Abstract 19131: Wave Reflections are Independently Associated with Left Ventricular Hypertrophy in Aortic Stenosis

Introduction: Aortic stenosis induces a hemodynamic burden on the left ventricle (LV) that leads to geometric changes. Yet the additional impact of the arterial system on the LV is often ignored. Hypothesis: We hypothesized that arterial load is associated with LV mass in subjects with aortic stenosis, independently of aortic valve area (AVA). Methods: We studied 40 subjects with aortic stenosis. We measured LV mass and cardiac output with SSFP MRI cine imaging, and determined MRI AVA using planimetry. Central pressures were obtained using carotid tonometry, and ascending aortic flow was quantified with through-plane phase-contrast MRI. We assessed the following indices of pulsatile load via pressure-flow analyses: total arterial compliance (TAC), proximal aortic characteristic impedance (Zc), and forward (Pf) and reflected wave (Pb) amplitude. We assessed the relationship between arterial load and LV mass. Results: Among 40 subjects with AS, 16 subjects had mild AS, 20 subjects had moderate AS, and 4 subjects had severe AS. In models that adjusted for AVA and resistive load (SVR), only reflected wave amplitude (Pb, standardized β=0.52, P=0.007) was significantly associated with LV mass (Table). Conclusion: Pulsatile load is an important and often overlooked determinant of LV mass in aortic stenosis. After adjustment for SVR and aortic valve area, reflected waves were significantly associated with LV mass, implicating late systolic load in LV hypertrophy in this condition. ![][1] [1]: /embed/graphic-1.gif