Open AccessNoninvasive Assessment of Atrioventricular Nodal Function: Effect of Rate‐Control Drugs during Atrial Fibrillation
Author(s) -
Corino Valentina D.A.,
Sandberg Frida,
Mainardi Luca T.,
Platonov Pyotr G.,
Sörnmo Leif
Publication year - 2015
Publication title -
annals of noninvasive electrocardiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.494
H-Index - 48
eISSN - 1542-474X
pISSN - 1082-720X
DOI - 10.1111/anec.12253
Subject(s) - esmolol , medicine , effective refractory period , refractory period , atrioventricular node , atrial fibrillation , cardiology , refractory (planetary science) , anesthesia , heart rate , tachycardia , blood pressure , physics , astrobiology
Background During atrial fibrillation (AF), conventional electrophysiological techniques for assessment of refractory period or conduction velocity of the atrioventricular (AV) node cannot be used. We aimed at evaluating changes in AV nodal properties during administration of tecadenoson and esmolol using a novel ECG‐based method. Methods Fourteen patients (age 58 ± 8 years, 10 men) with AF were randomly assigned to either 75 or 300 μg intravenous tecadenoson. After tecadenoson wash‐out, patients received esmolol continuously (100 μg/kg per min for 10 mins, then 50 μg/kg per min for 50 mins). Atrial fibrillatory rate (AFR) and heart rate (HR) were assessed in 15‐min segments. Using the novel method, we assessed the absolute refractory periods of the slow and fast pathways (aRPs and aRPf) of the AV node to produce an estimate of the functional refractory period. Results During esmolol infusion, AFR and HR were significantly decreased and the absolute refractory period was significantly prolonged in both pathways (aRPs: 387 ± 73 vs 409 ± 62 ms, P < 0.05; aRPf: 490 ± 80 vs 529 ± 58 ms, P < 0.05). During both tecadenoson doses, HR decreased significantly and AFR was unchanged. Both aRPs and aRPf were prolonged for a 75 μg dose (aRPs: 322 ± 97 vs 476 ± 75 ms, P < 0.05; aRPf: 456 ± 102 vs 512 ± 55 ms, P < 0.05) whereas a trend toward prolongation was observed for a 300 μg dose. Conclusions The estimated parameters reflect expected changes in AV nodal properties, i.e., slower conduction through the AV node for tecadenoson and prolongation of the AV node refractory period for esmolol. Thus, the proposed approach may be used to assess drug effects on the AV node in AF patients.