Personalized Intervention Strategy Based on a Risk Score Generated From Subcutaneous Insertable Cardiac Monitor: Results From Phase 1 of ALLEVIATE-HF

Abstract

Background: Diagnostic variables from insertable cardiac monitors may be useful in identifying patients at increased risk of heart failure (HF) events. High-risk alerts must be coupled with interventions to improve outcomes. We aim to assess the safety of a predefined protocolized intervention pathway activated by insertable cardiac monitor high-risk alerts.

Methods and results: ALLEVIATE-HF (Algorithm Using LINQ Sensors for Evaluation and Treatment of Heart Failure) Phase 1 was a randomized interventional study enrolling patients with New York Heart Association class II/III and a recent HF event. A HF risk score based on insertable cardiac monitor diagnostics, including impedance, respiration rate, atrial fibrillation burden, heart rate during atrial fibrillation, heart rate variability, and activity duration, was calculated. A protocolized intervention pathway was activated when high-risk scores were detected that involved physician-prescribed nurse-implemented uptitration of diuretic for 4 days, unless safety rule-out conditions were met. Interventions could be repeated if high-risk scores persisted and did not require worsening symptoms. In total, 59 patients were randomized (mean age 68.2±11.8 years; 59.3% male); 67.8% with ejection fraction ≥50%. The mean follow-up was 11.8±8.1 months. Overall, 146 high-risk scores were recorded in 33 patients and 118 interventions occurred in 75 (51.4%) high-risk alerts that did not meet safety rule-out criteria. There were no serious adverse events and 13 adverse events related to interventions. In patients with symptoms at intervention initiation, symptoms resolved in 37 interventions (80%) and worsened in 8 (17%). In asymptomatic patients, symptoms developed in 3 interventions (7%).

Conclusions: A personalized medication intervention based on insertable cardiac monitor risk score can be safely instituted in patients with HF, irrespective of symptoms.

Registration: URL: https://www.clinicaltrials.gov; Unique Identifier: NCT04452149.

Keywords: heart failure; protocolized intervention pathway; remote monitoring; risk metric.

Figure 1. A basic schematic of the HF risk score‐based protocolized intervention pathway.

BP indicates blood pressure; COPD, chronic obstructive pulmonarydisease; HF, heart failure; Meds, medications; and PRN, pro re nata or as needed.

Figure 2. A diagram describing the breakdown of high‐risk score alerts, PRN interventions, and symptom resolution during the intervention period in Phase 1 of the ALLEVIATE‐HF study.

AE indicates adverse event; ALLEVIATE‐HF, Algorithm Using LINQ Sensors for Evaluation and Treatment of Heart Failure; HF, heart failure; PRN, pro re nata or as needed; Pts, patients; and SAE, serious adverse event.