Results of surgical treatment of coarctation of the aorta in the critically ill neonate

Preoperative Physiology, Imaging, and Management of Coarctation of Aorta in Children

Coarctation of the aorta (CoA) is a narrowing of the proximal thoracic aorta typically located at the junction of the aorta with the ductus arteriosus. While it is a simple lesion to understand, considerable variation exists in the anatomy and pathophysiology, leading to varied clinical presentation, management options, and prognosis. On the one hand critical CoA manifests in the neonatal period as a duct-dependent lesion, while less severe forms of obstruction present later in childhood or adulthood as hypertension or incidentally noted precordial murmurs. While transthoracic echocardiography is usually adequate, older children and adults may need more advanced imaging modalities like computed tomography and magnetic resonance imaging prior to intervention. Depending on the type of lesion, management options currently available include surgery and percutaneous balloon angioplasty and stenting. Even after successful interventions, these patients need life-long surveillance for residual aortic obstruction and systemic hypertension with variable long-term clinical outcomes.

Mortality of pulmonary artery banding in the current era: recent mortality of PA banding

BACKGROUND

The mortality of pulmonary artery banding improved significantly in the 1980s. However, we lack information on this procedure in the current era.

METHODS

The results of pulmonary artery banding in 365 patients who had operations between 1966 and 2001 were reviewed. The patients were divided into three groups: (1) group 1 patients who had operations between 1966 and 1979, (2) group 2 patients who had operations between 1980 and 1989, and (3) group 3 patients who had operations between 1990 and 2001.

RESULTS

Significantly younger and smaller patients have been operated on recently (mean age: group 1, 169.0 +/- 40 days; group 2, 101.8 +/- 11 days; and group 3, 69.7 +/- 8.9 days; and mean weight: 4.6 +/- 0.1, 4.1 +/- 0.1, and 3.2 +/- 0.1 kg, respectively). A decrease was found in the number of simple cardiac anomalies, such as isolated ventricular septal defects. The early mortality in the three groups was 38.3% for group 1 (65 of 187), 13.5% for group 2 (15 of 111), and 13.8% for group 3 (12 of 87). Although the mortality did not vary significantly between groups 2 and 3, it improved over time in patients weighing less than 3 kg. Multivariate analysis of group 3 demonstrated that no isolated variable, including sex, weight, and diagnosis was a significant risk factor.

CONCLUSIONS

Despite the advances in perioperative management, we found no improvement in the early mortality of pulmonary artery banding during the last decade. These results will support the preference for primary repair of intracardiac anomalies in small infants. However, this operation can now be performed with the same risk even in smaller patients. We believe that pulmonary artery banding has a role in the treatment of congenital cardiac anomalies.

Decision making for the surgical management of aortic coarctation associated with ventricular septal defect

Coarctation of the aorta and associated ventricular septal defect may be repaired simultaneously or by initial coarctation repair with or without banding of the pulmonary artery. The question is whether specific preoperative criteria can enable the surgeon to choose the optimal surgical management. Between 1980 and 1993, 80 infants younger than 3 months with coarctation and ventricular septal defect were treated surgically. In 64 infants (multistage group), simple coarctation repair was performed through a posterolateral approach, with concomitant banding of the pulmonary artery in 10 infants. Twenty ventricular septal defects were closed as a secondary procedure and four were closed as a tertiary procedure. Sixteen infants (single-stage group) underwent one-stage repair through an anterior midline approach. The total in-hospital mortality rate was 7.5%. Freedom from recoarctation after 5 years was 91.3% in the multistage group versus 60.0% in the single-stage group (p = 0.018). Freedom from secondary ventricular septal defect treatment in the multistage group after 5 years was 40.7%, versus 100% in the single-stage group (p = 0.016). Thirty-seven ventricular septal defects (47.8%) closed spontaneously. In particular, the preoperative left-to-right shunt and extension of the perimembranous VSD into the inlet or outlet were risk factors for the need for eventual surgical ventricular septal defect closure after initial coarctation repair. On the basis of these two risk factors, the probability of the need for eventual surgical treatment of ventricular septal defect after initial coarctation repair can be calculated. This policy offers a well-considered choice between single-stage and multistage repair, weighing the risk of secondary ventricular septal defect treatment versus the risk of recoarctation. Finally, the number of surgical procedures per infant will be as low as possible.

Repair of coarctation of the aorta in neonates and infants: a thirty-year experience

Between January 1962 and December 1991, 179 children less than 1 year of age underwent repair of coarctation of the aorta. Group I (1962 to 1971) consisted of 19 patients, group II (1972 to 1981) of 57 patients, group III (1982 to 1991) of 103 patients. Neonates (< 30 days old) made up 60% of group I, 57% of group II, and 70% of group III. The proportion of infants with associated complex cardiac abnormalities was 7% in group I, 25% in group II, and 39% in group III. Techniques of repair included resection with end-to-end anastomosis (n = 65), subclavian flap repair (n = 85), patch aortoplasty (n = 18), and other procedures (n = 11). The early mortality (< 30 days) was lowest in group III (group I, 21%; group II, 21%; and group III, 7%; p < 0.05), but the late mortality was similar in all groups (group I, 11%; group II, 13%; and group III, 15%). The overall actuarial survival was 57.7% +/- 0.15% at 27.1 years in group I, 65.7% +/- 0.07% at 19.7 years in group II, and 77.5% +/- 0.04% at 9.3 years in group III (p = not significant). Twenty-five restenoses requiring intervention occurred in 23 patients, for an overall restenosis rate of 16.4%. The incidence of restenosis was 23% for the patients who underwent end-to-end anastomosis, 11% for those who underwent subclavian flap repair (p < 0.1), and 27% for those who underwent patch aortoplasty (p < 0.01). Balloon angioplasty was successful in relieving 11 of the 12 restenoses in groups II and III.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia for Cardiac Surgery in Newborns with Congenital Heart Disease

The repair of complex congenital heart disease in the neonatal period is an evolving practice that began a decade ago and has resulted in improved survival and reduced long term morbidity. Surgical techniques and anesthetic, management hare evolved to care for these uniquely challenging infants. Optimal anesthetic care requires a sound basis in normal and pathologic neonatal and dedopmental physiology, cardiac and pediatric anesthesia, and cardiopulmonary bypass management. Typical concerns in neonatal congenital heart patients include a reduced myocardial compliance and poorly

developed calcium transport systems. This limits stroke volume and increases calcium requirements in the post-bypass patient. Additionally, abnormal blood flow patterns are common and may be adversely affected by inotropes, inspired oxygen concentration, carbon dioxide tension, and mechanical ventilation. The impact of cardiopulmonary bypass on the neonate is extreme. Infants are commonly cooled to 15°C, their blood volume is hemodiluted by 3-4 fold, and periods of total circulatory arrest for up to 60 min are routine. The physiologic impact of these biologic extremes on organ function must be anticipated. Bypass management must assure optimal distribution of pump flow to minimize any impediment to organ protection. High dose narcotics combined with a benzodiazepine have become an integral part of anesthetic management for the neonate with congenital heart disease. Combined intravenous drug therapy provides a complete anesthetic (sedation amnesia and analgesia), hemodgnamic stability, reduced stress hormone release, and control of pulmonary vascular reactivity. Thii reduces the need for multiple inotropic therapy aimed at decreasing pulmonary vascular resistance and improving myocardial contractility. This manuscript provides an in-depth understanding of the anesthetic management of the neonate with complex congenital heart disease. The overall goal of anesthetic management is to deliver a patient to the ICU with stable hemodynamics and a clear management plan based on intraoperative observations and interventions.

Follow-up results of balloon angioplasty of native coarctation in neonates and infants

The purpose of this study is to present intermediate-term results of balloon angioplasty of native aortic coarctation in neonates and infants less than 1 year of age. During a 60-month-period that ended in January 1990, 19 infants ages 3 days to 12 months (median, 2.5 months), underwent balloon angioplasty of native coarctation with resultant reduction in peak-to-peak systolic pressure gradient from 39 +/- 12 mm Hg (mean +/- SD) to 11 +/- 7 mm Hg (p less than 0.001) and increase in coarctation segment size from 2.2 +/- 0.8 mm to 4.7 +/- 1.0 mm. None required immediate surgical intervention. Thirteen of the 19 (68%) had severe associated cardiac defects. There was one death (5%) 2 days after balloon angioplasty, and it was related to associated cardiac defect. One infant was lost to follow-up. It is too soon to restudy one infant. The remaining 16 infants had clinical (36 +/- 18 months) and catheterization (12 +/- 4 months) follow-up data. The residual coarctation gradient (22 +/- 15 mm Hg) and coarcted segment size (4.4 +/- 1.6 mm) remain improved (p less than 0.01) when compared with pre-balloon angioplasty values. Five of the 16 (31%) infants (four were neonates at the time of balloon angioplasty) had evidence for recoarctation (defined as gradient greater than 20 mm Hg) and underwent surgical resection (two) or repeat balloon angioplasty (three), all with success. None developed aneurysms.(ABSTRACT TRUNCATED AT 250 WORDS)

Feasibility of reversible pulmonary artery banding: early results and intermediate-term follow-up

Development of a reversible pulmonary artery band might obviate the need for a second cardiac surgical procedure in children with some forms of congenital heart disease. We evaluated a segmented Silastic-coated Dacron mesh band 2 to 4 mm wide sewn together with absorbable 2-0 polydioxanone suture for use as a reversible pulmonary artery band. Nine puppies 6 to 8 weeks old (mean weight, 5.8 kg) underwent placement of this pulmonary artery band. All survived the operation with a mean initial systolic gradient of 6.5 +/- 1.6 mm Hg and underwent cardiac catheterization at monthly intervals for 3 months. Two puppies died of right ventricular failure. The remaining puppies underwent balloon angioplasty with balloons 20 to 25 mm in diameter. No complications resulted from balloon angioplasty, but 1 puppy died 24 hours later of unidentified causes. Balloon angioplasty decreased the mean gradient from 46.7 +/- 6.8 mm Hg to 6.7 +/- 2.6 mm Hg. Angiography showed an increase in mean diameter of the site of the pulmonary artery band from 5.2 +/- 1.0 to 10.8 +/- 1.7 mm Hg. There was no evidence of vessel injury on angiograms. Fourteen months after balloon angioplasty, the mean gradient was 22.3 +/- 17.0 mm Hg. Our data demonstrate that a functionally reversible pulmonary artery band constructed of segmented Silastic-coated Dacron mesh and 2-0 polydioxanone suture is feasible.

Remodeling of the aorta after successful balloon coarctation angioplasty

The purpose of this study was to examine whether remodeling of the aorta takes place after successful balloon angioplasty of aortic coarctation. During the 35 month period ending in December 1987, 30 children, aged 14 days to 13 years, underwent balloon angioplasty of unoperated aortic coarctation, with a resultant reduction in mean coarctation gradient from 44 +/- 20 to 10 +/- 8 mm Hg (p less than 0.001). On the basis of results of 6 to 30 months' follow-up catheterization data in 20 children, the patients were classified into group A (13 patients with good results; gradient less than or equal to 20 mm Hg and no recoarctation on angiography) and group B (7 patients with fair or poor results; gradient greater than 20 mm Hg with or without recoarctation on angiography). Measurements of the aorta at five sites (the ascending aorta, isthmus, coarcted segment and descending aorta distal to the coarctation and at the level of the diaphragm) were made in two angiographic views, corrected for magnification and averaged. A standardized diameter of the aorta at the five locations was calculated for each case before angioplasty and at follow-up study, and variance of the diameter was then determined. The variance of standardized aortic measures (0.233 versus 0.287) was similar (p greater than 0.05) in both groups before angioplasty, whereas at follow-up study (0.057 versus 0.129) they were different (p = 0.01). There was a greater percent improvement at follow-up study (0.233 versus 0.057) in the group with good results than in the group with fair or poor results (0.287 versus 0.129).(ABSTRACT TRUNCATED AT 250 WORDS)

Balloon angioplasty of aortic coarctation: a review

Since the initial report of balloon coarctation angioplasty in 1982, several workers used this technique in native coarctation and postoperative recoarctation. Immediate and intermediate-term follow-up results are generally good with a small chance for recoarctation and aneurysmal formation at the site of coarctation. The causes of recoarctation were identified and include age less than 1 year, isthmus hypoplasia, and a small coarcted aortic segment. Despite good immediate and follow-up results, recommendations for use of balloon angioplasty as a treatment procedure of choice are clouded by the reports of development of aneurysms at the site of coarctation. We feel that balloon coarctation angioplasty is the treatment of choice in neonates and small infants, while general use of this technique in both native and postoperative coarctations in older children should await follow-up results in larger numbers of children at selected centers.

Pulmonary artery banding: analysis of a 25-year experience

A 25-year experience (May 1962 through April 1987) with pulmonary artery banding in 183 patients was reviewed and analyzed. Pulmonary artery banding was performed in a heterogeneous group of patients aged two days to 60 months (median, 10 weeks; mean, 21.8 weeks) and weighing 1.4 to 13.8 kg (mean, 4.2 kg). Diagnosis was ventricular septal defect in 76 (41.5%) and atrioventricular communis in 41 (22.4%). Pulmonary artery banding was also used in patients with d-transposition of the great vessels with ventricular septal defect, double-outlet right ventricle, univentricular heart, tricuspid atresia, and truncus arteriosus. Early death occurred in 39 of 175 patients who underwent pulmonary artery banding at Ochsner Foundation Hospital (22.3%). Definitive operation has been performed in 37 of the patients who underwent pulmonary artery banding since 1979 with excellent outcome in 32 (86.5%). Pulmonary artery banding is a useful palliative procedure for a diverse group of patients with congenital cardiac anomalies and unrestricted pulmonary blood flow. With improved results of primary repair of intracardiac anomalies in small infants, however, pulmonary artery banding should be reserved for severely ill patients with complex lesions not amenable to early definitive correction. Currently, pulmonary artery banding is indicated in patients with excessive pulmonary blood flow and single ventricle or tricuspid atresia. Pulmonary artery banding is also appropriate in certain patients with atrioventricular communis and in patients with muscular or multiple ventricular septal defects. Pulmonary artery banding is an option in patients with ventricular septal defect and coarctation of the aorta.

Causes of recoarctation after balloon angioplasty of unoperated aortic coarctation

During the 35 month period ending December 1987, 30 children, aged 14 days to 13 years, underwent balloon angioplasty of unoperated aortic coarctation with resultant reduction in coarctation gradient from 43.6 +/- 20.4 to 9.5 +/- 7.6 mm Hg (p less than 0.001). None of the patients required immediate surgical intervention. On the basis of results of 6 to 30 month follow-up catheterization data in 20 children, the patients were classified as follows: Group A, 13 patients with good results (gradient less than or equal to 20 mm Hg and no recoarctation on angiograms) and Group B, 7 patients with fair or poor results (gradient greater than 21 mm Hg with or without recoarctation on angiography). No patient developed aortic aneurysm at the site of angioplasty. Thirty variables were examined by multivariate logistic regression analysis and four factors were identified as risk factors for development of recoarctation: 1) age less than 12 months, 2) aortic isthmus less than 2/3 the size of the ascending aorta immediately proximal to the right innominate artery, 3) coarcted aortic segment less than 3.5 mm before dilation, and 4) coarcted aortic segment less than 6 mm after angioplasty. The identification of risk factors may help in selection of patients for balloon angioplasty. Avoiding or minimizing the number of risk factors may help reduce the chance of recoarctation after angioplasty. The intermediate-term follow-up results with regard to recoarctation are comparable with those after surgical repair of coarctation. Recoarctation after angioplasty was dealt with by repeat balloon angioplasty or surgical resection for those requiring treatment and clinical follow-up for the remaining children.(ABSTRACT TRUNCATED AT 250 WORDS)

Balloon angioplasty for coarctation of the aorta: immediate and long-term results

Twenty-five infants and children with native coarctation of the aorta had percutaneous balloon angioplasty over a 28-month period ending in May, 1987. The mean systolic pressure gradient across the coarctation decreased from 47.6 +/- 20.9 mm Hg to 10.3 +/- 7.3 mm Hg (p less than 0.001) following angioplasty, and the diameter of the coarcted segment increased from 3.2 +/- 1.7 mm to 7.8 +/- 3.5 mm (p less than 0.001). Clinical and echo-Doppler follow-up indicated excellent results in 16 of the 18 patients in whom 3- to 22-month follow-up was available; two infants required additional treatment (repeat angioplasty in one and surgical resection in the other). Fourteen patients who underwent repeat cardiac catheterization remain improved with regard to pressure gradient across the dilated coarctation (9.5 +/- 9.6 mm Hg, p less than 0.001) and angiographically measured sizes of the coarcted segment (10.3 +/- 3.2 mm, p less than 0.001). No aneurysm was seen in any child. We recommend balloon angioplasty as the therapeutic procedure of choice for relief of severe, previously unoperated coarctation of the aorta in neonates and young infants. Routine use of balloon angioplasty for unoperated coarctation of the aorta in children appears indicated, but should await longer follow-up results and reports of follow-up on a larger number of patients; this caution is mainly based on reports from other workers of aneurysm formation at the site of balloon dilatation.

Pulmonary artery banding: results and current indications in pediatric cardiac surgery

The results of pulmonary artery banding in 144 patients seen from 1971 to 1984 were reviewed. Age ranged from 1 week to 4 years (median, 8 weeks) and weight, from 1.1 to 16 kg (median, 4 kg). The patients were divided into three major groups: Group 1, defects without mixing disorders (ventricular septal defect, double-outlet right ventricle [DORV], atrioventricular septal defect); Group 2, defects with mixing disorders (transposition of the great arteries, DORV, single ventricle, tricuspid atresia); and Group 3, miscellaneous (mitral atresia, left ventricular hypoplasia, truncus complex). The diagnostic group influenced survival (p = 0.0035). In Group 1, 88.8% survived, but only 64.9% survived in Groups 2 and 3 combined. The presence of patent ductus arteriosus or coarctation of the aorta had no effect on survival (p = 0.61 and p = 0.7, respectively). The clinical condition at thirty days after pulmonary artery banding was good in 35.1% and fair in 46.9% of the patients. When the data were divided into the three periods 1971 through 1974, 1975 through 1979, and 1980 through 1984, which included 28, 49, and 67 patients, respectively, a significant improvement in survival was observed from the early (64.3%) to the late period (92.5%) (p = 0.0009). Patients weighing less than 4 kg had a significantly lower survival in the period 1971 through 1974 (37.5% versus 91.67%). No significant difference in survival was detected in the late period, 1980 to 1984 (90% versus 94.6%), between patients weighing less than and those weighing more than 4 kg. Pulmonary artery banding is clinically satisfactory in small infants and children with complex anomalies.

Indications and techniques for midline approach to aortic coarctation in infants and children

A variety of techniques have been described for the repair of aortic coarctation. Most of these use operative exposure through a left thoracotomy. There are, however, instances when a median sternotomy provides a more versatile approach and allows for equally acceptable repair. Twelve patients (age, 2 days to 16 years) with coarctation of the aorta serve to illustrate the value of the technique. All but 3 patients were under 3 years old. Five patients had repair of coarctation combined with repair of other congenital cardiac anomalies (atrial and ventricular septal defects, 2 patients; atrial septal defects, 2 patients; and valvular aortic stenosis, 1 patient). Six patients had complicated recurrences of previously repaired coarctations and 1 patient had a primary coarctation that involved the aortic arch. All repairs were accomplished through a median sternotomy with the use of cardiopulmonary bypass and periods of (1) total circulatory arrest (6 patients); (2) reduced flow (4 patients); or (3) normal flow with multiple sites of arterial inflow (2 patients). All patients did well with no operative mortalities and no sequelae to date (8 weeks to 4 years). Examples of various techniques are provided to demonstrate the flexibility obtainable with this method. Median sternotomy can provide a viable approach to difficult problems involving coarctation of the aorta.

Neonatal surgery for coarctation of the aorta. The Gothenburg experience

Thirty-four neonates (weights 0.97-4.47 kg) were operated on for coarctation of the aorta. They included five premature infants with birth weight less than or equal to 2.1 kg. All 34 were symptomatic, 31 severely so. Coarctation was "simple" in 12 cases and "complex" in 22; 12 with ventricular septal defect and 10 with more complex malformations. The mean age at operation was 11 days. Subclavian flap aortoplasty was used in 27 cases, a lusoric artery in two, and combined end-to-end anastomosis and flap repair in five. The main pulmonary artery was banded in 13 of the 22 complex coarctation syndromes. Absorbable suture was used in the last 22 cases. There was one early postoperative death. Serious ischaemic complications (bowel or limb gangrene) arose in four patients who were in severe heart failure preoperatively. During follow-up averaging 1.9 years there were two recurrences of coarctation. Resection with end-to-end anastomosis combined with subclavian flap aortoplasty when there is bulging ductal tissue or long, narrow isthmus and use of absorbable vascular suture may further lower the incidence of recurrent coarctation.