Characterization of syndromic, non-syndromic familial, and sporadic Type B Aortic Dissection

Abstract Objective Type B aortic dissection (TBAD) is commonly thought of as a sporadic event, however, there is an increasing body of literature that suggest that there are genetic factors that influence TBAD. Our aim is to determine the prevalence of heritable TBAD, defined as either syndromic TBAD or non-syndromic familial TBAD, and to detail the natural history and long term clinical outcomes compared to patients with “sporadic” TBAD without an identified syndrome or family history. Methods Clinical records for TBAD patients presenting to a single health care system between 1995 and 2017 were reviewed. Family history was obtained by interview and/or chart review. Syndromic TBAD is defined as TBAD in patients with Marfan, Loeys-Dietz, or vascular Ehlers-Danlos syndromes. Non-syndromic familial TBAD is defined as having a family history of aortic/arterial aneurysm/dissection and/or sudden death in a first or second degree relative in the absence of a known syndrome. Patients with syndromic and non-syndromic familial TBAD were compared to sporadic TBAD in terms of comorbid conditions, aortic repair, and mortality. Results Among 389 individuals (71.2% male) with TBAD, the etiology of TBAD was heritable in 27.9% of the cases (9.6% syndromic, 18.3% non-syndromic familial TBAD) and 72.1% sporadic. Patients with syndromic and non-syndromic familial TBAD were more frequently referred in the chronic phase than sporadic TBAD (35.5% vs. 44.1% vs. 25.8%, P=.014); and presented at younger ages (40.6 + 10.9 vs. 55.2 + 11.3 vs.62 + 12.9 years, P + 21 vs 178.9 + 39.3 vs 186.1 + 38.4, P=.01, diastolic 84.3 + 17.3 vs. 91.4 + 24.1 vs. 101.6 + 22.3, P=.001). Among patients with acute TBAD surviving to discharge from the initial hospitalization, thoracic endovascular repair (TEVAR) was performed in 115 individuals with no significant differences in TEVAR utilization in the three groups. However, syndromic and non-syndromic familial TBAD had more retrograde aortic dissection post TEVAR (33.3% vs. 15% vs. 3%, P=.006). They also had more arch repairs (30% vs 10.5% vs 3.6%, P + 13.1 vs. 65.7 + 13.7 vs. 72.8 + 12.7, P Conclusions In this single institutional experience, heritable TBAD accounts for 1 in 4 patients with TBAD. Non-syndromic familial TBAD is twice as common as syndromic TBAD and appear to share many clinical features. Identifying these patients early in their disease course and personalizing their care may improve their survival.