Fractional shortening-velocity ratio for assessment of aortic stenosis severity in patients with systolic dysfunction.

BACKGROUND

In the study of severity of aortic stenosis many different methods derived from transthoracic echocardiography are used. Their principal limitations are left ventricular dysfunction and calcified aortic valve. The objective of this study was to assess the utility of a described echocardiographic index: the fractional shortening-velocity ratio (FSVR=FS/4Vmax2) in those patients with left ventricular systolic dysfunction.

METHODS

We studied 72 patients with aortic stenosis and aortic valvular area (AVA)< or =2 cm2. AVA was assessed by the Gorlin equation. Left ventricular systolic dysfunction was defined by FS< or =29%. Using receiver operating characteristic curves analysis to test the predictive discrimination of patients with and without critical aortic stenosis, we studied the best FSVR value to assess aortic stenosis severity.

RESULTS

We found a significant linear correlation between AVA and FSVR (r=0.59; P<0.001). A value of FSVR < or =0.78 allowed the identification of patients with AVA< or =0.8 cm2 with good sensitivity and specificity (sensitivity: 94.5%; specificity: 60%; positive predictive value: 90% and negative predictive value: 75%). In our population, 22 patients (32%) showed a systolic dysfunction. The correlation AVA-FSVR was also significant in this group (r=0.68; P<0.001) and it may be even better than in the total group. However, the FSVR with the best sensitivity-specificity relation was different to the value used in the global group. A FSVR value <0.65 showed the best sensitivity-specificity relation in identifying patients with severe aortic stenosis (sensitivity: 100% and specificity: 56%).

CONCLUSION

The FSVR is a very simple and noninvasive index. It allows identification of patients with severe aortic stenosis with excellent sensitivity and good specificity. It may be useful in the evaluation of patients with aortic stenosis and left ventricular dysfunction, although, there is not an accepted FSVR value with the best-combined sensitivity-specificity, to identify a critical aortic stenosis.