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Related Concept Videos

Electrocardiogram01:29

Electrocardiogram

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 the T...
Electrocardiogram Fundamentals01:28

Electrocardiogram Fundamentals

Introduction
An electrocardiogram (ECG) is a diagnostic tool for identifying cardiac conditions such as arrhythmias, conduction abnormalities, and myocardial ischemia.
Definition
An electrocardiogram (ECG) visualizes the heart's electrical activity by tracing the electrical movement associated with each heartbeat on a graph or monitor. As the heart beats, an electrical wave passes through it, correlating with the cardiac cycle events.
Parts of an ECG
An ECG utilizes electrodes on the skin to...
Cardiac Action Potential01:30

Cardiac Action Potential

Cardiac action potentials are essential for proper heart function, enabling the rhythmic contractions needed for adequate blood circulation. Nodal cells and Purkinje fibers, specialized for electrical conduction, generate these action potentials.
The cardiac action potential process involves a series of phases characterized by the movement of ions across the cardiac cell membranes, leading to the depolarization and repolarization of the cardiac myocytes.
Ionic Basis of Cardiac Action Potentials
Dysrhythmias V: Evaluating Dysrhythmias01:30

Dysrhythmias V: Evaluating Dysrhythmias

Dysrhythmias, also known as arrhythmias, are disturbances in the heart's rhythm that range from benign to life-threatening. A thorough evaluation is crucial for appropriate management and involves a comprehensive medical history, physical examination, and various diagnostic tests.Medical HistorySymptoms: Collect detailed information on palpitations, dizziness, syncope, chest pain, and fatigue. Note their onset, frequency, and triggers.Previous Cardiac Issues: Document any history of heart...
Correlation between ECG and Cardiac Cycle01:25

Correlation between ECG and Cardiac Cycle

The electrical signals recorded on an electrocardiogram (ECG) occur before the mechanical processes of contraction and relaxation during the cardiac cycle.
A cardiac action potential originates in the SA node and spreads throughout the atria and the AV node in approximately 0.03 seconds. This results in the P wave in an ECG and triggers atrial contraction. The action potential is then briefly slowed at the AV node, allowing the atria to contract and fill the ventricles with blood before...
Pulse rhythm01:30

Pulse rhythm

Pulse rhythm refers to the pattern of pulsations within specific intervals, offering valuable insights into the regularity or irregularity of the heart's beats as observed through the pattern of pulsation within specific intervals. A regular pulse exhibits a consistent heart rate with uniform waveforms and pulsation force, variations of which can be classified as normal, weak, or bounding.
Conversely, an irregular pulse pattern is termed dysrhythmia, stemming from disruptions in cardiac muscle...

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Related Experiment Video

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A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis
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A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis

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The electrocardiogram in the patient with syncope.

Jacqueline Dovgalyuk1, Christopher Holstege, Amal Mattu

  • 1Department of Emergency Medicine, University of Virginia, Charlottesville, VA, USA.

The American Journal of Emergency Medicine
|July 4, 2007
PubMed
Summary

The electrocardiogram (ECG) is crucial for diagnosing syncope, helping identify causes of fainting and guiding emergency treatment. Specific ECG findings can reveal serious heart conditions, aiding prompt patient management.

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Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus
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Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus

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Patient Directed Recording of a Bipolar Three-Lead Electrocardiogram using a Smartwatch with ECG Function
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Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus
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Patient Directed Recording of a Bipolar Three-Lead Electrocardiogram using a Smartwatch with ECG Function

Published on: December 11, 2019

Area of Science:

  • Cardiology
  • Emergency Medicine
  • Clinical Diagnostics

Background:

  • Syncope is a frequent and complex emergency department presentation.
  • Clinical risk scores and decision rules aid in identifying high-risk syncope patients.
  • Electrocardiogram (ECG) is a key variable in syncope evaluation.

Purpose of the Study:

  • To review the utility of the 12-lead ECG in evaluating patients presenting with syncope.
  • To discuss specific electrocardiographic findings associated with syncope.
  • To highlight how ECG findings guide diagnosis, therapy, and disposition.

Main Methods:

  • Review of existing literature and clinical guidelines on ECG interpretation in syncope.
  • Analysis of specific ECG abnormalities and their correlation with causes of syncope.
  • Discussion of the role of ECG in risk stratification for adverse events.

Main Results:

  • Specific ECG findings like bradycardia, heart block, and tachydysrhythmias can explain syncope.
  • Morphologic ECG abnormalities suggest underlying cardiovascular diseases (e.g., ACS, Wolff-Parkinson-White, Brugada, Long QT, HCM).
  • ECG interpretation is vital for identifying serious cardiac conditions and guiding management.

Conclusions:

  • The 12-lead ECG is indispensable in the emergency evaluation of syncope.
  • Distinct ECG patterns provide etiological insights and direct immediate therapeutic decisions.
  • ECG analysis is fundamental for risk assessment and determining patient disposition in syncope cases.