MITRAL TO AORTIC VELOCITY TIME INTEGRAL RATIO - A NONGEOMETRIC PULSED-DOPPLER REGURGITANT INDEX IN ISOLATED PURE MITRAL REGURGITATION

To determine the clinical value of a simple and non-geometric pulsed D oppler regurgitant index, namely the mitral to aortic velocity-time in tegral (VTI) ratio in the semiquantiative assessment of severity of is olated pure mitral regurgitation (MR), 109 patients with isolated pure MR and sinus rhythm prospectively underwent Doppler echocardiography within 48 h of cardiac catheterization. The eccentricity of regurgitan t jets was assessed by Doppler colour flow imaging and the mitral and aortic VTI and its ratio were derived from the pulsed Doppler method. Angiographic grade of MR was evaluated in all patients with MR, but ha emodynamic regurgitant fraction was determined in only 91 patients. Fi fty patients in sinus rhythm and without valvular disease served as co ntrols.In the control group, the mitral VTI (16.2 +/- 2.5 cm) was lowe r than the aortic VTI (20.6 +/- 2.8 cm) (P<0.001), resulting in a mitr al to aortic VTI ratio of 0.79 +/- 0.08. In patients with MR, the mitr al VTI was significantly greater than the aortic VTI (23.1 +/- 6.8 vs 16.9 +/- 4.7 cm, P<0.001). There was a close relationship between the mitral to aortic VTI ratio and the angiographic grading of MR (n=109, r=0.74, P<0.001). A ratio greater-than-or-equal-to 1.3 classified pati ents with severe MR (grade III or IV) with a sensitivity of 87%, a spe cificity of 91%, and positive and negative predictive values of 93% an d 84%, respectively. In 91 patients with MR, the mitral to aortic VTI ratio correlated well with the regurgitant fraction (r=0.73, P<0.001). A ratio greater-than-or-equal-to 1.3 identified a regurgitant fractio n of greater-than-or-equal-to 40% with a sensitivity of 90%, a specifi city of 85%, and positive and negative predictive values of 91% and 82 %, respectively. The accuracy of the ratio for predicting severe MR wa s similar in patients with central and eccentric jets. In conclusion, pulsed Doppler-derived mitral to aortic VTI ratio may represent an eas ily measured regurgitant index for patients with isolated pure MR inde pendent of jet geometry.