New research has found that women are significantly less likely than men to undergo coronary artery bypass grafting (CABG) using guideline-recommended approaches, which can result in worse outcomes after surgery, according to a press release.

Investigators used the STS Adult Cardiac Surgery Database to identify adult patients who underwent first-time isolated CABG between 2011 and 2019. The database contains records of nearly all CABG procedures performed in the United States, which allowed the team to analyze detailed demographic, clinical, and procedural data from more than 1.2 million patients.

They analyzed the correlation between female sex and 3 different CABG surgical techniques that are recommended in official US and European Union guidelines: grafting of the left internal mammary artery (LIMA) to the left anterior descending (LAD) artery, complete revascularization, and multiarterial grafting. However, the results showed that women were 14% to 22% less likely than men to undergo procedures with these revascularization strategies.

“With these findings, we did in fact see less aggressive treatment strategies with women,” said investigator Oliver K. Jawitz, MD, of Duke University, in a press release. “It is clear that sex disparities exist in all aspects of care for patients with coronary artery disease (CAD), including diagnosis, referral for treatment, and now, in surgical approaches to CABG. We must ensure that female patients undergoing CABG are receiving evidence-based, guideline-concordant techniques.”

Although there are many reasons for the disparities, the investigators said the undertreatment of CAD in women largely stems from a failure to recognize key differences in cardiovascular risk factors and symptoms in women compared to men. Women are much more likely to experience atypical, subtler symptoms of heart disease, such as fatigue, abdominal pain, nausea, vomiting, indigestion, and back pain. Some women do not even feel the obvious chest pain and pressure that are characteristic of CAD.

Women also have their own set of risk factors, including relatively high testosterone levels prior to menopause, increased hypertension during menopause, and higher levels of stress and depression.

Jawitz also noted that women’s health has historically been focused on mother and child issues, as well as early diagnosis and treatment of breast cancer. These conversations need to include a stronger emphasis on cardiovascular risk factors and interventions. Doing so is vital to successfully tackling heart disease, which is the leading cause of death among women in the United States, according to Jawitz.

Furthermore, women tend to have a longer time between symptom onset to diagnosis and from diagnosis to medical intervention, according to the study. Each of these delays allows the disease to worsen and increases the risk for poor surgical outcomes. When women are finally referred for bypass surgery, they continue to be disadvantaged, since they often do not receive any of the 3 CABG surgical techniques that the investigators analyzed.

“Delayed diagnosis of CAD in women leads to late initiation of key behavioral and pharmacologic interventions for minimizing heart disease risk, as well as delayed referral for invasive diagnostic and therapeutic procedures, including surgical revascularization with CABG,” Jawitz said in the press release. “This often means that by the time female patients undergo these procedures, they have more severe disease than males, as well as a greater number of comorbidities, which leads to worse outcomes.”

The investigators also noted that women remain grossly underrepresented in some clinical trials. According to a separate analysis of research data, less than 40% of all people enrolled in cardiovascular clinical trials from 2010 to 2017 were women. Lack of knowledge is often cited as a reason for these persistent health disparities, according to the study authors.

Moving forward, the authors said guidelines must be developed that reflect the important differences between men and women in CAD manifestation. Developing these guidelines, however, will require increased representation of female patients in clinical trials of cardiovascular therapies.

REFERENCE
Women undergo less aggressive open heart surgery, experience worse outcomes than men [news release]. EurekAlert; January 30, 2021. https://sciencesources.eurekalert.org/pub_releases/2021-01/tsot-wul012821.php. Accessed February 1, 2021.