Tachy-brady arrhythmias: the critical role of adenosine-induced sinoatrial conduction block in post-tachycardia pauses.

ABSTRACT:

Background

In patients with sinoatrial nodal (SAN) dysfunction, atrial pauses lasting several seconds may follow rapid atrial pacing or paroxysmal tachycardia (tachy-brady arrhythmias). Clinical studies suggest that adenosine may play an important role in SAN dysfunction, but the mechanism remains unclear.

Objective

To define the mechanism of SAN dysfunction induced by the combination of adenosine and tachycardia.

Methods

We studied the mechanism of SAN dysfunction produced by a combination of adenosine and rapid atrial pacing in isolated coronary-perfused canine atrial preparations by using high-resolution optical mapping (n = 9). Sinus cycle length and sinoatrial conduction time (SACT) were measured during adenosine (1-100 μM) and DPCPX (1 μM; A1 receptor antagonist

SUBMITTER: Lou Q 

PROVIDER: S-EPMC3858187 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature