Coronary bypass grafts fail more frequently in women than in men

An international study in which MedUni Vienna played a key role has shown that women are more likely to experience bypass graft failure after coronary bypass surgery than men, which increases their risk of heart attack. The research recently published in the prestigious "Journal of the American College of Cardiology" is the most comprehensive scientific evaluation of bypass graft failure in women to date and emphasises the need for sex-specific treatment measures.

Data from 4,414 patients, including 777 women, from seven clinical trials were analysed by an international research team led by principal investigator Mario Gaudino from Weill Cornell Medicine, New York, and first author Sigrid Sandner from MedUni Vienna’s Department of Cardiac Surgery. The results show that women have poorer long-term results and a higher risk of complications following coronary artery bypass grafting (CABG) compared to men. This includes higher rates of bypass graft failure, especially when leg veins are used to bypass vascular occlusions or stenoses. "Better results are achieved with arteries harvested from the arm (radial arteries), but this method is used less frequently in women than in men," Sigrid Sandner points out. In addition, women were found to have a greater need for repeat interventions to improve myocardial perfusion and an increased risk of heart attack and death.

Women underrepresented in studies

"The causes of the sex difference after CABG are not sufficiently clear because women are underrepresented in the relevant studies," reports Sigrid Sandner. However, the results show that the reasons for this are not exclusively due to graft failure, but are influenced by a variety of additional factors. The fact that cardiovascular diseases are still diagnosed later in women and are often more advanced at the time of their bypass operation than in men is one of the factors. As the analyses of the patient data also showed, arterial bypasses are used less frequently in women than in men, but venous bypasses, which have poorer patency rates, are used more frequently. In addition, women often receive less comprehensive follow-up care after coronary bypass surgery, which can also contribute to the poorer long-term results.

"Our findings highlight the need to develop sex-specific approaches in the medical care of coronary bypass patients. In particular, we need to take measures to increase the patency rate of bypass grafts in women," emphasises Sigrid Sandner. Further research is also needed to identify the underlying causes of the poorer treatment results in women and to be able to take targeted measures.

Publication: Journal of the American College of Cardiology

Coronary Artery Bypass Graft Failure in Women: Incidence and Clinical Implications
Sigrid Sandner, Björn Redfors, Kevin R. An, Lamia Harik, Rachel Heise, Antonino Di Franco, Stephen E. Fremes, David L. Hare, Alexander Kulik, Andre Lamy, Joyce Peper, Marc Ruel, Jurrien M. ten Berg, Laura M. Willemsen, Qiang Zhao, Yunpeng Zhu, Daniel M. Wojdyla, Deepak L. Bhatt, John H. Alexander and Mario Gaudino
DOI: 10.1016/j.jacc.2024.04.046