Comparison of the Mitral Regurgitation Volume Derived From Transthoracic Echocardiography Between the HeartModel and Continuity Equation Methods in Patients With Severe Mitral Regurgitation

We compared the mitral regurgitation (MR) volume measured between 2

the 2D continuity equation transthoracic echocardiography (2D CE-TTE) and the 3D HeartModel transthoracic echocardiography (3D HM-TTE).

Thirty-five patients at a mean age of 53.31 years (SD=15.16) were enrolled. All the patients were diagnosed with severe MR via transesophageal echocardiography. For the comparison of the MR volumes yielded by the 2 methods, the Bland–Altman chart and linear regression analyses were conducted.

The Bland–Altman analysis showed a mean difference of −89.30 mL between the MR volume measurements of the 2 methods, and the linear regression resulted in a standardized coefficient β of −0.831 (P<0.001). Hence, the analysis showed a significant proportional bias between 2D CE-TTE and 3D HM-TTE.

Overall, we observed that 2D CE-TTE overestimated the MR volume measured by 3D HM-TTE by about 30%.