Abstract 11993: Evaluation of Cardiac Valvular Regurgitant Lesions by Cardiac MRI SSFP Sequences: Comparison of Semi-quantitative vs. Quantitative Methods

Abstract

Introduction Cardiac Magnetic Resonance (CMR) imaging generally allows more accurate and valid quantification of structure and function than echocardiography. Recently, CMR technological advancements has made evaluation of cardiac valves more reliable. However, there are no studies in the literature that compare semi-quantitative grading (SQG) using CMR SSFP sequences with quantitative grading (QG) based on stroke volumes and phase velocity mapping (PVM). Hypothesis We propose SQG of cardiac valvular regurgitations based on CMR SSFP sequences is feasible and highly correlated with standard CMR QG methods. Methods CMR data Jan 2007-Dec 2011 was prospectively evaluated for valvular regurgitant lesions. Patients were included if they had RV and LV volumetrics based on CMR SSFP sequences and PVM across the aortic and pulmonic valves with reported regurgitant volumes and fractions. Patients were excluded if they had prosthetic valves, cardiac arrhythmias or intra-cardiac shunts. Regurgitant lesions were semi-quantitatively (visually) graded on a standard scale of 0 to 4 and compared with quantitative regurgitant fractions. Correlations were evaluated by Spearman's rho formula and kappa for intra and inter observer variability was obtained on 30% of the study sample. Results Ninety seven (n=97) pts with a combined 134 valvular regurgitations (MR, AR, TR, and PR) were analyzed by semi-quantitative and quantitative methods. There were 58 males (60%), age 55±18 yrs. There were 44 mitral, 50 aortic, 29 tricuspid and 11 pulmonary regurgitant lesions. The correlation between SQR vs. QG yielded the following results: r=0.67 (MR, r=0.66; AR, r=0.68; TR, r=0.68; PR r=0.70, p<0.002 for all). The results for QG vs. SQG accounting for clinically significant differences of ± 1 grade for the group were as follows: r= 0.95 p<0.001 (MR, r=0.91; AR, r=0.96 ; TR, r=0.99; PR, r=0.93, p<0.001 for all). No discrepancy between surgical regurgitation was present (3+ vs. 4+). Weighted kappa results were 0.67 and 0.61 for intra and inter observer variability. Conclusions Visual assessment of cardiac regurgitant lesions is reliable, accurate and reproducible when compared to quantitative analysis via CMR confirming confirming CMRI robust role in assessing regurgitant lesions.