AdaptivCRT Algorithm Cardiac Device Features

Overview

The AdaptivCRT Algorithm optimizes CRT pacing every minute whether AV conduction is normal, prolonged, or blocked.

It adapts to meet the constantly changing needs of CRT patients because it responds to what he or she is doing and automatically decides when and how to pace the heart. 

The AdaptivCRT Algorithm has two different modes:

  • AdaptivCRT LV-only pacing occurs during normal AV conduction when the heart rate is less than or equal to 100 beats per minute. It also optimizes A-V timing and minimizes right ventricular (RV) pacing.
  • AdaptivCRT BiV pacing occurs during prolonged/blocked AV conduction or when the heart rate is greater than 100 beats per minute. It also optimizes A-V and V-V timing. 

Normal AV Conduction
And HR ≤ 100 bpm

ECG strip showing normal AV conduction

AdaptivCRT LV-only Pacing

Prolonged AV Conduction
Or HR > 100 bpm

ECG strip showing prolonged AV conduction

AdaptivCRT BiV-only Pacing

Clinical Evidence

Studies have shown that the most common adverse events associated with CRT therapy are lead dislodgement, diaphragmatic stimulation, coronary-sinus dissection, pocket hematoma, pneumothorax, and device-related infection.

Reduction in Mortality

The AdaptivCRT Algorithm is associated with a 29% relative reduction in mortality(after adjusting for other potential risk factors*).

Analysis Design

A total of 1,814 patients who had no reported long-standing AF history were included in the analysis. Frailty survival models were used to evaluate the potential survival benefit of the algorithm, adjusting for patient heterogeneity and center variability.

Results

Patients who received AdaptivCRT were associated with a 29% relative reduction in all-cause mortality versus conventional CRT (after adjusting for other potential risk factors*).

Total Survival AdaptivCRT versus Standard CRT

Graph showing a 29% relative reduction in all-cause morality with AdaptivCRT


*Patients who received AdaptivCRT were associated with a 29% relative reduction in all-cause mortality versus conventional CRT (after adjusting for other potential risk factors including age, gender, LVEF, NYHA class, QRS duration, AF, CAD, hypertension, AV block, and LBBB).

Improved CRT Response at 6 Months

The AdaptivCRT Algorithm showed a 12% improvement in CRT response at 6 months.†2

Objective

To examine whether synchronized left ventricular pacing resulted in better outcomes.

Study Analysis

  • Control n = 91
  • AdaptivCRT arm n = 150
  • Retrospective sub-analysis

Results

In patients with normal AV conduction, the AdaptivCRT Algorithm provided mostly synchronized LV pacing and demonstrated better clinical outcomes compared to echocardiography-optimized biventricular pacing.

12% Improvement in CRT Response for Patients with Normal AV Conduction

Graph showing a 12% improvement in CRT response with AdaptivCRT

†  Clinical Composite Score is a composite measure of mortality, HF hospitalizations, and symptomatic changes.

The AdaptivCRT Algorithm Showed a 46% Reduction in AF Risk‡§3

Objective

To compare the long-term effects of AdaptivCRT with conventional cardiac resynchronization (convCRT) therapy pacing on the incidence of AF.

Analysis Design

  • N = 472
  • Post-hoc sub-analysis

Results

Patients with AdaptivCRT had a reduced risk of AF compared with those receiving conventional CRT.

Incidence of Primary End Point

(≥ 48 consecutive hours of atrial tachycardia/atrial fibrillation)

Graph showing a 46% reduction in atrial fibrillation risk with AdaptivCRT

  Most of the reduction in AF occurred in subgroups with prolonged AV conduction at baseline and with significant left atrial reverse remodeling.

§  In patients with indicated cardiac implanted electronic devices.

The AdaptivCRT Algorithm Showed a 35% Reduction in AF Risk§4

Objective

To investigate programmed use of AdaptivCRT versus standard BiV pacing and the risk of incident continuous AF > 48 hours.

Analysis Design

44,838 patients in the Medtronic CareLink database were compared for the risk of incident continuous AF > 48 hours based on the programmed use of AdaptivCRT versus standard BiV pacing.

Results

  • In a large cohort of patients implanted with CRT-D, AdaptivCRT was associated with a reduced risk of developing AF by 35% (p < 0.0001).||
  • Patients with shorter and longer PR intervals both had lower incidence of AF with AdaptivCRT.
  • A higher percentage of LV-only pacing during AdaptivCRT was also associated with lower incidence of AF.

Incidence of Atrial Fibrillation

Graph showing a 35% reduction in atrial fibrillation risk with AdaptivCRT versus standard BiV pacing

§  In patients with indicated cardiac implanted electronic devices.

||  Kaplan-Meier methods and the log-rank test were used to compare groups’ time to first occurrence of 48 hours of AF. 48 hours of AF was defined to be 2 consecutive days of > 23 hours of AF as measured by the device.

Reduction in 30-day HF Readmission

The AdaptivCRT Algorithm showed a 59% reduction in a patient’s odds of a 30-day HF readmission.4

Objective

To investigate the impact of the Medtronic AdaptivCRT Algorithm on 30-day readmissions after heart failure and all-cause index hospitalizations.

Analysis Design

  • N = 478
  • Retrospective analysis

Results

Use of AdaptivCRT is associated with a significant reduction in the probability of HF readmissions after both HF and all-cause hospitalizations.

Kaplan-Meier Curves of Hospital Readmissions 

Graph showing a 59% reduction in a patient's odds of a 30-day heart failure readmission with AdaptivCRT

References

1

Singh JP, et al. Improved Survival With Dynamic Optimization Of CRT Pacing Using AdaptivCRT Algorithm: Analysis Of Real-world Patient Data. Presented at HRS 2018 (Abstract B-AB37 -06).

2

Birnie D, Lemke B, Aonuma K, et al. Clinical outcomes with synchronized left ventricular pacing: analysis of the adaptive CRT trial. Heart Rhythm. September 2013;10(9):1368-1374.

3

Birnie D, Hudnall H, Lemke B, et al. Continuous optimization of cardiac resynchronization therapy reduces atrial fibrillation in heart failure patients: Results of the Adaptive Cardiac Resynchronization Therapy Trial. Heart Rhythm. December 2017;14(12):1820-1825.

4

Starling RC, Krum H, Bril S, et al. Impact of a Novel Adaptive Optimization Algorithm on 30-Day Readmissions: Evidence From the Adaptive CRT Trial. JACC Heart Fail. July 2015;3(7):565-572.