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The document discusses examining the PR interval as the fifth step in ECG analysis. The PR interval denotes conduction from the atria to the ventricles. Abnormal PR intervals include those that are shorter, longer, absent, or varying in duration. Causes of abnormal PR intervals include preexcitation, heart block, wandering pacemaker, and arrhythmias. Determining the type of PR interval present provides information about conduction abnormalities.
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This document discusses different types of junctional dysrhythmias:
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Image result for ecgen.wikipedia.org
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To summarize the document:
1. The document outlines the steps for systematically analyzing a 12-lead ECG: rate, rhythm, axis, intervals, hypertrophy, and evidence of infarction.
2. It describes how to calculate and interpret the PR, QRS, and QT intervals and defines normal values.
3. Criteria are provided to assess for right and left atrial enlargement, right and left ventricular hypertrophy on the ECG.
4. The document instructs the reader to look for abnormal Q waves, ST elevation or depression, and T wave changes when analyzing the ECG for evidence of a myocardial infarction.
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The PR interval represents the time taken for electrical signals to travel from the sinoatrial node through the atria and atrioventricular node to reach the ventricles. A normal PR interval is between 120-200 milliseconds. Short or long PR intervals can indicate various conduction abnormalities between the atria and ventricles. The document discusses various conditions that can cause short or long PR intervals such as first-degree heart block, Wolff-Parkinson-White syndrome, and complete heart block. It also describes what features of the PR interval such as variability, absence, or elevation/depression may indicate specific cardiac issues.
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This document discusses different types of atrioventricular (AV) heart blocks. It defines heart blocks as delays or interruptions in the conduction pathway between the atria and ventricles. It then proceeds to describe the characteristics of 1st-degree AV heart block, 2nd-degree AV heart block types I and II, and 3rd-degree AV heart block. Specifically, it notes that 2nd-degree type I shows a progressively lengthening PR interval until a QRS complex is dropped, while 2nd-degree type II shows a constant PR interval with more P waves than QRS complexes. 3rd-degree AV block results in unsynchronized atrial and ventricular rhythms from separate pacemakers. The document
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The document provides an overview of electrocardiography and the heart's electrical conduction system. It describes how an ECG works to detect and record the heart's electrical activity. It explains the anatomy of the heart including its chambers, valves, blood vessels and electrical conduction pathways. Key aspects of the cardiac cycle are outlined such as depolarization, repolarization and the roles of ions in generating electrical impulses that stimulate coordinated contractions of the heart muscle.
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Inferior lead pseudo-infarct Q waves are a common finding in the Wolff-Parkinson-White (WPW) syndrome.The characteristic Q wave-T wave vector discordance results from secondary repolarization changes due to altered ventricular activation. As a corollary, the presence of T wave inversion with inferior lead Q waves and a short PR interval is strongly suggestive, but not pathognomonic of inferior ischemia.
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This document provides an overview of an ECG rhythm interpretation course, which aims to teach students to recognize normal sinus rhythm, 13 common arrhythmias, and myocardial infarctions. The learning modules cover ECG basics, rhythm analysis, sinus rhythms, premature beats, arrhythmias, and myocardial infarction diagnosis. Specific rhythms discussed include sinus bradycardia, sinus tachycardia, premature atrial contractions, and premature ventricular contractions. The key deviations and etiologies of each rhythm are explained.
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A 17-year-old female presented with retrosternal and epigastric burning after consuming 50ml of bleach containing sodium hypochlorite. Her initial ECG showed first-degree AV block with a prolonged PR interval of 320ms that normalized to 140ms on a follow up ECG 3 days later, likely after elimination of the toxin. First-degree AV block is defined as a PR interval over 200ms and can be caused by various conditions. It typically has no symptoms but may reduce exercise tolerance and cause syncope in rare cases of infranodal block or left ventricular dysfunction. Treatment involves discontinuing any medications that may cause AV block and permanent pacing may be indicated in severe cases.
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This document provides an overview of a course on ECG rhythm interpretation and supraventricular and ventricular arrhythmias. The course objectives are to recognize normal sinus rhythm, the 13 most common rhythm disturbances, and acute myocardial infarction on ECG. The learning modules cover ECG basics, rhythm analysis, normal sinus rhythm, various arrhythmias, and myocardial infarction diagnosis. Example rhythms are provided for arrhythmias including atrial fibrillation, atrial flutter, paroxysmal supraventricular tachycardia, ventricular tachycardia, and ventricular fibrillation. Causes and characteristics of each arrhythmia are described.
Ecg
Image result for ecgen.wikipedia.org
An electrocardiogram (ECG) is a test which measures the electrical activity of your heart to show whether or not it is working normally. An ECG records the heart's rhythm and activity on a moving strip of paper or a line on a screen.
There is no difference between an ECG and an EKG. Both refer to the same procedure, however one is in English (electrocardiogram – ECG) and the other is based on the German spelling (elektrokardiogramm – EKG). ... The most common EKG is called the 12-lead EKG.
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This document provides an overview of AV junctional blocks and how to interpret ECG rhythms related to different types of AV blocks. It discusses the objectives of ECG rhythm interpretation and covers modules on ECG basics, arrhythmias, AV nodal blocks, and examples of 1st degree, 2nd degree type I and II, and 3rd degree AV blocks. For each type of block, it describes the deviation from normal sinus rhythm and potential etiologies.
BASICS IN ELECTROCARDIOGRAPHY
This document provides an overview of electrocardiography (ECG) basics. It discusses the history and key contributors to the development of ECG, including Waller, Einthoven, Goldberger, and Lewis. It describes cardiac physiology and the relationship between action potentials in myocardial cells and pacemaker cells to the ECG waveform. It also covers the basics of ECG interpretation including leads, calibration, rate, rhythm, axis, waves, segments, intervals and general approach.
How to read ecg (basic ecg findings)
This document provides an overview of how to interpret an electrocardiogram (ECG). It describes the basic components of an ECG including patient data, paper speed, calibration, lead placement, and waveform intervals. It then examines each waveform in more detail, covering the P wave, QRS complex, T wave, ST segment, and cardiac rhythm and axis. Key signs and abnormalities are outlined for each component to guide ECG interpretation.
cases of ecg interpretation
- The document describes normal ECG values and intervals. It then discusses abnormalities seen in right and left atrial and ventricular enlargement, right and left bundle branch blocks, and myocardial infarction. Specific ECG patterns are provided for each condition. For example, right atrial enlargement shows tall, narrow P waves in certain leads, while left bundle branch block results in a wide QS complex in lead V1 and tall R wave without Q wave in lead V6. The document serves as a guide for interpreting ECG findings in various cardiopulmonary conditions.
Heart block bds
This document discusses different types of heart block. Sinoatrial block occurs when the impulse from the sinus node is blocked before entering the atrial muscle, causing the atria to stop beating. Atrioventricular block occurs when impulses are blocked from passing from the atria to the ventricles. There are three degrees of atrioventricular block: first degree is a prolonged P-R interval; second degree is intermittent blocking of impulses; third degree is a complete dissociation between the atria and ventricles. Causes of atrioventricular block include ischemia, compression, inflammation, or stimulation of the vagus nerves.
Cardiac axis
The document discusses the cardiac axis and methods for determining it from an electrocardiogram (ECG). The cardiac axis represents the overall direction of electrical conduction through the heart. It is normally between -30° and +90° but can deviate left or right. Left axis deviation occurs between -30° and -90° and may indicate conduction abnormalities, while right axis deviation is between +90° and +180° and can be caused by right ventricular hypertrophy. The hexaxial reference system and other methods are described for calculating the axis from the ECG readings.
Junctional arrhythmias
This document discusses junctional rhythms, which occur when the atrioventricular (AV) node acts as the backup pacemaker when the sinoatrial (SA) node fails. There are three types of junctional rhythm: junctional rhythm with a rate of 40-60 bpm; accelerated junctional rhythm with a rate of 61-100 bpm; and junctional tachycardia with a rate of 101-180 bpm. All junctional rhythms lack P waves or have inverted, buried, or retrograde P waves and a absent, short, or retrograde PR interval. Causes include SA node disease, increased vagal tone, digitalis use, and inferior wall myocardial infarction. Treatment options are
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This document provides information on interpreting electrocardiograms (ECGs) to diagnose acute myocardial infarction (AMI). It discusses that an AMI is diagnosed using a 12-lead ECG rather than just a rhythm strip. The 12-lead ECG views the heart from 12 angles and can identify elevation in specific leads to determine if the AMI is located in the anterior, lateral, or inferior wall of the heart. Anterior wall AMIs present with ST elevation in leads V1-V4, lateral wall AMIs in leads I, aVL, and V5-V6, and inferior wall AMIs in leads II, III, and aVF. The document uses examples of 12-lead ECGs to demonstrate identifying
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This document discusses various arrhythmias of the atria including atrial ectopic beats, atrial tachycardia, atrial flutter, and atrial fibrillation. It provides details on the characteristic electrocardiogram patterns of each condition, including descriptions of the P waves, QRS rate and rhythm, and QRS width. Atrial ectopic beats involve premature impulses from the atria. Atrial tachycardia has a regular rapid heart rate between 150-200 bpm. Atrial flutter sees sawtooth flutter waves in the baseline at a rate of 300 bpm. Atrial fibrillation is characterized by irregular rapid impulses that prevent effective atrial emptying.
Rapid Review of basic ECG
This document provides a brief review of EKG arrhythmias arranged by Hosam Ghanem from Damascus University. It includes definitions and descriptions of normal sinus rhythm, sinus bradycardia, sinus tachycardia, wandering pacemaker, atrial flutter, atrial fibrillation, junctional rhythm, premature ventricular contraction, ventricular tachycardia, ventricular fibrillation, pacer rhythm, first-degree atrioventricular block, second-degree atrioventricular block, third-degree atrioventricular block, right bundle-branch block, left bundle-branch block, left atrial hypertrophy, right atrial hypertrophy, right ventricular hypertrophy, and left ventricular hypert
ECG PART 10 final
To summarize the document:
1. The document outlines the steps for systematically analyzing a 12-lead ECG: rate, rhythm, axis, intervals, hypertrophy, and evidence of infarction.
2. It describes how to calculate and interpret the PR, QRS, and QT intervals and defines normal values.
3. Criteria are provided to assess for right and left atrial enlargement, right and left ventricular hypertrophy on the ECG.
4. The document instructs the reader to look for abnormal Q waves, ST elevation or depression, and T wave changes when analyzing the ECG for evidence of a myocardial infarction.
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The PR interval represents the time taken for electrical signals to travel from the sinoatrial node through the atria and atrioventricular node to reach the ventricles. A normal PR interval is between 120-200 milliseconds. Short or long PR intervals can indicate various conduction abnormalities between the atria and ventricles. The document discusses various conditions that can cause short or long PR intervals such as first-degree heart block, Wolff-Parkinson-White syndrome, and complete heart block. It also describes what features of the PR interval such as variability, absence, or elevation/depression may indicate specific cardiac issues.
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This document provides an overview of electrocardiography (ECG) and ECG interpretation. It discusses the conduction system of the heart and how ECG works to record and display the heart's electrical activity. A systematic 8-step approach to ECG interpretation is outlined, examining rate, rhythm, intervals, waves, segments, and arriving at an overall interpretation. Common ECG patterns for myocardial ischemia, injury, and infarction are reviewed.
Ecg interpretation
The document provides an overview of electrocardiogram (ECG) interpretation. It discusses the key steps including assessing quality, rate, rhythm, axis, P wave, PR interval, QRS duration and morphology, ST segment, T wave, QT interval, and identifying common abnormalities. Examples of important ECG patterns are also shown, such as lateral myocardial infarction, left bundle branch block, ventricular tachycardia, and Wolff-Parkinson-White syndrome. The overall document aims to develop a structured approach for interpreting ECGs in clinical practice.
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This document provides an outline for electrocardiogram (ECG or EKG) interpretation. It begins with an introduction to ECGs and their purpose. It then discusses ECG physiology, the different types of ECG tests, indications for ECGs, how to record an ECG, and an 8-step approach to ECG interpretation. Finally, it covers common ECG abnormalities and their significance. The overall document serves as a comprehensive guide for understanding ECGs, from the basics of what they measure to interpreting tracings and recognizing abnormal findings.
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1. The document discusses rhythm identification and interpretation of electrocardiograms (EKGs). It covers the basics of rate, rhythm, axis, hypertrophy, and infarction.
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This document discusses different types of conduction blocks that can occur in an ECG. It describes first-degree AV block, characterized by a prolonged PR interval but normal conduction ratio of 1:1. Second-degree AV block is divided into Mobitz type I (Wenckebach) where the PR interval lengthens until a P wave fails to conduct, and Mobitz type II where there is a fixed PR but dropped beats. Third-degree AV block is complete heart block where the atria and ventricles contract independently. ST segment changes can indicate myocardial ischemia or infarction, with elevation associated with transmural MI and depression with non-transmural MI.
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Atrial dysrhythmias originate outside the SA node and are caused by three mechanisms. Key characteristics include abnormal P waves and P-R intervals with normal QRS complexes. Wandering atrial pacemaker causes shifting P wave morphology. Premature atrial complexes produce irregularity with differently shaped P waves preceding QRS. Atrial tachycardia arises from the atria at 150-250 bpm, overriding the SA node. Atrial flutter has a saw-tooth appearance at 250-350 bpm. Atrial fibrillation is chaotic firing with fibrillatory waves but no P waves.
5th part ECG basics: supraventricular arrhythmias Dr Salah Mabrouk Khallaf
Heart rate regular regular iiregularity iiregular iregularity tachycadia bradycardia sinus atrial junctionla ectopics rythm arrest supraventricular arrythmia
Svt evaluation
Supraventricular tachycardias are a common clinical problem that originate above the His bundle. The main types discussed are AV nodal reentrant tachycardia, AV reentrant tachycardia mediated by accessory pathways, and atrial tachycardia. AVNRT involves a reentrant circuit within the AV node while AVRT uses an accessory pathway between the atria and ventricles. Atrial tachycardia originates from a focal point in the atria. The document provides details on mechanisms, presentations, diagnoses and treatment of these arrhythmias.
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2. Specific techniques are outlined for using differential pacing and para-Hisian pacing to confirm the presence of a retrogradely conducting accessory pathway.
3. Factors that may influence the EP study are also discussed, such as using drugs to induce arrhythmias, ensuring the appropriate tissue is being captured, and considering special circumstances like myotonic dystrophy.
BLUE Basics Of ECG.pdf
This document provides an overview of basics of electrocardiography (ECG) including anatomy and physiology of the heart, conduction system of the heart, blood flow through the heart, electrophysiology of the heart, components of the ECG complex, how to analyze rhythms like normal sinus rhythm and various arrhythmias, diagnosing myocardial infarction using 12-lead ECGs, and distinguishing between ST-elevation and non-ST-elevation myocardial infarctions. The document contains detailed information on interpreting ECGs and using 12-lead ECGs to locate the site of myocardial infarction.
Ekg module 4c
This document provides an overview of AV junctional blocks, including first, second, and third degree blocks. It defines each type of block, describes how they deviate from normal sinus rhythm, and provides their etiologies. Rhythms illustrating each type of block are presented along with their interpretations. It is intended to teach the reader how to recognize and understand different types of AV junctional blocks.
ECG OF THE WEEK.pptx
This ECG shows a case of typical atrioventricular nodal reentrant tachycardia (AVNRT) in a 51-year-old male presenting with palpitations, giddiness, and sweating. The ECG shows a narrow complex tachycardia at a rate of 180 bpm with retrograde P waves and a short RP interval consistent with AVNRT using the slow-fast conduction pathway. AVNRT is the most common type of supraventricular tachycardia involving reentry between the slow and fast pathways within the AV node. Treatment options include vagal maneuvers, medications like adenosine, verapamil, or diltiazem, and radiofrequency
Ecg
This document provides an overview of electrocardiography (ECG) basics. It defines ECG as a graphical representation of the heart's electrical activity used to assess cardiovascular diseases. It discusses the conduction system of the heart and the 12 standard chest leads used in ECG. It outlines the key steps in ECG interpretation including analyzing rate, rhythm, intervals, chambers, and waveform durations. It describes how to calculate heart rate from the ECG and defines the normal P wave, PR interval, QRS complex, ST segment, QT interval, and ECG axis.
cardiac arrhythmias
This document provides information on cardiac conduction systems, normal ECG rhythms, cardiac arrhythmias, and arrhythmia management. It defines normal sinus rhythm on ECG and describes the two main types of arrhythmias as bradycardia and tachycardia. Nine common arrhythmias are defined including atrial flutter, atrial fibrillation, junctional rhythm, and various ventricular arrhythmias. Treatment options for arrhythmias include electrical cardioversion, antiarrhythmic medications, and pacemakers.
Ecg interpretation , Upgraded
ECG Interpretation
The ECG is used to diagnose heart conditions by representing the electrical activity of the heart over time. It can detect abnormalities in heart rhythm, rate, and structure. A standard ECG has 12 leads that examine the heart from different angles. Common things to analyze include rhythm, rate, axis, waves, intervals, and complexes. Various arrhythmias and conduction abnormalities can be identified based on their characteristic ECG patterns.
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- 1. Q I A 7 Fast & Easy ECGs – A Self-Paced Learning Program PR Intervals
- 2. Step 5 of ECG Analysis • Examining the PR intervals Q
- 3. The PR Interval • Denotes depolarization of the heart from the SA node through the atria, AV node and His-Purkinje system
- 4. The PR Interval • The distance from the beginning of the P wave to the beginning of the Q wave • Morphology is a P wave and a flat line I
- 5. The PR Interval • Considered abnormal if they are shorter, longer, absent or vary
- 6. Shorter P’R Intervals • Shorter P’R intervals occur when the impulse originates in the atria close to the AV junction or in the AV junction
- 8. Shorter P’R Intervals • Can occur when an impulse arises from a supraventricular site but travels through abnormal accessory pathways to the ventricles • Leads to premature ventricular depolarization called preexcitation
- 10. Longer P’R Intervals • Occur when there is a delay in impulse conduction through the AV node • For example, 1st-degree AV heart block
- 11. Varying P’R Intervals • In wandering atrial pacemaker the pacemaker site moves from beat to beat causing the P’ waves to appear different and the P’R intervals to vary
- 12. Varying P’R Intervals • 2nd-degree AV heart block, Type I has PR intervals that are progressively longer until a QRS complex is dropped and then the cycle repeats
- 13. Absent PR Intervals • Occurs in atrial flutter and fibrillation and ventricular dysrhythmias
- 14. Absent PR Intervals • In 3rd-degree AV heart block the PR interval is not measurable
- 15. More P Waves and Constant PR Intervals • In 2nd-degree AV heart block, Type II, some sinus beats are blocked in the AV node and do not reach the ventricles • PR intervals associated with P waves that are conducted through to the ventricles are constant
- 16. More P Waves and Constant PR Intervals I
- 17. Practice Makes Perfect • Determine the type of PR interval I
- 18. Practice Makes Perfect • Determine the type of PR interval I
- 19. Practice Makes Perfect • Determine the type of PR interval I
- 20. Practice Makes Perfect • Determine the type of PR interval I
- 21. Practice Makes Perfect • Determine the type of PR interval I
- 22. Summary • Fifth step of analyzing an ECG rhythm is examining the PR intervals. • PR interval is the distance from the beginning of the P wave to the beginning of the Q wave. • Duration of the PR interval is normally 0.12 to 0.20 seconds. • PR intervals are considered abnormal if they are shorter, longer, absent or vary.
- 23. Summary • Shorter P’R intervals occur when the impulse originates in the atria close to the AV junction or in the AV junction itself. • 1st-degree AV heart block is the most common cause of longer PR intervals. • In wandering atrial pacemaker the pacemaker site moves from beat to beat causing the P’ waves to appear different and the P’R intervals to vary.
- 24. Summary • In 2nd-degree AV heart block, Type I, PR intervals are progressively longer until a QRS complex is dropped and then the cycle repeats. • There is an absence of PR intervals in atrial flutter and fibrillation, ventricular dysrhythmias. • In 3rd-degree AV heart block the PR intervals are not measurable.
- 25. Summary • In 2nd-degree AV heart block, Type II, some of the sinus beats are blocked in the AV node and do not reach the ventricles. The PR intervals associated with the P waves that are conducted through to the ventricles are constant.