Extent of Preoperative False Lumen Thrombosis Does Not Influence Long‐Term Survival in Patients With Acute Type A Aortic Dissection

Abstract

BackgroundPartial thrombosis of the false lumen has been related to aortic growth, reoperations, and death in the chronic phase of type B and repaired type A aortic dissections. The impact of preoperative false lumen thrombosis has not been studied previously. We used data from a contemporary, multinational database on aortic dissections to evaluate whether different degrees of preoperative false lumen thrombosis influenced long‐term prognosis.Methods and ResultsWe examined the records of 522 patients with surgically treated acute type A aortic dissections who survived to discharge between 1996 and 2011. At the preoperative imaging, 414 (79.3%) patients had patent false lumens, 84 (16.1%) had partial thrombosis of the false lumen, and 24 (4.6%) had complete thrombosis of the false lumen. The annual median (interquartile range) aortic growth rates were 0.5 (−0.3 to 2.0) mm in the aortic arch, 2.0 (0.2 to 4.0) mm in the descending thoracic aorta, and similar regardless of the degree of false lumen thrombosis. The overall 5‐year survival rate was 84.7%, and it was not influenced by false lumen thrombosis (P=0.86 by the log‐rank test). Independent predictors of long‐term mortality were age >70 years (hazard ratio [HR], 2.34; 95% confidence interval [CI], 1.20 to 4.56, P=0.012) and postoperative cerebrovascular accident, coma, and/or renal failure (HR, 2.62; 95% CI, 1.40 to 4.92, P=0.003).ConclusionsPatients with acute type A aortic dissection who survive to discharge have a favorable prognosis. Preoperative false lumen thrombosis does not influence long‐term mortality, reintervention rates, or aortic growth.

False Lumen Status in Patients With Acute Aortic Dissection: A Systematic Review and Meta‐Analysis

“…For type A studies,22, 26, 27 the pooled HR for long‐term mortality with partial thrombosis of the false lumen was 1.75 (95% CI, 0.88–3.45; P =0.211; Figure 3) with moderate heterogeneity (I 2 =68.1%; P =0.044). Among type B studies,20, 29, 30 the pooled HR for long‐term mortality with partial thrombosis of the false lumen was 2.24 (95% CI, 1.37–3.65; P =0.001; Figure 3) with no heterogeneity (I 2 =0.0%; P =0.371; Figure 3).…”

“…Four studies17, 22, 26, 27 examined the association between the false lumen status and AAD outcomes in type A patients, and another 6 studies18, 19, 20, 28, 29, 30 examined associations in type B patients. One study21 included both type A (73%) and type B (27%) AAD; in subgroup analysis based on the Stanford classification, this study was placed in the type A group.…”

“…In AAD type A, the IRAD data reported that the rates for overall 5‐year survival and major adverse events were not influenced by false lumen thrombosis (using the log‐rank test) 22. Conversely, another 2 studies, both having relatively small sample sizes, showed that the presence of a partial false lumen was an independent predictor of long‐term mortality, compared with a completely patent false lumen, after adjusting for confounding factors 26, 27.…”

“…Blood flow through the false lumen will be altered by resection of the primary tear and aortic reconstruction, because thrombosis of the false lumen is promoted 22. Thus, the false lumen status may be altered postoperatively.…”

“…This conclusion supports the concept that a wide surgical extent during initial repair could decrease late mortality rates for AAD type A patients. However, some studies have shown that preoperative residual patency of the false lumen is not a predictor of 5‐year mortality in AAD,21 and that partial thrombosis is not associated with long‐term mortality, reintervention rates, or aortic growth in type A cases after a 5‐year follow‐up 22. Therefore, conclusions regarding the association between the status of the false lumen and poor outcomes in AAD are conflicting.…”