Aortic regurgitation and left ventricle remodeling on cardiac magnetic resonance and transthoracic echocardiography

Background: Transthoracic echocardiography (TTE) is the first imaging modality used to assess aortic regurgitation (AR). However, it is not possible to provide precise quantification in all patients. Aim: Our aim was to compare TTE and cardiovascular magnetic resonance (CMR) measurements in grading AR and left ventricle (LV) remodeling. Methods: A total of 51 consecutive patients with AR in TTE (New York Heart Association I/II, 55%/38%) were enrolled into the study and 49 individuals (age, 57.1 [14]; 61% males) underwent a non-contrast CMR (2 patients excluded) obtained on 1.5 T system (GE Optima MR450w). Results: The comprehensive quantitative grading with AR volume (AR vol) and regurgitant fraction (RF) were measurable in TTE in 24 cases and showed an association with CMR parameters (AR vol: r = 0.75; P<0.001 and RF: r = 0.55; P<0.01). CMR revealed larger LV end-diastolic volumes (EDV) (185.5 [61] vs 158.4 [61] ml; P = 0.03) and a trend towards higher left ventricular ejection fraction (59% [8] vs 56% [8]; P = 0.08). The association of AR vol and LV EDV was stronger in CMR (r = 0.85; P <0.0001) compared to TTE (r = 0.6; P = 0.001). The inter-modality agreement ( TTE-CMR) in AR grading was low (kappa = 0.15), with highly concordant grading in mild AR (91%). Conclusions: CMR provides a comprehensive assessment of AR severity and LV remodeling with a weak or a moderate agreement with TTE.