In-Hospital Mortality Higher When Female CABG Patients Have Male Surgeons

LISBON, Portugal—Women undergoing CABG surgery seem to have a higher rate of in-hospital mortality if they are treated by a male versus female surgeon, according to a single-center analysis from the United Kingdom. Yet the same could not be said about male patients treated by female surgeons or patients treated by surgeons of the same gender.

While the data as they stand are hypothesis-generating, they show trends consistent with larger analyses looking at all surgeries from the United States and Canada, and they are in line with similar studies on acute MI.

“These are really interesting findings which seem to follow a pattern, even in much larger studies, and something that we have to tease down as to what may be responsible,” said Indu Deglurkar, MBBS (University Hospital of Wales, Cardiff), who presented the data here Friday at the European Association for Cardio-Thoracic Surgery 2024 meeting during a session on unresolved questions in CABG.

“If there is something correctable that we can do to improve female outcomes, then we should do it,” she told TCTMD. “But that can only come with detailed analysis.”

Male Surgeons, Female Patients

For the analysis, Deglurkar looked at all 3,317 isolated CABG surgeries (mean patient age 67 years; mean logistic EuroSCORE 6.41) done at her institution between April 2010 and March 2023. The cases were grouped by self-reported gender:

• Male patient and male surgeon (n = 2,181)
• Male patient and female surgeon (n = 567)
• Female patient and male surgeon (n = 460)
• Female patient and female surgeon (n = 109)

Overall, 28 patients died in the hospital. When stratified by groups, nine women (2.0%) treated by a male surgeon died compared with 0.7% of men who had a male surgeon, 0.3% of men who had a female surgeon, and 0.9% of women who had a female surgeon (P = 0.043 for interaction). However, this pattern was not seen when the procedures were broken down into elective, urgent, and emergency cases. There was also no significant interaction by gender concordance overall or by surgeon gender.

Deglurkar and colleagues found no difference in secondary outcomes including any postoperative complications, reoperation for bleeding, deep sternal wound infection, stroke, and renal impairment by group, gender concordance, or surgeon gender.

The study is subject to several limitations, including low numbers of the primary outcome and the involvement of only one female surgeon, as well as the lack of information on the potential effects of other members of the care team, Deglurkar acknowledged.

‘Some Underappreciated Phenomena’

“There has been a lot said about patient and surgeon sociocultural aspects, structural sexism, unconscious bias, and potential communication styles based on surgeon and patient gender concordance or nonconcordance that could potentially affect the decision-making by referring physicians for elective cases,” she said. “But if our findings were actually causal, these results suggest that increasing gender diversity in the surgeon workforce has the potential to improve the quality of surgeon care and patient outcomes.”

Deglurkar said she would be pursuing a larger study encompassing the entire United Kingdom to look at the effects of patient-surgeon gender concordance on CABG outcomes. “I think there [are] some underappreciated phenomena,” she said.

“Patients can't always choose their surgeons. But when you have data that is lacking and when you have publications like these, there will be concerns by female patients who are undergoing surgery,” Deglurkar stressed. “What is definitely the truth in all these discussions is that there is an eminent paucity of female surgeons globally.”

There is an eminent paucity of female surgeons globally. Indu Deglurkar

Session co-chair Jennifer Lawton, MD (Johns Hopkins School of Medicine, Baltimore, MD), estimated that 5-7% of US cardiothoracic surgeons are female, while Deglurkar said that figure is around 9-10% in the UK.

Questioning the mechanism at play, Stephen Fremes, MD (University of Toronto, Canada), who also served as session co-chair, asked whether gender is the only driver or if age and racial/ethnic concordance might also be contributing.

Deglurkar said this remains a question that needs “deep reflection,” but noted that “if it was a discordance issue, then when female surgeons are operating on male patients, there should be some discordance. That doesn't seem to show up.”

What also needs further thought is why female patients undergoing CABG consistently have higher short-term mortality compared with male patients. “We know that women are less likely to receive arterial grafts than men, at least in the US, and they're also less likely to get complete revascularization,” she said. “But those affect long-term outcomes. Maybe we're missing something in the short term.”

Notably, Deglurkar warned against making statements like: “female surgeons are much better than male surgeons, or any nonsensical judgement.”

“I think a lot of things are needed before you can make interpretations completely pertaining to the gender of the surgeon or the patient,” she stressed.

In the meantime, Lawton made a suggestion to help reduce some potential gender-based bias in cardiac surgery. “Perhaps in a heart team discussion, you may discuss a patient as a 55-year-old patient and see what the consensus of treatment is, rather than saying woman [or] man,” she said.

Audience member Diana Reser, MD, PhD (HerzKlinik Hirslanden, Zurich, Switzerland), agreed the impact of gender concordance is “a very hot topic.” Still, “it's really important not to fight against each other—male and female surgeons or doctors,” she cautioned.