Related Experiment Video
Updated: May 7, 2026
Optocardiography and Electrophysiology Studies of Ex Vivo Langendorff-perfused Hearts
Published on: November 7, 2019
Differential sequential septal pacing: a simple maneuver to differentiate nodal versus extranodal ventriculoatrial
Nicolas Derval1, Allan C Skanes, Lorne J Gula
1Hôpital Cardiologique du Haut Lévêque, CHU Bordeaux, Pessac, France.
Background:
Distinguishing retrograde nodal conduction from extranodal conduction using an accessory pathway (AP) can sometimes be challenging.
Objective:
To distinguish nodal from extranodal ventriculoatrial (VA) conduction regardless of AP location by proposing a simple method. This method is based on the principle that moving the pacing site progressively from the basal region toward the entrance of the His-Purkinje system should shorten VA time for nodal but not for AP conduction.
Methods:
Sixty-seven patients with supraventricular tachycardia were prospectively recruited. Quadripolar catheters were placed at the right ventricular (RV) apex, right atrium, and His and coronary sinus. The RV septum was sequentially paced at 4 sites: (1) basal, (2) high midventricle, (3) low midventricle, and (4) apex at a cycle length 100 ms shorter than the resting cycle length. The stimulus-to-atrial (SA) interval was measured by using the proximal coronary sinus atrial electrogram.
Results:
Group 1 (n = 33) had nodal VA conduction; all patients had typical atrioventricular nodal reentrant tachycardia. Group 2 (n = 34) had extranodal VA conduction via an AP: 19 left-sided, 6 right-sided, and 9 posteroseptal. In group 1, the SA interval decreased significantly as pacing site moved closer toward the apex (site 1: 166 ± 35 ms, site 2: 153 ± 32 ms, site 3: 149 ± 32 ms, site 4: 154 ± 33 ms, P < .001, respectively, at sites 2-4 compared with site 1). In contrast, in group 2, the SA interval increased significantly toward the apex (site 1: 149 ± 45 ms, site 2: 158 ± 43 ms, site 3: 161 ± 43 ms, and site 4: 163 ± 40 ms, P < .001, respectively, at sites 2-4 compared with site 1). The SA interval at the high midventricular site (site 2) - SA interval at the base (site 1) ≤ 0 ms for nodal and > 0 ms for extranodal conduction had optimal sensitivity and specificity (nodal: selectivity = 97.0% and specificity = 85.3%; extranodal: selectivity = 85.3% and specificity = 97.0%).
Conclusions:
Differential sequential pacing of the RV septum reliably distinguishes retrograde atrioventricular nodal conduction from AP conduction.
More Related Videos
08:05Optimization of Transesophageal Atrial Pacing to Assess Atrial Fibrillation Susceptibility in Mice
Published on: June 29, 2022
06:57Ablation of Ischemic Ventricular Tachycardia Using a Multipolar Catheter and 3-dimensional Mapping System for High-density Electro-anatomical Reconstruction
Published on: January 31, 2019
Related Concept Videos
01:19Conduction System of the Heart
The pacemaker cells are located in two primary nodes: the sinoatrial (SA) node and the atrioventricular (AV) node. The SA node pacemaker cells can autonomously depolarize, triggering an action potential that leads to the...
01:20Conduction System of the Heart
This system relies on the unique properties of nodal and Purkinje cells:...
01:18Dysrhythmias IV: Characteristics of Bradyarrhythmias
01:19Electrophysiology of Normal Cardiac Rhythm
01:25ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias
01:16ECG Interpretation of Arrhythmias I: Sinus Arrhythmias
Types of Arrhythmias
Sinus Node Arrhythmias
Sinus Bradycardia: Originating from the sinoatrial (SA) node, sinus bradycardia involves slower impulses, resulting in a heart rate of less than 60 beats per minute (bpm). Causes include sleep, vagal stimulation, beta-blockers, hypothyroidism, and...