Effects of Beta-adrenergic in Adults w/Transposition of Great Arteries on Systemic Ventricular Function

Many children with transposition of the great arteries who underwent atrial inflow correction using the Mustard or Senning operation are now adults. While their short- and midterm prognosis have been good, their life expectancy is limited by the onset of serious cardiovascular complications including arrhythmias, systemic (morphologically right) ventricular dysfunction and sudden cardiac death.

The ability of the morphological right ventricle (RV) to support the systemic circulation is limited. It has been postulated that perfusion and wall motion abnormalities are common in the systemic RV late (10-20 years) after Mustard's operation. Poor ventricular function causes progressive RV enlargement and systemic atrioventricular valve insufficiency, resulting in congestive heart failure (CHF). Deterioration in systolic function of the systemic ventricle is a major determinant of survival in these patients.

Little is known about the most effective therapy of progressive systemic RV dysfunction in these patients. Despite several recent studies demonstrating the benefit of beta-adrenergic blocking agents in improved left ventricular function in adults with heart failure and left ventricular dysfunction, there have been no reports of the use of beta-adrenergic blocking agents in adult patients with ventricular dysfunction due to congenital heart disease. This data collection study will be a single center, retrospective study; a chart review of patients with TGA (either DTGA or LTGA) and systemic right ventricular dysfunction.

Patient Population:

Patients followed-up at Emory University Hospital and The Emory Clinic who meet the following inclusion criteria:

1. Age ≥ 18 years
2. Diagnosis: Complete d-TGA or Congenitally Corrected TGA with a systemic morphologic right ventricle
3. Patients > 18 years of age seen at The Emory Clinic and Emory University Hospital with transposition of the great arteries
4. Systemic ventricular ejection fraction < 50% with or without a clinical diagnosis of heart failure
5. Echocardiogram performed between January 1, 1997and February 1, 2006

Future Directions:

The effects of beta-adrenergic blocking agents in patients with TGA and congestive heart failure due to systemic ventricular dysfunction have never been studied. To our knowledge, only one case report suggests that carvedilol may potentially improve systemic ventricular functions and volumes in these patients. This study will identify the potential merits of beta-blocker therapy in patients with TGA and CHF and could theoretically lead to a multi-institutional prospective analysis of beta-blocker therapy in adult patients with congenial heart disease and CHF.