Cine MR Imaging in Aortic Stenosis

Abstract

The potential of cine magnetic resonance (MR) imaging for the assessment of aortic stenosis (AS) was investigated in 17 patients. The severity of AS was graded by continuous wave Doppler ultrasound as severe in 10 of 17 patients and as moderate in the remaining 7 patients. Cine MR demonstrated a flow disturbance proximal and/or distal to the aortic valve plane in all 17 patients. This flow disturbance was seen as a signal void with four typical features: (a) a high-velocity jet phenomenon distal to the valve plane during systole, closely related to the stenotic orifice (8 of 17); (b) a turbulent systolic signal void in continuity with the jet, which propagated for a variable extent into the aorta (17 of 17); (c) a signal void just proximal to the valve plane during systolic ejection, reflecting prestenotic acceleration of blood flow (5 of 17); and (d) a void at the valve plane due to valvular calcifications (14 of 17). The following features or a combination thereof appeared to correlate with more severe grades of AS as visualized on cine MR display: (a) identification of narrow high-velocity jet phenomenon; (b) extensive propagation of the turbulent signal void into the aorta; and (c) presence of a prestenotic acceleration effect. Assessment of the severity of AS with cine MR is still limited. However, cine MR can identify the presence of AS and several flow phenomena that correlate with more severe degrees of stenosis.