Post on 14-Jan-2016
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Electrocardiogram
Vectorial Analysis of the Normal Electrocardiogram
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Electrocardiogram
Vectorcardiogram
Electrocardiogram
Vectorial Analysis of the Normal Electrocardiogram
This sequence of repolarization is postulated to be caused by the high blood pressure inside the ventricles during contraction, which greatly reduces coronary blood flow to the endocardium, thereby slowing repolarization in the endocardial areas.
Electrocardiogram
Vectorial Analysis of the Normal Electrocardiogram
Electrocardiogram
Mean Electrical Axis of the Ventricular QRS
Electrocardiogram
At the end of deep expiration
When a person lies down
In stocky, fat people
At the end of deep inspiration
When a person stands up
In tall, lanky people
To the rightTo the left
Normal Ventricular Conditions That Cause Axis Deviation
Electrocardiogram
To the rightTo the left
Abnormal Ventricular Conditions That Cause Axis Deviation
Hypertrophic left ventricle Hypertrophic left ventricle
Also they cause a prolonged QRS complex
Electrocardiogram
To the rightTo the left
Abnormal Ventricular Conditions That Cause Axis Deviation
Left Bundle Branch Block
Right Bundle Branch Block
Also they cause a prolonged QRS complex
Electrocardiogram
Hypertrophy of the muscle
Old infarctionConditions
Surrounding the Heart:◦ Fluid in the
pericardium◦ Pleural effusion◦ Pulmonary
emphysema
Decreased Voltage
Increased Voltage
Conditions That Cause Abnormal Voltages of the QRS Complex
Arrhythmia
A) Normal tracing
B) Very early pattern (hours after infarction)
C) Later pattern (many hours to a few
days)
D) Late established pattern (many days to weeks)
E) Very late pattern( many months to years) after the infarction
Arrhythmia
Arrhythmia Abnormal Sinus Rhythms
1. Tachycardia (> 100):◦Increased body temperature
(up to 41 oC, 1 oC → 18 beat/min)
◦Stimulation of the heart by the sympathetic nerves
(heart failure and shock)◦Toxic conditions of the heart
2. Bradycardia (<60):◦In athletes (physiologic)oVagal Stimulation (carotid sinus
Syndrome)
Arrhythmia Abnormal Sinus Rhythms
Deep respiration
Quiet respiration
Sinus Arrhythmia
Block of Heart Signals Within the Intracardiac Conduction Pathways
Sinoatrial Block
ArrhythmiaBlock of Heart Signals Within the Intracardiac Conduction
PathwaysAtrioventricular Block
1 .First Degree Block
2 .Second Degree Block
3 .Third Degree Block
Stokes-Adams Syndrome-Ventricular Escape
ArrhythmiaPremature Ventricular Contractions (PVC)
•Prolonged QRS
• High voltage QRS
•T wave has opposite
direction than QRS
Natural Excitation of the Heart
Purkinje fibers and Reentry Mechanisms
Wolff-Parkinson-White syndrome.
Normal PR
WWS
Short PR
Arrhythmia
Hypokalemia is a serious condition, but it is not as rapidly fatal as hyperkalemia
Hypercalcemia leads heart to stops in systole (calcium rigor). Hypocalcemia leads causes prolongation of the ST segment and consequently of the QT interval