Poster Session O - Surgical Medicine

Marcell Fontos^{1}, Éva Kis^{1}, László Ablonczy^{1}, Zsolt Prodán^{1}, Zsolt Nagy^{1}, Márton Vértesaljai^{1}, István Kozma^{1}, Hajnalka O. Bálint^{1}

1: Gottsegen National Cardiovascular Center

Introduction: Coronary events are life-threatening long-term complications of the arterial switch operation (ASO) for complete transposition of the great arteries. The positive effect of a more lateral left coronary artery reimplantation on reducing coronary risk is widely accepted, while less is known about the dimensions of the coronary arteries.

Aims: The aim of this study was to assess the dimensions of the reimplanted coronary arteries and their relationship with the geometric characteristics to gain a better understanding on the development of coronary complications.

Method: In a retrospective study, CT coronary angiograms of 78 asymptomatic pediatric patients performed at the age of 10.7 (6.3-17.8) years were evaluated. The position of the ostia, the branching angles and the diameters of the coronary arteries were determined in a subgroup of 51 patients presenting the usual (1LCx-2R) preoperative coronary anatomy.

Results: Mean Z-score of mid-LMCA, proximal LAD, proximal LCX and proximal RCA diameters were 0.7±1.2, -0.4±1.1, -0.1±1.1 and -0.3±1.1 respectively. The closer position of the LMCA ostia to the MPA was associated with a more acute angulation (p<0.001). High risk left coronary artery geometric characteristics (anterior reimplantation, acute branching angle) were associated with smaller ostial LMCA diameter Z-scores (p<0.001). Ostial LMCA diameter Z-score correlated negatively with the interval between the ASO and the CT angiography (p=0.003). Ostial-to-mid-LMCA diameter ratio was <1 in 37/51 (73%) cases. High risk left coronary artery geometric characteristics were associated with a smaller ostial-to-mid-LMCA diameter ratio (p=0.015 for the reimplantation site, p=0.003 for the branching angle). Ostial-to-mid-LMCA diameter ratio correlated negatively with the interval between the ASO and the CT angiography (p=0.022).

Conclusion: Even though high risk left coronary artery geometric characteristics were associated with smaller ostial LMCA diameter Z-scores, most of the coronary diameters fell within the normal range, which suggests normal overall development. To prove the clinical relevance of the smaller ostial diameter of high risk left coronary arteries and the decrease of ostial coronary artery Z-scores by time needs further follow-up studies.

Funding: The authors did not receive support from any organization for the submitted work.