Left ventricular end-diastolic pressure predicts survival in coronary artery bypass graft surgery patients

Abstract

Background: There is a known association between a depressed left ventricular ejection fraction (LVEF < 0.35) and increased mortality in patients undergoing coronary artery bypass graft (CABG) operations. Recent studies show that elevated preoperative LV end-diastolic pressure (LVEDP) is an independent predictor of operative death for patients undergoing CABG. Therefore, the purpose of this study was to define the long-term predictive value of elevated LVEDP in CABG and its relationship to LVEF.

Methods: Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH), a clinical data collection initiative capturing all patients undergoing isolated CABG in Alberta, Canada, was used to identify 6,735 consecutive patients who had LVEDP and LVEF data recorded by catheterization undergoing isolated CABG between 1996 and 2011. Patients were divided into four groups based on LVEF and LVEDP: group 1 (LVEF≥0.35, LVEDP<18 mm Hg), group 2 (LVEF<0.35, LVEDP<18 mm Hg), group 3 (LVEF≥0.35, LVEDP≥18 mm Hg), and group 4 (LVEF<0.35, LVEDP≥18 mm Hg).

Results: Patients with an LVEF>0.35 had improved long-term survival compared with patients with depressed LVEF (LVEF<0.35, p<0.001). In patients with a depressed LVEF, an elevated LVEDP was associated with decreased long-term survival (group 2 vs 4, p<0.001). Other significant independent predictors for death were age, chronic obstructive pulmonary disease, peripheral vascular disease, dialysis dependence, and congestive heart failure (p<0.001). Isolated elevated LVEDP was not an independent risk factor for long-term mortality.

Conclusions: In patients with a depressed LVEF, an elevated LVEDP is associated with poor long-term survival. These data support the added value of long-term prognostic value of LVEDP in patients with depressed LVEF undergoing CABG.