Aortic arch shape after arch repair predicts exercise capacity: a multicentre analysis.

Area of Science:

• Cardiovascular Surgery
• Pediatric Cardiology
• Medical Imaging

Background:

• Coarctation of the aorta repair often results in persistent exercise intolerance.
• The underlying hemodynamic mechanisms for reduced exercise capacity, in the absence of discrete recoarctation, are not fully understood.

Purpose of the Study:

• To investigate the relationship between aortic dimensions, descending aorta (DAo) flow, and exercise capacity in patients post-aortic arch repair.
• To explore the role of aortic size mismatch and DAo flow in long-term morbidity.

Main Methods:

• Analysis of cardiac magnetic resonance, cardiopulmonary exercise tests, and echocardiograms from 58 patients post-arch repair.
• Correlation of aortic arch measurements, including ascending aorta (AAo) to DAo diameter ratio, with % predicted VO2max.
• Subgroup analyses considering residual arch obstruction, bicuspid aortic valve, and hypertension.

Main Results:

• A negative correlation was found between the AAo to DAo diameter ratio and % predicted VO2max.
• Increased %DAo flow positively correlated with VO2max.
• Aorta size mismatch and reduced %DAo flow were significantly associated with decreased exercise capacity, particularly in patients without obstruction and with a bicuspid aortic valve.

Conclusions:

• Aortic size mismatch and altered DAo flow are key factors contributing to reduced exercise capacity after aortic arch repair.
• These hemodynamic factors provide a more comprehensive understanding of repair success beyond simple pressure gradients.
• Findings suggest a need to consider aorta size mismatch and DAo flow in defining successful aortic arch repair outcomes.