Paper English 3 EKG & Echo

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ELECTROCARDIOGRAPHY AND ECHOCARDIOGRAPHY Fadillah Nur Herbuono 030.06.085 Medical Faculty of Trisakti University Jakarta

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ELECTROCARDIOGRAPHY AND ECHOCARDIOGRAPHYFadillah Nur Herbuono 030.06.085Medical Faculty of Trisakti University Jakarta 2010PREFACEThis paper, titled “Electrocardiography And Echocardiography”, I arranged in order to complete my English assignment for subject medical English 3 in the faculty of medicine, trisakti university. I arrange this paper so simple in order to make these topics easier. I hope this paper’s topics is compatible and can give the information which needed by friends or

Transcript of Paper English 3 EKG & Echo

Page 1: Paper English 3 EKG & Echo

ELECTROCARDIOGRAPHY AND ECHOCARDIOGRAPHY

Fadillah Nur Herbuono

030.06.085

Medical Faculty of Trisakti University

Jakarta

2010

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PREFACE

This paper, titled “Electrocardiography And Echocardiography”, I arranged in order

to complete my English assignment for subject medical English 3 in the faculty of medicine,

trisakti university.

I arrange this paper so simple in order to make these topics easier. I hope this paper’s

topics is compatible and can give the information which needed by friends or everybody as

medical student and physicians both here and abroad.

I realized that this paper is too far from perfect, but I have tried to arrange this paper to be

good enough for us as medical student. I hope all the readers who had read this paper will

continue to find all of things about these topics. So their knowledge didn’t come only from

this paper, but all the information from the other sources.

With this time, I would like to say thank you to my teacher, DR. Dr. H. Ardiyan Boer, Sm.

Hk. who taught and helped, my friends, and everybody who helped and inspiring me during

the process of making this paper so I can finished this paper. Finally I hope this paper can be

useable for us.

Thank you

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ABSTRACT

Electrocardiography and Echocardiography are diagnostic tool that very useful for

determining whether a person has heart disease. The electrocardiogram (ECG or EKG) is a

diagnostic tool that measures and records the electrical activity of the heart in exquisite detail,

gives a graphic recording of the electric forces generated by the heart during depolarization

and repolarization. Interpretation of these details allows diagnosis of a wide range of heart

conditions. These conditions can vary from minor to life threatening. And Echocardiography

is a unique non-invasive method for imaging the living heart, to create a moving picture of

the heart, to make images of the heart chambers, valves and surrounding structures. It is

based on detection of echoes produced by a beam of ultrasound (very high frequency sound)

pulses transmitted into the heart.

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INTRODUCTION

The electrocardiogram (ECG or EKG) is a diagnostic tool that measures and records the

electrical activity of the heart in exquisite detail. Interpretation of these details allows

diagnosis of a wide range of heart conditions. These conditions can vary from minor to life

threatening.

The term electrocardiogram was introduced by Willem Einthoven in 1893 at a meeting of the

Dutch Medical Society. In 1924, Einthoven received the Nobel Prize for his life's work in

developing the ECG.

The ECG has evolved over the years.

The standard 12-lead ECG that is used throughout the world was introduced in 1942.

It is called a 12-lead ECG because it examines the electrical activity of the heart from

12 points of view.

This is necessary because no single point (or even 2 or 3 points of view) provides a

complete picture of what is going on.

To fully understand how an ECG reveals useful information about the condition of

your heart requires a basic understanding of the anatomy (that is, the structure) and

physiology (that is, the function) of the heart.

And Echocardiography is a unique non-invasive method for imaging the living heart. It is

based on detection of echoes produced by a beam of ultrasound (very high frequency sound)

pulses transmitted into the heart.

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From its introduction in 1954 to the mid 1970's, most echocardiographic studies employed a

technique called M-mode, in which the ultrasound beam is aimed manually at selected

cardiac structures to give a graphic recording of their positions and movements. M-mode

recordings permit measurement of cardiac dimensions and detailed analysis of complex

motion patterns depending on transducer angulation. They also facilitate analysis of time

relationships with other physiological variables such as ECG, heart sounds, and pulse

tracings, which can be recorded simultaneously.

A more recent development uses electromechanical or electronic techniques to scan the

ultrasound beam rapidly across the heart to produce two-dimensional tomographic images of

selected cardiac sections. This gives more information than M-mode about the shape of the

heart and also shows the spatial relationships of its structures during the cardiac cycle.

A comprehensive echocardiographic examination, utilizing both M-mode and two

dimensional recordings, therefore provides a great deal of information about cardiac anatomy

and physiology, the clinical value of which has established echocardiography as a major

diagnostic tool.

This unit covers the principles of two-dimensional echocardiography in more detail; it

explains the normal two-dimensional recordings in terms of the anatomy of the cardiac

sections scanned by the ultrasound beam. Some supplementary M-mode recordings are

included. Subsequent units will discuss applications of both M-mode and two-dimensional

echocardiography in acquired and congenital disease.

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References Review

I. ELECTROCARDIOGRAPHY (ECG)

Definition(1)

A galvanometer and electrodes with six limb leads and six chest leads. Gives a graphic

recording of the electric forces generated by the heart during depolarization and

repolarization. The electrocardiogram is recorded on graph paper with divisions.

Terminology(1)

- Depolarization:

Electrical activation of the myocardium.

- Repolarization:

Restoration of the electrical potential of the myocardial cell.

- P wave:

ECG deflection representing atrial depolarization. Atrial repolarization occurs during

ventricular depolarization and is obscured.

- QRS wave:

ECG deflection representing ventricular depolarization.

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- T wave:

ECG defection representing ventricular repolarization.

- Normal R Wave Progression:

Vl Consists of a small R wave and a large S wave, whereas V6 consists of a small Q wave

and a large R wave. Since V3 and V4 are located midway between Vl and V6, the QRS

complex would be expected to be nearly isoelectric in one of these leads; i.e., the positive and

negative deflections will be about equal.

Sequence

Depolarization occurs in the sinoatrial (SA) node. Current travels through internodal tracts of

the atria to the atrioventricular (AV) node. Then through Bundle of His, which divides into

right and left bundle branches. Left bundle branch divides into left anterior and posterior

fascicles.

ECG Electrodes(1)

Two arrangements, bipolar and unipolar leads.

1. Bipolar Lead:

One in which the electrical activity at one electrode is compared with that of another. By

convention, a positive electrode is one in which the ECG records a positive (upward)

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deflection when the electrical impulse flows toward it and a negative (downward) deflection

when it flows away from it.

2. Unipolar Lead:

One in which the electrical potential at an exploring electrode is compared to a reference

point that averages electrical activity, rather than to that of another electrode. This single

electrode, termed the exploring electrode, is the positive electrode.

Limb Leads:

I, II, III, aVR, aVL, aVF explore the electrical activity in the heart in a frontal plane; i.e., the

orientation of the heart seen when looking directly at the anterior chest.

Standard Limb Leads:

I, II, III; bipolar, form a set of axes 60° apart

Lead I:

Composed of negative electrode on the right arm and positive electrode on the left arm.

Lead II:

Composed of negative electrode on the right arm and positive electrode on the left leg.

Lead III:

Composed of negative electrode on the left arm and positive electrode on the left leg.

Augmented Voltage Leads:

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aVR, aVL aVF; unipolar ; form a set of axes 60° apart but are rotated 30° from the axes of

the standard limb leads.

aVR: Exploring electrode located at the right shoulder.

aVL: Exploring electrode located at the left shoulder.

aVF: Exploring electrode located at the left foot.

Reference Point for Augmented Leads:

The opposing standard limb lead; i.e., that standard limb lead whose axis is perpendicular to

the particular augmented lead.

Chest Leads:

Vl, V2, V3, V4, V5, V6, explore the electrical activity of the heart in the horizontal plane;

i.e., as if looking down on a cross section of the body at the level of the heart. These are

exploring leads.

Reference Point for Chest Leads:

The point obtained by connecting the left arm, right arm, and left leg electrodes together.

Vl: Positioned in the 4th intercostal space just to the right of the sternum.

V2: Positioned in the 4th intercostal space just to the left of the sternum.

V3: Positioned halfway between V2 and V4.

V4: Positioned at the 5th intercostal space in the mid-clavicular line.

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V5: Positioned in the anterior axillary line at the same level as V4.

V6: Positioned in the mid axillary line at the same level as V4 and V5.

Vl and V2*: Monitor electrical activity of the heart from the anterior aspect, septum, and

right ventricle.

V3 and V4*: Monitor electrical activity of the heart from the anterior aspect.

V5 and V6*: Monitor electrical activity of the heart from the left ventricle and lateral aspect.

 

Rhythms(8)

The normal rhythms of the heart known as Sinus Rhythm.

The criteria for a Normal Sinus Rhythm is:

P-wave before each QRS with an interval of 0.12 to 0.20 seconds in duration. A QRS width of 0.04 to 0.12 seconds

Q-T interval of less the 0.40 seconds.

The rate for a normal sinus rhythm is 60 to 100 beats a minute

If the rate is below 60 beats a minute but the rest is the same it is a Sinus Bradycardia.

If the rate is between 100 to 150 beats a minute with the same intervals it is a Sinus

Tachycardia.

When the pattern becomes irregular with normal intervals it is a Sinus Arrhythmia

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Normal ECG(1)

Pulse rate lies between 60 and 100 beats/minute

Rhythm is regular except for minor variations with respiration.

P-R interval is the time required for completion of aerial depolarization; conduction

through the AV note, bundle of His, and bundle branches; and arrival at the

ventricular myocardial cells. The normal P-R interval is 0 12 to 0.20 seconds.

The QRS interval represents the time required for ventricular cells to depolarize. The

normal duration is 0.06 to 0.10 seconds.

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The Q-T interval is the time required for depolarization and repolarization of the

ventricles.

The time required is proportional to the heart rate. The faster the heart rate, the faster the

repolarization, and therefore the shorter the Q-T interval. With slow heart rates, the Q-T

interval is longer. The Q-T interval represents about 40% of the total time between the QRS

complexes (the R-R interval). In most cases, the Q-T interval lasts between 0.34 and 0.42

seconds.

Dimensions of Grids on ECG Paper:

Horizontal axis represents time. Large blocks are 0.2 seconds in duration, while small blocks

are 0.04 seconds in duration. Vertical axis represents voltage. Large blocks are 5mm, while

small blocks represent 1mm.

Indication(6)

An ECG is used to measure:

Any damage to the heart

How fast your heart is beating and whether it is beating normally

The effects of drugs or devices used to control the heart (such as a pacemaker)

The size and position of your heart chambers

An ECG is a very useful tool for determining whether a person has heart disease. Your doctor

may order this test if you have chest pain or palpitations.

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An ECG may be included as part of a routine examination in patients over age 40.

Caution(6)

Make sure your health care provider knows about all the medications you are taking, as some

can interfere with test results.

Exercising or drinking cold water immediately before an ECG may cause false results.

Risks(6)

There are no risks. No electricity is sent through the body, so there is no risk of shock.

Preparation(6)

You will be asked to remove your clothes, then you will be asked to lie down. The health care

provider will clean several areas on your arms, legs, and chest, and then attach small patches

called electrodes to the areas. It may be necessary to shave or clip some hair so the electrodes

stick to the skin.

The electrodes may feel cold when first applied. In rare cases, some people may develop a

rash or irritation where the patches were placed.

The number of patches used may vary.

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You usually need to remain still, and you may be asked to hold your breath for short periods

during the procedure. It is important to be relaxed and relatively warm during ECG recording.

Any movement, including muscle tremors such as shivering, can alter the results.

The electrodes are connected by wires to a machine that converts the electrical signals from

the heart into wavy lines, which are printed on paper and reviewed by the doctor.

Sometimes this test is done while you are exercising or under minimal stress to monitor

changes in the heart. This type of ECG is often called a stress test.

Results on ECG(6)

- Normal Results

Heart rate: 50 to 100 beats per minute

Heart rhythm: consistent and even

- Abnormal Results

Abnormal ECG results may be a sign of

Abnormal heart rhythms (arrhythmias)

Cardiac muscle defect

Congenital heart defect

Coronary artery disease

Ectopic heartbeat

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Enlargement of the heart

Faster-than-normal heart rate (tachycardia)

Heart valve disease

Inflammation of the heart (myocarditis)

Changes in the amount of electrolytes (chemicals in the blood)

Past heart attack

Present or impending heart attack

Slower-than-normal heart rate (bradycardia)

Additional conditions under which the test may be performed include the following:

Alcoholic cardiomyopathy

Anorexia nervosa

Aortic dissection

Aortic insufficiency

Aortic stenosis

Atrial fibrillation/flutter

Atrial myxoma

Atrial septal defect

Cardiac tamponade

Coarctation of the aorta

Complicated alcohol abstinence

(delirium tremens)

Coronary artery spasm

Digitalis toxicity

Dilated cardiomyopathy

Drug-induced lupus erythematosus

Familial periodic paralysis

Guillain-Barre

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Heart failure

Hyperkalemia

Hypertensive heart disease

Hypertrophic cardiomyopathy

Hypoparathyroidism

Idiopathic cardiomyopathy

Infective endocarditis

Insomnia

Ischemic cardiomyopathy

Left-sided heart failure

Lyme disease

Mitral regurgitation; acute

Mitral regurgitation; chronic

Mitral stenosis

Mitral valve prolapse

Multifocal atrial tachycardia

Narcolepsy

Obstructive sleep apnea

Paroxysmal supraventricular

tachycardia

Patent ductus arteriosus

Pericarditis

o Bacterial pericarditis

o Constrictive pericarditis

o Post-MI pericarditis

Peripartum cardiomyopathy

Primary amyloid

Primary hyperaldosteronism

Primary hyperparathyroidism

Primary pulmonary hypertension

Pulmonary embolus

Pulmonary valve stenosis

Restrictive cardiomyopathy

Right-sided heart failure

Sick sinus syndrome

Stable angina

Stroke 16

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Systemic lupus erythematosus

Tetralogy of Fallot

Thyrotoxic periodic paralysis

Transient ischemic attack (TIA)

Transposition of the great vessels

Tricuspid regurgitation

Type 1 diabetes

Type 2 diabetes

Unstable angina

Ventricular septal defect

Ventricular tachycardia

Wolff-Parkinson-White syndrome

II. ECHOCARDIOGRAPHY

Definition(10,11)

Echocardiography is a diagnostic test which uses ultrasound waves to create a moving picture

of the heart, to make images of the heart chambers, valves and surrounding structures. It can

measure cardiac output and is a sensitive test for inflammation around the heart (pericarditis).

It can also be used to detect abnormal anatomy or infections of the heart valves. The picture

is much more detailed than a plain x-ray image and involves no radiation exposure.

Echo can be used as part of a stress test and with an electrocardiogram (ECG) to help your

doctor learn more about your heart.

Types(13)

The different types of echocardiograms are:

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Transthoracic echocardiogram (TTE). This is the most common type. Views of the

heart are obtained by moving the transducer to different locations on your chest or

abdominal wall.

Stress echocardiogram. During this test, an echocardiogram is done both before and

after your heart is stressed either by having you exercise or by injecting a medicine

that makes your heart beat harder and faster. A stress echocardiogram is usually done

to find out if you might have decreased blood flow to your heart (coronary artery

disease, or CAD).

Doppler echocardiogram. This test is used to look at how blood flows through the

heart chambers, heart valves, and blood vessels. The movement of the blood reflects

sound waves to a transducer. The ultrasound computer then measures the direction

and speed of the blood flowing through your heart and blood vessels. Doppler

measurements may be displayed in black and white or in color.

Transesophageal echocardiogram (TEE). For this test, the probe is passed down the

esophagus instead of being moved over the outside of the chest wall. TEE shows

clearer pictures of your heart, because the probe is located closer to the heart and

because the lungs and bones of the chest wall do not block the sound waves produced

by the probe. A sedative and an anesthetic applied to the throat are used to make you

comfortable during this test.

Indication(11)

This test is performed to evaluate the valves and chambers of the heart in a noninvasive way. The echocardiogram allows doctors to diagnose, evaluate, and monitor:

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Heart murmurs Abnormal heart valves

The pumping function of the heart for people with heart failure

Damage to the heart muscle in patients who have had heart attacks

Infection in the sac around the heart (pericarditis)

Infection on or around the heart valves (infectious endocarditis)

The source of a blood clot or emboli after a stroke or TIA

Congenital heart disease

Atrial fibrillation

Pulmonary hypertension

Risks(11)

There are no known risks associated with this test.

Preparation(11)

You will be asked to remove your clothes from the waist up and lie on an examination table

on your back. Electrodes will be placed on your chest to allow for an echo to be done. A gel

will be spread on your chest and then the transducer will be applied. You will feel a slight

pressure on your chest from the transducer. You may be asked to breathe in a certain way or

to roll over onto your left side.

A trained sonographer performs the test, then your heart doctor interprets the results. An

instrument called a transducer that transmits high-frequency sound waves is placed on your

ribs near the breast bone and directed toward the heart.

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Additional images will be taken underneath and slightly to the left of your nipple (at the apex

of your heart). The transducer picks up the echoes of the sound waves and transmits them as

electrical impulses. The echocardiography machine converts these impulses into moving

pictures of the heart. The Doppler probe records the motion of the blood through the heart.

An echocardiogram allows doctors to see the heart beating, and to see many of the structures

of the heart. Occasionally, your lungs, ribs, or body tissue may prevent the sound waves and

echoes from providing a clear picture of heart function. If so, the sonographer may inject a

small amount of liquid (contrast) through an IV to better see the inside of the heart.

Very rarely, more invasive testing using special echocardiography probes may be necessary.

Your health care provider may choose to perform a TEE:

If the regular or transthoracic echocardiogram is unclear due to a barrel chest, lung

disease, or obesity

If a much clearer picture is needed of a certain area

With TEE, the back of your throat is numbed and a scope is inserted down your throat. On

the end of the scope is an ultrasonic device that an experienced technician will guide down to

the lower part of the esophagus. It is used to obtain a more clear two-dimensional

echocardiogram of your heart.

Results on Echocardiography(11)

- Normal Results

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A normal echocardiogram reveals normal heart valves and chambers and normal heart wall

movement.

- Abnormal Results

An abnormal echocardiogram can mean many things. Some abnormalities are very minor and

do not pose significant risks. Other abnormalities are signs of very serious heart disease that

will require further evaluation by a specialist. Therefore, it is very important to discuss the

results of your echocardiogram in depth with your health care provider.

Abnormal results may indicate heart valve disease, cardiomyopathy, pericardial effusion, or other heart abnormalities. This test may also be performed for the following conditions:

Alcoholic cardiomyopathy Aortic dissection

Aortic insufficiency

Aortic stenosis

Arrhythmias

Arterial embolism

Atrial fibrillation/flutter

Atrial myxoma

Atrial septal defect

Cardiac tamponade

Cardiomyopathy

Coarctation of the aorta

Heart attack

Heart failure

Hypertensive heart disease

Mitral regurgitation; acute

Mitral regurgitation; chronic

Mitral stenosis

Mitral valve prolapse

Patent ductus arteriosus

Pericarditis; bacterial

Pericarditis; constrictive

Pericarditis; post-MI

Peripartum cardiomyopathy

Primary amyloidosis

Pulmonary arterial hypertension

Pulmonary valve stenosis

Restrictive cardiomyopathy

Right-sided heart failure

Secondary systemic amyloidosis

Senile cardiac amyloidosis

Stroke

Tetralogy of Fallot

Transient ischemic attack (TIA)

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Conclusion

Both electrocardiography and echocardiography are very useful to help the doctors diagnose

problems on their patients’ heart. Its use for each indication. Altough both of them already

passed many year but those two are still very often used to help to diagnose besides interview,

physical examination and the, laboratory finding.

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References

1. R. Richter, MD. Basic Electrocardiography. Available at :

http://www.sh.lsuhsc.edu/fammed/OutpatientManual/BasicECG.htm . Accessed July 3,

2010.

2. Dubin, Dale: Rapid Interpretation of EKG’s, Third Edition. Cover Publishing Company,

Tampa, FL, 1981.

3. Grauer, Ken: 12 Lead EKGs A “Pocket Brain” for Easy Interpretation. KG/EKG Press,

Gainsville, FL.

4. Marriott, Henry JL: Practical Electrocardiography, Sixth Edition. Waverly Press, Inc,

Baltimore, MD. 1981.

5. Milhorn, Jr., HT: Electrocardiology for the Family Physician: Parts 1-5. Family Practice

Recertification. Vol 5, No’s 2,3,4,5 & 6. Months Feb, Mar, Apr, May & June,

respectively, 1983.

6. Basic ECG. Available at www.nlm.nih.gov/medlineplus/ency/article/003868.htm .

Accessed July 11, 2010.

7. Ganz L, Curtiss E. Electrocardiography. In: Goldman L, Ausiello D, eds. Cecil Medicine.

23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 52.

8. Aaron Segel. Sinus Rhythms. Available at

http://www.drsegal.com/medstud/ecg/Sinus.htm . Accessed July 11, 2010.

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9. Definition of Echocardiography. Available at

http://www.emedicinehealth.com/script/main/art.asp?articlekey=3182 . Accessed July 11,

2010.

10. Echocardiography. Available at

http://www.nhlbi.nih.gov/health/dci/Diseases/echo/echo_whatis.html . Accessed July 11,

2010.

11. Echocardiography. Available at

http://www.nlm.nih.gov/medlineplus/ency/article/003869.htm . Accessed July 11, 2010.

12. Connolly HM, Oh JK. Echocardiography. In: Libby P, Bonow RO, Mann DL, Zipes DP,

eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 8th ed.

Philadelphia, Pa: Saunders Elsevier;2007: chap 14.

13. Echocardiogram. Available at http://www.webmd.com/heart-disease/echocardiogram .

Accessed July 11, 2010.