Multi-parametric quantification of tricuspid regurgitation using cardiovascular magnetic resonance: A comparison to echocardiography.

Velocity-encoding is used to quantify tricuspid regurgitation (TR) by cardiovascular magnetic resonance (CMR), but requires additional dedicated imaging. We hypothesized that size and signal intensity (SI) of the cross-sectional TR jet area in the right atrium in short-axis steady-state free-precession images could be used to assess TR severity. We studied 61 patients with TR, who underwent CMR and echocardiography within 24h. TR severity was determined by vena contracta: severe (N=20), moderate or mild (N=41). CMR TR jet area and normalized SI were measured in the plane and frame that depicted maximum area. ROC analysis was performed in 21/61 patients to determine diagnostic accuracy of differentiating degrees of TR. Optimal cutoffs were independently tested in the remaining 40 patients. Measurable regions of signal loss depicting TR jets were noted in 51/61 patients, while 9/10 remaining patients had mild TR by echocardiography. With increasing TR severity, jet area significantly increased (15±14 to 38±20mm2), while normalized SI decreased (57±27 to 23±11). ROC analysis showed high AUC values in the derivation group and good accuracy in the test group. TR can be quantified from short-axis CMR images in agreement with echocardiography, while circumventing additional image acquisition