0335 : Impact of heart-rate-lowering drugs on automatic AV delay adaptation at exercise in patients implanted with a SONRTM sensor device

We evaluated the impact of heart-rate-lowering drugs (betablokers, Ivabradine and Amiodarone) on the success of AV delay adaptation during exercise in patients implanted with a CRT-D This device is connected to the atrial SonRTipTM lead with a hemodynamic SonR sensor allowing automatic weekly AV and VV delays optimization, at rest and exercise. This prospective study evaluated patients implanted with a SonR CRT-D device in our center between November 2011 and November 2014. Only patients in sinus rhythm with a CRT optimization function programmed “on” were included. Optimization success was evaluated according to the percentage of weeks where the device succeeded AV delay optimization. Twenty-nine patients patients (67.8±9 years; 75.9% M) were included: 14 (48.2%) had an ischemic cardiomyopathy (ICM) and 15 (51.8%) a dilated cardiomyopathy (DCM). QRS duration was 165±19 msec. LVEF was 28±5%. AV delay at rest was 87±14 msec. and at exercise 54±7 msec. Beta-blockers, Amiodarone and Ivabradine were prescribed in respectively 27 (93,1%), 12(41,4%) and 4 (13,7%) patients. In 7 (24,1%) patients AV delay optimization at exercise failed due to chronotropic incompetence): 5 (35,7%) patients in the ICM group and 2 (13,3%) in the DCM group. Beta-blockers were associated to amiodarone in 4 patients, to Ivabradine in 2 patients, and beta-blockers were used alone in one patient. In both groups, the association of betablockers to Ivabradine resulted in a very poor success rate of AV delay optimization during exercise (3% in an ICM patient and 17% in a DCM patient). In patients implanted with a CRT-D device with automatic optimization of AV delay at exercise are also often treated with heart-rate-lowering drugs. Chronotropic incompetence should be anticipated by programming rate responsive algorithm in order to increase automatic AV delay optimization when a SONR™ sensor device is used. The author hereby declares no conflict of interest