The incidence of heart failure (HF) continues to increase rapidly—exceeding six million patients in the U.S., according to the CDC—but new clinical developments may trigger a much more significant hike in HF within the next decade.

The lingering effects of long-COVID and long-term consequences of nonalcoholic fatty liver disease (NAFLD) are the primary drivers, says Marat Fudim, MD, MHS, a Duke advanced heart failure specialist and director of remote cardiac monitoring.

While the two HF subtypes are estimated to be equal in prevalence, Fudim says, the diagnosis of HF with preserved ejection fraction (HFpEF) is more challenging than HF with reduced ejection fraction (HFrEF).

The major challenge in diagnosing HFpEF is the constellation of diverse symptoms that may be present among patients. Shortness of breath is a common reason patients seek care, but it is often associated with comorbidities.

“Because of our aging population and obesity crisis, we see an enormous heart failure wave forming and it’s rolling our way,” Fudim says. “This will present significant risk to our health care systems because of the thousands of hospitalizations these patients will require.”

Fudim estimates that HF incidence within the U.S. may be higher than the CDC projects because a large portion of patients with HFpEF are either undiagnosed or misdiagnosed with other conditions. “The combination of these factors will force a paradigm shift in our approach to and management of the HF in the future,” he says.

Analyzing national COVID hospitalization rates, Fudim and colleagues estimate that 46% of patients hospitalized with long COVID developed HF symptoms within 12 months. The CDC reports that approximately 7.5%  of the US population has long COVID symptoms, defined as lasting three or more months since first contracting the virus. Even if patients with COVID are not hospitalized, they continue to be at risk of developing long COVID, which mimics HF symptoms.

A similar trend is evident among patients with NAFLD, Fudim says. Between 20 and 60% of patients diagnosed with NAFLD developed HF in subsequent years, according to the disease registry. Among that group of patients, 25% are at risk of developing HF within five years—a much faster rate than normal HF progression.

The most common liver disease, NALFD affects 30% of the US, recent studies show. Nonalcoholic steatohepatitis (NASH), a NALFD subtype, affects 5% of the US population.

HFpEF is a challenging condition to diagnose correctly, Fudim says, because patients usually present with relatively common symptoms--shortness of breath, fatigue, or fluid-retention. Their ejection fraction is usually normal.

“In my practice, every 4^th or 5^th person coming in for assessment lacks a diagnosis that explains their symptoms,” Fudim says. “We see a lot undiagnosed HFpEF and a great deal of mislabeling of HF.

“An accurate diagnosis is more important than ever because we finally have treatment options,” Fudim says. “These include pharmacological agents, but also several device-based technologies are under investigation that offer promise to the HFpEF field.”

Early, accurate diagnosis is critical to successful management of HF, Duke specialists say, and is particularly important for patients who are candidates for HFpEF. Duke cardiologists offer several tools for patients who are referred for assessment.

Physical exams, echocardiograms, and biomarker testing are common diagnostic tools. Fudim considers invasive hemodynamic testing the “gold standard.” Although not yet in widespread use, Duke HF specialists who treat patients with HFpEF perform invasive cardiopulmonary exercise testing. Accurate results depend on measurements in both supine and upright positions, Fudim says.

“It’s important to recognize that making a HF diagnosis remains complex because the condition is often the result of multiple comorbid conditions, and the cardiovascular impairment is not apparent in many cases unless proper testing is deployed.

“As a result, we have many people diagnosed with lung disease or with obesity or age-related conditions,” Fudim says. “If you don’t test, you don’t know.”