8500 cardiac patients participated in a study conducted by St. Olav's Hospital in Trondheim. Illfoto: Thinkstock

Heart disease – more serious for women?

On average, women live longer than men. But for women with cardiovascular disease who undergo open-heart surgery, it’s different.

A study of 8500 heart surgery patients at St. Olavs Hospital shows that patients who underwent open-heart surgery lived as long, or longer than, the average Norwegian the first seven years after surgery. But among women, patient groups under 70 years of age and patients who underwent aortic valve replacement (AVR), relative mortality was higher after a few years.

“Undergoing cardiac surgery at a relatively ‘young’ age usually means that you suffer from severe cardiovascular disease. The lower long-term survival rate in younger patients and women may be due to a more aggressive disease,” says Tone Bull Enger, a physician and PhD candidate at NTNU’s Department of Laboratory Medicine, Children’s and Women’s Health.

Surgery survival is better in older patients

Among the elderly patients, the survival rate was just as high as in the general population. Cardiac surgery patients over 80 had very good results.

Bull Enger says this may well be because surgeons are selective when assessing whether a patient is a good candidate for surgery. “When operating on an 85-year-old, we’re talking about a seriously ill patient. What matters most for the operation are possible risk factors and overall health. Patients who are well-suited for surgery will generally be in better health overall compared with the national average for the age group,” she adds.

Enger suggests that age alone does not preclude surgery, but that it’s important to look at how the patient is functioning in daily life and at the overall disease picture and to consider these factors in the context of the particular operation. An overall assessment is always necessary.

Tone Bull Enger is a physician and a PhD candidate at the Department of Laboratory Medicine, Children's and Women's Health at NTNU.

Tone Bull Enger is a physician and a PhD candidate at the Department of Laboratory Medicine, Children’s and Women’s Health at NTNU.

Several procedures increase risk

The study shows that the survival rate among bypass patients was very good, but patients who underwent two or more procedures simultaneously had lower survival rates.

“It’s to be expected that more complicated procedures carry a higher risk,” says Bull Enger. “Cardiovascular disease is a chronic illness, and the key to reducing the risk of death is prevention. Measures to prevent further disease progression are highly standardized following bypass surgery. Several studies have also shown a positive effect from similar measures with other procedures, but with no set guidelines for follow-up, it’s more up to the individual doctor. Perhaps something could be gained by establishing firmer guidelines for other groups,” she says.

About the study

The study was based on 8564 patients who underwent open-heart surgery consecutively at St. Olavs Hospital in Trondheim, from 2000 through 2014. Observed survival over time was compared with expected survival in the general Norwegian population, matched on gender, age and calendar year.

The Cardiac Surgery Outcome Study (CaSOS) is a collaboration between NTNU and St. Olavs Hospital in Trondheim.


Tone Bull Enger et.al. Reduced Long-Term Relative Survival in Females and Younger Adults Undergoing Cardiac Surgery: A Prospective Cohort Study. PLoS One. 2016 Sep 28;11(9):e0163754.

Tone Bull Enger, physician and PhD candidate at the Department of Laboratory Medicine, Children’s and Women’s Health at NTNU.