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Dysrhythmias IV: Characteristics of Bradyarrhythmias01:18

Dysrhythmias IV: Characteristics of Bradyarrhythmias

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...
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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.
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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...
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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...
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Optimal pace timing for left bundle branch area pacing with or without an additional LV lead: results from the CSPOT study.

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Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
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[Concealed His bundle extrasystoles causing atrioventricular block].

Marek Jastrzębski1, Tomasz Sondej, Piotr Kukla

  • 1I Klinika Kardiologii i Elektrokardiologii Interwencyjnej oraz Nadciśnienia Tętniczego, Szpital Uniwersytecki, Kraków. mcjastrz@cyf-kr.edu.pl

Kardiologia Polska
|June 22, 2013
PubMed
Summary

This study details a 37-year-old male experiencing frequent extrasystoles and atrioventricular block. Electrophysiological testing revealed His bundle ectopy as the cause of his arrhythmias.

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Area of Science:

  • Cardiology
  • Electrophysiology
  • Cardiac Electrophysiology

Background:

  • Atrioventricular (AV) block and extrasystoles can significantly impact cardiac function.
  • His bundle ectopy is a recognized, though less common, cause of cardiac arrhythmias.

Observation:

  • A 37-year-old male presented with frequent premature beats (extrasystoles) and second-degree atrioventricular block.
  • Electrocardiogram (ECG) findings were consistent with underlying electrical conduction abnormalities.

Findings:

  • Electrophysiological study (EPS) confirmed manifest and concealed His bundle ectopy.
  • This ectopy was identified as the direct cause of both the bradyarrhythmia (slow heart rate) and tachyarrhythmia (fast heart rate) observed.

Implications:

  • Accurate diagnosis of His bundle ectopy is crucial for managing complex arrhythmias.
  • Understanding the electrophysiological basis of these arrhythmias can guide targeted therapeutic strategies.