CMR-derived TAPSE measurement: a semi-quantitative method of right ventricular function assessment in patients with hypertrophic cardiomyopathy

Aim To compare cardiovascular magnetic resonance (CMR)derived right ventricular fractional shortening (RVFS), tricuspid annular plane systolic excursion with a reference point within the right ventricular apex (TAPSE(in)) and with one outside the ventricle (TAPSE(out)) with the standard volumetric approach in patients with hypertrophic cardiomyopathy (HCM). Methods and results 105 patients with HCM and 20 healthy subjects underwent CMR. In patients with HCM, TAPSEin (r=0.31, p=0.001) and RVFS (r=0.35, p=0.0002) revealed a significant but weak correlation with right ventricular ejection fraction (RVEF), whereas TAPSEout (r=0.57, p<0.0001) showed a moderate correlation with RVEF. The ability to predict RVEF<45 % in HCM patients was best for TAPSEout. In patients with hypertrophic obstructive cardiomyopathy (HOCM), RVEF showed a significant but weak correlation with TAPSEout (r=0.36, p=0.02) and no correlation with TAPSEin (r=0.05, p=0.07) and RVFS (r=0.02, p=0.2). In patients with hypertrophic non-obstructive cardiomyopathy (HNCM), there was a moderate correlation between RVEF and TAPSEout (r=0.57, p<0.0001) and a weak correlation with TAPSEin (r=0.39, p=0.001) and RVFS (r=0.38, p=0.002). In the 20 healthy controls, there was a strong correlation between RVEF and all semi-quantitative measurements. Conclusion CMR-derived TAPSEin is not suitable to determine right ventricular function in HCM patients. TAPSEout showed a good correlation with RVEF in HNCM patients but only a weak correlation in HOCM patients. TAPSEout might be used for screening but the detection of subtle changes in RV function requires the 3D volumetric approach.