Routine Cine-CMR for Prosthesis Associated Mitral Regurgitation: A Multicenter Comparison to Echocardiography

Abstract

Background/Aim MR is an important complication after PMV. Transthoracic echocardiography is widely used to screen for native MR, but can be limited with PMV. Cine-CMR holds potential to non-invasively assess regurgitant severity based on MR-induced inter-voxel dephasing. This study evaluated routine cine-CMR for visual assessment of prosthetic mitral valve (PMV) associated mitral regurgitation (MR). Methods Routine cine-CMR was performed at 9 sites. A uniform protocol was used to grade MR based on jet size in relation to the left atrium (mild <1/3, moderate 1/3–2/3, severe >2/3): MR was graded in each long axis orientation, with overall severity based on cumulative grade. Cine-CMR was also scored for MR density and pulmonary vein systolic flow reversal (PSFR). Visual interpretation was compared to quantitative analysis in a single center (derivation) cohort, and to transesophageal echocardiography (TEE) in a multicenter (validation) cohort. Results The population comprised 85 PMV patients (59% mechanical, 41% bioprosthetic). Among the derivation cohort (n=25), quantitative indices paralleled visual scores, with stepwise increases in jet size and density in relation to visually graded MR severity (both p=0.001): Patients with severe MR had nearly a 3-fold increase in quantitative jet area (p=0.002), and 2-fold increase in density (p=0.04) than did others. Among the multicenter cohort, cine-CMR and TEE (Δ=2±3 days) demonstrated moderate agreement (κ=0.44); 64% of discordances differed by ≤ 1 grade (Δ=1.2±0.5). Using a TEE reference, cine-CMR yielded excellent diagnostic performance for severe MR (sensitivity, negative predictive value=100%). Patients with visually graded severe MR also had more frequent PVSFR (p<0.001), denser jets (p<0.001), and larger left atria (p=0.01) on cine-CMR. Conclusions Cine-CMR is useful for assessment of PMV-associated MR, which manifests concordant quantitative and qualitative changes in size and density of inter-voxel dephasing. Visual MR assessment based on jet size provides an accurate non-invasive means of screening for TEE-evidenced severe MR.

Recommendations for the imaging assessment of prosthetic heart valves: a report from the European Association of Cardiovascular Imaging endorsed by the Chinese Society of Echocardiography, the Inter-American Society of Echocardiography, and the Brazilian Department of Cardiovascular Imaging†

“…67 Turbulent flow through a regurgitant orifice is easily visible with SSFP (visualization of signal voids due to spin dephasing in moving protons). 63,64 PHV anatomy can be imaged by acquisition of standard short-axis, two-, three-, and four-chamber long-axis views in combination with oblique long-axis cines orthogonal to the line of coaptation. 68 Leaflet motion restriction may be identified.…”

“…15,21,27,29,134 Cinefluoroscopy, cardiac CT, or CMR can be used as complementary tools, if needed (see above). 39,42,64 On TTE, parasternal long-and short-axis views, and all apical views with multiple angulation and off-axis cuts are needed to scan the whole sewing ring, the mitral subvalvular apparatus, and the leaflet/occluder(s) motion. The stents of biological valve are often well seen in the apical four-chamber view.…”

Pivotal role of cardiac MRI in mitral valve regurgitation

“…Cine-CMR is useful for the assessment of prosthetic mitral valve-associated MR, which manifests concordant quantitative and qualitative changes in size and density of inter-voxel dephasing. It provides an accurate non-invasive means of screening for TEE-evidenced severe MR (60) In one of the these studies, clinical benefit and LV remodeling had good correlation with CMR in post-procedural follow up. (61,62) This signifies an emerging role of CMR in clinical follow up of this subgroup of patients.…”

A review of the pivotal role of cardiac MRI in mitral valve regurgitation

“…Cine‐CMR is useful for the assessment of prosthetic mitral valve‐associated MR, which manifests concordant quantitative and qualitative changes in size and density of inter‐voxel dephasing. It provides an accurate noninvasive means of screening for TEE‐evidenced severe MR 70 . In one of these studies, clinical benefit and LV remodeling had good correlation with CMR in post‐procedural follow‐up.…”