Discovery of important links between heart failure and complications during non-cardiac surgery

In the largest study of its kind in the U.S., researchers from Duke University have identified a possible "perfect storm" of factors pushing heart failure to the forefront of risks for complications after surgery in the elderly.

Adrian F. Hernandez, M.D., said that three concurrent trends in the next ten to twenty years point to a need for evaluation of outcomes after non-cardiac procedures among patients with heart failure: An elderly population increase of 50 percent, an increased number of surgical procedures in this population, and increasing prevalence of heart failure in the general population.

Dr. Hernandez and colleagues reported in the April issue of Anesthesiology that elderly patients with heart failure who undergo major surgical procedures have substantially higher risks of surgical mortality and hospital readmission than other types of patients – including those with coronary disease – admitted for the same procedure.

Heart failure is defined as a weak heart that causes patients to have shortness of breath, fatigue or problems with swelling in their legs.

Finally, until Dr. Hernandez's study, data on the effects of non-cardiac surgery on patients with heart failure has been hard to come by.

“Professional guidelines and previous studies have generally focused on patients undergoing surgery with a history of heart attacks rather than congestive heart failure,” said Dr. Hernandez. “And because of limitations in previous studies, it is difficult to fully understand the impact of heart failure in the perioperative setting.”

Past estimates put heart failure prevalence in the surgical population at between 5 to 12 percent. Dr. Hernandez's study showed an almost 20-percent prevalence of heart failure in the elderly undergoing common surgical procedures.

The study looked at 159,327 patients undergoing major non-cardiac surgery from 2000-04. Patients were then divided into three groups: those with heart failure with or without coronary artery disease (CAD); coronary artery disease only and those without either heart failure or coronary artery disease. The researchers then observed mortality rates and 30-day readmission rates of the patients.

“We observed a 63-percent greater risk of operative mortality and a 51-percent greater risk of 30-day readmission among patients with heart failure compared to patients without heart failure or CAD,” said Dr. Hernandez. “To put the risk due to heart failure in context, only emergent or urgent surgeries were more important than heart failure for predicting death. Furthermore, heart failure was the most important factor for predicting readmission. ”

As the physicians most responsible for maintaining patients' vital functions during surgery, the results of this study are especially useful to anesthesiologists.

Although professional guidelines have provided uniform, evidence-based approaches to the care of patients undergoing major non-cardiac procedures, improvements in the care of patients with heart failure in this setting are greatly needed, said Dr. Hernandez.

“Anesthesiologists and other physicians should ensure that patients with heart failure are as stable as possible with minimal symptoms and are on optimal medications before surgery,” said Dr. Hernandez. “In addition, physicians should pay close attention to patients' early postoperative care as well as establish early follow-up after discharge to identify signs or symptoms of worsening heart failure as early as possible.”