Temporal Trends, Clinical Characteristics and Outcomes of Emergent Coronary Artery Bypass Grafting for Acute Myocardial Infarction in the United States.

Background There are limited contemporary data on the use of emergent coronary artery bypass grafting (CABG) in acute myocardial infarction (AMI). Methods and Results Adult (>18 years) AMI admissions were identified using the National Inpatient Sample (2000-2017) and classified by tertiles of admission year. Outcomes of interest included temporal trends of CABG use, age-, sex-, and race-stratified trends in CABG use, in-hospital mortality, hospitalization costs, and hospital length of stay. Of the 11,622,528 AMI admissions, emergent CABG was performed in 1,071,156 (9.2%). CABG utilization decreased overall (10.5% [2000] to 8.7% [2017]; adjusted odds ratio [OR] 0.98 [95% confidence interval {CI} 0.98-0.98]; p<0.001), in ST-segment-elevation AMI (STEMI) (10.2% [2000] to 5.2% [2017]; adjusted OR 0.95 [95% CI 0.95-0.95]; p<0.001) and non-ST-segment-elevation AMI (NSTEMI) (10.8% [2000] to 10.0% [2017]; adjusted OR 0.99 [95% CI 0.99-0.99]; p<0.001), with consistent age, sex and race trends. In 2012-2017, compared to 2000-2005, admissions receiving emergent CABG were more likely to have NSTEMI (80.5% vs. 56.1%), higher rates of non-cardiac multiorgan failure (26.1% vs. 8.4%), cardiogenic shock (11.5% vs. 6.4%) and use of mechanical circulatory support (19.8% vs. 18.7%). In-hospital mortality in CABG admissions decreased from 5.3% [2000] to 3.6% [2017]; adjusted OR 0.89 [95% CI 0.88-0.89]; p<0.001 in the overall cohort, with similar temporal trends in STEMI and NSTEMI. An increase in lengths of hospital stay and hospitalization costs was seen over time. Conclusions Utilization of CABG has decreased substantially in AMI admissions, especially in STEMI. Despite an increase in acuity and multi-organ failure, in-hospital mortality consistently decreased this population.