Closer HF Assessment Fine-Tunes Surgical Risk Evaluation

Heart failure patients didn’t have to have clinical symptoms or a reduced ejection fraction to have a raised mortality risk after elective non-cardiac surgery, researchers said.

Whereas heart failure status alone was associated with more postoperative deaths at 90 days (5.49% vs 1.22% for patients without heart failure, adjusted OR 1.67, 95% CI 1.57-1.76), varying degrees of ventricular dysfunction and symptoms appeared to make their own contributions to mortality risk:

• Symptomatic heart failure: 10.11% vs 1.22% (adjusted OR 2.37, 95% CI 2.14-2.63)
• Asymptomatic heart failure: 4.84% vs 1.22% (adjusted OR 1.53, 95% CI 1.44-1.63)
• Heart failure with preserved ejection fraction: 4.42% vs 1.22% (adjusted OR 1.46, 95% CI 1.35-1.57)

Symptomatic patients tended to have a higher risk than did asymptomatic patients, as did those with lower ejection fraction, reported Sherry Wren, MD, of Stanford University in Palo Alto, California, and colleagues in JAMA.

They concluded that heart failure is a “marker for a constellation of comorbidities that patients with heart failure tend to have, all of which contribute to the elevated risk. Heart failure itself has a relatively small effect as an independent risk factor of postoperative mortality.”

Poor left ventricular function has long been known to be a predictor of adverse outcome in non-cardiac surgery.

Now the analysis by Wren’s group “provides a more detailed description of the associations of increasing levels of systolic dysfunction and the presence or absence of heart failure symptoms with surgical outcomes than previously documented,” according to an editorial in JAMA Surgery by John Ikonomidis, MD, PhD, of University of North Carolina at Chapel Hill.

He pointed out that procedural complexity also matters in non-cardiac surgery, citing the increase in 90-day postoperative mortality rates from 4.6% for standard complexity operations to 10.3% for complex procedures among patients with heart failure (or from 0.7% to 6.2% in those without heart failure) observed in the study.

“Overall, the data reported here is highly valuable and comprehensive information that practitioners can use for preoperative planning and also in discussions with patients,” Ikonomidis wrote.

The study was based on the Veterans Affairs Surgical Quality Improvement Project database listing more than 600,000 patients as having gotten surgery from 2009 to 2016. Of those, 7.9% had heart failure going into the operating room (mean age 68.6; 2.9% women).

Heart failure patients got more complex procedures than the others. At the same time, they comprised an older group with fewer women as well as higher rates of obesity and comorbidities.

“Although optimizing their cardiac function should be pursued, all other associated modifiable risk factors that might contribute to postoperative mortality should also be optimized since heart failure by itself has a relatively small association with mortality,” Wren and colleagues suggested.

Their nonrandomized data left room for possible unmeasured confounding, however, and the nature of the dataset also meant that they were limited to patients deemed “fit for surgery,” the authors acknowledged.