Value of the regurgitant volume to end diastolic volume ratio to predict the regression of left ventricular dimensions after valve replacement in aortic insufficiency

The aim of this study was to assess the value of regurgitant stroke volume (RSV) to end-diastolic volume (EDV) ratio to predict the regression of left ventricular (LV) dimensions after uncomplicated valve replacement in 34 patients with severe pure aortic insufficiency. The RSV/EDV ratio was measured by contrast ventriculography and thermodilution techniques. LV end-diastolic diameter (EDD) was measured pre- and postoperatively by M-mode echocardiography (at a median interval of 3.3 years after valve replacement). LV/EDD decreased from 74 +/- 8 mm to 54 +/- 11 mm (P less than 0.001). Eleven patients had a persistent postoperative LV enlargement (median EDD 65 mm, range 56-100 mm) while, in 23 patients, EDD became normal (median 49 mm, range 40-55 mm). During follow-up, one patient with LV enlargement died of congestive heart failure. Preoperative RSV/EDV ratio was significantly higher in patients with normal postoperative EDD as compared to those with persistent LV enlargement (0.32 +/- 0.06 vs. 0.24 +/- 0.07, P less than 0.005). The best cutoff point of RSV/EDV to predict the normalization of LV dimensions was 0.28. Postoperative EDD remained abnormal in eight out of 16 patients (50%) with RSV/EDV ratio less than 0.29, while it remained enlarged in only three out of 18 patients (17%) with a preoperative RV/EDV ratio greater than 0.28. The other usual preoperative catheterization and echocardiographic variables were equally or less predictive than RSV/EDV ratio. In conclusion, despite the limitations due to the use of different techniques, we confirmed that the RSV/EDV ratio is a potentially useful variable for the assessment of the proper timing of valve replacement in patients with severe isolated aortic insufficiency.