Traditional cardiovascular revascularization trials have long been designed by clinicians to examine outcomes that are predominantly of interest to clinicians. These trials are sometimes referred to as “tombstone trials” within the medical community for their tendency to focus on death or other adverse cardiac events after heart surgery or other therapies.
While so-called tombstone trials are extremely important for informing physicians about a patient’s likelihood of surviving an operation, they do very little to help patients gauge and understand how their lives will be impacted afterward.
Dr. Louise Sun, a cardiac anesthesiologist at the University of Ottawa Heart Institute, and an adjunct scientist with the Institute for Clinical Evaluative Sciences (ICES), is the principal investigator of a new study which examines outcomes defined by patients as being desirable following coronary artery bypass grafting (CABG) surgery.
“When it comes to cardiovascular medicine, all existing trials to date have been clinician-centered, meaning they are designed to look at death and major adverse cardiac events,” said Dr. Sun. “Our study is the first in the field to ask patients to define ‘disability’ as something that is truly relevant to them, and to understand how big of a problem ‘disability’ is in men and women following cardiac surgery.” Dr. Sun’s study, titled “Disability-Free Survival after Coronary Artery Bypass Grafting in Women and Men with Heart Failure,” is published in Open Heart.
Dr. Sun et al, in collaboration with the Patient Alumni Association of the University of Ottawa Heart Institute, surveyed more than 3,000 patient alumni living with heart disease to determine a patient-centered disability outcome.
“Our survey helped to establish what patients believe to be important aspects of disability after surgery,” said Sun. “We were trying to get a better sense, for example, of whether patients were willing to sacrifice longevity for better quality of life.”
The outcome, as defined by the UOHI’s patient alumni, was a composite of stroke, nursing home admission and more than 3 non-elective hospitalizations per year.
“What our research tells us is patients care more about whether or not they can expect to return to their normal level of function post-op, or whether they can dodge going to a long-term care facility, more-so than whether or not they will just survive the operation,” concludes Sun and her team.
The team evaluated the burden of postoperative disability in all patients who had CABG surgery in Ontario between 2008 and 2015. Over 40,000 patients were studied. As Dr. Sun explains, “with the help of ICES administrative data, we have the ability of knowing if patients were admitted to a hospital multiple times in the year following their procedure, or if they ended up in a nursing home, or if they meet any of the other patient-defined criteria for disability.”
Interestingly, only 20.6% of all patients who had CABG surgery were women. The team found that disability happened more commonly than death in the year after CABG (5.4% of patients developed a new disability while 3.7% died). Overall, women had a 25% higher risk of becoming disabled after CABG than men, and women with heart failure were particularly prone to developing this complication.
“Older women (over 75 years), and women with heart failure, prior stroke, and kidney disease, are particularly susceptible,” says Dr. Sun.
Dr. Sun said efforts should be dedicated to making mathematical models to predict one’s risk of disability, as this will enable patient-centered decision-making of whether surgery is something they would want. The team is also hoping to engage in the development of sex-specific medical and surgical strategies to improve outcomes in the future.
“The next steps would be to determine whether we can build mathematical formulas to predict the risk of disability,” she said. “This will enable us to develop a decision aid that will bring patients, family members and physicians together to make more informed treatment decisions as a team.”
“The ultimate goal of our research is to bring patients back to the centre of the care they receive.”
The researchers would like to thank Mr. Jean Bilodeau, President of the UOHI Patient Alumni Association, and its alumni members for their support in getting this study off the ground.
Dr. Sun would like to acknowledge the contribution of her friend and mentor, Dr. Jack Tu, who passed away during the initial revisions of this manuscript.