Risk of Type B Dissection in Marfan Syndrome The Cornell Aortic Aneurysm Registry

BACKGROUND With preventive aortic grafting decreasing the incidence of type A dissections in Marfan syndrome (MFS), most dissections are now type B, for which risk factors remain largely uncertain. OBJECTIVES We explored the determinants of type B dissection risk in a large, single-center MFS registry. METHODS Demographic and anthropometric features, cardiovascular disease, and surgical history were compared in patients with MFS with and without type B dissection. RESULTS Of 336 patients with MFS, 47 (14%) experienced a type B dissection (vs type A in 9%). Patients with type B dissection were more likely to have undergone elective aortic root replacement (ARR) (79 vs 46%; P < 0.001). Of the patients, 55% had type B dissection a mean of 13.3 years after ARR, whereas 45% experienced type B dissection before or in the absence of ARR; 41 patients (87%) were aware of their MFS diagnosis before type B dissection. Among those with predissection imaging, the descending aorta was normal or minimally dilated (<4.0 cm) in 88%. In multivariable ana -lyses, patients with type B dissection were more likely to have undergone ARR and independent mitral valve surgery, to have had a type II dissection, and to have lived longer. CONCLUSIONS In our contemporary cohort, type B dissections are more common than type A dissections and occur at traditional nonsurgical thresholds. The associations of type B dissection with ARR, independent mitral valve surgery, and type II dissection suggest a more severe phenotype in the setting of prolonged life expectancy.(J Am Coll Cardiol 2023;82:2009-2017) (c) 2023 by the American College of Cardiology Foundation.

Automated summary

The study explores the determinants of type B dissection risk in patients with Marfan syndrome (MFS) and finds that patients who undergo aortic root replacement surgery, independent mitral valve surgery, and have type II dissection are more likely to develop type B dissection.