Reductions in hospitalizations and deaths likely result from earlier intervention and more frequent treatment adjustments

NEW ORLEANS (March 29, 2026) — Treatment management guided by the use of a noninvasive device to monitor fluid accumulation in the lungs substantially reduced hospitalizations and deaths among patients with heart failure with preserved ejection fraction (HFpEF), according to research presented at the American College of Cardiology’s Annual Scientific Session (ACC.26).

Patients whose treatment management involved the use of the device were 74% less likely to be hospitalized for heart failure and 74% less likely to die from heart failure during a follow-up of more than three years. Researchers attribute the benefits to an enhanced ability to detect fluid buildup early and fine-tune medications in response to the level of lung congestion. Clinicians adjusted medications more than twice as frequently, and adjustments were made significantly earlier in the development of lung congestion when using the CardioSet Edema Guard Monitor to guide treatment, researchers said.

“This device offers a way to change the treatment of patients with heart failure in order to start treatment early—before the patient starts to experience symptoms,” said Michael Kleiner-Shochat, MD, professor and head of the heart failure clinic at Hillel Yaffe Institute of Cardiology in Hadera, Israel, and the study’s first author. “The secret of success is to enable us to intervene at the preclinical stage when the reaction to treatment is more powerful.”

Heart failure is when the heart muscle becomes too weak to squeeze as effectively as it should or too stiff to relax and fill properly with blood, reducing the ability to pump blood throughout the body and causing the gradual accumulation of fluid in the lungs (congestion). Progression, or worsening, of lung congestion is the most common cause of heart failure hospitalizations and is managed primarily with diuretics to remove excess fluid from circulation.

CardioSet is one of several devices designed to monitor lung congestion. It was previously shown to improve outcomes among patients with heart failure with reduced ejection fraction (HFrEF), the type of heart failure caused by weakened heart muscle. The new study results suggest its benefits are even more pronounced in patients with HFpEF, the type in which the heart muscle does not relax enough to fully fill with blood.

The device works by measuring resistance to electrical current, or impedance. Lungs become less resistant to electrical current as fluid accumulates, causing impedance to go down. When lung impedance is measured with noninvasive devices, measurements include lung impedance data as well as a much larger noise signal that comes from the surrounding chest wall, which has limited the accuracy of previous noninvasive techniques, according to Kleiner-Shochat. The CardioSet device overcomes this limitation by using a configuration of more electrodes, which enables the larger noise signal from the chest wall to be calculated and eliminated, providing an accurate assessment of lung impedance even when the change in fluid accumulation is small, he said.

“It’s a simple, scalable device that could be used at each point of care—in clinics and, in the future, in the patient’s home—and you can get indications about the patient’s lung fluid status very quickly,” said Kleiner-Shochat, who is also the founder of CardioSet Medical, maker of the CardioSet device, and a member of its Board of Directors.

Researchers enrolled 150 patients with HFpEF; half were randomized to receive lung-impedance guided care at each monthly outpatient clinical visit and half received standard care. Baseline characteristics were similar between groups, and the number of outpatient clinic visits was equal. CardioSet was used to measure pulmonary congestion during each outpatient visit for all patients, but treating physicians were aware of the results of lung impedance measurements only in the lung-impedance guided group. Physicians made treatment adjustments according to study protocols. Patients were followed for a median of 38.4 months.

The study’s primary endpoint was recurrent heart failure hospitalization. Researchers tracked 19 events in the lung-impedance guided group and 93 events in those receiving standard care, a 74% reduction in favor of the lung-impedance guided arm. The time to first heart failure hospitalization was also significantly longer in this group at 602 days on average versus 83 days among those receiving standard care.

Mortality outcomes were also significantly improved among patients receiving lung-impedance guided care. Compared with standard care, these patients showed a 60% lower rate of all-cause death and a 74% lower rate of death from heart failure during the three-year follow-up. There were no device-related adverse events.

Researchers said the benefits shown in the trial exceed the benefits reported in a previous trial involving patients with HFrEF. They said that lessons learned from the previous trial may have helped participating clinicians feel comfortable using diuretics more aggressively in response to signals from lung impedance monitoring. In addition, the same dose of diuretics may have a stronger effect in patients with HFpEF than those with HFrEF due to physiological differences between the two types of heart failure.

The trial was limited to a single center. Kleiner-Shochat said that a study conducted at multiple sites across different countries could help to confirm the feasibility and effectiveness of lung-impedance guided heart failure treatment in a broader range of settings.

The study was conducted at the Hillel Yaffe Medical Center without external funding.

Kleiner-Shochat will present the study, “Lung Impedance-guided Therapy in Heart Failure with Preserved Ejection Fraction: Results of a Randomized Clinical Trial,” on Sunday, March 29, at 10:45 a.m. CT / 15:45 UTC in the Main Tent, Great Hall.

ACC.26 will take place March 28-30, 2026, in New Orleans, bringing together cardiologists and cardiovascular specialists from around the world to share the newest discoveries in treatment and prevention. Follow @ACCinTouch, @ACCMediaCenter and #ACC26 for the latest news from the meeting.

The American College of Cardiology (ACC) is the global leader in transforming cardiovascular care and improving heart health for all. As the preeminent source of professional medical education for the entire cardiovascular care team since 1949, ACC credentials cardiovascular professionals in over 140 countries who meet stringent qualifications and leads in the formation of health policy, standards and guidelines. Through its world-renowned family of JACC Journals, NCDR registries, ACC Accreditation Services, global network of Member Sections, CardioSmart patient resources and more, the College is committed to ensuring a world where science, knowledge and innovation optimize patient care and outcomes. Learn more at ACC.org.

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