World's only contractility sensor for automatic CRT optimization

Healthcare Professionals Cardiac Rhythm Management Cardiac Rhythm Management Products CRT devices SonR™


SonR CRT-D + SonRtipTM Atrial Lead

The Respond CRT system is a unique combination of a cardiac contractility sensor with an advanced optimization algorithm.

  • Continuous measurement of the contractility of the heart allowing for automatic optimization of AV and VV intervals.
  • Weekly optimization at rest and exercise.
  • 35% risk reduction in HF hospitalization.1
Click here to download the infographic


The SonR sensor consists of a micro-accelerometer embedded in the tip of the SonRtip atrial lead.

SonR measures the vibrations generated by the myocardium during cardiac contractions, which are correlated to LV dP/dt max.2,3,4


SonR sensor continuously measures the contractility of the heart allowing for automatic optimization of AV and VV intervals. Optimization is performed on a weekly basis both at rest and during exercise.

This allows for cardiac resynchronization therapy to be continuously adapted to the individual needs of each patient.


SonR optimization is as effective as echo-guided optimization.

The RESPOND-CRT trial successfully met its primary endpoint demonstrating that automatic AV & VV optimization with SonR technology is safe and as effective as best practice AV and VV optimization using echocardiography.

75% of clinical responders in the SonR group versus 70% in the control group (p<0.001) at 12 months.

SonRtip proven to be safe.

The rate of successful implantation of the SonRtip was 99.8% and the freedom from acute and chronic complications was 98.5% and 99.8%, respectively.

35% risk reduction in heart failure hospitalization.

The RESPOND-CRT landmark trial revealed that sensor-based CRT optimization with SonR is associated with a 35% reduced risk in heart failure hospitalization.

Visit the RESPOND-CRT website for more information

This feature is not available for sale or distribution in the USA. For further information on product availability, please contact your local representative.

Click here to download the study
SonR™ Graph SONR 1 3

SonR feature is not available in the USA.

Related products: Platinium™ 4LV SonR™ CRT-D


  1. Brugada J, Delnoy PP, Brachmann J, Reynolds D, Padeletti L, Noelker G, Kantipudi C, Rubin Lopez JM, Dichtl W, Borri-Brunetto A, Verhees L, Ritter P, Singh JP; RESPOND CRT Investigators. Contractility sensor-guided optimization of cardiac resynchronization therapy: results from the RESPOND-CRT trial. Eur Heart J. 2017 Mar 7;38(10):730-738.
  2. Rickards AF, Bombardini T, Corbucci G, Plicchi G. An implantable intracardiac accelerometer for monitoring myocardial contractility. The Multicenter PEA Study Group. Pacing Clin Electrophysiol. 1996 Dec;19(12 Pt 1):2066-71.
  3. Bongiorni MG, Soldati E, Arena G, Quirino G, Vernazza F., Bernascoi B, Garberoglio B. Is local myocardial contractility related to endocardial acceleration signals detected by a transvenous pacing lead? Pacing Clin Electrophysiol. 1996 Nov;19:1682-88.
  4. Bordachar P, Garrigue S, Ritter P, Ploux S, Labrousse L, Casset C, Haissaguerre M, Dos Santos P. Contributions of a hemodynamic sensor embedded in an atrial lead in a porcine model. J Cardiovasc Electrophysiol. 2011 May;22(5):579-83.