BACKGROUND:Arrhythmia burden in ambulatory patients with symptomatic heart failure (HF) without cardiac implantable electronic devices (CIEDs) is not well defined, and it remains uncertain whether device-guided remote congestion management modifies arrhythmia occurrence. OBJECTIVES:The goal was to assess whether arrhythmia burden differed between randomized congestion-management strategies and characterize the occurrences and associations of insertable cardiac monitor (ICM)-detected arrhythmias with therapeutic actions and clinical events. METHODS:In ALLEVIATE-HF, patients with NYHA functional class II-III HF with any ejection fraction (EF) and a recent HF event, without prior CIEDs, underwent ICM implantation and were randomized to ICM-guided, physician-directed, nurse-facilitated congestion management or usual care. In both arms, arrhythmia data were accessible to investigators, and arrhythmia-related management was clinician directed. Arrythmia occurrence was estimated using Kaplan-Meier methods. Associations with therapeutic interventions and clinical events were evaluated using time-varying Cox models. RESULTS:The analysis included 711 patients (mean age 70.5 ± 10.4 years; 45.7% women; mean follow-up 17.3 ± 8.9 months); 67.9% had HF with preserved EF, and 60.2% were NYHA functional class II at baseline. During the 13-month randomized phase, arrhythmia occurrence rate did not differ between the study arms. The 3-year overall occurrence of atrial fibrillation (AF) was 66.6%, with an incidence of new-onset AF of 25.4%. Bradyarrhythmia occurred in 47.1% of patients, and ventricular tachycardia or fibrillation (VT/VF) in 20.1%. ICM-recorded arrhythmia was associated with subsequent increase in arrhythmia-related interventions (HR: 3.81; VT/VF and VT/VF-related interventions, HR: 7.04; AF and AF-related interventions, HR: 3.28; bradyarrhythmia and bradyarrhythmia-related interventions, HR: 7.22; all P < 0.001). ICM-recorded arrhythmia was associated with increased risk of all-cause hospitalization (HR: 1.79; P < 0.001) and HF events (HR: 1.69; P = 0.003). Therapeutic CIED implantation and ablation occurred in 22.7% and 26.1%, respectively. Bradyarrhythmias were more common in patients with EF ≥50%, whereas VT/VF occurred more frequently in EF <50%; AF occurrence was similar between EF groups. CONCLUSIONS:In ambulatory patients with recent symptomatic HF events, arrhythmia burden was not modified by the study protocol-directed, congestion-management strategy. Continuous ICM monitoring revealed a high burden of clinically meaningful arrhythmias that were associated with clinical events and therapeutic interventions. (Algorithm Using LINQ Sensors for Evaluation And Treatment of Heart Failure [ALLEVIATE-HF]; NCT04452149).

BACKGROUND:Early identification of worsening heart failure (HF) may improve outcomes. OBJECTIVES:This study aims to assess if insertable cardiac monitor (ICM)-based high-risk detection combined with centrally managed, nurse-facilitated, individually protocolized diuretic interventions is safe and improves HF outcomes. METHODS:A Reveal LINQ (Medtronic) ICM with an investigational HF risk-status software was implanted in participants with HF who were randomized 1:1 to an intervention arm (high-risk HF alert triggering protocolized diuretic regimen) or an observation arm (standard care). The primary safety endpoint was intervention-related serious adverse events and the primary efficacy endpoint was a 5-component hierarchical composite including cardiovascular death or HF hospitalization or outpatient HF event within 60 days of high-risk onset, Kansas City Cardiomyopathy Questionnaire Clinical Summary Score, and 6-minute walk distance, analyzed using win ratio. RESULTS:A total of 711 participants were randomized (357 intervention, 354 observation). The primary composite endpoint did not significantly differ between groups (win ratio: 0.79; 95% CI: 0.62-1.01; P = 0.06). Over a mean follow-up of 17.3 ± 8.9 months, the serious adverse events rate was 0.32% (95% CI: 0.10%-0.99%; prespecified safety threshold ≤5%). The cumulative cardiovascular death and HF events were numerically higher in the intervention group (HR: 1.43; 95% CI: 0.95-2.15; P = 0.091). In an exploratory sensitivity analysis adjusting for a baseline Kansas City Cardiomyopathy Questionnaire imbalance, the win ratio was 1.02 (95% CI: 0.80-1.31; P = 0.85). CONCLUSIONS:ICM-based risk status detection with centrally coordinated diuretic intervention was safe and yielded a neutral result for the primary composite outcome under the tested implementation strategy (ALLEVIATE-HF [Algorithm Using LINQ Sensors for Evaluation and Treatment of Heart Failure]; NCT04452149).

This study demonstrates that, even after controlling several physiological variables, electromyography (EMG) of the respiratory muscles is significantly associated with dyspnea, as assessed by the Borg scale in patients with chronic obstructive pulmonary disease (COPD) during daily activities. This finding suggests that respiratory EMG may serve as a physiological biomarker for dyspnea. Surface EMG measured on the chest offers valuable insights for assessing dyspnea, providing an additional, objective tool to capture the intensity of dyspnea during daily living.

BACKGROUND The novel win ratio statistic has emerged as a promising alternative end point for the comparison of 2 treatment groups on multiple end points simultaneously, but it has not been used for cardiac resynchronization therapy (CRT) trials. RE-synchronization reVErses Remodeling in Systolic left vEntricular dysfunction (REVERSE; ClinicalTrials.gov identifier: NCT00271154) was the first multicenter, randomized CRT trial in mild heart failure (HF). The primary result was a nonsignificant reduction in the proportion of CRT patients with worsened clinical composite score compared with control. However, CRT did improve reverse remodeling measures and delayed time to first HF hospitalizations. OBJECTIVE To demonstrate the value of the win ratio for the evaluation of CRT using data from REVERSE. METHODS Individual patient data were analyzed using the win ratio on a hierarchical end point at 12 months that included the following clinical composite score components: all-cause death, HF hospitalization, crossover or exit because of HF, change in New York Heart Association class from baseline, and the Patient Global Assessment. All pairs of a CRT and a control patient were compared. The win ratio is the number of CRT wins divided by the number of losses. Reverse remodeling and quality of life were assessed as alternative end points. RESULTS REVERSE included 610 patients randomized between treatment (CRT-ON, n = 419) and control (CRT-OFF, n = 191). Comparison of all 80,029 treatment/control pairs resulted in 53.5% wins, 36.9% losses, and 9.5% ties. The win ratio was 1.45 (95% confidence interval, 1.17-1.80), showing CRT superiority (P = .0009). CONCLUSION Win ratio analysis confirms the benefits of CRT beyond a single primary end point and holds promise for analysis of combined end points in CRT and other arrhythmia studies.

Background Cardiac bradyarrhythmias and tachyarrhythmias in chronic heart failure (CHF) patients are associated with increased morbidity and mortality. Insertable cardiac monitors provide a continuous, ambulatory, accurate monitoring strategy for patients with CHF who are not candidates for cardiac implantable electronic devices. Objectives This study aims to assess the occurrence of cardiac arrhythmias (CAs) in patients with CHF across the ejection fraction (EF) spectrum and not indicated for cardiac implantable electronic devices. Methods Patients with recent heart failure events enrolled in LINQ-HF (Reveal LINQ Heart Failure) and Phase 1 ALLEVIATE-HF (Algorithm Using LINQ Sensors for Evaluation and Treatment of Heart Failure) studies were implanted with an insertable cardiac monitor. All CAs were adjudicated first using an artificial intelligence model, then manually verified, and grouped into 3 categories: atrial fibrillation (AF), ventricular tachycardia (VT) or fibrillation (VF), and bradycardia/pauses. Results In total, 163 patients (mean age 67.2 ± 11.2 years, 62.6% male, 49.1% EF ≥50%, 83.4% Class III, 55.2% history of AF) were followed for 17.2 ± 9.8 months. Occurrence of AF was 59.7% at 2 years, 53.1% in heart failure with reduced ejection fraction (HFrEF) <50%, and 64.6% in heart failure with preserved ejection fraction (HFpEF) ≥50%. Incidence of AF in patients without prior AF was 23.8%, 23.9% in HFrEF, and 27.6% in HFpEF. Incidence of bradycardia or pause was 37.2% overall, (37.5% in HFrEF and 39.8% in HFpEF; 30.3% during daytime vs 19.4% during nighttime). Incidence of VT/VF was 14.3% overall, 19.8% in HFrEF, and 10.4%, in HFpEF. Conclusions In CHF patients undergoing ambulatory, continuous, accurate arrhythmia monitoring, the incidence of AF and bradycardia/pause events was high and similar in HFpEF vs HFrEF patients. VT/VF was lower in HFpEF than HFrEF, but clinically important.

AIMS:Early identification and management of worsening heart failure (HF) is necessary to prevent disease progression and hospitalizations. The ALLEVIATE-HF (Algorithm Using LINQ Sensors for Evaluation and Treatment of Heart Failure) trial is a prospective, randomized, controlled, double-blind, multicentre trial that aims to assess the safety and efficacy of using the Reveal LINQ™ insertable cardiac monitor (ICM) in patients with HF to continuously monitor and evaluate HF risk status and guide timely interventions. METHODS:The ICM algorithm uses parameters derived from electrocardiogram (atrial fibrillation [AF], ventricular rate during AF, heart rate variability, and night heart rate), three-axis accelerometer (patient activity duration), and subcutaneous bioimpedance (fluid volume, respiration rate). The trial will enroll ~760 patients with New York Heart Association class II or III HF with recent hospitalization for HF or needing intravenous diuretics in the outpatient setting or elevated natriuretic peptide levels, who do not have an implanted cardiac implantable electronic device or haemodynamic monitor. Patients are randomized to an observation or an intervention arm, where the latter will receive an intervention pathway with remote nurses implementing individualized pro re nata (PRN or 'as needed') 4-day medication interventions for acute volume management upon high risk. After 13 months of randomized follow-up, all patients enter an unblinded prolonged follow-up phase with PRN interventions upon high risk. The primary hierarchical composite endpoint for the study includes cardiovascular death, HF events, Kansas City Cardiomyopathy Questionnaire score, and 6-min walk test distance. CONCLUSION:ALLEVIATE-HF will evaluate how ICM-based HF management can impact the outcomes of patients with HF regardless of ejection fraction.

Heart failure (HF) patients with reduced ejection fraction (HFrEF), normal atrioventricular (AV) conduction and left bundle branch block (LBBB) respond well to cardiac resynchronization therapy (CRT). While guidelines give the strongest recommendation for patients with a QRS≥150 ms, evidence suggests that those with moderately wide QRS (120-149 ms) may also benefit from CRT. In select patients, including those with moderately wide QRS, adaptive CRT might offer better outcomes than conventional biventricular CRT. Asian HF patients often have moderately wide QRS, but the clinical benefit of adaptive versus conventional CRT in this population is not well-established. To test the hypothesis that adaptive CRT would increase the proportion of patients with an improved Clinical Composite Score (CCS) at 6 months compared to conventional CRT in Asian HFrEF patients with normal AV conduction, LBBB and moderately wide QRS. This randomized, multi-center, single-blinded trial enrolled Asian HF patients (between January 2020 and March 2023) receiving optimal medical therapy that had NYHA class II-IV HF symptoms, left ventricular EF ≤35%, PR interval ≤200ms, LBBB, and QRS 120-149 ms. Patients were implanted with a CRT device and 1:1 randomized to receive adaptive CRT or conventional CRT and followed for 12 months. The primary outcome was the proportion of patients with an improved CCS at 6-months. Secondary outcomes were change in NYHA class, hospitalization for worsening HF, and all-cause and cardiovascular (CV) mortality. A total of 171 Asian HFrEF patients from 8 countries were randomized to adaptive CRT (n=86) or conventional CRT (n=85). Baseline characteristics and medications were similar across therapy arms (Table 1). Mean follow-up was 11.8 and 12.1 months in the adaptive CRT and conventional CRT arms, respectively. The proportion of patients with an improved CCS at 6 months was 77% in the adaptive CRT arm and 80% in the conventional CRT arm (Figure 1; p=0.61). With both CRT therapy arms combined, the CCS at 6 months improved in 78.4% and was unchanged in 12.3%. At 6 months, 67.9% of adaptive CRT and 72.0% of conventional CRT patients had an improved NYHA class relative to baseline (p=0.47), while at 12 months, 79.8% of adaptive CRT and 72.3% of conventional CRT patients had improved (p=0.30). Compared to the conventional CRT arm, at 12 months the adaptive CRT arm had similar rates of HF hospitalization (9.4% v. 11.8%; p=0.64), all-cause mortality (7.1% vs. 5.9%; p=0.78) and CV mortality (3.5% vs. 2.3%; p=0.98). While adaptive CRT was not superior to conventional CRT, 90.6% of patients across both therapy arms benefited from CRT based on the CCS at 6 months. These findings indicate benefit of CRT in Asian HFrEF patients with normal AV conduction, LBBB, and QRS 120-149ms. A stronger level of recommendation for CRT may be warranted in this patient population.

AbstractAimsClinical pathways have been shown to improve outcomes in patients with heart failure (HF). Although patients with HF often have a cardiac implantable electronic device, few studies have reported the utility of device‐derived risk scores to augment and organize care. TriageHF Plus is a device‐based HF clinical pathway (DHFP) that uses remote monitoring alerts to trigger structured telephone assessment for HF stability and optimization. We aimed to evaluate the impact of TriageHF Plus on hospitalizations and describe the associated workforce burden.Methods and resultsTriageHF Plus was a multi‐site, prospective study that compared outcomes for patients recruited between April 2019 and February 2021. All alert‐triggered assessments were analysed to determine the appropriateness of the alert and the workload burden. A negative‐binomial regression with inverse probability treatment weighting using a time‐matched usual care cohort was applied to estimate the effect of TriageHF Plus on non‐elective hospitalizations. A post hoc pre‐COVID‐19 sensitivity analysis was also performed. The TriageHF Plus cohort (n = 443) had a mean age of 68.8 ± 11.2 years, 77% male (usual care cohort: n = 315, mean age of 66.2 ± 14.5 years, 65% male). In the TriageHF Plus cohort, an acute medical issue was identified following an alert in 79/182 (43%) cases. Fifty assessments indicated acute HF, requiring clinical action in 44 cases. At 30 day follow‐up, 39/66 (59%) of initially symptomatic patients reported improvement, and 20 (19%) initially asymptomatic patients had developed new symptoms. On average, each assessment took 10 min. The TriageHF Plus group had a 58% lower rate of hospitalizations across full follow‐up [incidence relative ratio: 0.42, 95% confidence interval (CI): 0.23–0.76, P = 0.004]. Across the pre‐COVID‐19 window, hospitalizations were 31% lower (0.69, 95% CI: 0.46–1.04, P = 0.077).ConclusionsThese data represent the largest real‐world evaluation of a DHFP based on multi‐parametric risk stratification. The TriageHF Plus clinical pathway was associated with an improvement in HF symptoms and reduced all‐cause hospitalizations.

Abstract Aims We aim to evaluate the incidence of atrial fibrillation (AF) in a large real‐world cohort of patients implanted with an insertable cardiac monitor (ICM) who had a clinical history of symptomatic heart failure (HF) with reduced or preserved left ventricular ejection fraction (LVEF). Methods Patients with an ICM and a history of HF events were identified from the Optum® de‐identified Electronic Health Record dataset merged with an ICM device dataset collected during 2007–2021. All ICM‐detected AF episodes that were available with ≥30‐s of ECG at onset were adjudicated using artificial intelligence (AI model). Episodes with AI model probability of AF ≥ 0.9 were analysed. The Kaplan–Meier incidence of AF as a function of episode duration, history of AF, and LVEF were assessed. Results A total of 1020 patients with ICM were identified of whom 911 had ≥180 days of follow‐up and were included. According to the AI model, 358 patients had 8407 episodes of true AF. Incidence of AF at 42 months was 45.6% (44.1% vs. 46.8% in reduced vs. preserved LVEF). Incidence of new‐onset AF was 23.2% (23.3% vs. 22.2% in reduced vs. preserved LVEF) in patients with no clinical history of AF. Patients with new‐onset AF had a higher HF event rate compared with patients who had no clinical history of AF and did not develop AF during follow‐up [OR = 2.73 (1.47–5.09); P = 0.002]. Patients with preserved LVEF had more longer duration paroxysmal AF compared with those with reduced LVEF (44.5% vs. 33.9%, P = 0.02). Conclusions AF was observed in almost half of patients with ICM and symptomatic HF. One‐fourth of the patients had new onset AF and a higher rate of HF events compared with patients without AF. AF incidence was similar in patients with preserved and reduced LVEF.

Background: Subcutaneous insertable cardiac monitors (ICM) have the capability to detect tachycardia (tachy) which are occasionally ventricular tachycardia and fibrillation (VT/VF). Objective: We investigated the incidence of spontaneous VT/VF in patients (pts) implanted with an ICM and clinical history (Hx) of heart failure (HF) with reduced or preserved left ventricular ejection fraction (LVEF). Methods: Pts with Hx of HF admissions who were implanted with an ICM were identified from the aggregated and de-identified Optum ® electronic health record (EHR) database during 2007-2021. The ICM collected data were merged with EHR data to create a de-identified database of real-world patients. Pts were included if they had ≥180 days of device follow-up. ICMs detect tachy if 30 of 40 recent intervals are shorter than 260 ms or if 16 consecutive intervals are shorter than tachy interval (nominally 340 ms) that is adjusted with age. Tachy episodes were first classified as VT/VF, SVT, or oversensing using an artificial intelligence (AI) model that was pre-trained using over 50K manually adjudicated ICM detected tachy episodes. If the AI model output probability for VT/VF was greater than 0.2, then those episodes were manually adjudicated for true incidence of non-induced spontaneous VT/VF. The Kaplan-Meier incidence curves for VT/VF incidence are reported as a function of reduced vs preserved ejection fraction. Results: A total of 1020 ICM pts with Hx of HF admission were identified from the real-world dataset. In 889 pts (87%) with available LVEF, 394 (44%) had EF<50%, and 495 (56%) had EF≥50%. In 296 pts (29%) with available NYHA class, 13%, 43%, 38%, 6% were class I, II, III, and IV respectively. Pts had an avg. age of 68±13 yrs with 52% being males and Hx of hypertension in 95%, diabetes in 56%, coronary artery disease in 75%, atrial fibrillation in 57%, stroke/TIA in 51%, and renal dysfunction in 53%. A total of 911 pts with an average follow-up of 25.8 months were included. A total of 90 tachy episodes (41 pts) were adjudicated as true VT/VF. Incidence of true VT/VF, as detected by an ICM over 36 months of follow-up, was estimated to be 5.6% with VT/VF incidence being 8.2% vs 3.8% in HF pts with reduced versus preserved LVEF (Figure). Conclusion: Incidence of VT/VF over 3 years of follow-up was estimated to be more than 5% in pts with ICM and Hx of HF events. VT/VF incidence was higher in HF pts with reduced versus preserved LVEF in this real-world cohort.

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.

Abstract Aims The aim of the Mid‐Q Response study is to test the hypothesis that adaptive preferential left ventricular‐only pacing with the AdaptivCRT algorithm has superior clinical outcomes compared to conventional cardiac resynchronization therapy (CRT) in heart failure (HF) patients with moderately wide QRS duration (≥120 ms and <150 ms), left bundle branch block (LBBB), and normal atrioventricular (AV) conduction (PR interval ≤200 ms). Methods This prospective, multi‐center, randomized, controlled, clinical study is being conducted at approximately 60 centers in Asia. Following enrollment and baseline assessment, eligible patients are implanted with a CRT system equipped with the AdaptivCRT algorithm and are randomly assigned in a 1:1 ratio to have AdaptivCRT ON (Adaptive Bi‐V and LV pacing) or AdaptivCRT OFF (Nonadaptive CRT). A minimum of 220 randomized patients are required for analysis of the primary endpoint, clinical composite score (CCS) at 6 months post‐implant. The secondary and ancillary endpoints are all‐cause and cardiovascular death, hospitalizations for worsening HF, New York Heart Association (NYHA) class, Kansas City Cardiomyopathy Questionnaire (KCCQ), atrial fibrillation (AF), and cardiovascular adverse events at 6 or 12 months. Conclusion The Mid‐Q Response study is expected to provide additional evidence on the incremental benefit of the AdaptivCRT algorithm among Asian HF patients with normal AV conduction, moderately wide QRS, and LBBB undergoing CRT implant.

AIMS:Sudden cardiac death (SCD) continues to be a devastating complication amongst survivors of myocardial infarction (MI). Mortality is high in the initial months after MI. The aims of the INSPIRE-ELR study were to assess the proportion of patients with significant arrhythmias early after MI and the association with mortality during 12 months of follow-up.METHODS:The study included 249 patients within 14 days after MI with left ventricular ejection fraction (LVEF) ≤35% at discharge in 11 hospitals in India. Patients received a wearable external loop recorder (ELR) 5 ± 3 days after MI to monitor arrhythmias for 7 days.RESULTS:Patients were predominantly male (86%) with a mean age of 56 ± 12 years. In 82%, reperfusion had been done and all received standard of care cardiovascular medications at discharge. LVEF was 32.2 ± 3.9%, measured 5.1 ± 3.0 days after MI. Of the 233 patients who completed monitoring (7.1 ± 1.5 days), 81 (35%) experienced significant arrhythmias, including Ventricular Tachycardia/Fibrillation (VT/VF): 10 (4.3%); frequent Premature Ventricular Contractions (PVCs): 65 (28%); Atrial Fibrillation (AF): 8 (3.4%); chronic atrial flutter: 4 (1.7%); 2nd or 3rd degree Atrioventricular (AV) block: 4 (1.7%); and symptomatic bradycardia: 8 (3.4%). In total, 26 patients died. Mortality was higher in patients with clinically significant arrhythmia (at 12 months: 23.6% vs 4.8% with 19 vs 7 deaths, hazard ratio (HR) = 5.5, 95% confidence interval (CI) 2.3 to 13.0, p < 0.0001). Excluding 7 deaths during ELR monitoring, HR = 4.5, p < 0.001.CONCLUSION:ELR applied in patients with acute MI and LV dysfunction at the time of discharge identifies patients with high mortality risk.

Background: Patients with inherited arrhythmogenic diseases (IADs) are often prescribed preventative implantable cardioverter-defibrillators (ICDs) to manage their increased sudden cardiac arrest risk. However, it has been suggested that ICDs in IAD patients may come with additional risk. We aimed to leverage the PainFree SmartShock Technology dataset to compare inappropriate therapies, appropriate therapies, mortality, and complications in patients with and without IAD. Methods: This retrospective analysis included extracted, physician-adjudicated, arrhythmic episodes from ICD devices. The incidence of arrhythmic events was estimated with the Kaplan-Meier method using the log-rank test. Cox proportional hazards regression was used to estimate hazard ratios (HRs) with their 95% confidence intervals (CIs). Results: Of the 1699 ICD patients, 77 patients (4.5%) had IAD. Incidence of inappropriate shock was similar in both patients with (3.2% at 24 months) and without (3.8% at 24 months) IAD (HR: 0.80, CI: 0.19-3.30, p = 0.76). In a multivariable analysis IAD was not significantly associated with reduced mortality (HR: 0.64, CI: 0.08-4.80, p = 0.66). The rates of complications were numerically lower in patients with IAD vs without (8.8% vs 9.6% at 24 months respectively), but not statistically significant (HR: 0.83, CI: 0.20-3.38, p = 0.79). Conclusions: IAD patients showed a very low annual rate of inappropriate therapy. This suggests that newer algorithms, such as the SST algorithm, are equally good at identifying and treating life-threatening arrhythmias in patients regardless of whether they have IAD.

Introduction: Heart failure hospitalization (HFH) is common, but it is also potentially preventable. The TriageHF risk score is an implantable cardiac device feature that uses data from up to 9 physiological parameters to classify patients as low, medium, or high risk of HFH in the next 30-days. Aim: To evaluate a remote management heart failure (HF) care pathway (“TriageHF-Plus”) that combines the TriageHF risk score with a structured telephone-based remote clinical patient assessment, by comparing rates of non-elective hospitalizations experienced by patients receiving TriageHF-Plus in a real-world clinical setting to those observed in patients receiving Standard of Care (SoC). Methods: Between Sept 2019 - Sept 2020, 415 patients with TriageHF compatible ICD or CRT devices were prospectively recruited from 3 UK hospitals. Once enrolled, all high risk TriageHF episodes were managed via the TriageHF-Plus pathway; these patients received a structured telephone assessment to assess for both HF and non-HF-related acute issues. Rates of non-elective hospitalizations observed following enrollment in the TriageHF-Plus cohort were compared with those observed in an unselected control cohort of HF patients with CIEDs receiving SoC (n=435) between Jan 2017 - Dec 2018. Results: Patient demographics and hospitalization data are presented in the Table. Nearly all patients in the TriageHF-Plus cohort had HF (91.9%) and the majority (77.8%) had a CRT device. In TriageHF-Plus, there were 135 unplanned all-cause hospitalizations, compared with 358 in SoC; and rates per patient year for all-cause (0.41 vs 0.57, p=0.001), cardiovascular (0.14 vs 0.29, p=0.037) and heart failure (0.02 vs 0.07, p=0.003) hospitalizations were all significantly lower in the TriageHF-Plus cohort. Conclusions: In a population of predominantly HF patients with CIEDs, the TriageHF-Plus pathway reduced rates of unplanned hospitalizations compared with SoC, with the greatest reduction observed in HFH.