Commentary: Off-pump and on point: Sex-stratifying multiple arterial grafting.

Central MessageOff-pump coronary artery bypass grafting does not appear to influence all-cause mortality with multiple arterial grafting, but more work is needed to explore the risk of major adverse events in women.See Article page XXX. Off-pump coronary artery bypass grafting does not appear to influence all-cause mortality with multiple arterial grafting, but more work is needed to explore the risk of major adverse events in women. See Article page XXX. There has been growing interest in the use of multiple arterial grafting (MAG) and off-pump coronary artery bypass grafting (CABG). Although both procedures have shown promise in improving outcomes, the evidence has been mixed, largely due to differences in patient characteristics, surgery volumes, and surgeon experience. Cardiac surgery outcomes commonly differ between men and women, underscoring the need for sex-stratified analyses to better understand the influence of these procedures on different patient populations.1Vervoort D. Chung J.C.Y. Ouzounian M. No one-size-fits-all: the need for sex-based analysis and management in cardiac surgery.Ann Thorac Surg. 2022; 114: 1671https://doi.org/10.1016/j.athoracsur.2022.03.078Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar Rubens and colleagues2Rubens F.D. Fremes S.E. Grubic N. Fergusson D. Taljaard M. van Walraven C. Outcomes following coronary artery bypass grafting with multiple arterial grafting by pump status in men and women.J Thorac Cardiovasc Surg. 2023; (XXX:XXX)Abstract Full Text Full Text PDF Scopus (1) Google Scholar present a retrospective, population-based analysis of isolated CABG with MAG (16,209 men and 2989 women) stratified by pump status using health administrative data from across Ontario, Canada. At a median follow-up of 5.0 years (interquartile range, 2.7-8.0 years), all-cause mortality was not influenced by pump status (hazard ratio in women: 1.25; 95% CI, 0.83-1.88 and men: 1.08; 95% CI, 0.85-1.37). However, there was an increased risk of major adverse cardiovascular and cerebrovascular events (MACCE) in women undergoing off-pump MAG-CABG (hazard ratio, 1.45; 95% CI, 1.04-2.03), suggesting the need for caution in the concomitant use of off-pump approaches and MAG. The authors should be applauded for their important and well-conducted study using a comprehensive data source and applying a rigorous methodology with sensitivity analyses accounting for variation in institutional volumes. Stratification of analyses by sex and pump status enables a more nuanced insight into tailoring the best possible coronary revascularization treatment to different patients. Some limitations and questions remain. The definition of MACCE employed by the authors did not include death, which may hinder comparisons with findings from other studies. Additionally, administrative data carry inherent limitations, including potential misclassification of MAG and pump status and the absence of more granular procedural details. Although sensitivity analyses were performed to evaluate whether results were consistent in high-volume centers only, the study was unable to assess the variability in experience among individual surgeons who performed the procedures, which may have a more pronounced effect than hospital volume.3Birkmeyer J.D. Stukel T.A. Siewers A.E. Goodney P.P. Wennberg D.E. Lucas F.L. Surgeon volume and operative mortality in the United States.N Engl J Med. 2003; 349: 2117-2127Crossref PubMed Scopus (2630) Google Scholar Lastly, although results were sex-stratified, the authors were unable to account for other sociodemographic variables that are known to influence cardiac surgical outcomes, including but not limited to race, ethnicity, and indigeneity.4Vervoort D. Kimmaliardjuk D.M. Ross H.J. Fremes S.E. Ouzounian M. Mashford-Pringle A. Access to cardiovascular care for Indigenous Peoples in Canada: a rapid review.CJC Open. 2022; 4: 782-791https://doi.org/10.1016/j.cjco.2022.05.010Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar,5Benedetto U. Kamel M.K. Khan F.M. Angelini G.D. Caputo M. Girardi L.N. et al.Are racial differences in hospital mortality after coronary artery bypass graft surgery real? A risk-adjusted meta-analysis.J Thorac Cardiovasc Surg. 2019; 157: 2216-2225.e4Abstract Full Text Full Text PDF PubMed Scopus (22) Google Scholar Investigations to date have primarily been conducted on cohorts with a disproportionate number of men. Sex-stratified research is essential for the development of interventions that consider the specific needs and challenges faced by women. Despite documented sex-based disparities in cardiac surgical outcomes, women continue to be significantly underrepresented in trials.6Preventza O. Critsinelis A. Simpson K. Olive J.K. LeMaire S.A. Cornwell L.D. et al.Sex, racial, and ethnic disparities in U.S. Cardiovascular trials in more than 230,000 patients.Ann Thorac Surg. 2021; 112: 726-735Abstract Full Text Full Text PDF PubMed Scopus (28) Google Scholar,7Gaudino M. Di Mauro M. Fremes S.E. Di Franco A. Representation of women in randomized trials in cardiac surgery: a meta-analysis.J Am Heart Assoc. 2021; 10: e020513Crossref PubMed Scopus (8) Google Scholar To date, investigations examining the influence of MAG on the outcomes of CABG in women have produced inconsistent findings, ranging from improved survival and freedom from MACCE8Tam D.Y. Rocha R.V. Fang J. Ouzounian M. Chikwe J. Lawton J. et al.Multiple arterial coronary bypass grafting is associated with greater survival in women.Heart. 2021; 107: 888-894Crossref PubMed Scopus (12) Google Scholar to moderately improved results that were restricted to small studies9Robinson N.B. Lia H. Rahouma M. Audisio K. Soletti Jr., G. Demetres M. et al.Coronary artery bypass with single versus multiple arterial grafts in women: a meta-analysis.J Thorac Cardiovasc Surg. August 10, 2021; ([Epub ahead of print]. https://doi.org/10.1016/j.jtcvs.2021.07.047)Google Scholar to a lack of benefit, possibly due to a higher proportion of women being considered high-risk.10Gaudino M. Samadashvili Z. Hameed I. Chikwe J. Girardi L.N. Hannan E.L. Differences in long-term outcomes after coronary artery bypass grafting using single versus multiple arterial grafts and the association with sex.JAMA Cardiol. 2020; 6: 401Crossref PubMed Scopus (23) Google Scholar The current study adds to this array of findings. These mixed results underscore the need for additional research to clarify the benefits and limitations of MAG, particularly for specific patient populations. Beyond sex, there also remain other factors that warrant further investigation because a multitude of patient characteristics have been shown to influence outcomes following CABG, including race, ethnicity, indigeneity, and socioeconomic status, which need to be elucidated to improve long-term outcomes and patient-centeredness of CABG.4Vervoort D. Kimmaliardjuk D.M. Ross H.J. Fremes S.E. Ouzounian M. Mashford-Pringle A. Access to cardiovascular care for Indigenous Peoples in Canada: a rapid review.CJC Open. 2022; 4: 782-791https://doi.org/10.1016/j.cjco.2022.05.010Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar,5Benedetto U. Kamel M.K. Khan F.M. Angelini G.D. Caputo M. Girardi L.N. et al.Are racial differences in hospital mortality after coronary artery bypass graft surgery real? A risk-adjusted meta-analysis.J Thorac Cardiovasc Surg. 2019; 157: 2216-2225.e4Abstract Full Text Full Text PDF PubMed Scopus (22) Google Scholar The study by Rubens and colleagues2Rubens F.D. Fremes S.E. Grubic N. Fergusson D. Taljaard M. van Walraven C. Outcomes following coronary artery bypass grafting with multiple arterial grafting by pump status in men and women.J Thorac Cardiovasc Surg. 2023; (XXX:XXX)Abstract Full Text Full Text PDF Scopus (1) Google Scholar supports the use of MAG regardless of pump status. However, the study also highlights the need to explore the association between off-pump MAG and an increased risk of MACCE in women. Further research will be needed to ensure that we remain on point, even when off-pump, to ensure that all patients receive the best possible care. Outcomes following coronary artery bypass grafting with multiple arterial grafting by pump status in men and womenThe Journal of Thoracic and Cardiovascular SurgeryPreviewMultiple arterial grafting (MAG) and off-pump surgery are strategies proposed to improve outcomes with coronary artery bypass grafting (CABG). This study was conducted to determine the impact of off-pump surgery on outcomes after CABG with MAG in men and women. Full-Text PDF