Related Experiment Video
Updated: Dec 9, 2025
09:20
Microelectrode Array Recording of Sinoatrial Node Firing Rate to Identify Intrinsic Cardiac Pacemaking Defects in Mice
Published on: July 5, 2021
3.4K
Significance of Ventricular Arrhythmia Based on Stored Electrogram Analysis in a Pacemaker Population
Junya Hosoda1, Toshiyuki Ishikawa1, Katsumi Matsumoto1
1Department of Medical Science and Cardio-renal Medicine, Yokohama City University Graduate School of Medicine.
International Heart Journal
|September 14, 2020
Summary
Right ventricular pacing over 50% is a risk factor for non-sustained ventricular tachycardia (NSVT) in pacemaker patients. However, NSVT did not increase mortality due to preserved heart function.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Devices
Background:
- Ventricular arrhythmias in pacemaker patients are not well understood.
- Pacemakers store electrograms (EGMs) that can be analyzed for arrhythmias.
Purpose of the Study:
- To determine the occurrence rate of non-sustained ventricular tachycardia (NSVT) in pacemaker patients.
- To identify risk factors for NSVT in this population.
- To assess the association between NSVT and mortality.
Main Methods:
- Analysis of 1024 EGMs from 302 dual-chamber pacemaker patients.
- Definition of NSVT: ≥ 5 consecutive ventricular beats at ≥ 150 bpm for < 30 seconds.
- Multivariate analysis to identify independent risk factors.
Main Results:
- NSVT was identified in 41.0% of analyzed EGMs.
- During a mean follow-up of 46.1 months, 33.1% of patients experienced NSVT.
- ≥ 50% right ventricular pacing was an independent risk factor for NSVT (OR, 4.519; P < 0.001).
- NSVT was not associated with increased all-cause mortality.
Conclusions:
- High rates of right ventricular pacing are a significant risk factor for NSVT in pacemaker recipients.
- Despite NSVT occurrence, preserved left ventricular function mitigates the risk of increased mortality.
Related Concept Videos
01:25ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias
309
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...
309
01:19Electrophysiology of Normal Cardiac Rhythm
8.4K
The normal cardiac rhythm is a synchronized electrical activity that facilitates the regular and coordinated contraction of the heart muscle. This process is essential for efficient blood circulation throughout the body. The fundamental elements involved in establishing and maintaining this rhythm include the unique electrical properties of cardiac muscle cells, the sinoatrial (SA) node's pacemaker function, the specialized conducting system, and the ionic mechanisms underlying each phase...
8.4K
01:29Electrocardiogram
4.9K
An electrocardiogram (ECG or EKG) is a critical diagnostic tool that records the electrical signals produced by the heart during each heartbeat. This recording is achieved through electrodes placed strategically on the arms, legs, and chest. The electrocardiograph amplifies these signals and produces 12 distinct tracings, offering a comprehensive understanding of the heart's electrical activity.
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and...
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and...
4.9K
01:28Mechanism of Cardiac Arrhythmias
1.5K
Arrhythmias are irregular heart rhythms occurring when the heart's electrical impulses become abnormal. These disturbances can lead to various symptoms, depending on their severity and the underlying cause. Some common factors contributing to arrhythmias include hypoxia, ischemia, electrolyte imbalances, excessive catecholamine exposure, drug toxicity, and muscle overstretching. Arrhythmias can be classified into two main types based on the rate and site of origin of abnormal heart rhythms.
1.5K
01:16ECG Interpretation of Arrhythmias I: Sinus Arrhythmias
607
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,...
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,...
607
01:29Disturbances in Heart Rhythm
2.2K
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 heart...
Arrhythmias are categorized by their speed, rhythm, and origin. A slow heart...
2.2K