Worse CABG Outcomes in Women Haven’t Budged in Over a Decade: STS

Compared with men, women undergoing CABG are at greater risk for operative mortality and morbidity, with no appreciable change in that disparity over the last decade, according to a study of more than 1.2 million patients.

Despite well-documented evidence that women present differently than men, including later in the disease course and with atypical symptoms, the diagnostic flowchart of CAD is heavily biased toward presentation in men, as are recommendations for revascularization, Mario Gaudino, MD, PhD (Weill Cornell Medicine, New York, NY), told TCTMD.

“One clear path to improvement is an earlier diagnosis with diagnostic criteria that are more tailored to women, not only to men,” he added.

Consistent with prior research, Gaudino and colleagues’ study, published recently in JAMA Surgery, found that women were more likely than men to have single- or double-vessel disease rather than triple-vessel or chronic total occlusion (CTO), yet their operative mortality (2.8% vs 1.7%) and the composite of operative mortality and morbidity (22.9% vs 16.7%; P < 0.001 for both comparisons) were still higher.

According to Gaudino, even the concept of “atypical” is a stumbling block because it suggests that women’s CV health is somehow unusual, rather than simply being different in comparison to men.

The study analyzed outcomes of 1,297,204 patients (24.5% women) who underwent primary isolated CABG between 2011 and mid-2020 and were enrolled in the Adult Cardiac Surgery Database of the Society of Thoracic Surgeons (STS).

Compared with men, women were about 2 years older and more likely to have hypertension, diabetes, chronic lung disease, cerebrovascular disease, and peripheral vascular disease. Women also were more likely to require urgent CABG and to be symptomatic, with the most common presentations being unstable angina (36.1%) and NSTEMI (30.9%).

Although there were variations by year in operative mortality, the rates in women outpaced men at every time point, being at their peak in 2020 and at their lowest in 2013. The findings were similar for the composite of operative mortality and morbidity, peaking in 2011 and at its lowest level in 2016.

When the investigators estimated the year-specific risk attributable to female sex, the composite of operative mortality and morbidity was 1.08 in 2011 and 2020; 1.09 (highest) in 2013 and 2019; and 1.02 (lowest) in 2012 and 2015 (1.02), with no significant change over the study period (P for trend = 0.71).

A Message About and for Women

Gaudino said he believes the stagnant numbers on top of similar patterns seen for women after PCI, and data showing that the CABG surgeries themselves are different in women, send an important message.

“I think there is in the cardiology community this sense that because of a general progressive improvement in patient outcomes . . . that this problem is just going away on its own,” he commented. “Our data show that is not happening.”

I think there is in the cardiology community this sense that because of a general progressive improvement in patient outcomes . . . that this problem is just going away on its own. Mario Gaudino

As for what needs to happen, Gaudino said repeated calls for enrolling more women in clinical trials isn’t the answer.

“We need to do clinical trials in women—dedicated trials. That's the only way to generate the critical information that will inform everything. From that we will learn how to do better diagnoses, better PCI, better surgery,” he said, adding that most trials dedicated to women undergoing PCI or CABG have been relatively small.

“We know that women have more microvascular disease and so the diagnostic testing before surgery should be different in women. We probably should be routinely assessing the microcirculation [because] if a woman has disease that is mostly microvascular, she's not likely to benefit from surgery,” Gaudino noted. “We need to really pay more attention and stop assuming we know what works.”