For heart failure patients with obvious symptoms, surgery has long been associated with a greater risk of complications and death. But the current study offers fresh evidence that even heart failure patients without symptoms have an increased mortality risk, said senior study author Dr. Sherry Wren, vice chair of surgery at Stanford University School of Medicine and chief of general surgery at Palo Alto Veterans Health Care System.
Researchers analysed 90-day surgical mortality rates for nearly 48,000 patients with heart failure and nearly 562,000 patients without heart failure. None of them had emergency operations or heart surgery.
During the study, 2,635 people with heart failure, or 5.5 percent, died within 90 days of their operations, as did 6,881 patients without heart failure, or 1.2 percent.
Symptomatic heart failure patients were more than twice as likely to die as people without heart failure, the study found. Asymptomatic heart failure patients were still 53 percent more likely to die.
Heart failure happens when the heart muscle is too weak to pump enough blood through the body. Symptoms can include fatigue, weight gain from fluid retention, shortness of breath and coughing or wheezing.
Patients with heart failure can also develop what's known as a decreased left ventricular ejection fraction, or a reduced ability of the heart's main pumping chamber to push oxygenated blood out of the heart into the rest of the body.
In the study, even heart failure patients without symptoms and with a normal ejection fraction were still 46 percent more likely to die after surgery than people without heart failure.
The heart failure patients were more likely to be male, obese, white, and older -- 69 years old on average compared with 59 for people without heart failure. They also tended to have more complex chronic health problems than people without heart failure.
Patients with heart failure also underwent more complex operations than people without heart failure.
One limitation of the study, published in JAMA, is that long-term survival rates might be different than the 90-day results examined in the study.
Even so, the results confirm that all heart failure patients need to be cautious about approaching elective surgery and make sure they manage their disease as much as possible before their operations, said Dr. Amrut Ambardekar, a cardiology researcher at the University of Colorado Anschutz Medical Campus in Aurora, who wasn't involved in the study.