Abstract 5792: Comparison of Real Time Three Dimensional Echocardiography with Cardiac Magnetic Resonance for Right Ventricular Mass and Ejection Fraction Calculation in 80 Pulmonary Hypertensive Patients
Introduction: This study identifies accuracy and reproducibility of mass, volume and ejection fraction measurement, as measured with 3D echocardiography (3DE), and validated with CMR. We examined 80 patients with 3DE and CMR for volume and mass measurement. The aim of this study was to examine the agreement of the two imaging modalities.
Methods- Patients: 80 patients with pulmonary arterial hypertension (PH) (60 idiopathic disease, mean age 43.2 ± 19.2 years, 55 women) were examined with 3DE and CMR, within the same day. End-diastolic (EDV), end-systolic (ESV), stroke volume (SV) and ejection fraction (EF), were measured with disk summation method. Right ventricular mass (RVM) was estimated through the subtraction of endocardial from epicardial cast and the multiplication with myocardial density (1.055 g/dl). The same protocol was applied for both modalities. TOMTEC and View Forum(Philips) were employed for the measurement of values. Bland & Altman agreement analysis was used for the analysis of the results. A p value < 0.05 was considered significant. All measurements were performed independently by two observers and the mean value used.
Results: End-diastolic volumes and stroke volumes were underestimated, when compared to the CMR values (EDV3D : 185.2 ± 38.9 ml vs EDVCMR: 194 ± 46 ml). However, in PH patients, the two imaging modalities demonstrated a significant agreement for volumes and ejection fraction, with low bias and acceptable standard deviation (EDV 3D-CMR: r = 0.79, mean bias −6.4 ml, SD 29.3 ml, ESV 3D-CMR: r = 0.78, mean bias −4.56 ml, SD 25.8 ml, EF 3D-CMR: r = 0.67, mean bias 0.05%, SD 8.6%, RVM 3D-CMR: r = 0.68, mean bias −3.27g, SD 28g) and a good inter-observer reproducibility, between the two observers. CMR has lower variability of values, concerning reproducibility: (EF 3D: r = 0.77, p<0.01, mean bias 1.3%, SD 6.3%, CMR EF: r = 0.86, p<0.01, mean bias 1.3%, SD 5.4%, RVM 3D: r = 0.77, p<0.01, mean bias −16.8 g, SD 17.8 g, RVM CMR: r = 0.79, p<0.01, mean bias −6.9 g, SD 17.8 g).
Conclusion: Real time three dimensional echocardiography and cardiac MRI are two interchangeable modalities, with good agreement and reproducibility. 3DE can be employed as a bed side modality for mass and volume calculation.