Preoperative and Intraoperative Predictors of Inotropic Support and Long-Term Outcome in Patients Having Coronary Artery Bypass Grafting

The prognostic value of preoperative symptoms, preoperative left ventricular function, and intraoperative factors as related to postoperative outcome in coronary artery bypass grafting is unclear. This study was performed to identify risk factors that could be used as markers to predict immediate and long-term outcome, knowledge of which might allow physicians to modify these factors to decrease the likelihood of an adverse outcome. We retrospectively evaluated preoperative factors (including age, sex, New York Heart Association NYHA classification of symptoms, ejection fraction EF, wall motion abnormalities, baseline left ventricular end-diastolic pressure LVEDP, postradiographic contrast infection LVEDP, change in LVEDP with contrast injection, cardiac enlargement, and collateral vessels) and intraoperative factors (duration of bypass and aortic cross-clamp time) in 128 patients. The need for inotropic drug support was used as a marker of immediate outcome. A 36-mo follow-up used death and the postoperative NYHA classification of symptoms as markers of long-term outcome. The various factors associated with the use of inotropes and immediate outcome were analyzed by logistic regression. The factors related to inotrope use (and presumed adverse short-term outcome) in order of decreasing significance were lower EF, older age, cardiac enlargement, female sex, and higher baseline and postcontrast LVEDP. Patients with EF s 55%, but also having wall motion abnormalities and LVEDP change ≥ 10 mm Hg, and all patients with EF ≥ 55% were more likely to require inotropic drug stimulation after cardiopulmonary bypass. Neither the change in LVEDP nor the presence of wall motion abnormalities independently predicted the need for postoperative inotropic support. Analysis of long-term outcome in 113 patients revealed an improvement in mean NYHA score from 2.8 ± 0.9 (mean ± SD) preoperatively to 1.6 ± 0.7 postoperatively. Those factors that predicted a worse long-term outcome (defined as higher postoperative NYHA scores or death) were higher preoperative NYHA scores, older age, female sex, and prolonged duration of cardiopulmonary bypass. Only 5 of 113 patients had died at the 36-mo follow-up, precluding statistical analysis of mortality. In contrast to randomized trials of oral inotropic agents in chronic congestive heart failure, in this study the perioperative use of inotropes (our marker of immediate outcome) was only marginally predictive of a less favorable long-term outcome.