AdaptivCRT Education and Clinical Evidence

Clinical evidence shows that AdaptivCRT has helped to increase CRT response rate, reduce unnecessary right ventricular pacing, and improve clinical outcomes for patients with normal AV conduction.3-6 In addition, by promoting intrinsic RV conduction, AdaptivCRT reduces RV pacing and increases device longevity for patients with normal conduction.3-6


Dynamic, Physiologic CRT

AdaptivCRT™ continuously and dynamically optimizes the cardiac resynchronization therapy (CRT) pacing method and AV/VV delays according to their conduction status and level of activity every minute.1,* It leverages a patient’s intrinsic RV conduction when possible while still maintaining CRT. AdaptivCRT comprises two pacing operations: Adaptive LV and Adaptive BiV. 

The following three steps describe the general operation of the AdaptivCRT algorithm1-2 

  1. Assess intrinsic conduction every minute and determine if a patient’s AV interval is normal or prolonged.
  2. Based on that assessment, determine the pacing method to be either Adaptive LV, for normal AV intervals and heart rates < 100 bpm, or Adaptive BiV, for prolonged AV intervals and elevated heart rates.
  3. Optimize timing - For Adaptive LV pacing, the algorithm will determine when to pre-pace the LV to synchronize with the intrinsic RV activation. For Adaptive BiV pacing, the AV/VV delays will be optimized based on AV interval, P wave and QRS waveform width measurements.

AdaptivCRT Clinical Evidence Overview with Aleksandre Sambelashvili

AdaptivCRT Trial Results

The AdaptivCRT trial compared AdaptivCRT to BiV pacing with comprehensive echo optimization of AV and VV delays.2-6  In this video, Medtronic Scientist, Dr. Alexsandre Sambelashvili provides an overview of the AdaptivCRT clinical trial results

There were 522 patients enrolled in this multi-center, prospective, randomized, double blind study. Patients were randomized 2:1 AdaptivCRT versus full echo optimization and followed for twelve months. The trial met its primary endpoints, showing that CRT patients with AdaptivCRT performed just as well or better as patients with consistently applied echocardiographic optimization.While the results are non-inferior, the improvement in Packer Clinical Composite Score for the AdaptivCRT arm is significantly higher than historical CRT trials such as MIRACLE, MIRACLE ICD, InSync III Marquis and PROSPECT.3

Clinical evidence shows that AdaptivCRT improves patient outcomes, compared to echo-optimized CRT,2-7 including:

  • 12% absolute improvement in CRT Response in patients with normal AV conduction.*
  • 44% reduction in unnecessary right ventricular pacing at six months.
  • 46% reduction in device-detected AF.
  • 59% odds reduction of 30-Day HF readmission.**
  • Patients who received > 50% of Adaptive LV pacing had a lower rate of death or HF hospitalizations compared to patients who received <50% Adaptive LV pacing. 
* Percentage of patients improved in Packer Clinical Composite Score at 6-month follow-up. Clinical Composite Score is a composite measure of mortality, HF hospitalization, and symptomatic changes.
48 or more continuous hours of atrial fibrillation. 
** Readmissions following a HF hospitalization.

Top Questions on AdaptivCRT Answered by Principal Scientist

Medtronic Principal Scientist Aleksandre Sambelashvili addresses several questions on the Adaptive CRT in this series of videos.

  1. Can CRT-indicated patients with prolonged AV intervals benefit from AdaptivCRT?
  2. Why was Packer's Clinical Composite Score chosen as one of the primary endpoints of the Adaptive CRT trial?
  3. How was echo-cardiographic optimization done in the control arm of the Adaptive CRT trial?
  4. How does RV lead placement affect Adaptive CRT settings?
  5. How do you measure the P-wave width, and is there evidence on the accuracy of the P-wave width measurements?
  6. What is the evidence behind VV Optimization during Adaptive BiV pacing?
  7. Will AdaptivCRT provide the narrowest QRS? Is this important?

*Note: For Amplia MRI CRT-D device models, AdaptivCRT is nominally set to “Adaptive BiV and LV.” The normal AV conduction boundaries are extended to 270/220 ms (PAV/SAV) and the V-V delay during Adaptive BiV operation is restricted to LV pacing first. 

This webpage is intended only for users in markets where Medtronic products and therapies are approved or available for use as indicated within the respective product manuals. Content on specific Medtronic products and therapies is not intended for users in markets that do not have authorization for use.



Medtronic VivaTM Quad XT CRT-D Clinician Manual, Medtronic, Inc., Minneapolis, MN, USA
Krum, et al. A novel algorithm for individualized cardiac resynchronization therapy: rationale and design of the adaptive cardiac resynchronization therapy trial. American Heart Journal 2012; 163: 747-752.
Martin DO, Lemke B, Birnie D, et al. Investigation of a novel algorithm for synchronized left ventricular pacing and ambulatory optimization of cardiac resynchronization therapy: results of the adaptive CRT trial. Heart Rhythm. 2012; 9(11): 1807-1814.
Birnie D. et al., Clinical outcomes with synchronized left-ventricular pacing: analysis of the adaptive CRT trial. Heart Rhythm 2013; 10(9): 1368-1374.
5  Martin D, Lemke B, Aonuma K, et al. Clinical outcomes with adaptive cardiac resynchronization therapy: long-term outcomes of the  adaptive CRT trial. HFSA Late Breakers. September 23, 2013.
6 Singh JP, Abraham WT, Chung ES, et al.  Clinical response with adaptive CRT algorithm compared with CRT with echocardiography-optimized atrioventricular delay:  a retrospective analysis of multicentre trials.  Europace 2013; 15(11): 1622-1628. 
7 Starling RC, Krum H, Bril S, et al. Impact of a novel adaptive optimization algorithm on 30-day readmisions: evidence from the Adaptive CRT trial. JACC: Heart Failure 2015; doi:10.1016/j.jchf.2015.03.001
8 BirnieD. et al., Impact of a Novel Adaptive Algorithm on 30-Day Readmissions:Evidence From the AdaptivCRT Trial. Heart Rhythm. 2013;10:1368-1374.


Last updated: 
08 Jun 2016