Background: Decrease of non-responder rate is the main challenge in cardiac resynchronization therapy (CRT). The problem could partly be solved by consequent individualization of hemodynamic pacing parameters. Adverse timing can be assumed in patients with AV delays shorter than individual implant-related individual interatrial conduction intervals (IACT).
Objectives: To detect and to prevent hemodynamic adverse timing in CRT patients using esophageal left atrial electrogram.
Methods: By perorally applying a TOslim electrode in 20 patients (5 f, 15 m, aged 69±10 yrs) carrying CRT with AV delay (AVD) in factory settings, esophageal left atrial electrogram (LAE) of the Biotronik ICS 3000 programmer was utilized to quantify IACTs in VDD and DDD operation and to individualize the AVDs by AVD = IACT + 50ms.
Results: We measured IACTs of 30±26 ms in VDD and 97±33 ms in DDD pacing, at mean. In 3 of the 20 patients (15%) we observed hemodynamic adverse timing. In this patients, the IACTs exceeded the factory AVDs by 23±5 ms, at mean.
Conclusions: Esophageal left atrial electrogram is a useful method to exclude hemodynamic adverse timing in CRT patients.