Intraatrial Baffle Procedure Research Articles

Abstract 15542: Late Pulmonary Hypertension in Surgically Palliated D-transposition of the Great Arteries: A 55-year Review

Introduction: Pulmonary hypertension (PH) has been described following surgical palliation for transposition of the great arteries (D-TGA). While early pulmonary vascular disease is associated with late repair, the increasing prevalence of late PH has been observed following the intra-atrial baffle procedure (ABP), Mustard/Senning. A previous study from our institution identified patients with precapillary PH. More recent studies have described predominately postcapillary PH, suggesting multiple, differing mechanisms for this complication. Hypothesis: While heart failure is a common complication following ABP and is associated with postcapillary PH, we hypothesize that precapillary PH can be identified in a subset of patients. Methods: A retrospective descriptive study was performed at a single institution. Using 6 th World Symposium on Pulmonary Hypertension definitions. PH was defined as a mean pulmonary artery pressure >20mmHg. Etiology of PH was defined as precapillary (≥3 Wood units) versus postcapillary (pulmonary artery wedge pressure >15 mmHg). Results: We reviewed 157 D-TGA patients following ABP, finding 33 patients with PH. Mean age at last evaluation was 36.6 (14-54) years. Current condition: 22 alive, 7 dead, and 4 lost to follow-up. Etiology of PH: 10 precapillary, 8 postcapillary, 8 mixed, 2 borderline PH, and 2 did not undergo catherization. Additionally, 2 patients had pulmonary venous baffle obstruction and 1 had left lung hypoplasia. Of patients with recent imaging, 21 of 25 had systemic RV systolic dysfunction on echocardiogram or MRI. Conclusions: Late-onset PH in D-TGA following ABP is a significant long-term complication and warrants vigilant surveillance. This highlights the limitations of imaging and need for catheterization for complete evaluation. In this study, we observed precapillary PH in a majority of patients with PH, which differs from some previous studies. Identifying the etiology of PH could drastically alter treatment strategies and has implications for transplant consideration. Further studies are needed to identify the clinical attributes that contribute to this process.

Complete transposition of the great arteries: surgical concepts for patients with systemic right ventricular failure following intraatrial repair.

One of the most serious late complications of the intraatrial baffle procedure (Mustard or Senning correction) in patients suffering from transposition of the great arteries, (TGA) is the late systemic right ventricular failure. Nearly all patients presenting with right ventricular dysfunction have severe associated tricuspid regurgitation. The surgical options for these patients include tricuspid valve reconstruction or replacement, staged conversion to the arterial switch operation and orthotopic heart transplantation. Review of 189 operative survivors who underwent the Mustard or Senning operation for TGA between 1970 and 1993 in our institution revealed 12 patients (6.3%) who died from severe systemic right ventricular dysfunction (mean follow-up 16+/-3.5 years), which was the most common cause of late death. All of them had concomitant severe tricuspid regurgitation. 7 patients (3.7%) died from sudden cardiac death. The actuarial survival at 10 years is 93% for simple TGA and 85% for TGA associated with ventricular septum defect or coarctation. At our institution, 4 adolescent or adult patients underwent tricuspid valve surgery; tricuspid valve replacement was performed in 2 patients and valve repair in 2 patients. In the mid-term follow-up, 2 of these patients died. Two additional patients underwent orthotopic heart transplantation, and one died on the waiting list. Staged conversion from the Senning/Mustard atrial repair to the arterial switch operation was initially reported by Mee. The procedure for pulmonary artery banding starts with inducing left ventricular reconditioning with subsequent arterial switch. The mortality of this two-staged procedure was as high as 20% to 30% in our early experience, and some of the candidates underwent heart transplantation. Tricuspid valve repair or replacement do not improve right ventricular function in patients with a failing right ventricle following the Mustard/Senning operation. Staged conversion to arterial switch may improve right ventricular function by decreasing the work load of the right ventricle and provides anatomic repair with left ventricle-to-aorta continuity. Orthotopic heart transplantation is the only alternative if the left ventricle does not respond to pulmonary artery banding.

Successful palliation of acute superior vena caval obstruction after the Senning operation

Superior vena caval obstruction after an intraatrial baffle procedure can lead to acute cerebral complications and hence requires immediate management. We present a case of successful palliation of acute superior vena caval obstruction after a Senning procedure by establishing a venous shunt between the innominate vein and pulmonary artery. This technique resulted in immediate hemodynamic and functional improvement that subsequently allowed for the enlargement of the superior vena cava–right atrial junction with a pericardial patch.

The Mustard procedure for correction of simple transposition of the great arteries before 1 month of age

Since April 1976, 34 infants (25 male and 9 female) less than 1 month of age underwent a Mustard intraatrial baffle procedure for repair of simple transposition of the great arteries. Thirty patients were less than 2 weeks old and 19 patients less than 1 week (mean 7.8 +/- 6 days). The weights ranged from 2.6 to 4.4 kg (mean 3.4 +/- 0.4 kg). Rashkind balloon atrial septostomy was performed in the first hours or days of life in 29 patients. The average interval from balloon atrial septostomy to baffle repair was 3.9 days (range 2 hours to 14 days). Mechanical ventilation was required in eight patients preoperatively and prostaglandin E1 was infused in 17 patients to maintain ductal patency. In all patients, the Mustard procedure was performed with the use of deep hypothermic circulatory arrest, averaging 53 minutes (range 37 to 82 minutes). The duration of postoperative intubation and ventilatory support averaged 1.7 +/- 1.0 days (range 1 to 5 days). Inotropic drugs were used in 24 patients during a period of 1.4 +/- 1.3 days (range 1 to 6 days) postoperatively. There were no hospital deaths. Follow-up evaluation has extended from 1 month to 14 years (mean 3 +/- 3 years). One infant died 2 months postoperatively as a result of milk aspiration; no cardiac defects were found at the autopsy. A second infant died at 1 year with right ventricular and tricuspid valve dysfunction. Baffle complications occurred in 6 of the 32 survivors, including superior vena caval stenosis in 4, inferior vena caval stenosis in 1, and pulmonary venous obstruction in 3. Reoperations for baffle obstructions were performed in three patients (8.8%) and balloon angioplasties in two. One patient required permanent pacemaker implantation. Results with the Mustard procedure before 1 month of age show that it can be performed with negligible mortality and a low incidence of late complications at an age comparable to when arterial switching would be performed. Until long-term studies demonstrate superiority of arterial operations, the low operative mortality favors continued evaluation of the neonatal Mustard repair as a valid alternative to the arterial switch.

Cine magnetic resonance imaging after surgical repair in patients with transposition of the great arteries.

Cine magnetic resonance imaging (MRI) was used for postoperative evaluation of eight patients who underwent intra-atrial baffle procedure for surgical repair of D-transposition of the great arteries (D-TGA). Their ages ranged from 9 months to 8 years. Younger patients were sedated with chloral hydrate (80 to 100 mg/kg) orally. MRI was performed with use of a General Electric Signa system operating at a field strength of 1.5 tesla. A body or head coil was used depending on the size of the patient. Images were obtained by use of a technique of gradient-recalled acquisition in steady state (GRASS) that utilizes a low flip angle and shorter repetition and echo times. Five patients had widely patent venae cavae and three had superior vena caval obstruction at the junction of the right atrium with a dilated azygos vein. There was no evidence of pulmonary venous obstruction in any of the patients. Right ventricular function was assessed in four patients and their ejection fractions ranged from 58% to 81%. Tricuspid and mitral regurgitation were observed in three and two patients, respectively. Both right and left ventricular outflow tracts were well visualized and showed no evidence of obstruction. Cine MRI is an entirely noninvasive, nonionizing, and safe procedure in young patients and appears to be a valuable alternative method for evaluating patients after surgical repair of D-TGA. With advancing technologies and an accumulation of experience with cine MRI, it appears that this new technique will play an important role in patient care for children with congenital heart disease.

Bovine Pericardium: A Source of Pulmonary Venous Obstruction in the Mustard Procedure

Following Mustard's popularization of the intraatrial baffle procedure for transposition of the great arteries, debate has persisted regarding the ideal materials to use. Reports of xenograft (i.e., bovine pericardium) as a suitable prosthetic material made it an appealing choice. We report our recent experience with 2 patients in whom bovine pericardium was used for atrial augmentation, with subsequent pulmonary venous obstruction. For this reason, we have abandoned this material as an acceptable prosthetic in the Mustard procedure.

Transposition of the great arteries with intact ventricular septum: Results of mustard and senning operations in 123 consecutive patients

The results of Mustard and Senning operations were reviewed in 123 consecutive patients operated on for d-transposition of the great arteries with intact ventricular septum. From 1972 to 1978, 66 patients had a Mustard operation at a mean age at operation of 15.5 months. The mean duration of the follow-up period was 43.5 months; 82% had a postoperative cardiac catheterization. From 1978 to 1980, 57 patients underwent a Senning operation at a mean age at operation of 6.6 months; the mean follow-up period was 13.6 months, and 75% had a postoperative catheterization. Within 30 days of operation, seven (11%) patients in the Mustard group died, and five (8%) died later while three (5%) in the Senning group died early and two (4%) died late. Pulmonary venous obstruction developed in four (6%) patients in the Mustard group, all requiring reoperation. Six (11%) in the Senning group had pulmonary venous obstruction; four (7%) had a reoperation. Systemic venous obstruction occurred in 32 patients in the Mustard group; reoperation was required in 11 (17%). Seven patients in the Senning group had systemic venous obstruction and three (5%) required reoperation. No patient in either group required reoperation for intracardiac shunts. One patient from each group died with sick sinus syndrome. Only two patients had transient right ventricular failure, both after the Senning repair. No patient in either group had tricuspid regurgitation. Recognizing the limitations inherent in comparing operations performed during separate time periods, the improvement in early operative mortality with the Senning operation makes it the intraatrial baffle procedure of choice for d-transposition of the great arteries with intact ventricular septum at our institution. Additionally, the use of autologous tissue with the Senning technique may prevent the progression of late baffle obstruction observed in some patients years after the Mustard operation. Until the long-term results are known, however, choice of operation is based on surgical preference.

Mustard operation in the 1st month of life

Since April 1976, nine infants less than 1 month of age underwent a Mustard intraatrial baffle procedure. All had transposition of the great arteries and were persistently symptomatic or hypoxic after the Rashkind balloon atrioseptostomy. Two had an associated large ventricular septal defect patched at the time of physiologic correction. The average age of the infants was 11.6 days (range 36 hours to 28 days). Weight averaged 3.4 kg (range 2.5 to 4.2). In all the Mustard procedure was performed using deep hypothermie circulatory arrest, averaging 71 minutes (range 48 to 88) at a mean core temperature of 13 °C. An average of 2.8 days of postoperative ventilatory assistance was required. One death occurred in a 28 day old male infant with an associated ventricular septal defect who, the morning after operation, had a sudden unresponsive cardiac standstill. The postoperative hospitalization period averaged 15 days (range 10 to 23). Follow-up evaluation has extended from 4 to 63 months (average 31). Six patients were restudied 2 to 21 months postoperatively. One had obstruction of the superior limb of the baffle, which had separated from the right atrial wall permitting a modest right to left shunt. She has had uneventful repair employing a unique modification of Senning's operation. Another child has asymptomatic partial obstruction of the superior limb of the baffle demonstrated angiographically. None has pulmonary venous obstruction and all have prevailing normal sinus rhythm. Significant right ventricular dysfunction has been demonstrated in one. Early correction in these persistently symptomatic or hypoxic neonates with transposition of the great arteries with or without a ventricular septal defect has obviated the need for palliative operations and produced gratifying early and late results.

Total correction of transposition of the great arteries: Conduction disturbances in infants younger than three months of age

Although total physiological correction of d-transposition of the great arteries (d-TGA) is technically feasible in infants, the optimal age for correction has remained controversial because of concern regarding major life-threatening arrhythmias and the long-term results of the intra-atrial baffle procedure. During a 3 year period, 54 children aged 4 days to 5 years, including 24 infants aged 3 months or younger, underwent the baffle procedure. Thirty-two children had simple transposition and underwent only placement of a pericardial baffle; no deaths occurred in this group. Twenty-two had complex transposition requiring in addition closure of a ventricular septal defect (VSD) and/or resection of outflow tract obstruction; there were four hospital and two late deaths in this group. A single operative approach was used in all patients. Sinus rhythm was present at discharge in 85 percent of the infants and 76 percent of the older children. Three factors--age, mode of cardiopulmonary support, and complexity of the lesion--influenced these results.

The Blalock-Hanlon procedure. Simple transposition of the great arteries.

Between 1959 and 1975 at St. Louis University Medical Center, 71 patients underwent surgery with the Blalock-Hanlon technique. Thirty-nine had simple transposition of the great vessels. The mean age at the time of operation was 3.4 weeks. Sixty-four percent were less than 1 month of age. Eighty-five percent survived the operation. In 11 the Blalock-Hanlon procedure was performed after failure of ballon septostomy. Arterial saturation was increased from a mean of 47% to 73%. There were three late deaths prior to Mustard repair (intra-atrial baffle procedure). Sixteeen patients underwent Mustard repair at a mean age of 4 years and a mean follow-up of 2 1/2 years. There were three deaths after surgery and three late deaths after the Mustard procedure. The Blalock-Hanlon procedure achieves prolonged palliation, avoiding an emergency Mustard procedure in infancy with its risk of late vena caval obstruction.

A New Operation for d-Loop Transposition of the Great Vessels

Transposition of the great vessels remains a major problem for the cardiac surgeon. Although the Mustard (intraatrial baffle) procedure has provided the means for physiological correction of this anomaly, there are many complications that plague the lives of the survivors. This report describes an operation that is essentially extracardiac and achieves the desired goal of simple switching of the great vessels. Future revisions of the outflow tract prosthesis may become a major problem, but probably less of one than the complications that have been and will be associated with the intraatrial baffle procedure.

Transposition of the great arteries: Reoperation for dysfunctional intra-atrial baffle

Correction of transposition of the great arteries is accomplished by a modified Rastelli procedure, if an adequate ventricular septal defect is present, or by an intra-atrial baffle procedure, if the ventricular septal defect is small or absent. The Albert or Mustard procedure for transposition of the great arteries should be regarded more precisely as the first stage in a series of procedures which may be necessary in any given case. Prosthetic material for the intra-atrial baffle is no guarantee that venous inflow obstruction will not eventuate. Less difficulty has resulted from initial use of pericardium. It is easier to redo an obstructing pericardial atrial baffle than a prosthetic baffle. A pseudointima attaches to either side of the plastic baffle, dictating total replacement with pericardium or a new prosthesis. Caval cannulation technique for correction of transposition of the great arteries depends on whether it is the initial correction or reoperation for intra-atrial baffle dysfunction that is being dictated by the intra-atrial anatomy in the two situations.