Abstract 2292: Doppler-Derived Mitral Regurgitation Volume as a Predictor of Postoperative Left Ventricular Dysfunction after Mitral Valve Repair in Patients with Preoperatively Normal Left Ventricular Function
We anecdotally encounter postoperative left ventricular (LV) dysfunction after surgical correction for mitral regurgitation (MR), despite preoperative ejection fraction (EF) and end-systolic dimension (LVDs) meeting the current guidelines. We sought to clarify if Doppler-derived MR volume could be predictive of “unexpected” LV dysfunction after mitral valve (MV) repair. We retrospectively analyzed pre- and post-operative (median 4th postoperative day) echocardiograms of consecutive 161 patients (104 men, age 57±13 years) who underwent MV repair for pure and isolated MR, and had preoperatively normal LV function, defined as both EF >60% and LVDs <40 mm according to the current class I indication for surgical MV correction. Quantification of MR volume was performed by the quantitative Doppler and/or proximal isovelocity surface area method. Postoperative LV dysfunction, defined as EF <50%, was noted in 32 patients (20%). In patients with postoperative LV dysfunction, preoperative MR volume was larger than those without [95 (interquartile range 85 to 101) vs. 62 (52 to 73) mL, P<0.001], as well as LVDs and LV end-diastolic and left atrial dimension. However, preoperative EF was not significantly different between these 2 groups [67 (63 to 73) vs. 69 (65 to 74) %, P=0.079]. Echocardiographic independent predictor of LV dysfunction was MR volume, as well as LVDs (TABLE⇓). Using optimal cutoff value of 80 mL for MR volume combined with that of 35 mm for LVDs, we could predict postoperative LV dysfunction more accurately than using the value for only LVDs (correct classification rate of 0.87, 95% confidence interval 0.82 to 0.92 vs. those of 0.70, 0.63 to 0.77, P<0.001). Doppler-derived MR volume could be a powerful predictor of unexpected postoperative LV dysfunction. Earlier indication of MV repair than the current guidelines may prevent postoperative LV dysfunction in patients with LVDs >35 mm and MR volume >80 mL.