B. Khoraminejad1,2,3, S. Sakowitz1,2, T. Coaston1,2, S. Mallick1,2, E. Aguayo1,2, G. Porter1,2, E. Elkins1,2,4, P. Benharash1,2 1David Geffen School Of Medicine, University Of California At Los Angeles, Cardiovascular Outcomes Research Laboratories, Los Angeles, CA, USA 2David Geffen School Of Medicine, University Of California At Los Angeles, Department Of Surgery, Los Angeles, CA, USA 3Boston University, Boston, MA, USA 4Columbia University in the City of New York, New York, NY, USA
Introduction:
Limited prior work has considered outcomes following reoperative coronary artery bypass graft surgery (CABG). Using a contemporary national cohort, we assessed acute clinical and financial outcomes following reoperative CABG. We secondarily considered the impact of care at high case volume hospitals.
Methods:
The 2016-2021 Nationwide Readmissions Database (NRD) was queried to identify all adult (≥ 18 years) hospitalizations for elective isolated CABG. Patients who had previously received a CABG were categorized as the Reoperation cohort (others: Non-Reoperation). Hospital annual CABG volume was tabulated, with centers in the highest quartile considered high-volume centers (HVC). Multivariable regression models were developed to assess the independent association of Reoperation with clinical and financial outcomes.
Results:
Of an estimated 469,456 patients, 23,151 (4.9%) were classified as Reoperation. On average, the Reoperation cohort was older (70 vs 67, p<0.001), more commonly female (26.7 vs 21.7%, p<0.001), and of a higher Elixhauser comorbidity index (5 vs 4, p<0.001). Further, Reoperation more frequently had diabetes (48.2 vs 44.9%, p<0.001) and a history of smoking (54.3 vs 49.9%, p<0.001).
Following risk adjustment, and with Non-Reoperation as reference, Reoperation was linked with comparable likelihood of in-hospital mortality (AOR 0.87, 95% CI 0.74-1.03). Reoperation was also associated with greater odds of perioperative infection (AOR 1.72, 95% CI 1.60-1.85), thromboembolism (AOR 1.85, 95%CI 1.45-2.36), and stroke (AOR 1.35, 95% CI 1.12-1.64, Figure A). Additionally, Reoperation faced similar duration of hospitalization compared to Non-Reoperation (LOS, β -0.08, 95% CI -0.73-+0.58), but significantly greater per-patient costs (β +$9,845, 95% CI $8,888-$10,802). The groups were similar in likelihood of non-elective readmission within 30 days (AOR 1.01, 95% CI 0.94-1.09).
Considering the 291,985 patients treated at HVC, 12,754 (4.4%) were Reoperation. Following risk adjustment, Reoperation remained associated with greater odds of major morbidity (AOR 1.19, 95%CI 1.12-1.27). Reoperation was also linked with similar duration of hospitalization (β -0.61, 95% CI -1.37-+0.15), but increased per-patient hospitalization expenditures (β +$6,782, 95%CI $5,725-%7,837).
Conclusion:
Patients undergoing reoperative CABG demonstrated similar mortality, but greater likelihood of major complications and increased resource utilization, relative to those undergoing first-time revascularization. This delta in risk persisted even among patients treated at HVC. Further studies are needed to improve risk stratification and develop optimal perioperative care pathways for these patients.