Variation of Coronary Artery Anatomy in

Transposition of the Great Arteries

Piya SamankatiwatRamathibodi Hospital

Mahidol University

Introduction

Anatomical variation of coronary artery in TGA is complicated.Literally, classification of coronary artery in TGA is inhomogeneous. The usual type is not that usual, only just slightly more than 60%Correct preoperative recognition is sometimes difficult.Influence on outcome of surgery is still controversial.

Definition of coronary artery

Coronary artery morphology

Patterns in TGA (Leiden Convention)

The “normal” coronary disposition in TGA is: 1LCx 2R (the disposition appears inverted as compared with the disposition in the normal heart). The most frequent anomalies encountered are: 1L 2RCx, 1Cx 2RL, 1R 2LCx, 2LCxR, 2RLCx, 2CxRL,1RLCx.These may pose special surgical problems or even contraindicate the switch at arterial level. in particular single coronary artery and intramural type.

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Volume1 No.1 2006

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Wernovsky G and Sanders SP Coron Artery Dis. 1993;4:148–157.

Pasquali et al. Circulation. November 12, 2002

Patients and method

An observational study20 consecutive patients underwent arterial switch operation.Anatomical patterns of coronary arteries were recorded.Special concern on difficult types.

Results

Median age 12 days (3-480 days)Male:Female 3:114 newborns, 5 infants and 1 child One Dextrocardia

Dextrocardia case

Results

1LCx 2R 60% (n=12) 1 usual type with separated orifice of right ventricular branch from sinus 1. 1L 2RCx 25% (n=5) 2RLCX 15% (n=3) 2 cases posterior course of LCA1 case anterior course

Results

1LCx 2R

60 %N=12

0 %1L 2RCx25 %N=5

2RLCx15 %N=3

0 % 0 % 0 %

Conclusion

Coronary artery pattern in TGA was inconsistent.Usual pattern in only 60 %Difficult to determine if higher risk of arterial switch operation was associated with a particular type of coronary artery anatomy. Our series: all single coronary artery cases survive.The value of preoperative recognition of the pattern of coronary artery and outcome of surgery for TGA is still skeptical. Further observation

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