCommentDiscussionReferences |
|---|
The following data were retrieved from the clinical records: demographic data including age, weight, complications, need for and type of subsequent additional interventions; for patients who died, the age at death and cause of death; and for survivors, their further management, follow-up duration, and outcomes.
The echocardiographic and angiographic recordings at presentation were reviewed to determine the morphology of the right ventricle, type of atresia (muscular versus membranous), tricuspid valve diameter, tricuspid valve Z value, degree of tricuspid regurgitation, and coronary artery abnormalities. The degree of tricuspid regurgitation was estimated as absent, mild, moderate, or severe on echocardiography. Furthermore, the presence of Ebstein’s malformation of the tricuspid valve was noted. The coronary artery anatomy was studied from the RV and aortic root angiograms and the presence of RV to coronary artery fistulae was noted. The RVDCC was defined by the presence of coronary arterial interruption, stenosis of one or more of the major epicardial arteries, or absent aortocoronary connection.
Statistical Analysis
Continuous variables were expressed as medians and ranges. Statistical methods were used to identify and estimate risk factors predicting the in-hospital mortality as well as failed biventricular strategy. Failed biventricular strategy was defined as the failure to achieve biventricular repair instead of attempted biventricular repair strategy. The univariate association between risk factors and postoperative outcome was assessed by using either the 
2 test for dichotomous risk factors or a t test for continuous risk factors. The Wilcoxon signed rank test was used to compare the changes in preoperative and postoperative tricuspid regurgitation. Logistic regression analysis of the in-hospital deaths was used to evaluate the risk factors in a multivariate manner.
|
Results |
|---|
|
TopAbstractIntroductionPatients and MethodsResultsCommentDiscussionReferences |
|---|
|
|
|
Survival
During the 40.0 ± 29.5 month follow-up period, six (13.6%) of 44 patients have died. There were five in-hospital deaths and one late death (Table 2). Probability of survival from the first intervention to one, three, and five years for all 44 patients was 89.1% (95% confidence interval [CI], 77.6% to 95.1%), 85.8% (95% CI, 72.0% to 93.5%), and 81.8% (95% CI, 65.0% to 91.6%), respectively (Fig 3). There were no deaths after the bidirectional Glenn (13) or Fontan (5) operations during the study period.
|
|
|
|
|
|
|
|
Comment |
|---|
|
TopAbstractIntroductionPatients and MethodsResultsCommentDiscussionReferences |
|---|
Our data demonstrate RV dependent coronary circulation and Ebstein’s anomaly to be risk factors for in-hospital mortality. In contrast to previous studies in which aberrations of coronary circulation were not shown to be specific risk factors for death [12, 14, 15], in our cohort RVDCC was related to postoperative LV dysfunction and death even in the absence of RV decompression. Additionally, one patient who was not diagnosed as having RVDCC died of severe LV dysfunction after RV decompression. Preoperative angiographic analysis demonstrated RV coronary fistulas without obvious coronary stenosis. While RV coronary fistula without coronary stenosis is not an accepted contraindication to RV decompression [5], our case indicates that it is sometimes difficult to predict the impact of these coronary anomalies.
In the subset of patients with Ebstein’s anomaly who underwent RV decompression, RV failure was the predominant cause of death. The combination of free pulmonary regurgitation and severe tricuspid regurgitation, working in concert with a noncompliant RV, can virtually eliminate forward flow from the right ventricle. Although some investigators have reported successful biventricular repair in this subpopulation [16, 17], we recommend tricuspid valve closure and univentricular strategy when the attempts at tricuspid valve repair fail.
Recent studies suggest that increasing numbers of patients are undergoing transcatheter pulmonary valvuloplasty for PAIVS and advocate this as the initial procedure [10, 18]. Others have advocated stenting of the ductus arteriosus as well as transcatheter pulmonary valvuloplasty [19]. We believe that these procedures are largely ineffective because they cannot adequately address the intricacies of this disease (pulmonary valve annular hypoplasia, subpulmonary obstruction, and RV noncompliance). Although pulmonary valvuloplasty can relieve obstruction caused primarily by abnormal pulmonary valve leaflets, it cannot enlarge the pulmonary valve annulus. Therefore, these patients with significant pulmonary valve annular obstruction will ultimately require surgical intervention. Indeed, we were not able to evaluate the growth potential of the pulmonary valve annulus in this cohort after catheter valvuloplasty because most of the patients required surgical intervention within the first month. Furthermore, catheter intervention cannot relieve subpulmonary muscular obstruction, a critical component of PAIVS. Although the creation of pulmonary insufficiency is often maligned, it is likely a primary factor responsible for the growth of these right ventricles after creation of a transannular patch. Lastly, while augmentation of pulmonary flow by stenting the ductus arteriosus may favorably alter the course of those patients with a relatively well-developed right ventricle [19], there is little reason to believe it will have any more impact than a modified BT shunt on those with a hypoplastic noncompliant RV when done in isolation. The efficacy of this approach however, requires further investigation.
Our data demonstrate that most patients whose tricuspid Z value is more than –3 without Ebstein’s anomaly can undergo a biventricular repair. Although Ebstein’s anomaly was a risk factor for in-hospital mortality, severe tricuspid regurgitation associated with a structurally normal valve was not. Our data suggest that tricuspid regurgitation without Ebstein’s anomaly is often due to the high RV pressure and tends to improve after RV decompression. In contrast, when associated with Ebstein’s anomaly, tricuspid regurgitation tended to persist after RVOT enlargement and often necessitates tricuspid valve closure and univentricular palliation.
In conclusion, we demonstrated excellent recent outcomes for patients with PAIVS. While catheter-based techniques were useful diagnostic modalities, rarely did balloon intervention avoid surgical repair. Ebstein’s anomaly and RVDCC were associated with high mortality. Patients with associated Ebstein’s anomaly may be better served by univentricular palliation.
|
Discussion |
|---|
|
TopAbstractIntroductionPatients and MethodsResultsCommentDiscussionReferences |
|---|
DR HIRATA: Yes, in select patients we are now attempting to put a stent in the ductus. It is our impression that it may prolong the time between the catheter intervention and the surgery. But, as I said before, this also cannot address the components of a pulmonary valve annular and infundibular hypoplasia, so we don’t think that this will supplant the RV outflow tract patch and shunt as an initial technique.
DR HENRY L. WALTERS (Detroit, MI): Congratulations on a great study. We have also experienced an increased mortality in patients who have true right ventricular dependent coronary circulation. I think, though, that I’m recalling it correctly when I say that the recent Boston series did not find this to be an independent risk factor for death. Our experience has been so dramatic that we’ve gone to transplantation in patients who have what appears to be unequivocal right ventricular dependent coronary circulation. I would be interested in your comments on that approach.
Finally, the postoperative course of all patients who have a transannular patch and a shunt, in this group of neonates, is not always smooth. We think that sometimes the postoperative course is complicated by the fact that there can be retrograde circus motion of flow through the shunt, then into the PA, then through the incompetent pulmonary valve, then into the RV, then retrograde through the tricuspid valve and through the ASD to the left side of the heart. Have you seen that phenomenon associated with a longer postop course with increased morbidity? Thank you.
DR HIRATA: Thank you. It’s a good question. As you stated, some authors have reported that RV dependent coronary circulation or fistula is not related to mortality. However, in our institution, RV dependent coronary circulation was a risk factor. And also we had one patient in the series who had non-RV dependent coronary circulation, but with epicardial stenosis and after decompression, the patient had severe left ventricular dysfunction. So we believe that there is some increased risk with many forms of coronary abnormalities.
In regards to the second question, we didn’t present the data, but it will appear in the manuscript. If the patient doesn’t have Ebstein’s anomaly, even if the patient has a preoperative severe tricuspid regurgitation, the majority of the tricuspid regurgitation will resolve after RV decompression.
In these circumstances, ie, preoperative TR associated with a morphologically normal tricuspid valve, we have not seen significant retrograde flow through the tricuspid valve. Patients with Ebsteinoid valves however, have persistent tricuspid regurgitation after RV decompression and likely retrograde flow into the right atrium.
DR HILLEL LAKS (Los Angeles, CA): I congratulate you on those excellent results. You didn’t mention if the transannular patches were done on bypass, and I wonder if you could describe that technique. And we have been using a transannular patch done without bypass and stratifying the patients into those who have mild hypoplasia with Z scores of zero to minus 2 and moderate hypoplasia minus 2 to minus 4, and severe hypoplasia lists at greater than minus 4, and in the severe group not addressing the outflow tract regardless of whether they have RV dependent or nondependent coronary circulations but only addressing them in the mild to the moderate group. And with that approach, we have seen no mortality difference between those three groups, excluding the Ebstein patients. So I wonder if you could comment on the technique that was used and whether any of the patients who had transannular patches fell into the severely hypoplastic group.
DR HIRATA: All of these transannular patches were performed using cardiopulmonary bypass. We incise the annulus onto the RV infundibulum and resect muscle in the infundibulum and place the Gore-Tex patch as the transannular patch. The decision to perform a transannular patch depends upon the surgeon’s impression of the RV size, the tricuspid valve Z score, and the presence or absence of coronary abnormalities.
DR LAKS: I think that what one is trying to achieve with a transannular patch or a valvuloplasty is to get antegrade flow so that you just get emptying of the right ventricle. If you have an ASD (atrial septal defect) and you have wide open pulmonary valve regurgitation, which you do when you get an on-pump big resection, and you then add a BT (Blalock-Taussig) shunt, which they almost always need because they don’t get good enough antegrade flow unless they have only very mild hypoplasia, you then have a high RV end diastolic pressure and very little forward flow into this right ventricle. And those patients end up with tricuspid valves that don’t develop and a RV which gets quite big. So the advantage of an off-pump procedure is to just open it up enough to get some antegrade flow and some emptying of the RV but not enough that you get wide open regurgitation from your shunt. And I think that that combination works out better than having a big outflow patch and then having a shunt added to that and then having a high end diastolic pressure and very little forward flow.
The other thing is that when you do have coronary dependent circulation or even extensive sinusoids, it’s very important to make the BT shunt as small as possible so you don’t get the volume overload and the diastolic drop in coronary perfusion pressure, which happens with a large shunt, and that tends to make it more stable. Thank you.
DR HIRATA: This has not been our experience. We find it safer and more efficacious to perform the outflow patch and resection on CPB (coronary pulmonary bypass). This allows good visualization of the main PA (pulmonary artery) and RV (right ventricle) infundibulum. Operating on the RV outflow tract and main PA, especially in a neonate, with a full and beating heart limits visibility and places the LAD (left anterior descending coronary artery) in jeopardy. In our experience, the right ventricles in these patients are very noncompliant; thus, there is modest retrograde flow from the shunt into the RV cavity at the conclusion of the procedure. In addition, we believe that the RV cavity has the best chance of "growing" if an adequate resection is performed that allows both forward flow and perhaps a bit of pulmonary insufficiency as well.
DR SHUNJI SANO (Okayama, Japan): Your conclusion is almost similar to us. We presented a paper at the Thirty-Sixth Annual Meeting of the STS in Fort Lauderdale. The difference from ours is as follows: our initial approach includes a modified BT shunt and a pulmonary valvotomy through the left chest. Another difference is that pediatric cardiologist check the patients few months after the initial operation and they do balloon dilate if necessary to decompress the RV. The point is that RV should be gradually decompressed if the patient has RV-coronary sinusoid formation. If the patient has a sinusoid formation, RV decompression is only a little, to keep the RV/LV pressure ratio between 1.0 and 0.8.
In some patients, the RV-coronary sinusoid formation disappears gradually if it is minor, but if it is major, it doesn’t disappear. If the patient’s sinusoid formation disappears, then we do a biventricular repair. If the sinusoid formation does not disappear, then we do a single ventricular repair. In case of pulmonary atresia with Ebstein’s, most of the patients are going to the single ventricular repair with excision of RV free wall.
DR HIRATA: Thank you, Dr. Sano. We would proceed with RV decompression in the presence of a fistula if there is no evidence of severe epicardial stenosis or RV dependency. We have not had experience with your technique of gradual decompression of the right ventricle. Thank you.
|
References |
|---|
|
TopAbstractIntroductionPatients and MethodsResultsCommentDiscussionReferences |
|---|
This article has been cited by other articles:
|
|
 |
|
  M Marasini, P F Gorrieri, G Tuo, L Zannini, P Guido, M Pellegrini, S Bondanza, M G Calevo, and G Pongiglione Long-term results of catheter-based treatment of pulmonary atresia and intact ventricular septum Heart, September 15, 2009; 95(18): 1520 - 1524. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Krasemann Radiofrequency perforation: the optimum treatment for pulmonary atresia? Heart, September 15, 2009; 95(18): 1473 - 1474. [Full Text] [PDF]
|
|
|
|
 |
|
 R. L. Hannan, J. A. Zabinsky, R. M. Stanfill, R. A. Ventura, A. F. Rossi, D. G. Nykanen, E. M. Zahn, and R. P. Burke Midterm Results for Collaborative Treatment of Pulmonary Atresia With Intact Ventricular Septum Ann. Thorac. Surg., April 1, 2009; 87(4): 1227 - 1233. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |
= pulmonary atresia with intact ventricular septum [PAIVS]; 
= PAIVS-Ebstein.)