Safety Data Favor Diuretic Strategy Triggered by Cardiac Monitoring Alerts in HF

For a range of hospitalized patients at risk of worsening heart failure (HF), tying medical interventions to cardiac monitoring seemed safe thus far according to the small ALLEVIATE-HF trial.

There were no serious adverse events observed when people equipped with a subcutaneous insertable cardiac monitor (ICM) were subject to an intervention in which high-risk alerts issued by the device triggered physician-prescribed, nurse-implemented uptitration of diuretics for 4 days — unless safety rule-out conditions were met — and the intervention was repeated if high-risk scores persisted, regardless of symptoms.

There were 13 adverse events related to the intervention in 59 people, three of them related to the Reveal LINQ ICM system, and one of those being a device extrusion, according to Rami Kahwash, MD, of the Ohio State University Wexner Medical Center in Columbus, Ohio, and collaborators of phase 1 of the ALLEVIATE-HF study published in the Journal of the American Heart Association.

It also appeared that the intervention resolved symptoms in 80% of symptomatic cases and prevented HF symptoms in 93% of asymptomatic patients; only 7% of asymptomatic people at baseline eventually developed symptoms during follow-up averaging 11.8 months.

How effective the intervention really is at improving HF outcomes is currently under further assessment in the larger phase 2 of the ALLEVIATE-HF study.

“These results address an important gap in remote monitoring management of HF by establishing a connection between alerts and action. They offer an early intervention strategy that can be safely implemented before symptoms occur,” the investigators maintained.

The ultimate goal is to reduce the number of hospitalized HF patients who, after discharge, continue to experience symptoms and are readmitted.

Ting-Tse Lin, MD, PhD, and Jyh-Ming Jimmy Juang, MD, PhD, both of National Taiwan University College of Medicine and Hospital in Taipei, agreed that the ALLEVIATE approach “addresses a critical gap in current HF management: connecting remote monitoring data with actionable interventions.”

“As the field progresses, it will be essential to address the integration of these systems into existing healthcare infrastructures and ensure that they are accessible to a diverse patient population. The success of this model in phase 1 of the study sets a strong foundation for the ongoing larger, blinded, randomized phase 2 trial, which will further assess the efficacy of this intervention strategy on a broader scale,” the pair commented in an accompanying editorial.

The ALLEVIATE-HF group had opted to use ICMs in the study because these minimally invasive devices can be used in a wider pool of HF patients than cardiac implantable electronic devices and are less invasive than direct pulmonary artery hemodynamic sensors. ICMs offer continuous ECG, tissue impedance, and 3-axis accelerometry that capture impedance, respiration rate, atrial fibrillation (Afib) burden, heart rate during Afib, heart rate variability, and activity duration.

Based on these variables, 33 ICM patients had 146 high-risk scores recorded in the study, roughly half of which met safety criteria for nurses to proceed with the diuretic intervention.

Kahwash’s group stressed the safety of the study intervention when provided by properly trained HF nursing staff.

“Only [eight] interventions did not complete the 4-day diuretic intensification course due to safety concerns for symptoms commonly seen in the acute diuresis phase, such as polyuria, muscle cramps, and palpitations. Available assessment of serum electrolytes and renal function in patients whose interventions were stopped early did not show acute changes,” the authors reported.

“Most notably, there were no safety concerns when interventions were applied to patients who were asymptomatic at intervention initiation,” they added.

Phase 1 of ALLEVIATE-HF enrolled people in New York Heart Association class II/III who had had a recent HF event from 2020 to 2021. Those randomized to observation had an observation period that lasted for 7 months, after which all participants ended up in the intervention arm per protocol.

There were 59 patients randomized (mean age 68.2 years; 59.3% men). Just over two-thirds had a left ventricular ejection fraction of at least 50%.

Kahwash and colleagues acknowledged that the small sample and lack of a real control arm were important limitations of the study.