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Related Concept Videos

Disturbances in Heart Rhythm01:29

Disturbances in Heart Rhythm

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...
Mechanism of Cardiac Arrhythmias01:28

Mechanism of Cardiac Arrhythmias

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.
ECG Interpretation of Arrhythmias I: Sinus Arrhythmias01:16

ECG Interpretation of Arrhythmias I: Sinus Arrhythmias

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, and...
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...
Dysrhythmias II: Classification of Tachyarrhythmias01:28

Dysrhythmias II: Classification of Tachyarrhythmias

Tachyarrhythmias are a type of dysrhythmia where the heart rate exceeds 100 beats per minute. Here are some common types of tachyarrhythmias:Sinus TachycardiaSinus tachycardia originates from increased impulses from the sinus node, leading to an elevated heart rate. It is often triggered by stress, fever, or exercise.Patients may experience palpitations, a sensation of a racing heart, dizziness, and chest discomfort.Causes and Risk Factors: Common causes include physical exertion, emotional...
ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias01:25

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

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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Related Experiment Videos

High altitude arrhythmias.

D R Woods1, S Allen, T R Betts

  • 1School of Clinical Medical Sciences, University of Newcastle and Royal Army Medical Corps, Army Medical Services, Newcastle upon Tyne, UK. DoctorDRWoods@aol.com

Cardiology
|April 25, 2008
PubMed
Summary
This summary is machine-generated.

High altitude can trigger significant heart rhythm changes, including palpitations and arrhythmias, in healthy individuals. Further research is needed due to potential risks, especially for the elderly visiting high-altitude regions.

Related Experiment Videos

Area of Science:

  • Cardiology
  • Altitude Physiology
  • Sports Medicine

Background:

  • Palpitations are common complaints, but their occurrence and nature at high altitude are not well understood.
  • High altitude exposure is associated with increased cardiovascular risks, including sudden cardiac death.

Purpose of the Study:

  • To investigate the causes and characteristics of palpitations experienced at high altitude.
  • To assess cardiac electrical activity during ascent to and exposure at high altitude.

Main Methods:

  • Nine healthy male volunteers were monitored using implantable loop recorders.
  • Subjects ascended to high altitude (up to 5,000 m) with continuous cardiac monitoring during exercise, rest, and sleep.
  • Arterial oxygen saturation was measured concurrently with device activation.

Main Results:

  • All subjects reported palpitations during exercise above 5,000 m.
  • Sinus tachycardia and marked sinus arrhythmia were observed in all subjects.
  • One subject experienced atrial flutter, another had non-conducted P waves, and one showed ST segment depression.

Conclusions:

  • High altitude exposure can induce significant cardiac arrhythmias in healthy individuals.
  • The findings highlight potential cardiac risks associated with high altitude, necessitating further investigation.
  • Given the large number of annual visitors to altitude, understanding these risks is crucial, particularly for the elderly.