Simple breath test might diagnose heart failure
An experimental breath test, designed to quickly identify patients suffering from heart failure simply by analyzing the contents of a single exhaled breath, has demonstrated promise in early trials, a team of researchers said.
The investigators stressed that their evaluation is based on a small group of participating patients, and that more extensive research will have to be done to confirm their initial success.
But by subjecting a patient's breath to a rigorous but fast analysis of the hundreds of volatile organic compounds contained therein, the study team said it has so far been able to correctly diagnose heart failure among newly hospitalized patients with 100 percent accuracy.
“Every individual has a breath print that differentiates them from other people, depending on what's going on in their body,” explained Dr. Raed Dweik, the study lead author and a staff physician in the department of pulmonary, allergy and critical care medicine with the Respiratory Institute at Cleveland Clinic. “And that print can tell us a lot about a person, what they've been exposed to and what disease they have.
“That's what makes the new field of breath testing so promising, because it is nonintrusive, so there is no risk involved,” Dweik said. “And you can do it anywhere — in a clinic, in a hospital, anywhere.”
The findings were published March 25 in the Journal of the American College of Cardiology.
The study authors pointed out that the most common reason American patients are admitted to a hospital is when there is a suspicion of heart failure — a tough-to-treat condition in which the heart's pumping action grows gradually weaker over time.
Now a diagnosis of heart failure comes from a variety of factors, according to the U.S. National Heart, Lung, and Blood Institute. These include medical history and symptoms, and a physical exam in which a doctor will listen to a patient's heart and lung sounds as well as check ankles, feet, legs and abdomen for signs of fluid buildup. Blood tests and an electrocardiogram can help confirm that heart failure exists.
Dr. Gregg Fonarow, a professor of cardiology at the University of California at Los Angeles, said that if research were able to establish its effectiveness, a breath-driven tool for identifying heart failure would be a helpful diagnostic innovation — but more so in a doctor's office or clinic than in the hospital.
“If it is clear that it is highly reliable and specific and sensitive, then yes, it would be a welcome advance,” Fonarow said. “But I would say it would be perhaps more helpful for primary care physicians in an outpatient setting, because that is where it's most challenging to identify heart failure.
“Today a diagnosis in that environment is based on a patient's history and exam, but symptoms for heart failure can easily overlap with a lot of other diagnoses. And the blood work that would be taken in a doctor's office might not come back until the next day, delaying identification,” he noted.
“So a breath test would be most useful in that kind of challenging situation,” Fonarow added. “But in an emergency room, while there are challenges as well, bedside blood tests are much more readily drawn and quickly analyzed so you can often get the results in minutes. So there may be potentially less of a role for a breath test in that kind of setting.”