Coagulation Defects Promote False Lumen Patency in Type A Aortic Dissection

Acute type A aortic dissection (TAAD) is associated with high mortality and morbidity. False lumen (FL) patency is associated with malperfusion, aortic expansion, reoperation and reduced survival. Our aim was to determine if coagulation defects predict the fate of the FL.

We conducted a single-centre, retrospective, case-controlled study of patients with TAAD. Patient demographics, preoperative characteristics, operative details, postoperative complications, and follow-up computed tomography scans at 1 year were compared between patients who presented with patent FL and thrombosed FL. Coagulopathy was evaluated using standard laboratory tests and thromboelastography on admission, postoperatively, and at discharge. The primary outcome was long-term survival.

Of 123 eligible patients with TAAD, 67% (n=79) had patent FL and 33% (n=38) had thrombosed FL. Patent FL was associated with higher in-hospital (38.0 % vs 5.3% p<0.05) and mid-term mortality (93.0% vs 7.0%, p<0.05), postoperative dialysis (5.1% vs 0, p=0.04) and gastrointestinal ischaemia (17.7% vs 5.3%, p<0.05) compared to the thrombosed FL group. Survival analysis included a maximum follow-up of 8.61 years and demonstrated reduced survival in patients with a patent FL (hazard ratio [HR] 10.2, 95% confidence interval [CI] 3.00-34.6, p<0.001). Multivariable logistic regression analysis identified preoperative activated partial thromboplastin time (APTT), postoperative day 1 APTT, R value and alpha angle as independent predictors of patent FL.

Patients with a patent FL have a higher risk of mid- and long-term mortality and postoperative morbidity. Abnormalities in coagulation tests, particularly of the intrinsic pathway, are associated with FL patency. The coagulation cascade represents a novel therapeutic target to promote FL thrombosis.