Unifocalization for pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries

Single-stage Unifocalization and Intra-cardiac Repair using Two Tube Grafts

Unifocalization of the major aorto-pulmonary collaterals (MAPCAs) followed by intra-cardiac repair with ventricular septal defect (VSD) closure and restoration of right ventricle to pulmonary artery (RV-PA) continuity is the ultimate treatment goal in a case of VSD with pulmonary atresia (PA) and MAPCAs. It may be achieved in a single stage or may require multiple surgeries. We present a case of a 2 year old boy with VSD/PA who underwent single stage unifocalization of MAPCAs through midline followed by intra-cardiac repair using two polytetrafluoroethylene (PTFE) tube grafts; one for unifocalization and other as a bicuspid valved RV-PA conduit.

Comparison of computed tomography angiography versus cardiac catheterization for preoperative evaluation of major aortopulmonary collateral arteries in pulmonary atresia with ventricular septal defect

Introduction:

Pulmonary atresia with the ventricular septal defect is a rare congenital heart defect with high anatomic variability. The most important management question relates to the sources of pulmonary blood flow. The ability to differentiate between ductal dependence and major aortopulmonary collateral arteries is critical to achieving good outcomes and avoiding life-threatening hypoxia in the postneonatal period. Having accurate information about pulmonary arteries, major aortopulmonary collateral arteries, and sources of blood supply to each pulmonary segment is crucial for choosing the optimal surgical strategy. The purpose of this study is to compare computed tomography angiography (CTA) with cardiac catheterization for anatomic delineation of surgically relevant anatomy in pulmonary atresia with ventricular septal defect with major aortopulmonary collateral arteries.

Materials and Methods:

Retrospective review of all children with pulmonary atresia with ventricular septal defect with major aortopulmonary collateral arteries cared for at a large tertiary children's hospital who underwent cardiac catheterization with angiography and CTA close to each other without interval therapy. All studies were performed between 2007 and 2011.

Results:

There were 9 patients who met the inclusion criteria. Pulmonary artery anatomy (confluent vs. nonconfluent) was correctly identified in 9 patients by CTA and 8 patients by catheterization. There were no significant differences between CTA and catheterization in the identification of major aortopulmonary collateral arteries (mean = 3.4 collaterals/study via catheterization; mean = 3.1 collaterals/study via CTA; P = 0.67). CTA was superior to catheterization in the delineation of segmental pulmonary blood flow (P = 0.006).

Conclusion:

CTA and catheterization are equivalent in their ability to delineate pulmonary artery anatomy and major aortopulmonary collateral arteries.

Mid-Term Outcome of Right Ventricle to Pulmonary Artery Shunt for Older Children and Young Adults With Ventricular Septal Defect, Pulmonary Atresia, and Hypoplastic Pulmonary Arteries

Management strategy for patients of ventricular septal defect and pulmonary atresia (VSD/PA) with hypoplastic pulmonary arteries presenting in late childhood or adolescence is still controversial. We present our experience with the use of right ventricle-pulmonary artery shunt (RV-PA) in management of this entity. Between January 2014 and April 2018, 25 patients of VSD/PA underwent valveless RV-PA shunt at our center. The size of the RV to PA shunt was calculated as half the expected diameter of the main pulmonary artery. We retrospectively reviewed the data from hospital records. Follow-up data were recorded from outpatient records or via telephone. Mean age of the cohort was 12.25 ± 3.18 years. There was 1 early and 1 interstage mortality. None of the patient developed acute renal failure, ventricular dysfunction, and arrhythmias. At interstage follow-up of 8.28 ± 3.7 months, both Nakata index (from 66.23 ± 24.12 to 185.8 ± 58 mm²/m²) and McGoon ratio (0.9 ± 0.22 vs 49 1.84 ± 0.4) increased significantly compared to preoperative value, whereas RPA-LPA ratio was not significantly changed (1.095 ± 0.39 vs 1.01 ± 0.56, P = 0.63). Prerepair pulmonary vascular resistance in 17 patients, who underwent complete repair, was 2.9 ± 0.69 woods unit/m². Postrepair right ventricle-left ventricle pressure ratio was 0.5 ± 0.14. There was no early or late mortality and none of the patient required conduit revision or VSD fenestration. On follow-up of 25.75 ± 17.94 months, 16 patients were in NYHA I and 1 patient was in NYHA II. Appropriate-sized RV-PA shunt is an effective strategy for achieving balanced pulmonary artery growth in VSD/PA with hypoplastic pulmonary arteries presenting late without the risk of pulmonary over circulation or systemic malperfusion.

Repair of Untreated Older Patients With Tetralogy of Fallot With Major Aortopulmonary Collaterals

BACKGROUND

Our programmatic approach to tetralogy of Fallot with major aortopulmonary collaterals emphasizes single-stage unifocalization with complete intracardiac repair during infancy. Little is known about suitability for complete repair in patients beyond infancy. We sought to analyze outcomes of our approach in older patients with previously untreated tetralogy of Fallot with major aortopulmonary collaterals.

METHODS

Any patient with this lesion not treated before 2 years of age referred to our center from 2002 to 2017 met inclusion criteria.

RESULTS

Of 33 patients, 32 were out-of-state (64% international) referrals, and 33% (n = 11) were older than 9 years, had polycythemia, or at least 1 high pressure collateral (>25 mm Hg). Complete repair was achieved in 94% (n = 31) of patients, 82% (n = 27) in one stage and 12% (n = 4) after unifocalization to a central shunt. The median right ventricular-to-aortic pressure ratio was 0.31 after the operation and 0.37 at follow-up. At a median of 4.8 years after repair, 9 patients (19%) underwent reintervention, including 5 conduit and 7 branch pulmonary artery interventions. Three patients also underwent aortic valve replacement.

CONCLUSIONS

In this selected cohort of older patients with previously unoperated tetralogy of Fallot with major aortopulmonary collaterals, outcomes were comparable with infants undergoing treatment according to our approach. These findings support the notion that patients who are either born in low-resource settings or present to health care providers beyond infancy should be considered candidates and evaluated for complete repair.

Outcomes of Patients with Pulmonary Atresia and Major Aortopulmonary Collaterals Without Intervention in Infancy

Treatment of pulmonary atresia with major aortopulmonary collaterals (PA MAPCAs) remains a challenge. Despite variations in surgical technique, contemporary strategies all include initial intervention in the first year of life. However, a subset of patients presents later in life, and contemporary outcomes of this group have not been reported previously. We performed a retrospective case series of consecutive cases of PA MAPCAs who were seen at our center between January 2001 and February 2016, who had not undergone surgery before the age of 1 year. We describe their presenting characteristics, operative and transcatheter interventions, and outcomes. A total of eight cases were identified from 76 children with PA MAPCAs treated over the study period. Median age at presentation was 5.9 years. Seventy-five percent had confluent pulmonary arteries with a median Nakata index of 113 mm(2)/m(2). Operative intervention was performed in 5/6 cases. Two are awaiting intervention. The combination of operative and transcatheter interventions allowed for ventricular septal defect closure in 60 % of cases, all of whom had subsystemic right ventricular pressures. Operative intervention is possible in some older cases with PA and MAPCAs. Though multiple operations and transcatheter therapies are necessary, some can achieve operative correction of serial circulation with tolerable physiology. Subjects with ventricular hypoplasia and those without confluent pulmonary arteries are more challenging.

Consensus on timing of intervention for common congenital heart diseases: part II - cyanotic heart defects

The purpose of this review/editorial is to discuss how and when to treat the most common cyanotic congenital heart defects (CHDs); the discussion of acyanotic heart defects was presented in a previous editorial. By and large, the indications and timing of intervention are decided by the severity of the lesion. While some patients with acyanotic CHD may not require surgical or transcatheter intervention because of spontaneous resolution of the defect or mildness of the defect, the majority of cyanotic CHD will require intervention, mostly surgical. Total surgical correction is the treatment of choice for tetralogy of Fallot patients although some patients may need to be palliated initially by performing a modified Blalock-Taussig shunt. For transposition of the great arteries, arterial switch (Jatene) procedure is the treatment of choice, although Rastelli procedure is required for patients who have associated ventricular septal defect (VSD) and pulmonary stenosis (PS). Some of these babies may require Prostaglandin E1 infusion and/or balloon atrial septostomy prior to corrective surgery. In tricuspid atresia patients, most babies require palliation at presentation either with a modified Blalock-Taussig shunt or pulmonary artery banding followed later by staged Fontan (bidirectional Glenn followed later by extracardiac conduit Fontan conversion usually with fenestration). Truncus arteriosus babies are treated by closure of VSD along with right ventricle to pulmonary artery conduit; palliative banding of the pulmonary artery is no longer recommended. Total anomalous pulmonary venous connection babies require anastomosis of the common pulmonary vein with the left atrium at presentation. Other defects should also be addressed by staged correction or complete repair depending upon the anatomy/physiology. Feasibility, safety and effectiveness of treatment of cyanotic CHD with currently available medical, transcatheter and surgical methods are well established and should be performed at an appropriate age in order to prevent damage to cardiovascular structures.

Individualized approach to the surgical treatment of tetralogy of Fallot with pulmonary atresia

BACKGROUND

Tetralogy of Fallot with pulmonary atresia is a heterogeneous group of defects, characterised by diverse sources of flow of blood to the lungs, which often include multiple systemic-to-pulmonary collateral arteries. Controversy surrounds the optimal method to achieve a biventricular repair with the fewest operations while basing flow to the lungs on the native intrapericardial pulmonary arterial circulation whenever possible. We describe an individualized approach to this group of patients that optimizes these variables.

METHODS

Over a consecutive 10-year period, we treated 66 patients presenting with tetralogy of Fallot and pulmonary atresia according to the source of the pulmonary arterial flow. Patients were grouped according to whether the flow of blood to the lungs was derived exclusively from the intrapericardial pulmonary arteries, as seen in 29 patients, exclusively from systemic-to-pulmonary collateral arteries, as in 5 patients, or from both the intrapericardial pulmonary and collateral arteries, as in the remaining 32 patients. We divided the latter group into 9 patients deemed simple, and 23 considered complex, according to whether the pulmonary arterial index was greater than or less than 90 millimetres squared per metre squared, and whether the number of collateral arteries was less than or greater than 2, respectively.

RESULTS

We achieved complete biventricular repair in 58 patients (88%), with an overall mortality of 3%. Repair was accomplished in a single stage in all patients without systemic-to-pulmonary collateral arteries, but was staged, with unifocalization, in the patients lacking intrapericardial pulmonary arteries. Complete repair without unifocalization was achieved in all patients with the simple variant of the mixed morphology, and in 56% of patients with the complex variant. The average number of procedures per patient to achieve complete repair was 1, 2.2, 3.8, and 2.6 in patients with exclusively native intrapericardial, simple and mixed, complex and mixed and exclusively collateral pulmonary arterial flow, respectively.

CONCLUSIONS

An individualized approach based on the morphology of the pulmonary arterial supply permits achievement of a high rate of complete intracardiac repairs, basing pulmonary arterial flow on the intrapericardial pulmonary arteries in the great majority of cases, and has a low rate of reoperation and mortality.

Pulmonary atresia with ventricular septal defects and major aortopulmonary collateral arteries

BACKGROUND

There is no consensus on the long-term outcome after unifocalization in patients undergoing surgery for pulmonary atresia with ventricular septal defects (VSD) and major aortopulmonary collateral arteries (MAPCAs).

METHODS AND RESULTS

From 1988 to 2006, 40 patients (median age 8.5 months) underwent surgery for pulmonary atresia, VSD, and MAPCAs. The hospital mortality rate for the preparatory procedures was 1.2%; 17 patients had a complete repair (CR) at a median age of 3 years. Patients with a pulmonary artery index greater than 100 mm(2)/m(2) had a higher likelihood of CR. The overall survival rate 15 years after first operation in the CR group was 87.5%. Cox analysis demonstrated that increased number of MAPCAs (P=0.019, HR=1.666) was a significant predictor of poor survival, and CR (P=0.025, HR=0.141) was a significant predictor of favorable prognosis. On angiography, serial measurements of MAPCAs showed a significant decrease in size (from 5.2+/-2.9 to 4.1+/-2.9 mm after a mean of 20 months) (P<0.0001).

CONCLUSIONS

Long-term survival into adulthood can be achieved with an integrated approach. Late survival depends on the number of MAPCAs, and CR. Growth potential of unifocalized MAPCAs was not definite.

Cardiac defects and results of cardiac surgery in 22q11.2 deletion syndrome

Specific types and subtypes of cardiac defects have been described in children with 22q11.2 deletion syndrome as well as in other genetic syndromes. The conotruncal heart defects occurring in patients with 22q11.2 deletion syndrome include tetralogy of Fallot, pulmonary atresia with ventricular septal defect, truncus arteriosus, interrupted aortic arch, isolated anomalies of the aortic arch, and ventricular septal defect. These conotruncal heart defects are frequently associated in this syndrome with additional cardiovascular anomalies of the aortic arch, pulmonary arteries, infundibular septum, and semilunar valves complicating cardiac anatomy and surgical treatment. In this review we describe the surgical anatomy, the operative treatment, and the prognostic results of the cardiac defects associated with 22q11.2 deletion syndrome. According to the current literature, in patients with tetralogy of Fallot with/without pulmonary atresia and truncus arteriosus, in spite of the complex cardiac anatomy, the presence of 22q11.2 deletion syndrome does not worsen the surgical prognosis. On the contrary in children with pulmonary atresia with ventricular septal defect and probably in those with interrupted aortic arch the association with 22q11.2 deletion syndrome is probably a risk factor for the operative treatment. The complex cardiovascular anatomy in association with depressed immunological status, pulmonary vascular reactivity, neonatal hypocalcemia, bronchomalacia and broncospasm, laryngeal web, and tendency to airway bleeding must be considered at the time of diagnosis and surgical procedure. Specific diagnostic, surgical, and perioperative protocols should be applied in order to provide appropriate treatment and to reduce surgical mortality and morbidity.

A case with heterotaxy reaching the Fontan procedure after unifocalizations

One patient with major aorto-pulmonary collateral arteries and heterotaxy underwent staged unifocalizations, and eventually the staged Fontan completion. Subsequent to the bidirectional Glenn procedure, the left pulmonary artery was once thrombozed, but successfully treated. The progressively regurgitant common atrioventricular valve needed repair twice during the course. Pulmonary arterial pressure was 11 mm Hg 1 year after the Fontan procedure.

Clinical results of staged repair with complete unifocalization for pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries

OBJECTIVE

Our treatment strategy for pulmonary atresia with ventricular septal defect (VSD) and major aortopulmonary collateral arteries is a staged repair that comprises the first complete unifocalization (UF) with 'unification' of intrapulmonary arteries and then the definitive repair. The purpose of this study is to evaluate the outcome of our staged repair strategy with complete UF and to determine the results of our current management strategy.

METHODS

From 1982 to 2004, 113 consecutive patients were treated with staged repair at our institute. We evaluated the risk of definitive repair failure or death in the 3 years after definitive repair using logistic regression. Furthermore, we compared the early group (patients who underwent UF before December 1995) and the late group (patients who underwent UF after January 1996).

RESULTS

The mean follow-up interval was 8.8 years (0.8 months to 23.3 years), and Kaplan-Meier-estimated overall survival rates after first UF were 80.9, 73.8, and 69.9% at 5, 10, and 15 years, respectively. Survival in patients with an absent central pulmonary artery (PA) was significantly lower than in those with a central PA (p<0.05), and the factor that was significantly associated with definitive repair failure or death in the 3 years after definitive repair was central PA morphology (p<0.05). Higher mean PA pressure after UF was detected in patients with hypoplastic central PA, compared with those without hypoplastic PA (30.9 mmHg vs 23.3 mmHg, p<0.05). In the late group, age (in years) at first UF (3.9 vs 8.4, p<0.01), second UF (4.3 vs 9.2, p<0.01), and definitive repair (5.8 vs 9.1, p<0.01) was significantly younger than in early group, and the survival rate after first UF in the late group was 96.2 and 91.3% at 3 and 7 years, respectively. Systolic right ventricular pressure and the pressure ratio between the right and the left ventricles after definitive repair in the late group were significantly lower than in the early group (53.6 mmHg vs 75.0 mmHg, p<0.01; 61.7% vs 75.9%, p<0.05).

CONCLUSIONS

Hypoplastic central PA was a significant risk factor in this disease. The overall survival was improved by our current management strategy. Improved RV pressure after definitive repair appears to affect the long-term outcome.

Biventricular repair for right atrial isomerism

BACKGROUND

Biventricular repair is often difficult to accomplish in patients with right atrial isomerism because of complex anomalous structures.

METHODS

Ten patients with right atrial isomerism underwent biventricular repair. Their ages ranged from 15 months to 21 years. The follow-up period ranged from 1 month to 21 years. The Fontan procedure was unsuitable in 7 patients. The atrioventricular valves were separated in 5 patients and common in 5. One patient who had severe right-sided atrioventricular valvular regurgitation required concomitant prosthetic valve replacement. Another patient with a hypoplastic intraventricular septum underwent ventricular septation. Nine patients had two balanced ventricles. A ventricular septal defect was enlarged for rerouting in 3 patients. All patients had anomalous venoatrial connections and required intra-atrial baffle rerouting. One with major aortopulmonary collateral arteries underwent staged unifocalization. Three had extracardiac conduit repair. The outcomes were compared with 97 patients who underwent the Fontan procedure.

RESULTS

There were 3 early deaths and 1 late death. Six survivors are in New York Heart Association functional class I or II. Two are free from medications. Two required reoperation owing to infection or prosthetic valve failure. At 1 year, cardiac index and systemic venous pressure were 3.2 +/- 0.9 L.min(-1).m(-2) and 6.6 +/- 1.6 mm Hg, respectively. There were no significant differences in survival, freedom from arrhythmia, freedom from reoperation, or exercise tolerance between biventricular repair and the Fontan procedure.

CONCLUSIONS

Biventricular repair provided good long-term outcomes in patients with right atrial isomerism. In selected circumstances, biventricular repair is an acceptable alternative to the Fontan procedure.

Independent factors associated with mortality, reintervention, and achievement of complete repair in children with pulmonary atresia with ventricular septal defect

OBJECTIVES

We described morphologic characteristics, particularly pulmonary anatomy, and determined the prevalence of definitive end states and their determinants in children with pulmonary atresia associated with ventricular septal defect (PAVSD).

BACKGROUND

Pulmonary atresia associated with ventricular septal defect represents a broad morphologic spectrum that greatly influences management and outcomes.

METHODS

From 1975 to 2004, 220 children with PAVSD presented to our institution. Blinded angiographic review (n = 171) characterized bronchopulmonary segment arterial supply.

RESULTS

A total of 185 patients underwent surgery, and repair was definitive in 75%. Initial operations included systemic-pulmonary artery shunt in 57%, complete primary repair in 31%, or right ventricular outflow tract reconstruction in 12%. Based on angiographic review, 118 patients had simple PAVSD and 53 patients had PAVSD with major aortopulmonary collateral arteries (MAPCAs). Overall survival from initial operation was 71% at 10 years. Risk factors for death after initial operation included younger age at repair, earlier birth cohort, fewer bronchopulmonary segments supplied by native pulmonary arteries, and initial placement of a systemic-pulmonary artery shunt. Competing-risks analysis for initially palliated patients predicted that after 10 years, 68% achieved complete repair (with associated factors including later birth cohort and more bronchopulmonary segments supplied by native pulmonary arteries), 22% died without repair, and 10% remained alive without repair. Reoperations after complete repair occurred in 38 children (27%), with risk factors including older age at palliation, MAPCAs, and more segments supplied by collaterals.

CONCLUSIONS

Outcomes in children with PAVSD have improved over time, and are better in completely repaired cases. Bronchopulmonary arterial supply is an important determinant of mortality, achievement of definitive repair, and post-repair reoperation.

Intermediate Results of the Double-Switch Operations for Atrioventricular Discordance

BACKGROUND

Since 1987, anatomic biventricular repair using the double-switch operations has been our principal choice for patients with atrioventricular discordance. These alternative procedures have the theoretical advantage of using the anatomic left ventricle to support the systemic circulation.

METHODS

A total of 45 patients underwent the double-switch operation. Their ages ranged from 6 months to 21 years. Associated malformations included pulmonary atresia in 27, pulmonary stenosis in 11, and Ebstein's malformation in 5. An atrial switch plus an arterial switch procedure was performed in 7, and an atrial switch plus a Rastelli-type ventriculoarterial switch procedure in 38. Follow-up ranged from 6 months to 15 years.

RESULTS

Early mortality was 8.9% (n = 4). In the latter half of the series (n = 23, since 1994), there was no early death. Six patients died late. Actuarial survival at 5 and 10 years was 83.6% and 77.6%, respectively. Six patients required conduit replacement, and 2 required revision of an intraatrial baffle for pulmonary venous channel obstruction and infection, respectively. Freedom from reoperation was 95.3% at 5 years and 76.2% at 10 years. Freedom from arrhythmia was 88.8% at 5 years and 78.4% at 10 years. The systemic ventricular ejection fraction was 0.568 +/- 0.103 at 1 year (n = 39), 0.555 +/- 0.105 at 5 years (n = 17), and 0.539 +/- 0.098 at 10 years (n = 12).

CONCLUSIONS

The surgical results of the double-switch operations have been improving. Intermediate follow-up suggests that these alternative procedures are a reasonable option for patients with atrioventricular discordance.

Pulmonary atresia with ventricular septal defects and major aortopulmonary collateral arteries: Unifocalization brings no long-term benefits

OBJECTIVES

We sought to evaluate the contribution of unifocalization procedures in the management of patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries.

METHODS

From 1975 through 1995, 82 consecutive patients were entered in a multistage approach and had 189 sternotomies and thoracotomies to perform 119 shunts, 130 major aortopulmonary collateral artery transplantations, and 76 major aortopulmonary collateral artery ligations. The serial angiographies and the follow-up of these patients were reviewed.

RESULTS

The concurrent follow-up rate was 80%. The hospital mortality of the preliminary procedures was 4% (7/189). Fifty-three (65%) patients had a complete repair. The hospital mortality of the repair was 8% (4/53), and 9 late deaths occurred after repair, all of which were cardiac related. The overall survival of all patients to the age of 30 years was 58% +/- 7%. Survival 12 years after complete repair was 51% +/- 14%. On angiography, central shunts promoted growth of central pulmonary arteries in all cases (29 patients). Sixty unifocalized major aortopulmonary collateral arteries were identified in 31 patients. After a mean of 3.2 +/- 4 years, 26 thrombosed, and 12 presented with a stenosis of greater than 50%. Serial measurements of 29 major aortopulmonary collateral arteries showed no signs of growth (P = .25).

CONCLUSION

Long-term survival into adulthood of patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries has been achieved with a multistage approach. However, late survival depends exclusively on the growth of the native pulmonary circulation. The few unifocalized major aortopulmonary collateral arteries that did not thrombose failed to grow.

The effect of gene transfer with hepatocyte growth factor for pulmonary vascular hypoplasia in neonatal porcine model

BACKGROUND

Severe degree of pulmonary vascular hypoplasia remains a major limitation in congenital heart surgery. Considering the potential effect of gene transfer with hepatocyte growth factor to induce the angiogenesis in the lung, we assessed the effects of hepatocyte growth factor gene transfer in neonatal porcine lung with pulmonary vascular hypoplasia to achieve treatment for severe pulmonary vascular hypoplasia.

METHODS

The model of pulmonary vascular hypoplasia was introduced with left pulmonary artery banding in piglet lung. After 7 days of pulmonary artery banding, piglets were transfected selectively to the left lung via the left pulmonary artery with a hemagglutinating virus of Japan E vector bearing the cDNA encoding human hepatocyte growth factor (H group) or control vector (C group).

RESULTS

Seven days after the transfection, selective angiography of the left pulmonary artery showed the progression of left pulmonary vascular hypoplasia of the left lung in the C group but a significant attenuation of left pulmonary vascular hypoplasia in the H group. A right pulmonary artery occlusion test showed a marked increase in right ventricular systolic pressure in the C group, but this was significantly attenuated in the H group (C: 22.0 +/- 2.9, H: 13.0 +/- 2.7 mm Hg; P < .05). Histologic examination revealed that hepatocyte growth factor gene transfection increased the pulmonary vasculature in the left lung.

CONCLUSIONS

Our results demonstrated that gene transfer of hepatocyte growth factor via the pulmonary artery showed the angiogenic effects in porcine model of pulmonary vascular hypoplasia after pulmonary artery banding.

Primary repair of pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals: a useful approach

BACKGROUND

The ultimate goal of surgical therapy for pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries is to create unobstructed and separate in series pulmonary and systemic circuits. Our preference has been a 1-stage complete unifocalization technique, avoiding collateral anastomosis with either the native pulmonary arteries or other aortopulmonary collateral vessels.

METHODS AND RESULTS

Since 1998, 5 patients (median age 29.6 months) with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries have undergone surgical correction, consisting of (1) exclusion of a descending thoracic aortic segment from which all major aortopulmonary collateral arteries originate, and (2) connection of this aortic segment to the native pulmonary artery using an interposition polytetrafluoroethylene conduit. The ventricular septal defect was closed in all patients, and the right ventricle was connected to the unifocalized pulmonary artery with a valved conduit. All patients survived the operation. Two patients required reexploration for postoperative bleeding. One patient remained on mechanical ventilation for 17 days due to a pulmonary infection. During follow-up (12-21 months), no patient required additional interventions. The postoperative right ventricular/left ventricular pressure ratio was 0.55 median. No significant stenosis within the reconstructed pulmonary circuit was identified. All patients remain free of symptoms, requiring no medications.

CONCLUSION

Intracardiac repair of pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries can be accomplished by a midline 1-stage repair including complete unifocalization of all pulmonary blood supply without individual collateral anastomosis in selected patients. This approach offers a convenient and satisfactory surgical option.

Staged repair of pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries: Experience with 104 patients

OBJECTIVE

To determine the early and intermediate-term outcome of the staged repair used to treat children with pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries.

METHODS

We reviewed a retrospective case series of 104 patients with this complex lesion. Information was obtained from medical records and referring physicians.

RESULTS

Of the 104 patients treated with the staged repair, 58 achieved completion of anatomic repair. The 10-year mortality was 16.5%. In the patients with complete repair, the median right-to-left ventricle pressure ratio was 0.5. The overall surgical reoperation rate was 17%, and 15.5% of patients required postoperative interventional cardiac catheterization. In the multivariate analysis, the number of collateral vessels incorporated in the repair was found to be an independent risk factor for postoperative mortality and an elevated right-to-left ventricle pressure ratio after complete repair.

CONCLUSION

The staged repair can be successfully used to treat patients with pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries. This method yields a relatively low mortality with good functional results.

Use of small stents for rehabilitation of hypoplastic pulmonary arteries in pulmonary atresia with ventricular septal defect

Branch pulmonary artery stenosis frequently occurs in pulmonary atresia with ventricular septal defect (PA/VSD). Balloon dilation alone is often unsuccessful in patients with severely hypoplastic pulmonary arteries with residual stenoses after surgical repair. In an attempt to promote distal pulmonary artery growth, 17 stents were placed in 12 severely stenotic pulmonary artery lesions in 10 patients with PA/VSD. All had prior surgery, including pulmonary artery repair, right ventricle to pulmonary artery homograft, and, in 6 of 10, closure of VSD. Median age at stent placement was 16.8 months (range, 13.2-56). Stents were placed using 3.0, 3.5, or 4.0 mm balloons in all but one lesion, in which a 7 mm balloon was used. Following stent placement, there was an increase in the lesion diameter from 1.5 to 3.4 mm (P < 0.05) and an increase in flow to the affected lung from 27% to 34% (P < 0.05). Repeat catheterization 2 to 6 months after stenting in six patients revealed complete occlusion in two of eight lesions. In the other six vessels, there was an increase in distal vessel diameter from 2.96 to 3.94 mm (P < 0.05) even though four had severe restenosis requiring restenting. Two patients underwent surgical pulmonary artery reconstruction and stent removal because of adequate distal vessel growth. Stenting of hypoplastic pulmonary arteries in PA/VSD results in immediate improvement in vessel size and blood flow. Stent restenosis is common although distal vessel growth can be achieved. Stenting of these lesions should be reserved only for those patients unresponsive to other interventions.

Staged unifocalization and anatomic repair in a patient with right isomerism

Anatomic biventricular repair was successfully achieved subsequent to bilateral unifocalizations of the pulmonary blood supply using heterologous pericardial rolls in a patient with isomeric right appendages and major aortopulmonary collateral arteries.

External compression of bronchus by aneurysm from divided major aortopulmonary collateral artery after unifocalization

The right ventricle to pulmonary artery connection with an extracardiac conduit, left pulmonary artery reconstruction, ligation of patent ductus arteriosus, and take-down of right Blalock--Taussig shunt were performed on a 1-year-8-month-old boy who had pulmonary atresia, ventricular septal defect, patent ductus arteriosus, and major aortopulmonary collateral arteries. He previously underwent the unifocalization and right modified Blalock--Taussig shunt at 9 months of age. He repeatedly had a difficulty in weaning from the mechanical ventilator. After removing the aneurysm from the divided major aortopulmonary collateral artery that compressed the left main bronchus externally, it was possible to wean him from the mechanical ventilator.

Ventilatory response to exercise in patients with major aortopulmonary collateral arteries after definitive surgery

Patients with pulmonary atresia and major aortopulmonary collateral arteries (MAPCAs) may be at risk for both ventilatory impairment and abnormal pulmonary circulation after definitive surgery. We measured the ventilatory response to exercise in 16 patients with MAPCAs after definitive surgery (group A) and compared the results with those in 16 patients with tetralogy of Fallot with pulmonary atresia and without MAPCAs after definitive operation (group B), with 24 patients with tetralogy of Fallot after one-stage repair without previous palliation (group C), and with 48 healthy subjects (group D). Pulmonary function and treadmill exercise tests were performed. Arterial blood gases were also analyzed and the dead space to tidal volume ratio calculated. In group A, the vital capacity, diffusion capacity, and peak oxygen uptake were lowest (p <0.001), whereas the ventilatory equivalent for carbon dioxide was highest and its value at peak exercise correlated with age at time of surgery (r = 0.73, p <0.002). The arterial oxygen tension decreased progressively in group A and its value at peak exercise inversely correlated with the mean pulmonary artery pressure in all patients (r = -0.75, p <0.001). The arterial carbon dioxide tension decreased significantly at peak exercise in controls but showed no change in group A. The dead space to tidal volume ratio decreased during exercise in patients without MAPCAs and in controls but increased in group A, and the dead space to tidal volume ratio at peak exercise was inversely correlated with vital capacity in all patients (r = -0.77, p <0.001). Diffusion capacity independently predicted arterial carbon dioxide tension and dead space ventilation during exercise. Marked restrictive ventilatory impairment with low diffusion capacity along with a pulmonary obstructive change contributed to the abnormal pulmonary gas exchange during exercise in group A. Earlier repair of MAPCAs may prevent the progression of the impaired ventilatory response to exercise in these patients.

Early and intermediate outcomes after repair of pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries: experience with 85 patients

BACKGROUND

Pulmonary atresia with ventricular septal defect (VSD) and major aortopulmonary collaterals (MAPCAs) is a complex lesion with marked heterogeneity of pulmonary blood supply. Traditional management has involved staged unifocalization of pulmonary blood supply. Our approach has been to perform early 1-stage complete unifocalization in almost all patients.

METHODS AND RESULTS

Since 1992, 85 patients with pulmonary atresia, VSD, and MAPCAs have undergone unifocalization (median age, 7 months). Complete 1-stage unifocalization and intracardiac repair were performed through a midline approach in 56 patients, whereas 23 underwent unifocalization in a single stage with the VSD left open, and 6 underwent staged unifocalization through sequential thoracotomies. There were 9 early deaths. During follow-up (1 to 69 months), there were 7 late deaths. Actuarial survival was 80% at 3 years. Among early survivors, actuarial survival with complete repair was 88% at 2 years. Reintervention on the neo-pulmonary arteries was performed in 24 patients.

CONCLUSIONS

Early 1-stage complete unifocalization can be performed in >90% of patients with pulmonary atresia and MAPCAs, even those with absent true pulmonary arteries, and yields good functional results. Complete repair during the same operation is achieved in two thirds of patients. There remains room for improvement; actuarial survival 3 years after surgery is 80%, and there is a significant rate of reintervention. These results must be appreciated within the context of the natural history of this lesion: 65% of patients survive to 1 year of age and slightly >50% survive to 2 years even with surgical intervention.

Congenital Heart Surgery Nomenclature and Database Project: pulmonary atresia--ventricular septal defect

Pulmonary atresia (PA) and ventricular septal defect (VSD) is a complex and extremely heterogeneous cardiopulmonary malformation that has not been accurately defined, as evidenced by the synonymous use of the term with tetralogy of Fallot with PA. The anatomy and morphology of the pulmonary circulation to a large extent determines the surgical approach and overall outcome, with the intracardiac anatomy playing a secondary role. Based on the characterization of the pulmonary circulation a new classification of PA-VSD is proposed. In type A, there are only native pulmonary arteries (NPA). In type B, pulmonary blood flow is provided by both NPA and by major aortopulmonary collateral arteries [MAPCA(s)]. In type C, there are only MAPCA(s) and no NPA. This new classification is proposed for the purpose of establishing a unified reporting system. The subject was debated and reviewed by members of the STS-Congenital Heart Surgery Database Committee and representatives from the European Association for Cardiothoracic Surgery. All efforts were made to include all relevant nomenclature categories using synonyms where appropriate. A comprehensive database set is presented which is based on a hierarchical scheme. Data are entered at various levels of complexity and detail which can be determined by the clinician. These data can lay the foundation for comprehensive risk stratification analyses. A minimum database set is also presented which will allow for data sharing and would lend itself to basic interpretation of trends. Outcome tables relating diagnoses, procedures, and various risk factors are presented.

Total repair of pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals: an integrated approach

OBJECTIVE

Predicting postrepair right ventricular/left ventricular pressure ratio has prognostic relevance for patients undergoing total repair of pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries. To this purpose, we currently rely on 2 novel parameters: (1) preoperative total neopulmonary arterial index and (2) mean pulmonary artery pressure changes during an intraoperative flow study.

METHODS

Since January 1994, 15 consecutive patients (aged 64 +/- 54 months) with pulmonary atresia, ventricular septal defect, and major aortopulmonary collaterals were managed according to total neopulmonary arterial index. Seven patients with hypoplastic pulmonary arteries and a total neopulmonary arterial index less than 150 mm(2)/m(2) underwent palliative right ventricular outflow tract reconstruction followed by secondary 1-stage unifocalization and ventricular septal defect closure. The other 8 patients with a preoperative index of more than 150 mm(2)/m(2) underwent primary single-stage unifocalization and repair. The ventricular septal defect was closed in all cases (reopened in 1). In 9, such decision was based on an intraoperative flow study.

RESULTS

Patients treated by right ventricular outflow tract reconstruction had a significant increase of pulmonary artery index (P=.006) within 22 +/- 6 months. Repair was successful in 14 cases (postrepair right ventricular/left ventricular pressure ratio = 0.47 +/- 0.1). One hospital death occurred as a result of pulmonary vascular obstructive disease, despite a reassuring intraoperative flow study. Accuracy of this test in predicting the postrepair mean pulmonary artery pressure was 89% (95% CI: 51%-99%). At follow-up (18 +/- 12 months), all patients are free of symptoms, requiring no medications.

CONCLUSIONS

The integrated approach to total repair of pulmonary atresia, ventricular septal defect, and major aortopulmonary collaterals by preoperative calculation of total neopulmonary arterial index, right ventricular outflow tract reconstruction (when required), and intraoperative flow study may lead to optimal intermediate results.

Pediatric cardiac surgery in the 1990s

Future developments in the repair of these complex anomalies will rely heavily on a complete understanding of present results, which can be achieved only with attention to detail and rigorous standards. Results must be continually updated and management changes carefully planned and then critically examined for significant differences. Thus, the day-to-day care of patients with congenital heart disease must withstand careful scrutiny, both for consistency and for end results.

Heparin as a risk factor for perigraft seroma complicating the modified Blalock-Taussig shunt

OBJECTIVE

The purpose of this study was to determine the risk factors associated with the occurrence of perigraft seromas complicating systemic-to-pulmonary polytetrafluoroethylene grafts.

METHODS

Clinical and perioperative variables were reexamined, blinded for the outcome variable perigraft seroma, in 60 patients undergoing 67 consecutive graft procedures in a 3.5-year period.

RESULTS

Eight cases of perigraft seroma were diagnosed in six patients. Univariate analysis revealed age (p = 0.02), a diagnosis of pulmonary atresia with ventricular septal defect and systemic-pulmonary collaterals (p = 0.001), reimplantation of collaterals during the procedure (p < 0.001), and intravenous heparin administered after operation (p < 0.0001) as risk factors for symptomatic perigraft seroma. Multivariable analysis defined heparin as the only significant factor associated with symptomatic perigraft seroma. Consolidation of the upper lobe on chest radiograph, ipsilateral to the shunt, directly after operation (p = 0.01), but especially 8 to 10 days after operation (p < 0.0001), or the need for prolonged drainage of pleural fluid (p < 0.0001) were correlated with the occurrence of perigraft seroma. Perigraft seroma led to four early rethoracotomies in three patients and to accelerated corrective surgery in three cases. Consolidation and absent perfusion of lung segments persisted in two patients.

CONCLUSIONS

Our data suggest that the use of heparin leads to an increased risk of perigraft seroma, complicating systemic-pulmonary polytetrafluoroethylene grafts. Prolonged pleural drainage and/or postoperative consolidation of the upper lobe indicate the development of symptomatic perigraft seroma. Treatment is controversial and results are unpredictable. Expectative management seems to be justified so long as permitted by the clinical condition.

One-stage midline unifocalization and complete repair in infancy versus multiple-stage unifocalization followed by repair for complex heart disease with major aortopulmonary collaterals

BACKGROUND

Patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries have traditionally required multiple unifocalization staging operations before undergoing complete repair. Recently, the feasibility of a single-stage unifocalization and repair was demonstrated by Hanley. In this report, we describe our experience with each approach.

METHODS AND RESULTS

Since 1989, 11 of 12 patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries have undergone complete surgical correction. The first seven patients were subjected to staged bilateral unifocalizations, with repair being achieved in six (group I). The last five patients have undergone a single-stage midline unifocalization and repair via a sternotomy (group II). Four of these were infants (2 weeks to 9 months) and one was 13 years old. All patients in group I had tetralogy of Fallot, whereas in group II three patients had tetralogy of Fallot, one patient had double-outlet right ventricle, and one patient had complete atrioventricular canal and transposition. In group I, the median age at the first operation was 43 weeks. Complete repair was performed at a median age of 3.5 years, with a mean number of 3.3 operations required. In group II, only one operation was required to achieve complete repair at a median age of 28 weeks. The postoperative right ventricular/left ventricular pressure ratio was 0.49 in group I and 0.45 in group II. One intraoperative death and one late death occurred in group I and no early or late deaths in group II. Currently, four patients in group I and all five patients in group II are alive and well.

CONCLUSIONS

Early intervention with both surgical approaches can lead to complete biventricular repair in most patients. Because the single-stage midline unifocalization and repair can achieve a completely repaired heart in infancy with one operation, it is currently our approach of choice.

Pulmonary circulation after biventricular repair in patients with major systemic-to-pulmonary collateral arteries

OBJECTIVE

To determine factors affecting postoperative pulmonary circulation in patients with major systemic-to-pulmonary collateral arteries.

METHODS

A total of 48 patients underwent biventricular repair subsequent to unifocalization at ages in the range 1-34 years. The preparative procedures consisted of ligation of the collateral arteries in 6, plasty to the pulmonary arteries using no artificial materials in 12 and extensive reconstruction using heterologous pericardial tubes in 30. The number of the pulmonary vascular segments unifocalized was 9-18 (16 +/- 3). The amount of flow draining via residual minute systemic-to-pulmonary collaterals measured at the time of repair was 4-58% (24 +/- 16%) of the total perfusion by the cardiopulmonary bypass machine.

RESULTS

This value was 40 +/- 16% in 5 patients dying in the short term after repair. The number of segments was nine or ten after unifocalization in 2 of these. Another 4 patients died in the longer term, 3 of these with CATCH 22 syndrome dying because of pulmonary hypertension. Postoperative catheterization demonstrated mean pulmonary arterial pressures in the range 8-40 (21 +/- 9) mmHg and pulmonary resistance in the range 1.7-10 (5.0 +/- 2.1) units/m2. Pulmonary resistance was correlated statistically to age at repair (r = 0.77), the number of pulmonary vascular segments (r = -0.41) and to percent collateral flow (r = 0.48). The use of a heterologous pericardial tube for unifocalization was also related probably to higher pulmonary resistance.

CONCLUSION

It is essential to accomplish effective unifocalizations followed by earlier definitive repair so as to establish better pulmonary circulation.