Related Experiment Video
Updated: Dec 17, 2025

Cox-Maze IV Procedure Concomitant with Valvular Surgery In Situs Inversus Dextrocardia: A Single-Center Experience in China
Published on: February 11, 2022
A rare case of narrow QRS tachycardia with "hidden" concealed left-sided accessory pathway
D Prochnau1, N Boski2, I Valchanov2
1Department of Internal Medicine I, Sophien- and Hufeland-Hospital Weimar, Henry-van-de-Velde-Straße 2, 99425, Weimar, Germany. d.prochnau@klinikum-weimar.de.
Abstract:
A 54-year-old-woman with narrow QRS tachycardia (heart rate, 210 beats per minute) was admitted to the authors' hospital. Tachycardia terminated after administration of adenosine. The 12-lead electrocardiogram after conversion to sinus rhythm was unremarkable. During electrophysiological study, tachycardia could be easily induced by programmed atrial stimulation without jump phenomenon. The cycle length was 260 ms. During tachycardia, the atrial activation sequence in the coronary sinus (CS) was distal-to-proximal. However, during decremental ventricular pacing, retrograde conduction showed exclusively proximal-to-distal activation in the CS. What is the underlying mechanism?
More Related Videos
10:17Real-Time Cardiac Mapping with a Noninvasive Imageless Electrocardiographic Imaging System
Published on: April 11, 2025
12:45Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
Related Concept Videos
Dysrhythmias IV: Characteristics of Bradyarrhythmias
Dysrhythmias III: Characteristics of Dysrhythmias
ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias
Dysrhythmias II: Classification of Tachyarrhythmias
ECG 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,...
Mechanism of Cardiac Arrhythmias