Postop AF Portends Higher Risk of HF Hospitalization in the Next Few Years

Patients who develop postoperative atrial fibrillation (POAF) are at increased risk of being hospitalized for heart failure (HF) within a few years, a retrospective cohort study of 3 million people shows. The association, though stronger for patients undergoing noncardiac surgery, is also seen after cardiac surgery.

Prior studies have drawn a link between POAF and higher risk of mortality and stroke. The investigators say that their findings, published in the European Heart Journal, provide further argument that it’s worth taking heed of POAF.

Hooman Kamel, MD (Weill Cornell Medicine, New York, NY), the study’s senior author, said that the overlap between “atrial fibrillation and heart failure has been well appreciated for a long time.” Yet when the arrhythmia occurs in the context of surgery, there has been the sense that it’s a “distinct and maybe less-serious condition than A-fib that happens spontaneously,” with few data in the literature about how the complication relates to HF, he told TCTMD.

Given what’s known about the “pathophysiological links” between heart failure and atrial fibrillation more generally, the results specific to POAF don’t come as a complete surprise, said Kamel. “But at the same time, because it has such clinical implications for patients, it was important to demonstrate that there is this link.”

Healthcare professionals may be reluctant to see a short-term condition that resolves as something that requires long-term monitoring, he acknowledged. However, “more and more, the data are making it clear that, unfortunately, that is the case,” Kamel noted. “This is not just a transient event. It’s a marker of underlying derangements that can put the patient at risk for future events.”

Maya Guglin, MD, PhD (Indiana University School of Medicine, Indianapolis), chair of the American College of Cardiology’s Heart Failure and Transplant Council, similarly said that the study results are “certainly interesting” but “not unexpected.”

“I think these findings are very intuitive. But having said that, nothing like this has been studied in so much detail and so systematically before, so it clearly adds to the knowledge base” on a clinically relevant topic, Guglin commented to TCTMD.

Links for Both Cardiac, Noncardiac Surgery

Led by Parag Goyal, MD (Weill Cornell Medicine), the researchers analyzed administrative claims data for emergency department visits and acute care hospitalizations at nonfederal facilities in 11 states: Arkansas, Florida, Georgia, Iowa, Maryland, Massachusetts, Nebraska, New York, Utah, Vermont, and Wisconsin, which have a combined population of around 80 million people and represent 25% of the total US population.

Altogether, data were available for 3,006,390 patients, treated between 2016 and 2018, without preexisting HF who survived undergoing surgery. Their mean age was 57 years, and 60% were women. Median follow-up duration was 1.7 years.

Within that group, 76,536 patients had undergone cardiac surgery, of whom 18.8% developed POAF and 16.3% had previously been diagnosed with AF. The rate of HF hospitalization per 1,000 person-years was 66 for patients with POAF, 98 for those with AF, and 44 for those with neither.

The remaining roughly 2.9 million patients underwent noncardiac surgery, of whom 0.8% had incident POAF and 6.4% had preexisting AF. For them, the rate of HF hospitalization per 1,000 person-years was 66 with POAF, 85 with AF, and 17 for those with neither.

In an adjusted Cox model that took into account sociodemographic factors and comorbidities, POAF and preexisting AF both were linked to incident HF hospitalization.

Risk of Incident HF Hospitalization

Even when excluding HF that occurred within 1 year of surgery, the link between POAF and HF remained, albeit attenuated.

For Kamel, it seems there’s a “bidirectional link” between AF and HF. “We think that they’re each driving the other,” he explained.

He cautioned that their study is one of the first to show the association and there’s much yet to learn about mechanism. RCTs must also test different treatment strategies. Before there are specific recommendations, though, one given is the need to thoroughly evaluate patients who have POAF, Kamel said. “Just paying attention to: does this patient already have symptoms and signs of heart failure, and it just hasn’t been diagnosed?” It’s also important to watch for recurrence of AF, he added.

When we face [POAF], we have to recognize it needs to be taken seriously and treated. Maya Guglin

Guglin noted that there are no known ways to prevent POAF. This makes it all the more crucial, then, that “when we face it, we have to recognize it needs to be taken seriously and treated,” she urged, adding, “Manage it aggressively, trying to restore sinus rhythm, whether you use amiodarone, other medications, or cardioversion, because this is the most reliable way to prevent further complications like an increased number of heart failure hospitalizations.”

Today, “postoperative atrial fibrillation is seen by many as [more of a] nuisance. Everybody knows it happens,” said Guglin. “Everybody knows it is easy to control and most of the time it is self-limited. People don’t pay too much attention to it,” much less monitor patients thereafter.

Melissa E. Middeldorp, MD (Cedars-Sinai Smidt Heart Institute, Los Angeles, CA, and University of Adelaide, Australia), and Christine M. Albert, MD (Cedars-Sinai Smidt Heart Institute), in an editorial, agree that POAF appears to be “not just a transient response to surgery but may be reflective of underlying atrial and myocardial structural changes” that can lead to both the arrhythmia and heart failure.

But “often it can be difficult to tease apart which came first,” Middeldorp and Albert note. “Given the number of shared risk factors between the two conditions, such as hypertension, diabetes, ischemic heart disease, and valvular heart disease, there is likely significant overlap in the development of the predisposing substrate in both the atria and the ventricle. Thus, POAF may be a marker of both developing disease processes.”

What’s needed now, they say, is better understanding of who’s at highest risk of HF among the broad population of patients who develop POAF, opening the door to early aggressive intervention.