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Related Concept Videos

ECG Interpretation of Arrhythmias I: Sinus Arrhythmias01:16

ECG Interpretation of Arrhythmias I: Sinus Arrhythmias

263
Arrhythmias are disturbances in the heart's rhythm that lead to abnormal heartbeats. These irregularities can originate from different parts of the heart and are classified based on their origin and nature.
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,...
263
Dysrhythmias III: Characteristics of Dysrhythmias01:29

Dysrhythmias III: Characteristics of Dysrhythmias

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Dysrhythmias, also known as arrhythmias, are irregular heart rhythms that result from abnormal electrical activity in the heart, affecting its ability to circulate blood efficiently. Tachyarrhythmias, a subset of dysrhythmias, are characterized by abnormally fast heart rates exceeding 100 beats per minute. Here are some types of tachyarrhythmias with their distinct ECG features:Sinus Tachycardia:Sinus tachycardia presents a regular heart rhythm with an increased rate of 101-180 beats per...
13
Dysrhythmias IV: Characteristics of Bradyarrhythmias01:18

Dysrhythmias IV: Characteristics of Bradyarrhythmias

12
Bradyarrhythmias are cardiac rhythm disorders characterized by a slower-than-normal heart rate, typically defined as fewer than 60 beats per minute. Some of which are discussed here:Sinus BradycardiaSinus bradycardia presents a heart rate lower than 60 beats per minute, with a regular rhythm originating from the SA node. The ECG typically shows normal P waves preceding each QRS complex, a normal PR interval (0.12 to 0.20 seconds), and a normal QRS duration (0.06 to 0.10 seconds).First-Degree AV...
12
ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias01:25

ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias

52
Arrhythmia is a condition characterized by an irregular heart rhythm, with ECG changes that differ based on its origin and nature. The types of arrhythmias discussed below include atrial, junctional, and ventricular arrhythmias.Atrial ArrhythmiasPremature Atrial Complexes (PACs): PACs are early atrial beats caused by stress, caffeine, alcohol, electrolyte imbalances, hypoxia, hyperthyroidism, or certain medications (e.g., bronchodilators and decongestants). The ECG shows early P waves with an...
52
Dysrhythmias I: Introduction01:15

Dysrhythmias I: Introduction

21
Dysrhythmias refers to abnormalities in the heart's rhythm. They result from disruptions in the heart's electrical conduction system, which includes the sinoatrial(SA)node, atrioventricular(AV) node, the bundle of His, bundle branches, and Purkinje fibers.Definition and PathophysiologyDysrhythmias result from disorders of impulse formation, impulse conduction, or both. The heart contains specialized cells in the sinoatrial node, atrioventricular node, and the bundle of His and Purkinje fibers...
21
Disturbances in Heart Rhythm01:28

Disturbances in Heart Rhythm

1.0K
Arrhythmia or dysrhythmia refers to an abnormal heart rhythm caused by a defect in the heart's conduction system. It can cause the heart to beat irregularly, too quickly, or too slowly, leading to symptoms like chest pain, shortness of breath, and fainting. Factors such as stress, caffeine, alcohol, nicotine, cocaine, certain drugs, congenital defects, diseases, and electrolyte abnormalities can trigger arrhythmias.
Arrhythmias are categorized by their speed, rhythm, and origin. A slow...
1.0K

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Microelectrode Array Recording of Sinoatrial Node Firing Rate to Identify Intrinsic Cardiac Pacemaking Defects in Mice
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Wandering Bundles With Sinus Arrhythmia.

Song Yan1, Li Wei1, Gan-Xin Yan2,3,4

  • 1Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE, Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China.

JACC. Case Reports
|June 7, 2023
PubMed
Summary

Congenital ventricular septal defect closure in a child revealed sinus arrhythmia and changing bundle branch blocks. This was due to inverse decremental conduction in the left posterior fascicle, influenced by the sinus arrhythmia

Keywords:
inverse decremental conductionleft bundle branch blockright bundle branch blockventricular septal defect

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Area of Science:

  • Pediatric Cardiology
  • Electrophysiology
  • Congenital Heart Disease

Background:

  • Ventricular septal defects (VSDs) are common congenital heart abnormalities.
  • Post-procedural cardiac rhythm disturbances require careful monitoring.
  • Sinus arrhythmia and bundle branch blocks can occur after cardiac interventions.

Purpose of the Study:

  • To investigate the electrophysiological mechanisms underlying variable bundle branch blocks after VSD closure.
  • To analyze the relationship between sinus arrhythmia and conduction abnormalities.
  • To understand inverse decremental conduction in the left posterior fascicle.

Main Methods:

  • Case study of a 3-year-old boy undergoing VSD closure.
  • Post-procedural telemetry monitoring.
  • Analysis of electrocardiogram (ECG) findings, focusing on sinus arrhythmia and bundle branch blocks.
  • Electrophysiological assessment of conduction properties.

Main Results:

  • Telemetry revealed sinus arrhythmia with intermittent right and left bundle branch blocks.
  • Inverse decremental conduction in the left posterior fascicle was identified.
  • Conduction changes correlated with the preceding RP interval during sinus arrhythmia.

Conclusions:

  • Sinus arrhythmia can precipitate variable bundle branch blocks post-VSD closure.
  • Inverse decremental conduction is a key mechanism for these electrophysiological changes.
  • Understanding these mechanisms is crucial for managing pediatric cardiac patients.