EMBLEM™ MRI S-ICD System

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

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

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

MODULAR ATP 12-month trial data 

• The EMPOWER LP System demonstrated a consistent complication free rate of 97.2% at 12 months following implant (n = 286).¹⁶   
• For patients who needed ATP in the MODULAR ATP trial, the mCRM System devices and therapy demonstrated effectiveness to pace-terminate VA in 65.4% of episodes, resulting in painless ATP⁸ and shock-free arrhythmia termination in almost half of discrete VA episodes.¹⁷ 
• The EMPOWER LP withheld** ATP therapy in 19% of treated episodes; 43% of which were inappropriately S-ICD sensed events.^17,18 
• These data demonstrate that the mCRM System reduced the shock burden** by an estimated 56% within the MODULAR ATP patient population compared to an S-ICD in isolation.¹⁸

Pacing Performance of EMPOWER™ LP

Prof. Knops 2024 HRS presentation

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.

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

Inappropriate shock rates low in both arms

Full follow-up results

The importance of shared decision making

Dr. Schuger 2024 HRS presentation

Future upgrade pathway with the Modular CRM (mCRM™) System*

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

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

* 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. 

** Shocks were avoided by (1) delivering ATP OR (2) LP withholding ATP and the S-ICD transitioning to a conservative sensing strategy. ¹⁸