[Dobutamine infusion test for predicting the postoperative recovery of left ventricular function in patients with...

In order to predict the postoperative recovery of left ventricular (LV) function after valve replacement, dobutamine (DOB) infusion tests were performed on 21 patients with chronic aortic regurgitation (AR). As a predictor of the LV functional reserve. delta mVcf, calculated from the difference between the mVcf in echocardiographs before and after DOB infusion, was used. According to the values of delta mVcf, patients were classified into two groups. The good-response group consisted of 15 patients with delta mVcf greater than or equal to 0.45 cir/sec, and the poor-response group consisted of 6 patients with delta mVcf less than 0.45 cir/sec. Comparison of the early postoperative values in these two groups disclosed that the LV end-systolic dimensions (LVDs) and the %fractional shortening (%FS) improved in the good-response group, whereas in the poor-response group, the LVDs remained above 40 mm and the %FS, below 28% in the early postoperative period. A significant correlation was found between the preoperative delta mVcf and early postoperative %FS in both groups. The value of delta mVcf improved postoperatively, both in the good-response group and in the poor-response group; the %FS increased in the poor-response group late postoperatively. In patients whose delta mVcf did not improve in the postoperative DOB infusion test, the %FS remained depressed throughout the follow-up periods. Thus, the postoperative delta mVcf showed a significant correlation with the late postoperative %FS. In conclusion, DOB infusion tests were found to be an excellent indicator for estimating the amount and time course of improvement of LV function after surgery.