![]() |
|
| 99.9%3 intrinsic conduction |
Sinus rhythm overdrive
Suppression of post extrasystolic pauses
PACs-induced acceleration
Symphony® DR 2550 in AAIsafeR mode offers a unique and comprehensive means to achieve optimal physiologic pacing. Applicable to all types of AV conduction disorders, including permanent first degree AV block, it contributes to a reduced risk of heart failure, atrial fibrillation and morbidity.
AAIsafeR is a pacing mode with real AAI architecture that constantly monitors ventricular activity, providing dual-chamber pacing in case of AV block only when needed.
Symphony® DR 2550 also offers an advanced set of diagnostic functions called AIDA+, including 7 minutes of electrocardiogram recordings.
"It’s ironic that a new pacing therapy that corrects over pacing is also the first diagnostic tool that reveals the extent to which AV block patients may also avoid unnecessary ventricular pacing."
Kenneth Ellenbogen, MD
Richmond, VA
EP Lab Digest, March 2004
Automatic storage of EGMs for all types of AV block

Symphony® DR 2550 EGMs store up to 7 episodes of AV block or ventricular pauses, including at least 1 episode for each type of AV block. In this example the device is managing 1st degree AV block by switching from AAI to DDD after 7 consecutive PR intervals >350 ms.
Prevention of atrial fibrillation
The overall duration of atrial fibrillation episodes is decreased by 30%2. Sorin Group’s 3 complementary algorithms have been shown to be effective in the presence of preserved spontaneous AV conduction.
Sinus rhythm overdrive
Suppression of post extrasystolic pauses
PACs-induced acceleration
have been shown to be effective in presence of preserved spontaneous AV conduction.
Monitoring of long-term changes in AV conduction
Histogram of AAIsafeR activity

The upper histogram shows the daily number of blocked P-waves synchronized to DDD pacing. The lower histogram shows a progressive increase in the number of mode switches that occurred in the 6 months preceding this interrogation.
"Ventricular pacing should be avoided whenever possible. The first clinical experience with AAIsafeR supports symptom-free low ventricular pacing claims. This innovative concept may become the most efficient mode for sinus node disease, brady-tachy syndrome and intermittent AV block."
Prof. G. Fröhlig
Universitätskliniken des Saarlandes
Homburg – Germany

Automatic All the Way
Allows for a simple and swift optimization of pacing functions
7 minutes of complete electrogram recordings
Automatic and comprehensive self-diagnosis of:
-Atrial and ventricular arrhythmias
-Pacemaker function
-AV conduction

When interrogating this pacemaker, the stored EGMs revealed the occurrence of 7 episodes of AV block. This episode shows pacing switch from AAI to DDD mode, using the 2nd degree AV block criterion (i.e. 3 blocked P waves within 12 atrial cycles).
Intended uses, warnings and precautions
1. Davy JM et al; Determining the optimal pacing mode to prevent ventricular pacing: SAVE R study results. Heart Rhythm; 2006;3 (Supp 5):S169, P2 94. Abstract.
2. Mabo P., et al. Impact of ventricular pacing on AF prevention. Pacing Clin Electrophysiol 2002;25 (Pt.II): 621. Abstract 39.
3. “99.9% intrinsic AV conduction in 28/35 (80%) of patients of non-selected DDD patients” Anselme et al. First clinical results of AAIsafeR2, a new mode to prevent ventricular pacing. Heart Rhythm 2006; 2, supp 5; p4-99 (abs).