Functional assessment of bioprosthetic mitral valves by cardiovascular magnetic resonance: An in vitro validation and comparison to Doppler echocardiography

Figures

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  Fig. 1. The circulatory loop. A mock ventricle and heart valve imaging chamber a, pulsatile pump b, arterial compliance/resistance elements c, fill reservoir d, high-fidelity flow transducers e and the linear actuator f

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  Fig. 2. Cardiovascular magnetic resonance (CMR) images of the mock ventricle. Cine CMR images (right) depict systolic and diastolic function of a 27 mm bioprosthetic mitral valve (BMV)

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  Fig. 3. Normal and obstructed bioprosthetic mitral valves. Axial cine CMR images (above) and photographs (below) of normal 29 mm BMV, a valve with single leaflet obstruction, and a valve with double leaflet obstruction

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  Fig. 4. Phase contrast forward flow assessment. Phase contrast flow measurement at the valve tips of a 33 mm MV. LA = left atrium. LV = left ventricle. MV = mitral valve.

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  Fig. 5. CMR and Doppler-derived time velocity integral assessment. Phase contrast image for a 31 mm BMV at a forward flow volume of 90 mL/beat. Phase contrast time velocity integral (TVI) by CMR (left), and spectral Doppler (right)

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  Fig. 6. Plot of phase contrast CMR forward volume against reference volume. Pearson correlation analysis between PC- forward flow volume (PC-FFV) and flow transducer FFV (left). Bland-Altman plot and limits of agreement (right)

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  Fig. 7. Plot of phase contrast effective orifice area against Doppler method. Pearson correlation analysis between phase contrast effective orifice area (PC-EOA) and Doppler effective orifice area (EOA) (left). Bland-Altman plot and limits of agreement (right).

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  Fig. 8.. Clinical examples of normal and obstructed bioprosthetic valves assessed by CMR. A 65 year old male with a 29 mm bioprosthetic mitral valve. Phase contrast effective orifice area (PC-EOA) and DopplerEOA were similar and within normal range (left). A 60 year old male with dyspnea and a 25 mm bioprosthetic mitral valve. PC-EOA and DopplerEOA were both severity reduced, consistent with severe prosthetic valve stenosis (right)