Abstract 14123: Interventricular Dyssynchrony Using Cine-Tagging MRI in Adult Congenital Heart Disease: Prediction of Right Ventricular Dysfunction

Abstract

PURPOSE: Right ventricular (RV) failure and ventricular dyssynchrony are strong determinants of prognosis in patients with adult congenital heart disease (ACHD). Although mechanical dyssynchrony using MRI has been already investigated to have detrimental effects on left ventricular (LV) dysfunction, its effect on RV dyfunction is not understood. The aim was to investigate the relationship between interventricular dyssynchrony using cine-tagged MRI and RV dysfunction in ACHD patients.

METHODS: 33 patients with ACHD (18 with repaired tetralogy of Fallot, 8 with atrial septal defect, and 7 with others; mean age: 34 year-old) underwent cardiac MRI. The time-curves of myocardial circumferential strains for biventricular free walls were delivered from the short-axis cine-tagging MR images. The contraction delay between RV and LV free walls was computed by the cross-correlation analysis of the two strain time-curves, and was defined as the interventricular dyssynchrony time (IVD; msec.). In addition, RV end-diastolic volume (RVEDV), ejection fraction (RVEF), and RV systolic pressure (RVSP) were measured by cine-MRI and RV catheter. Comparison of IVD was analyzed by Mann-Whitney U-test. The correlation between IVD and RVSP, RVEDV, or QRS width was analyzed by Pearson’s coefficient.

RESULTS: IVD was significantly greater for patients with RVEF &lt40% than for patients with RVEF &gt=40% (126±33 msec. vs. 62±48 msec. p<0.001). A significant correlation was obtained between IVD and RVSP (r=0.60, p<0.004). There was no correlation between IVD and RVEDV and between IVD and QRS width. Use of the cut-off of IVD (110msec.) differentiated patients with RVEF &lt40% from patients with RVEF &gt=40% with a sensitivity of 88% and a specificity of 88%.

CONCLUSIONS: Quantification of IVD was possible using cine-tagging MRI. IVD was related to RV pressure load due to residual hemodynamic issues in ACHD, and can become a candidate for the early detection of RV dysfunction.