Coronary artery bypass grafting in patients with severe left ventricular dysfunction: predictive significance of left ventricular diastolic filling pattern.

Abstract

The aim of our study was to evaluate the influence of left ventricular (LV) diastolic filling impairment on postoperative results in patients (pts) with low LV ejection fraction (EF) (<35%) undergoing coronary artery bypass grafting (CABG). The study covered 56 patients (mean age 58.9 +/- 17.1 years). Two dimensional Doppler echocardiographic investigations were performed pre- and 10-14 days post-CABG. Patients were divided into three groups according to the LV diastolic filling. Early postoperative mortality rate (including perioperative period and 2 weeks after surgery) was highest in the restriction group (33%) vs. pseudonormalization (12.5%) vs. impaired relaxation (13.6%). Postoperative cardiovascular complications rate was highest also in the restriction group, 55.5%, and did not differ between pseudonormalization (25%) and impaired relaxation group (27.2%). Logistic regression analysis showed that restrictive LV filling pattern, early diastolic filling deceleration time and LV end-diastolic diameter independently influence perioperative mortality. In the early postoperative period mean LV wall motion score (WMS) did not improve in 8/19 (42%), 6/14 (43%) and 8/12 (67%) patients, respectively, in the impaired relaxation, pseudonormalization and restriction group. In patients with severe LV dysfunction undergoing CABG, impaired relaxation and pseudonormal pattern of LV diastolic filling correlated with postoperative improvement in LV regional contraction, while restrictive pattern correlated with high early postoperative mortality, morbidity and minimal improvement in LV systolic function. Restrictive LV filling pattern, early diastolic filling deceleration time and LV end-diastolic diameter were found to be independent predictors of perioperative mortality.