Role of False Lumen Area Ratio in Late Aortic Events After Acute Type I Aortic Dissection Repair

Abstract

Background: The aim of this study was to investigate whether distal aortic maximum false lumen area (MFLA) ratio predicts late aortic dilation and reintervention after open repair of acute type I aortic dissection.

Methods: We analyzed 309 nonsyndromic acute type I aortic dissection patients who were treated with a repair to the proximal aorta between 1994 and 2017. In 230 patients who did not show completely thrombosed false lumen on postoperative computed tomography, the MFLA ratio (MFLA/aortic area) on the descending thoracic aorta (DTA) was measured with postoperative computed tomography. Patients were divided into 3 groups according to the quartile range of MFLA ratio: low MFLA, <0.62 (n = 57); intermediate MFLA, 0.62 to 0.81 (n = 116); and high MFLA, ≥0.82 (n = 57).

Results: The aortic expansion rate was significantly higher in the high MFLA group (11.1 ± 21.2 mm/y) compared with intermediate (3.0 ± 7.4 mm/y; P < .01) and low (0.6 ± 6.6 mm/y; P < .01) MFLA groups. High MFLA was found to be an independent risk factor for significant aortic expansion (adjusted hazard ratio, 5.26; 95% CI, 1.53-18.12; P < .01) and aorta-related reintervention (hazard ratio, 4.99; 95% CI, 2.23-11.13; P < .01), and the MFLA ratio was significantly related to proximal DTA reentry tears (adjusted odds ratio, 12974.3; P < .001; area under curve, 0.807).

Conclusions: A high MFLA ratio on the DTA after acute type I aortic dissection repair is associated with increased risk of late aortic reintervention and distal aortic dilation. A high MFLA ratio is strongly associated with proximal DTA reentry tears.