Arterial Grafting Survival Benefit in End-Stage Renal Disease Patients Undergoing Coronary Arterial Bypass Grafting

C. Yang¹, T. Ogami², P. Wang³, J. Stevens⁴, Y. Kaku⁵, K. Takeda⁶, P. Kurlansky^7
1New York-Presbyterian/Columbia University Medical Center, New York, New York ²NYU Langone Health, New York, New York ³Center for Innovation and Outcomes Research, Columbia University Medical Center, New York, New York ⁴Division of Nephrology, Columbia University Medical Center, New York, New York ⁵Columbia University, Fort Lee, New Jersey ⁶Columbia University Medical Center, New York, New York ⁷Division of Cardiothoracic Surgery, Columbia University Irving Medical Center, New York, New York

Purpose: End-stage renal disease (ESRD) is associated with increased morbidity and mortality in patients undergoing CABG (1). It is unknown whether there is a survival benefit to use arterial grafting vs. saphenous vein graft (SVG) (2). This study compared survival for arterial vs. SVG grafting in patients with ESRD on dialysis.

Methods: Using the United States Renal Data System (USRDS), data were collected on all CABG patients, along with subsequent transplant status from 2015 to 2022. CABG graft patterns were divided as left internal mammary artery (LIMA) plus SVG grafting vs. SVG-only grafting and LIMA vs. multi-arterial grafting (MAG). Inverse probability of treatment weighting (IPTW) was used to adjust for baseline differences among four groups of patients: LIMA vs. SVG-only (non-transplanted), LIMA vs. SVG-only (transplanted), LIMA vs. MAG (non-transplanted), and LIMA vs. MAG (transplanted).

Results: In the total, unmatched cohorts there were 13,820 patients in LIMA, 505 patients in MAG, and 2,149 patients in SVG-only (See Table 1). There were numerous differences among the groups, however, after IPTW, these factors were well balanced within comparison groups. After matching, LIMA had lower in-hospital mortality compared to SVG-only patients in both the non-transplanted (8.7% vs. 12.0%, p< 0.001) and transplanted groups (3.0% vs. 6.1%, p=0.005). LIMA had comparable in-hospital mortality compared to MAG patients (8.5% vs. 8.4%, p=0.94 non-transplanted, and 2.8% vs. 0.9%, p=0.25, transplanted). In terms of long-term survival, LIMA grafting had a survival benefit compared to SVG-only in transplanted patients (p < 0.0001) and non-transplanted patients (p < 0.0001) in unmatched and matched cohorts (See Figure 1a, 1b, 1e, 1f). MAG has significant survival benefit compared to LIMA in transplanted patients (p=0.0032) but not in non-transplanted patients (p=0.28) in unmatched and matched cohorts (Figure 1c, 1d, 1g, 1h). Of note, whereas 5-year survival in transplanted LIMA patients was 70% compared to 78% in the transplanted MAG group, 5-year survival in non-transplanted cohorts was only 37% for LIMA and 37% for MAG.

Conclusion: Despite diminished life expectancy for patients with ESRD, there remains a survival benefit for arterial grafting in both transplanted and non-transplanted patients. The incremental benefit for MAG vs. LIMA is apparent only in those patients who receive subsequent transplant.

Identify the source of the funding for this research project: N/A