Clinical Evidence

ClinicalEVIDENCE Newsletter

Newsletter #3 – July 2023

ClinicalEVIDENCE newsletter #3 – July 2023

Welcome to the ClinicalEVIDENCE newsletter, your go to source for the latest clinical data on heart diseases, diagnostics, and monitoring.

Our aim is to provide you with cutting-edge information that will keep you up-to-date on the most recent advancements in the field of heart failure management.

In this issue, we are excited to have the opportunity to share the key messages from the two latest publications on HeartLogicᵀᴹ.

We will also provide you with the highlights of the abstracts presented at the most important congresses earlier this year.


HeartLogic Publications

Recently two new interesting publications on HeartLogic have come to light, confirming once again the algorithm’s performance and advantages of its use in clinical practice.

In the following sections we will outline the most important key messages coming from these publications.


Clinical Benefit of HeartLogic

In May Dr. Feijen et al (Leiden University Medical Centre, Leiden, The Netherland) published on Journal of Cardiac Failure an analysis about the clinical benefit provided by the use of HeartLogic on top of standard care and device telemonitoring in HF patients.

“Fewer worsening heart failure events with HeartLogicᵀᴹ on top of standard of care: a propensity-matched cohort analysis.”

Methods and Endpoint:

A multicenter retrospective propensity-matched cohort analysis was performed in HF patients with and ICD and compared HeartLogic to conventional telemonitoring in term of HF events.

  • Primary endpoint was the number of worsening HF events defined as a composite of hospital admission for HF and an unplanned ambulatory HF visit (lifestyle advice and/or diuretic therapy increase)
  • Secondary endpoints were the number of HF hospitalizations and the scheduled ambulatory HF visits requiring actions.


Propensity score matching yielded 127  matched pairs with highly similar baseline characteristics. All patients were followed-up for 365 days.

  • The median number of worsening HF events was 1 (IQR 0-3) in HeartLogic group and 2 (IQR 0-4) in control group (p=0.004). (Panel a)
  • There was nonsignificant trend toward a lower number of HF hospitalizations in the HeartLogic group (P=0.096).
  • The number of HF hospitalization days was significantly higher in the control group, with 8 (IQR 5-12) hospitalization days compared to 5 (IQR2-7) days in the HeartLogic group (P=0.025). (Panel b)
  • There was a significantly higher number of ambulatory visits for intensifying diuretics in the control group (2; IQR0 - 3) compared to 1 (IQR0 - 2) in the HeartLogic group (P=0.0001).


  • The HeartLogic algorithm can detect impending fluid retention.
  • Activating HeartLogic is associated with less worsening heart failure events, shorter hospitalization duration and less ambulatory visits as summarized in the graphical abstract.

Key take-aways:

Integrating the HeartLogic algorithm into a well-equipped heart failure care pathway on top of standard care is associated with clinical benefits characterized by fewer worsening HF events and shorter hospitalizations related to fluid retention.

Performance of HeartLogic Algorithm

At the beginning of June, the latest original publication on HeartLogic has been published on ESC Heart Failure Journal by Dr. Santobuono et al. (University of Bari, Bari, Italy).

“Performance of a multisensor implantable defibrillator algorithm for heart failure monitoring related to co-morbidities”

This analysis was intended to fill the lack of data on the HeartLogic performance in non-CRT-D patients, not considered in MultiSENSE study) and in the presence of cardiovascular and non-cardiovascular comorbidities.

Methods and Endpoint:

568 consecutive HF patient with reduced LVEF who had received an ICD or CRT-D device endowed with the HeartLogic algorithm and followed up in accordance with the standard practice of the participating centers were include in the analysis.

The objectives of the study are:

  • to compare the incidence of HeartLogic alerts between CRT and non-CRT patients;
  • to evaluate the frequency of HeartLogic alerts in relation to the presence of co-morbidities;
  • to investigate the investigated the impact of the presence of co-morbidities on the performance of the HeartLogic Index.

The study endpoints consisted of cardiovascular hospitalizations requiring at least one overnight stay and the combination of cardiovascular hospitalizations and death.


During a median follow-up of 26 months 1200 HeartLogic alerts (0.71 alerts/patient-year) occurred in 370 patients and overall, the time IN the alert state was 13% of the total observation period.

The rate of cardiovascular hospitalizations or death was 0.48/patient-year with the HeartLogic IN alert state and 0.04/patient-year OUT of alert state, with an incidence rate ratio of 13.35 (95%CI: 8.83-20.51, p<0.001).

Among patient characteristics, atrial fibrillation (AF) at implantation and chronic kidney disease (CKD) independently predicted alerts. HeartLogic alerts were not associated with CRT vs. non-CRT device implantation (HR:1.03, 95%CI:0.82-1.30, p=0.775). (Figure below)

Figure3 Figure: Kaplan-Meier analysis of time to first HL alert a) AF Vs no-AF groups; b) CKD Vs no-CKD groups; c) CRT Vs ICD groups.

After multivariate correction for CKD and AF at implantation, the time IN the HeartLogic alert state >13% was associated with the occurrence of the combined endpoint of cardiovascular hospitalization or death (HR: 2.54, 95%CI:1.61-4.01, p<0.001).

Comparing the combined index and all physiologic parameters during clinically stable periods, no differences between CRT and non-CRT patients were observed.

Some differences are retrieved among CKD and AF patients, but these differences persisted at the time of alerts (all p<0.05). In patients stratified by device type, CKD and AF, we measured significant changes of all contributing sensors (paired t-test; p<0.05) from clinically stable periods to the time of alert. 


  • The burden of HeartLogic alerts appears similar between CRT and non-CRT patients, while patients with AF and CKD seem more exposed to alerts.
  • The ability of the HeartLogic algorithm to identify periods of significantly increased risk of clinical events was confirmed both in the overall population and in patients stratified by device type, CKD and AF.
  • At multivariate analysis, the time IN the HeartLogic alert state >13% was associated with the occurrence of cardiovascular hospitalization or death.

Key take-aways:

  • AF at implantation and CKD independently predict HeartLogic alerts.
  • HeartLogic algorithm identifies patients during periods of increased risk of clinical events regardless of the type of device, AF or CKD.

Congress Season 2023

In the past months, some Congresses of most important cardiac societies took place, bringing to light a large amount of new scientific evidence.

Among the vast number of new findings presented, we’d like to delve into the key messages regarding HeartLogic and Remote support that have been presented at EHRA and ESC-HF congresses.

Congress Season 2023 – EHRA 2023


The scientific program of EHRA Congress 2023 (Barcelona, 16 – 18 April) included the participation of various experts from different cardiac field, such as heart failure, device therapy and diagnosis, and cardiac pacing.

We selected three poster presented during EHRA Congress:

  • two about HeartLogic feature
  • one about Remote support.

“Prediction of all-cause mortality using a multisensory implantable defibrillator algorithm for HF monitoring”

has been presented by Dr. D’Onofrio (Monaldi Hospital, Naples, Italy) as Moderated Poster.

This analysis evaluated whether remotely monitored data from HeartLogic could be used to identify patients at high risk for mortality.

The study endpoint was death due to any cause.

The HeartLogic was activated in 568 patients and during a median follow-up of 26 months 55 patients died (46 in the group with alerts), 33 deaths were from cardiovascular causes.

The rate of death during IN-alert state periods was 0.25 death/patient-year, while the rate during OUT of the alert state periods was 0.02 death/patient-year.

The occurrence of any alert episode was associated with an increased risk of death [hazard ratio (HR): 2.08, 95% confidence interval (CI): 1.16–3.73, P = 0.039] and a time IN alert ≥20% was associated with death (HR: 4.07, 95%CI: 2.19-7.54, p<0.001).

Key take-aways:

  • This analysis demonstrated that the occurrence of HeartLogic IN-alerts is significantly associated with mortality due to any cause.
  • The rate of fatal events is substantially higher with the HeartLogic in the alert state.

The full-length paper is available on Heart Rhythm. 2023 Mar 24:S1547-5271(23)00331-4

“Combination of device-detected heart failure status and sleep-disordered breathing for the prediction of atrial fibrillation occurrence”

has been presented by Dr. Vitali (University of Ferrara, Italy) as ePoster.

This analysis explored the association between sleep apnea and the HF status using HeartLogic and the incidence of AF in patients with implantable defibrillators (ICD).

411 consecutive patients implanted with ICD o CRT-D device endowed with HeartLogic have been enrolled in the analysis and observed for a median follow-up of 26 months.

The HF status was measured by the HeartLogic Index, and the ICD-measured Respiratory Disturbance Index (RDI) was computed to identify severe SA.

The endpoints were: daily AF burden of ≥5minutes, ≥6hours and ≥23hours. 

Figure5 Time-dependent Cox model

Figure shows the time-dependent Cox model: the IN-alert HF state was independently associated with AF regardless of the daily burden threshold: HR from 2.17 for ≥5 min/day to 3.43 for ≥23 h/day (p<0.01), while the occurrence of severe SA was associated only with AF burden ≥5 min/day (hazard ratio 1.55 [95%CI:1.11-2.16], p=0.001). 

Key take-aways:

  • The occurrence of AF is independently associated with the ICD-measured HF status and with severe SA. ​
  • The coexistence of HeartLogic alerts and severe SA occurs rarely but is associated with a very high rate of AF occurrence.
The full-length paper is available on Europace (2023) 00, 1–8

“Remote support during cardiac implantable electrical device follow-up:  preliminary experience in clinical practice”

has been presented by Dr. D’Onofrio (Monaldi Hospital, Naples, Italy) as ePoster.

In this analysis, authors described the preliminary experience of remote industry employed allied professionals (IEAPs)  support using Heart Connect™ during CIED follow-up in clinical practice.

The Heart Connect™ application is a data-sharing system intended to provide physicians with the means to establish an online meeting and share the display of the LATITUDE™ Programmer (Boston Scientific) with IEAPs in a remote location (Figure).

The Heart Connect software was downloaded on the programmer and network connection was established. After system setup, the staff was trained on how to use the application, and online meetings were established with IEAPs of the Remote Clinical Support team during consecutive CIED follow-up visits.

Figure6 Heart Connect on LATITUDE™ Programmer

During observation period a total of 34 follow-up visits were performed.

The remote connection was successfully established in all cases and the communication remained stable for the entire duration of all visits, except for 2 cases in which a loss of connection occurred (not restored in 1 case). 

The sound and video quality during two-way communication were rated good or excellent in 31 (91%) cases.

Routine CIED checks were performed during the visits and programming changes were done during 7 (21%) visits (pacing and sensing parameters, tachycardia detection and therapies).

The remote support allowed to successfully complete the visit in 33 (97%) cases, without requiring additional medical or technical support. In all these cases, the support was judged to be equally effective compared to the on-site support, without causing delays or organizational difficulties.

Key take-aways:

  • Remote support during CIED follow-up using Heart Connect seems feasible, effective and well accepted. 

Congress Season 2023 – ESC-HF 2023


The annual congress of the Heart Failure Association of the ESC (ESC-HF 2023) took place in Prague & online from 20 to 23 of May.

It covers the entire spectrum of heart failure, from prevention to diagnosis and treatment with new research presentation, symposia, interactive events and great discussions. 

During this congress original data from RE-HEART Spanish registry has been presented by Dr De Juan Bagudá (Hospital Universitario 12 de Octubre, Madrid, Spain): a Rapid Fire presentation and an ePoster.

“Performance of a multiparametric implantable cardioverter-defibrillator algorithm for heart failure risk stratification and management: the multicentric Spanish RE-HEART Registry”

has been presented as ePoster.

The aim of this analysis was to evaluate the risk stratification ability of the algorithm in ICD and CRT-D patients in clinical practice.

392 patients were enrolled in 19 centers and followed for a median observation period of 17  months.

The index crossed the threshold value 436 times (0.78 alerts/patient-year) in 195 patients and the time in the alert state was 10% of the total observation period.

The rate of HF hospitalizations or death is:

  • 1.39 events/patient-year  IN alert state.
  • 0.05 events/patient-year out of alert state (p<0.001). 

The rate of HF admissions in an outpatient setting is:

  • 1.54 events/patient-year IN alert state.
  • 0.02 events/patient-year OUT of the alert state (p<0.001). 
  • 242 (56%) alerts were deemed clinically meaningful, being associated with HF events, signs or symptoms of HF and the corrective therapies delivered or other conditions (e.g., hospital admissions for non-HF conditions, arrhythmias’ onset, changes in drug or dietary regimen).
  • 194 (44%) alerts were unexplained (0.34 alerts/patient-year).

Key take-aways:

  • HeartLogic identified patients during periods of significantly increased risk of HF events.
  • The use of the algorithm allowed relevant clinical conditions to be identified remotely, with a low rate of unexplained alerts.

“Clinical impact of remote heart failure management using a multiparametric implantable cardioverter-defibrillator alert: the multicentric Spanish RE-HEART Registry”

has been presented as Rapid Fire presentation.

Authors evaluated the impact of the RE-HEART standardized follow-up protocol implemented by nursing staff and based on remote management of alerts on the clinical outcome of ICD and CRT-D patients.

The standardized protocol used by all centers has been already presented in a previous publication¹.

Figure8 RE-HEART standardized protocol
  • Primary endpoints: HF hospitalizations or deaths.
  • Secondary endpoints: HF outpatient visits.

HF events occurred during the 12-month period before the adoption of the protocol were compared with those occurred in the following 12 months.

The HeartLogic algorithm was activated in 392 HF patients who had received an ICD or CRT-D device.

The total number of patients that experienced HF events (hospitalizations or deaths  and outpatient visit for HF) for 12 months pre- and post- adoption of the RE-HEART management protocol are reported in the graph.

After the adoption of the RE-HEART protocol a significant reduction in HF hospitalizations (from 0.39±0.89 (in 22% of patients) to 0.18±0.57 (in 11% of patients)) and outpatient visits (from 0.47±1.11 (in 24% of patients) to 0.16±0.51 (in 12% of patients)) was observed.

Figure9 Number of patient with HF events

Key take-aways:

  • The adoption of the RE-HEART protocol significantly improved the clinical outcome of HF patients who had received a remotely monitored ICD or CRT-D device.
  • The adoption of the protocol allowed a prompt intervention in case of suspected worsening HF and promoted remote management.


  1. de Juan Bagudá et al. «Remote heart failure management using the HeartLogic algorithm. RE-HEART registry». Rev Esp Cardiol (Engl Ed). 2022 Sep;75(9):709-716. doi: 10.1016/j.rec.2021.09.015 
Clinical Evidence

When we challenge our impact on the environment, we advance ways to protect it.

* Estimates based on rate and mean length of stay for heart failure admissions reported in Treskes et al. (2021) and data from sustainable care pathways guidance: Inpatient bed day.7 Estimates exclude impact of non-inpatient care prior to admission (e.g., primary care support or acute medical unit management), possible surgical treatment or visitors during hospital stay.

The law restricts these devices to sale by or on the order of a physician. Indications, contraindications, warnings, and instructions for use can be found in the product labelling supplied with each device, or at Products shown for INFORMATION purposes only and may not be approved or for sale in certain countries. This material not intended for use in France. 2022 Copyright © Boston Scientific Corporation or its affiliates.  All rights reserved.