EMBLEM™ MRI S-ICD System

Subcutaneous Implantable Defibrillator

Diagram of chest with Modular CRM system (mCRM).

MODULAR ATP Trial: Evaluating safety, effectiveness and performance of the Modular CRM (mCRM™) System and EMPOWER™ Leadless Pacemaker (LP)

Study overview

The pivotal MODULAR ATP trial is the basis for the commercialization of the industry's first Modular CRM system (mCRM) that consists of an entirely subcutaneous ICD (S-ICD) and the EMPOWER Leadless Pacemaker (LP).^1,2*

The components of the mCRM system are designed to work together wirelessly to coordinate intracardiac antitachycardia pacing (ATP) therapy, provide VVIR pacing and prevent sudden cardiac death² without the risk of leads in the heart^3-5 or under the sternum.^6,7

Boston Scientific EMBLEM MRI S-ICD A219.

Study design

The MODULAR ATP trial is a prospective, non-randomized, single arm, global study to demonstrate the safety, performance and effectiveness of the mCRM System and the EMPOWER LP and utilized performance goals to demonstrate these primary and secondary outcomes. In addition to evaluating the safety of the EMPOWER LP System, the MODULAR ATP trial evaluated the ability of the EMBLEM S-ICD to successfully communicate a wireless request to the EMPOWER LP to deliver intracardiac ATP.^1,** Specific testing was also conducted to determine the performance and effectiveness of the EMPOWER LP to function as a standalone VVIR pacemaker.^2,†

* The EMPOWER leadless pacemaker and mCRM system will pursue FDA approval in 2025. Caution: Investigational Device. Limited by US law to investigational use only. Not available for sale.
** The mCRM wireless communication is inductive, one-way communication from the S-ICD to the LP to request ATP delivery. Communication testing, which assesed pass/fail of communication at the programmed S-ICD Telemetry Setting, was required at 6-month visit in 4 body postures. The test had to pass in >88% of communication attempts, across all postures, to be defined as successful.
† Rate-response results will be reported in a future publication.

Enrollment

From July 2021 through January 2024, 293 patients were enrolled at 38 centers. The study design included a pre-specified early analysis of the safety endpoint once 134 patients were implanted with the EMBLEM S-ICD and EMPOWER LP System and followed for 6 months. Because of variability in the 6-month follow up appointments, 162 patients were in this group for this early analysis of the safety endpoint. The mean age of this group was 60 years with a mean EF of 33%. 61% had ischemic cardiomyopathy and 54% were primary prevention patients. ^1,8

The MODULAR ATP trial enrolled patients with significant structural heart disease and implantation of the EMPOWER LP was successful in 100% of patients.^1,8

100% EMPOWER LP implant success. Patients with significant structural heart disease were enrolled.

Results

With 162 patients implanted, the mCRM System achieved all pre-specified safety and effectiveness 6-month endpoints from the MODULAR ATP trial.¹ These results demonstrated the safety profile of the EMPOWER LP system.¹

Major complication-free rate of 97.5%. Communication testing success rate of 98.8%. Pacing capture threshold of 97.4%.

Intracardiac ATP

The EMPOWER LP is designed to deliver intracardiac ATP and brady pacing therapy that should not lead to pain or discomfort in contrast to extracardiac pacing.^1,8,9 ATP conversion success rate was 61.3% and no patient in the MODULAR ATP trial requested leadless pacemaker therapy inactivation due to feelings of pain or discomfort.^1,8,‡

‡ ATP success rate defined as terminating ventricular arrhythmia.

EMPOWER LP, designed to deliver intracardiac ATP and brady pacing therapy.

Video: mCRM System Tachycardia Therapy: S-ICD and Leadless Pacemaker deliver ATP.

Designed for the future of personalized patient care

Upon the EMPOWER LP and mCRM^TM system receiving FDA approval, EMPOWER will be the first and only LP designed to be a standalone VVIR pacemaker that is compatible with all existing EMBLEM^TM S-ICD devices as part of the mCRM system. The mCRM system is designed to deliver painless intracardiac ATP and/or brady pacing.²

Should patients currently implanted with an EMBLEM S-ICD device develop a need for ATP and/or bradycardia pacing, an upgrade pathway will be available once the EMPOWER LP and mCRM system receive FDA approval.²

The mCRM system is designed to provide upgrade pathways regardless if the EMBLEM S-ICD or EMPOWER LP is implanted first, providing physicians flexibility to tailor therapy to the individual patient’s needs.²

EMBLEM s-ICD A209 and A219 Systems, and EMPOWER Leadless Pacemaker, with the word

The New England Journal of Medicine article:

A Modular Communicative Leadless Pacing–Defibrillator System

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Pacing Performance of EMPOWER™ LP

Data from the 2024 ESC (European Society of Cardiology) late-breaking clinical trials highlight the performance of the EMPOWER LP* as a standalone VVIR leadless pacemaker. In this study, 100% implant success was achieved across the entire cohort (n=293), with chronic pacing thresholds recorded at 6 months (n=183).¹⁰ These findings are consistent with previous results.¹

APPRAISE ATP Trial, about 2,600 patients.

Pacing parameters¹⁰

EMPOWER has consistent, stable pacing performance over time:

Thresholds < 0.6 ± 0.5 V
Sensed amplitude > 14 ± 6 V
Pacing impedance ~ 700 ± 130 Ω

Rate response¹⁰

The EMPOWER LP rate response is effective in adapting to patient’s physical activity levels

Holter monitor sub-study¹⁰

No oversensed beats, no loss of capture, max 1 undersensed event/patient

Prof. Knops 2024 HRS presentation

Video: First Results of the Modular ATP Trial.

APPRAISE ATP: Assessment of primary prevention patients receiving an ICD-systematic evaluation of ATP

Study design and overview¹¹

The APPRAISE ATP trial was a prospective, randomized, global, multicenter clinical trial to understand the role of ATP in primary prevention (PP) patients currently indicated for ICD therapy.

The objective of the trial was to determine if standard therapy (ATP prior to shock) is clinically equivalent to No ATP prior to shock when combined with contemporary programming in primary prevention TV-ICD indicated patients. The trial was designed to determine if programming ATP OFF in Zone 2 in PP patients is equivalent to programming ATP ON by measuring time to first all-cause shock.

Enrollment and randomization^11,12

The APPRAISE ATP trial is the largest head-to-head trial of ATP in primary prevention patients. The trial enrolled 2,626 primary prevention ICD indicated patients from 134 centers in North America, Europe, and Asia.¹² Patients received a single- or dual-chamber transvenous ICD (TV-ICD) and 2,595 were randomized 1:1 to different therapy programming in an equivalence study design with sequential superiority analysis of each arm.

PP ICD indicated patients received a Boston Scientific de novo single or dual-chamber TV-ICD.

Results¹²

The APPRAISE ATP trial demonstrated superiority with a 28% relative risk reduction in time to first all-cause shock for the ATP ON arm compared to the ATP OFF arm (Log-rank P-value=0.005). This represents an absolute all-cause shock reduction in 1% of PP ICD indicated patients per year.

There was a significant difference throughout follow up (p=0.005). The percentage of patients free from all-cause shocks at one year was 95.7% for ATP-plus-shock arm vs 94.7% for the shock-only arm.

At five years, the percent of patients free from all-cause shocks was 85.4% for the ATP-plus-shock arm vs 80.6% for the shock-only arm.¹²

Data showing 28% relative risk reduction.

This represents an absolute all-cause shock reduction in 1% of primary prevention ICD indicated patients per year (Log-rank P-value=0.005).^12,13

Inappropriate shock rates low in both arms

Inappropriate shock rates were low in both TV-ICD programming arms due to the use of guideline recommended programming for PP patients.^12,14 While the overall difference between arms was significant (p=0.033), the absolute differences at 1 year and 5 years were 0.3% and 2.2% of patients, respectively.¹²

Percent of TV-ICD patients free from inappropriate shocks at 1 year and 5 years in each arm.

Full follow-up results

§ Defined as all shocks over full follow-up period per 100 patients.

The importance of shared decision making

With an absolute all-cause shock reduction in 1% of PP patients with a TV-ICD per year,^12,13 this benefit of ATP should be discussed with PP patients eligible for an S-ICD during shared decision making and should also be compared to the lifetime risk of having a lead in the heart with a TV-ICD.^3-5,15 More data and time is needed to determine the risks associated with a substernal ICD lead.^6,7

1% absolute shock reduction per year vs. lifetime risks of lead in the heart.

Journal of the American Medical Association:

Assessment of Antitachycardia Pacing in Primary Prevention Patients