Small left coronary arteries after arterial switch operation for complete transposition

Area of Science:

• Pediatric Cardiology
• Congenital Heart Disease Surgery
• Cardiovascular Imaging

Background:

• Post-arterial switch operation (ASO) in patients with complete transposition of the great arteries (TGA), myocardial perfusion and ventricular function can be compromised.
• The underlying mechanisms for these functional deficits remain incompletely understood.

Purpose of the Study:

• To investigate coronary artery dimensions in patients following ASO for TGA.
• To assess the relationship between coronary artery size and ventricular function mid-term after surgery.

Main Methods:

• Coronary artery diameters (right, left main trunk, LAD, circumflex) were measured using computer-assisted densitometry.
• Measurements were performed in 86 patients at 8-86 months (mean 47.5 months) post-ASO.
• Z scores were calculated and compared to controls; correlation with left ventricular ejection fraction (LVEF) was assessed.

Main Results:

• Right coronary arteries showed a trend towards larger Z scores (+2.0 +/- 0.3).
• Left anterior descending and circumflex coronary arteries were significantly smaller (Z scores -1.8 +/- 0.3 and -1.5 +/- 0.3, respectively).
• Overall cross-sectional area of the three assessed coronary arteries was reduced (Z score -1.5 +/- 0.3) and did not correlate with LVEF.

Conclusions:

• Mid-term follow-up after ASO for TGA reveals hypoplasia of the left coronary arteries.
• The clinical significance of these findings requires further investigation through careful, long-term follow-up studies.
• This highlights potential implications for myocardial perfusion and ventricular health in TGA survivors.