Coronary Artery Problems Late After Arterial Switch Operation for Transposition of the Great Arteries

Abstract

Background:The incidence of late coronary artery abnormalities after arterial switch operation (ASO) for d-loop transposition of the great arteries may be underestimated. Methods and Results:We retrospectively reviewed coronary artery morphology in 40 of 97 patients who survived the first year after ASO. Seven asymptomatic patients developed significant late coronary artery abnormalities. One patient died suddenly at home with severe left coronary artery (LCA) ostial stenosis at age 3.8 years. The second patient collapsed during exercise at age 9.6 years due to ventricular fibrillation and severe LCA ostial stenosis despite prior negative exercise stress test (EST) and myocardial perfusion imaging (MPI). The third patient was found to have moderate ostial stenosis of the LCA with negative EST and MPI. The fourth patient with exercise-induced ST-T depression and myocardial perfusion defect was shown to have complete LCA occlusion with collateral vessel formation. Three other patients had complete proximal obliteration of either of the coronary arteries with collateral supply. An additional 4 asymptomatic patients had trivial-mild narrowing of the LCA on routine selective coronary angiogram. Conclusions:Incidence of late coronary stenosis or occlusion was not infrequent after ASO (11.3%) and presented usually without preceding symptoms and often after negative non-invasive screening. We advocate routine coronary imaging in all patients after ASO before they participate in competitive sports. 2373 Late Coronary Problems After ASO Laboratory). MPI was performed with technetium-99 m sestamibi injection, and perfusion imaging was obtained before and after exercise. Studies were read by a radiologist specialized in nuclear medicine. All cardiac catheterizations and angiograms were reviewed by W.R., Director of the Cardiac Catheterization Laboratory. All study results and original images were presented and carefully discussed in a weekly Multidisciplinary Case Conference at Nemours Cardiac Center for final consensus among the group, which included all attending cardiologists, intensivists, surgeons, and anesthesiologists prior to any critical decisions being made.

Can we predict potentially dangerous coronary patterns in patients with transposition of the great arteries after an arterial switch operation?

“…5 We know that the frequency of such features is significant, 5,6,7,19 and our study shows that they cannot be reliably predicted using basic screening tests. A similar conclusion was published by Tsuda et al 20 For responsible patient management, for example, in terms of sports qualification, further follow-up visits and establishing the real impact of the coronary anatomy during the post-operative follow-up are needed to determine the exact coronary pattern in every single patient after an arterial switch operation.…”

Functional outcomes in children with anatomically repaired transposition of the great arteries with regard to congenital ventricular septal defect and coronary pattern

“…There are currently many exercise studies in children,27 28 mainly focusing on peak oxygen uptake as the outcome parameter, that have shown that exercise is safe and with a minimum of structured training, improvements can be achieved. However, before participation an incidence of coronary stenosis or occlusion has to be ruled out because it is not an infrequent sequel after reimplantation of the coronary arteries in anatomical repair of TGA 29. Particularly dangerous in terms of exercise is that children do not get angina after anatomical repair of TGA as the pain fibres to the heart have been transected which take time to grow back 29…”

Coronary artery disease in patients with congenital heart defects

“…Coronary artery obstruction has been reported in 6.8% through 11.3% of patients with transposition of the great arteries (TGA) after arterial switch operation, but these are usually due to mechanical obstruction of the vessels [41,42]. Freedom from coronary events was 88.1 AE 6.4% at 22 years in one study comprising 95 patients [43].…”