A hybrid approach for quantification of aortic valve stenosis using cardiac magnetic resonance imaging and echocardiography: comparison to right heart catheterization and standard echocardiography.

We replaced Doppler-derived stroke volume in the continuity equation (method A) by either right heart catheterization-derived stroke volume (method B) or cardiovascular magnetic resonance-derived stroke volume (method C) to calculate aortic valve area in 20 consecutive patients with moderate or severe aortic stenosis. Comparison of both hybrid methods (methods B and C) by Bland-Altman analysis showed a mean difference near zero, a spread within two standard deviations and very similar limits of agreement. More importantly, all patients were classified into the same category of severity by both methods.