Time course and predictors for neoaortic root dilatation and neoaortic valve regurgitation during adult life after arterial switch operation

INTRODUCTION AND OBJECTIVES

There are limited data on the long-term development of neoaortic root dilatation (NRD) and neoaortic valve regurgitation (AR) after arterial switch operation (ASO) for transposition of the great arteries during adult life.

METHODS

We performed a retrospective longitudinal analysis of 152 patients older than 15 years who underwent ASO for transposition of the great arteries and who were followed-up for 4.9±3.3 years in 2 referral centers. Sequential changes in body surface-adjusted aortic root dimensions and progression to moderate/severe AR were determined in patients with 2 or more echocardiographic examinations. Risk factors for dilatation were tested by Cox regression to identify predictors of AR progression.

RESULTS

At baseline, moderate AR was present in 9 patients (5.9%) and severe AR in 4 (2.6%), of whom 3 had required aortic valve surgery. Initially, the median neoaortic root dimension was 20.05±2.4mm/m², which increased significantly to 20.73±2.8mm/m² (P <.001) at the end of follow-up. The mean change over time was 0.14mm/m²/y (95%CI, 0.07-0.2). Progressive AR was observed in 20 patients (13.5%) and 6 patients (4%) required aortic valve surgery. Progressive AR was associated with bicuspid valve, AR at baseline, NRD at baseline, and neoaortic root enlargement. Independent predictors were bicuspid valve (HR, 3.3; 95%CI, 1.1-15.2; P=.037), AR at baseline (HR, 5.9; 95%CI, 1.6-59.2; P=.006) and increase in NRD (HR, 4.1 95%CI, 2-13.5; P=.023).

CONCLUSIONS

In adult life, NRD and AR progress over time after ASO. Predictors of progressive AR are bicuspid valve, AR at baseline, and increase in NRD.