Late results of surgical treatment of transposition of the great arteries

Results of the arterial switch operation for transposition of the great arteries with ventricular septal defect. Surgical considerations and midterm follow-up data

Between January 1983 and December 1987, 62 patients underwent an arterial switch operation for transposition of the great arteries with ventricular septal defect or double outlet right or left ventricle. There were three hospital deaths (4.8%), and no deaths occurred in neonates (less than 1 month of age, n = 18). There were three late deaths, one due to coronary obstruction and two due to pulmonary vascular obstructive disease. One child has been lost to follow-up. We have prospectively evaluated the remaining 55 survivors by clinical evaluation, echocardiography, cardiac catheterization, ambulatory electrocardiographic monitoring, and limited electrophysiologic studies. The mean length of follow-up has been 27 +/- 16 months since surgery. One child has required reoperation for a residual ventricular septal defect; no child has undergone reoperation for supravalvar pulmonary or aortic stenosis. Aortic regurgitation was identified in 12 children (22%), which was mild in 11 and moderate in one. One child has asymptomatic occlusion of the left main coronary artery, one child has a tiny right coronary artery-to-pulmonary artery fistula, and one child has abnormal left ventricular wall motion according to follow-up angiography. No other abnormalities of systemic (left) ventricular function have been identified at late follow-up. In addition to the two late deaths due to pulmonary vascular obstructive disease, three children, all of whom were repaired at more than 6 months of age, have elevated pulmonary vascular resistance. Notable postoperative arrhythmias include complete heart block in four patients and nonsustained supraventricular or ventricular tachycardia early after surgery in eight patients (all resolved without medication at later follow-up). Only two patients have evidence of sinus node dysfunction and have not required treatment. The low hospital mortality and encouraging early follow-up data represent a significant improvement over atrial level repairs, supporting the arterial switch operation as the procedure of choice for children who have transposition of the great arteries with ventricular septal defect or double outlet ventricle. Because of the potential for the development of early pulmonary vascular obstructive disease in these patients, repair is recommended within the first 2 months of life.

Ten years' experience with the Senning operation for transposition of the great arteries: physiological results and late follow-up

We report our results in 93 consecutive infants and children who underwent atrial repair of simple transposition of the great arteries using the Senning operation between February 1978 and February 1988. Mean age at operation was 5.6 +/- 6.3 months (range, 1 week to 4 years); 60 were less than 6 months old. There were 65 boys and 28 girls. Operative mortality was 5.4%, and there has been 1 late death. Average follow-up is 45.1 months with 39 followed more than 3 years and 25 followed more than 5 years. Postoperative cardiac catheterization was performed in 43 patients. Right ventricular ejection fraction at rest averaged 0.50 +/- 0.09 and was normal in 26 patients. Response of right ventricular ejection fraction to afterload stress was abnormal in 12 of 14 patients tested. Right ventricular ejection fraction increased normally during exercise in 6 patients, but was abnormal in 15. Mild tricuspid regurgitation was noted in 10 patients. Mild obstruction of the superior vena cava was noted in 4 patients. Baffle leak requiring reoperation occurred in 1 patient. Seventy-two of 80 patients are in sinus rhythm by latest electrocardiogram. Postoperative electrophysiological studies were performed in 34 patients and Holter monitoring was performed in 22. A major arrhythmia occurred in 8 patients: 3 required a pacemaker for junctional rhythm or sinus node dysfunction, 2 have symptomatic or inducible supraventricular tachycardia, 2 have junctional rhythm, and 1 has sick sinus syndrome. Eight additional patients have delayed sinus node recovery time. At last follow-up, 78 children (97.5%) are in New York Heart Association functional class I, and 2 (2.5%) are in class II.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term follow-up of right ventricular function after Mustard operation for transposition of the great arteries

As development of right ventricular (RV) failure is a potential risk after Mustard operation for transposition of the great arteries, 17 patients were reexamined 5-13 years postoperatively. Comparisons were made with healthy controls. There were no clinical signs of heart failure. Echocardiographically determined RV end-diastolic diameter was increased to 2.5 +/- 0.8 cm (controls: 1.5 +/- 0.4 cm, p less than 0.001). Comparison of RV systolic time intervals (STI) in patients with normal left ventricular (LV) STI revealed decreased RV function, with RPEPI 165 +/- 19 msec (controls 126 +/- 12, p less than 0.001) and RPEP/RVET 0.484 +/- 0.096 (controls 0.284 +/- 0.045, p less than 0.001). Nuclear angiography demonstrated decreased RV ejection fraction (EF), viz. 42.8 +/- 6.6% (normal RV 53 +/- 6%, LV 68 +/- 9%, p less than 0.001). Only two patients showed normal (5%) rise in RV-EF during exercise. There was no evidence of deterioration with passage of time. The results do not justify use of anatomic repair at our center, since the perioperative mortality might then be higher than in the Mustard or Senning procedures.

Results with the Mustard operation in simple transposition of the great arteries 1963-1985

From May 1963 to December 1985, 329 infants and children underwent repair of simple transposition of the great arteries (TGA) using Mustard's technique. To assess improvement, the patients were separated into two groups by date of operation: Group I, May 1963 to December 1973 (N = 106), and Group II, January 1974 to December 1985 (N = 223). The operative mortality was 11 (10.4%) in Group I and two (0.9%) in Group II. The 10-year actuarial survival rate was 73.4% in Group I and 93.7% in Group II. Baffle complications, similar in both groups, were identified in 81 patients; 19 were major, causing death or requiring reoperation. By latest electrocardiogram, 21 of 45 (46.7%) of Group I patients and 129 of 180 (71.7%) of Group II patients were in normal sinus rhythm. Late ambulatory electrocardiography, however, revealed that a majority of patients had sinus node dysfunction or other dysrhythmias. Right ventricular (RV) angiography revealed definite diminution of RV contractility in 14 (11%) of 126 children. At late follow-up, 113 of 148 (76%) children were in New York Heart Association (NYHA) Class I and 35 of 148 (24%) were in NYHA Class II. Thirty-five (21%) patients were on cardiac medication chiefly for dysrhythmia management. There has been significant improvement in the early and late mortality with the Mustard operation, and serious baffle complications are infrequent. Dysrhythmias continue to be a major problem but the surviving patients are clinically well and relatively few have significant RV dysfunction.

Pharmacologic inhibition of scar contracture of intracardiac prosthetic patches

Significant fibrosis and contracture often cause complications of pericardial and Dacron grafts within the heart. Both continue to be utilized because more suitable materials are unavailable. Newer prosthetic materials and the administration of drugs that might minimize intracardiac fibrosis and contracture after implantation were studied. Measured patches of three prosthetic materials were implanted into the right atrium of 18 dogs: 6 with expanded polytetrafluoroethylene (PTFE or Gore-Tex--W. L. Gore & Associates, Elkton, Md.), 6 with glutaraldehyde-preserved bovine pericardium, and 6 with Dacron patches. The animals were sacrificed after 8 weeks and gross and microscopic pathologic examinations were performed. The patch materials did not intrinsically shrink but all demonstrated marked distortion from the growth of surrounding scar tissue. In a fourth group of eight dogs with intraatrial Dacron patches, four were treated for 8 weeks with oral 3-aminopropionitrile fumarate, and four were not treated. A blinded observed evaluated the adhesions on a scale of 0 = no adhesions or patch distortion, to 4 = dense adhesions with marked distortion of the patches. The untreated dogs had dense adhesions of the lung and pericardium and the patches were encased in scar tissue with marked distortion. The average score was 3.5. The treated dogs had only minimal pleural adhesions and only a thin neointimal covering of the patch with virtually no distortion. The average score was 1.0 (P = 0.0032). The tensile strength of the healed atriotomies was evaluated with stress testing. The intact atrial wall ruptured at a force of 2.60 +/- 0.37 kg/m/sec2, the untreated atriotomy wound at 2.38 +/- 0.18 kg/m/sec2, and the treated atriotomy wound at 2.60 +/- 0.17 kg/m/sec2. There was no statistically significant difference among these groups. No other side effects of the 3-aminopropionitrile fumarate were noted, with only a single superficial wound infection caused by early postoperative trauma. Pharmacologic inhibition of scar formation minimized distortion and contracture of intracardiac prosthetic patches and decreased adhesions. Though further experimental evaluations are necessary, prolonged low-dose oral administration of beta-aminoproprionitrile (BAPN) may be beneficial in preventing complications of prosthetic implants and reoperative cardiac surgery in children.

Right and left ventricular function at rest and with exercise after the Mustard operation for transposition of the great arteries

Right and left ventricular function was assessed in 25 children (mean age at study 12.2 years and at operation 2.6 years) after a Mustard repair for transposition of the great arteries. Gated first pass and gated equilibrium radionuclide ventriculography was performed on all patients at rest and during supine bicycle exercise. The mean right ventricular ejection fraction did not increase with exercise by either technique. Individual results for right ventricular ejection fraction showed that with the gated equilibrium technique 71% had an abnormal exercise response (normal response being an increase in ejection fraction greater than 5%) and with the gated first pass technique 61% had abnormal results. Although the mean left ventricular ejection fraction increased significantly with exercise, 35% of patients had an abnormal exercise response with the equilibrium technique and 41% with the first pass technique. There was no evidence of a predictive relation between ventricular function and any clinical or haemodynamic variable examined. Covert right and left ventricular dysfunction can frequently be detected by exercise radionuclide ventriculography in long term survivors of repair for transposition of the great arteries. The prognostic consequences of these findings are unclear at present.

Long-term results after atrial repair of transposition of the great arteries in early infancy

Fifty-two patients younger than age 100 days who had an intact interventricular septum or a small ventricular septal defect underwent atrial repair of d-transposition of the great arteries (d-TGA). No patient died. To assess long-term results, we evaluated all 36 patients who had been followed for at least 1.5 years (mean 2.7 years) after surgery. The physical findings, chest roentgenograms, ECGs and echocardiograms were reviewed. Catheterization was done 6-60 months (mean 15 months) after surgery in 28 patients. Growth was normal in all but three patients. Neurologic development was abnormal in six patients (delayed speech in one patient, learning disability in three patients and preoperative cerebral infarction in two patients). The ECG showed sinus rhythm in 24 patients, minor abnormalities in nine and major dysrhythmias in three. Catheterization showed a normal cardiac index in all 28 patients. No intracardiac shunt was detected in 19 of 24 patients in whom complete oximetry data were available. One patient required reoperation for persistent atrial shunt and subsequent pacemaker placement. Two patients required baffle revision for symptoms related to superior vena caval obstruction. Right ventricular end-diastolic pressure was less than 15 mm Hg in all of 18 patients evaluated. We conclude that atrial repair of d-TGA in early infancy can be performed with a low mortality rate and a low incidence of late complications.