Durham, NC - Patients undergoing major noncardiac surgery have significantly increased risks of operative death or short-term readmission if their clinical picture also includes CAD or heart failure, compared with having neither condition, suggests an analysis of a huge Medicare cohort that controlled for type of surgery [1]. It also found that the associated risks were much greater for heart failure than for CAD.

The study provides a contemporary perspective on a recognized phenomenon, according to senior author Dr Adrian F Hernandez (Duke University, Durham, NC), who observed for heartwire that much of what's known about the impact of heart failure on surgical outcomes is from an era when its pharmacologic therapy was less sophisticated and less often optimal. Since then, he added, there have also been advances in anesthesia and surgical techniques.

The group's report, with lead author Bradley G Hammill (Duke University), was published online March 25, 2008 in Anesthesiology and slated for the journal's April 2008 issue. It covered Medicare records from 159 327 patients who underwent a major noncardiac surgery from 2000 to 2004, of whom about 18% and 34% had preoperative primary diagnoses of heart failure and CAD, respectively, with the remainder having neither condition.

The most common surgeries were hip and knee replacement, observe Hammill et al; others included carotid endarterectomy, lower-extremity bypass, open repair of abdominal aortic aneurysm, other open and laparoscopic abdominal procedures, and cancer resections.

The list includes surgeries that are common in the elderly and considered high risk, but "there were, surprisingly, also surgeries that are normally considered low risk, such as laparoscopic cholecystectomy," Hernandez said. "But we see the same [risk] relationships regardless of the procedure."

The risk of both end points was significantly increased in patients with heart failure regardless of whether they also had CAD, according to Hernandez, "so it's really the heart failure driving the risk, as opposed to coronary disease on top of heart failure." Both risks were significantly elevated, as well, in the subgroup of 93 689 patients who did not have diabetes, a history of stroke, or kidney disease.

The group didn't collect data on causes of death or rehospitalization, so they couldn't pin down specific factors responsible for the increased risks, Hernandez said. "This is a kind of 40 000-foot view." Among the next steps, he added, might be to explore possible ways to risk-stratify heart-failure patients undergoing noncardiac surgery for perioperative mortality, such as, for example, with natriuretic peptide testing.