Effect of Aortic Stiffness on Left Ventricular Long-Axis Systolic Function in Adults with Marfan Syndrome

Introduction: Several studies have documented increased aortic stiffness in patients with Marfan syndrome (MFS) using echocardiography and magnetic resonance imaging. Recent studies have also shown primary myocardial impairment in MFS. We investigated whether left ventricular (LV) function could be further impaired when acting against a stiff vascular system. Methods: Twenty-six MFS patients (mean age 30 +/- 2 years, 17 males) and 30 normal controls were examined. Mitral annular displacement, as a surrogate for LV systolic function, was evaluated from septal, anterolateral, anterior and inferior regions using M-mode and tissue Doppler imaging. Septal/anterolateral and anterior/inferior M-mode displacement measurements were normalised by dividing them by the longitudinal inner distance obtained at end diastole from the 4- and 2-chamber views, respectively. Carotid-femoral and carotid-radial (CF and CR) pulse wave velocities (PWV) were determined using an automated applanation tonometry device. Central aortic pressure was assessed by recording radial waveforms with the tonometer and central waveforms were reconstructed using a generalised transfer function. Results: CF- and CR-PWV were significantly increased in the patient group (p<0.001), whilst mitral annular displacement measurements were significantly reduced (p<0.001, all regions). Regression analysis demonstrated that the disease status and CF-PWV were strongly associated with reduced LV systolic function (p<0.001, p=0.002, respectively). Conclusions: Our study showed reduced LV systolic function and increased aortic stiffness in MFS patients. The efficiency of a fibrillin-1 deficient heart may be further reduced by ejection into a stiff vascular system. Care should be taken to ensure that any treatment regime addresses both increased aortic stiffness and myocardial dysfunction in MFS.