Ventricular-Vascular Coupling in Marfan and Non-Marfan Aortopathies

Background Marfan syndrome (MFS) and familial non-syndromal thoracic aortic aneurysm and dissection (ns-TAAD) are genetic aortopathies causing aortic dilatation with increased aortic stiffness. Left ventricular (LV) contractility and ventricular-vascular coupling index (VVI) were compared between MFS and ns-TAAD and determinants of VVI were investigated.
Methods and Results Patients with MFS and ns-TAAD were studied by echocardiography and compared with controls. Aortic geometry, hemodynamics, LV work, LV contractility (end-systolic elastance [Ees]), and VVI were documented. Aortic sinuses were equally dilated in MFS and ns-TAAD compared to controls. Aortic stiffness index was increased in MFS and ns-TAAD versus controls; LV stroke work was unchanged in MFS compared to controls but increased in ns-TAAD. The LV Ees was reduced in MFS compared to controls but increased in ns-TAAD and VVI was abnormal in MFS compared to controls and ns-TAAD. Treatment with β-blockers was associated with partial normalization of VVI in MFS. A VVI =0.8 was associated with increased risk of death and heart failure in MFS.
Conclusions Left ventricular contractility and ventricular-vascular coupling are abnormal in MFS but preserved in ns-TAAD, and are independent of aortic stiffness, consistent with intrinsic impairment of myocardial contractility in MFS.