Heart Surgery Long-Term Mortality Rate Higher for Women

By Anne Harding

September 03, 2019

NEW YORK (Reuters Health) - Women have worse long-term mortality after coronary-artery bypass grafting (CABG) and combined CABG/mitral-valve surgery, while mortality risk factors are different for men and women, according to new findings.

"Women with a history of (myocardial infarction) and diabetes, and men with a history of (chronic obstructive pulmonary disease) and depression, were high-risk groups in whom intensive long-term follow-up is warranted," Dr. Louise Y. Sun of the University of Ottawa in Canada told Reuters Health in an email.

Few studies have looked at the effect of sex on patients' long-term prognosis after heart surgery, Dr. Sun and her team note in the Journal of the American Heart Association, online August 23. They looked retrospectively at a cohort of more than 72,000 Ontario residents 40 and older who had undergone CABG with or without aortic-, mitral-, or tricuspid-valve surgery in 2008-2016.

One-quarter of the patients were women, and median follow-up lasted five years. Women were, on average, three years older than men.

Thirty-day mortality rates were 2.7% for women versus 1.6% for men (P<0.001), and ranged from 1.4% for isolated CABG to 7.5% for CABG plus multiple-valve surgery. Women were also significantly more likely to die within a year of surgery (6.2% vs. 4.1%) and during longer-term follow-up (19.0% vs. 14.8%).

Being female was associated with a higher mortality risk in a sensitivity analysis using inverse-probability-of-treatment weighting of the propensity score (hazard ratio, 1.10; 95% confidence interval, 1.05 to 1.16).

Age-standardized mortality rate (AMR) at 30 days for isolated CABG was 0.6 per 1,000 person years for women and 0.4 per 1,000 for men. Long-term AMR with CABG was 28.4 per 1,000 person years for women and 23.6 per 1000 person years for men (P<0.001).

AMR was also significantly higher in women undergoing CABG combined with mitral valve repair compared to men. In any procedure involving coronary revascularization, AMR was numerically higher for women.

"We found that women were more likely than men to have CABG during an acute cardiac admission, and were more likely than men to be hospitalized for heart failure before surgery," Dr. Sun noted.

"Women with cardiac disease often experience a delay in diagnosis and treatment, which leads to more advanced disease at the time of surgery," she added. "This may in fact be the case with women who have combined CABG/mitral valve surgery, whose mitral regurgitation were more likely to have resulted from an ischemic etiology and were therefore at a higher risk of dying."

She concluded: "Early disease recognition of acute cardiac disease presentation is key, especially in women."

SOURCE: https://bit.ly/349p5yJ

J Am Heart Assoc 2019.