diagnoses of cardiac arrhythmias through electrocardiographs

Diagnoses of Cardiac Diagnoses of Cardiac Arrhythmias Through Arrhythmias Through ElectrocardiographsElectrocardiographs

Greg HaiderGreg Haider

Self TutorialSelf Tutorial

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IndexIndex Importance of EKG InterpretationImportance of EKG Interpretation Review of the BasicsReview of the Basics The Motor of the Cardiovascular SystThe Motor of the Cardiovascular Syst

emem The EKG processThe EKG process

– 12-lead ECG12-lead ECG– Printout of a normal ratePrintout of a normal rate

Causes of ArrhythmiasCauses of Arrhythmias Diagnosis of Arrhythmias Using the Diagnosis of Arrhythmias Using the

EKGEKG Ethics of EKG DiagnosisEthics of EKG Diagnosis

Diagnosis of Cardiac Arrhythmias Through EKGs, By Greg Haider, EE5811 Biomedical Diagnosis of Cardiac Arrhythmias Through EKGs, By Greg Haider, EE5811 Biomedical InstrumentationInstrumentation

Importance of EKG Importance of EKG InterpretationInterpretation The underlying motivation and inspiration The underlying motivation and inspiration

for this tutorial lies in the fact that the for this tutorial lies in the fact that the early diagnosis of heart arrhythmias will early diagnosis of heart arrhythmias will save lives. Heart Arrhythmias are at fault save lives. Heart Arrhythmias are at fault for the degradation of thousands of lives. for the degradation of thousands of lives. Many of those affected by these Many of those affected by these arrhythmias do not even know that they arrhythmias do not even know that they have them, and therefore, are not being have them, and therefore, are not being treated. As the treatment for heart treated. As the treatment for heart disease continues to progress, the disease continues to progress, the diagnosis of the arrhythmias becomes diagnosis of the arrhythmias becomes more and more important. By catching more and more important. By catching heart arrhythmias through EKG’s, the heart arrhythmias through EKG’s, the lives of thousands of people can be lives of thousands of people can be improved. improved.

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Review of the BasicsReview of the Basics

The Heart is The Heart is composed of 4 composed of 4

Chambers. Each Chambers. Each having a specific having a specific job in the cardiac job in the cardiac cycle (click on the cycle (click on the

chart for more chart for more information)information)



Review of the BasicsReview of the Basics The Right AtriumThe Right Atrium

The Atriums are the gathering The Atriums are the gathering chambers of the heartchambers of the heart

The Right Atrium performs the The Right Atrium performs the job of gathering oxygen job of gathering oxygen depleted blood from the body.depleted blood from the body. Blood becomes oxygen depleted Blood becomes oxygen depleted

after nourishing the body, removing after nourishing the body, removing carbon dioxide from capillaries, carbon dioxide from capillaries, replacing it with oxygenreplacing it with oxygen

From the Right Atrium, blood is From the Right Atrium, blood is passed through one of the passed through one of the atrioventricular valves, the atrioventricular valves, the tricuspid, into the right tricuspid, into the right ventricle.ventricle.

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Review of the BasicsReview of the Basics The Left AtriumThe Left Atrium

The Atriums are the gathering The Atriums are the gathering chambers of the heartchambers of the heart

The Left Atrium performs the job The Left Atrium performs the job of gathering oxygen rich blood of gathering oxygen rich blood from the lungs.from the lungs. Oxygen rich blood is used to Oxygen rich blood is used to

nourish the body, removing carbon nourish the body, removing carbon dioxide from capillaries, replacing it dioxide from capillaries, replacing it with oxygenwith oxygen

From the Left Atrium, blood is From the Left Atrium, blood is passed through one of the passed through one of the atrioventricular valves, the atrioventricular valves, the Mitral valve, into the left Mitral valve, into the left ventricle.ventricle.



Review of the BasicsReview of the Basics The Right VentricleThe Right Ventricle

The ventricles are the pumping The ventricles are the pumping chambers of the heartchambers of the heart

The Right Ventricle performs the The Right Ventricle performs the job of pumping oxygen depleted job of pumping oxygen depleted blood to lungsblood to lungs The lungs oxygenate the blood, so The lungs oxygenate the blood, so

that it can be used again by the that it can be used again by the body for nourishingbody for nourishing

From the Right Ventricle, blood From the Right Ventricle, blood is passed through one of the is passed through one of the semilunar valves, the pulmonary semilunar valves, the pulmonary valve, into the pulmonary valve, into the pulmonary artery, to the lungsartery, to the lungs



Review of the BasicsReview of the Basics The Left VentricleThe Left Ventricle

The ventricles are the pumping The ventricles are the pumping chambers of the heartchambers of the heart

The Left Ventricle performs the The Left Ventricle performs the job of pumping oxygenated job of pumping oxygenated blood to the bodyblood to the body Oxygenated blood is sent to the Oxygenated blood is sent to the

body so that it can nourish the body so that it can nourish the body, removing carbon dioxide body, removing carbon dioxide from the capillariesfrom the capillaries

From the Left Ventricle, blood is From the Left Ventricle, blood is passed through one of the passed through one of the semilunar valves, the aortic semilunar valves, the aortic valve, into the Aorta, to the valve, into the Aorta, to the bodybody



The Motor of the The Motor of the Cardiovascular SystemCardiovascular System

Perimeter Layers of the HePerimeter Layers of the Heartart

Characteristics of the MyoCharacteristics of the Myocardiumcardium

Depolarization/RepolarizatiDepolarization/Repolarizationon

Hearts PacemakersHearts Pacemakers Conduction PathConduction Path



The Motor of the Cardiovascular The Motor of the Cardiovascular SystemSystem

Perimeter Layers of the HeartPerimeter Layers of the Heart– Pericardium and EpicardiumPericardium and Epicardium

Outer 2 layers of the heartOuter 2 layers of the heart Create a sack to hold pericardial fluidCreate a sack to hold pericardial fluid

– Like oil of an engine, the liquid center creates a frictionless Like oil of an engine, the liquid center creates a frictionless environment for the heart to pump, minimizing irritationenvironment for the heart to pump, minimizing irritation

Through a fibrous connection, the epicardium attaches to the Through a fibrous connection, the epicardium attaches to the myocardiummyocardium

– MyocardiumMyocardium Work Horse of the heart, the muscleWork Horse of the heart, the muscle

– EndocardiumEndocardium Frictionless inner layer, allowing blood to move as efficient as Frictionless inner layer, allowing blood to move as efficient as

possible through the heart and valvespossible through the heart and valves



Characteristics of the MyocardiumCharacteristics of the Myocardium– The myocardium consists of MyocardialThe myocardium consists of Myocardial

CellsCells These cells give the myocardium the “fuel” These cells give the myocardium the “fuel”

for pumpingfor pumping– From these cells, the electrical stimulus in the From these cells, the electrical stimulus in the

heart beginheart begin

– The cells branch and interlock such that when The cells branch and interlock such that when one cell is excited, the adjacent cell is exited, one cell is excited, the adjacent cell is exited, causing a chain reaction (domino effect)causing a chain reaction (domino effect)

– The stimulated myocardial cells descend The stimulated myocardial cells descend down the heart, causing the heart to down the heart, causing the heart to contract and circulate bloodcontract and circulate blood





Depolarization/RepolarizationDepolarization/Repolarization– Electrically charged Ions initiate the electrical pulses in the cellsElectrically charged Ions initiate the electrical pulses in the cells

sodium ions (Na)sodium ions (Na) calcium ions (Ca)calcium ions (Ca) potassium ions (K)potassium ions (K)

– When at rest (Not Contracted) Myocardial cells are negatively charged, consisting of internal potassium When at rest (Not Contracted) Myocardial cells are negatively charged, consisting of internal potassium ions and external sodium and calcium ionsions and external sodium and calcium ions

– DepolarizationDepolarization Depolarization is the contraction of the heart, caused by fast moving Na ions and slow moving Ca ions begin to Depolarization is the contraction of the heart, caused by fast moving Na ions and slow moving Ca ions begin to

move inward, while K ions move outmove inward, while K ions move out

– RepolarizationRepolarization When releasing, Na ions and Ca ions begin to trade with K ions to the normal state, this is known as repolarizationWhen releasing, Na ions and Ca ions begin to trade with K ions to the normal state, this is known as repolarization

– Together, Depolarization and Repolarization create the Action Potential PlotTogether, Depolarization and Repolarization create the Action Potential Plot


NextNextDiagnosis of Cardiac Arrhythmias Through EKGs, By Greg Haider, EE5811 Biomedical Diagnosis of Cardiac Arrhythmias Through EKGs, By Greg Haider, EE5811 Biomedical InstrumentationInstrumentation

Action Potential Caused by moving Action Potential Caused by moving ions in the myocardial cellsions in the myocardial cells– Phase 0Phase 0::

Rapid depolarization of Na ionsRapid depolarization of Na ions

– Phase 1 and 2Phase 1 and 2:: Slow depolarization of Ca ions, start of Slow depolarization of Ca ions, start of

repolarization of K ionsrepolarization of K ions

– Phase 3Phase 3:: Complete repolarizationComplete repolarization

– Phase 4:Phase 4: At restAt rest




PacemakersPacemakers– nodes of myocardial cells that do not rest, but nodes of myocardial cells that do not rest, but

continue to depolarize and repolarize at an continue to depolarize and repolarize at an inherent rate starting the conduction through inherent rate starting the conduction through the heartthe heart Sinoatrial Node (SA) – main pace makerSinoatrial Node (SA) – main pace maker Automaticiy Foci – Backup pacemakers, pace if a Automaticiy Foci – Backup pacemakers, pace if a

higher pacemaker fails to beathigher pacemaker fails to beat– Atrial foci: 60 – 80 bpmAtrial foci: 60 – 80 bpm– Junctional foci: 40 – 60 bpmJunctional foci: 40 – 60 bpm– Ventricular foci: 20 – 40 bpmVentricular foci: 20 – 40 bpm




Conduction PathConduction Path

•Click on the Click on the illustration for illustration for descriptiondescription

Purkinje Purkinje FibersFibers




Start of conduction Start of conduction pathpath– SA node is located in the SA node is located in the

upper right atriumupper right atrium

– This is the main pacemaker of This is the main pacemaker of heart, kick starting the heart, kick starting the depolarization of the atriums, depolarization of the atriums, forcing blood into the forcing blood into the ventriclesventricles

Conduction PathConduction PathBack To Back To IndexIndexBackBack


Atrioventricular Atrioventricular NodeNode– The AV node produces a The AV node produces a

pause in the electrical flow pause in the electrical flow through the heart, allowing through the heart, allowing the atria to completely the atria to completely contract and fill the ventriclescontract and fill the ventricles




His BundleHis Bundle– The His Bundle conducts the The His Bundle conducts the

depolarization down the depolarization down the septum into the ventricles septum into the ventricles and branches off into the right and branches off into the right and left Bundle Branchesand left Bundle Branches




Purkinje FibersPurkinje Fibers– These fibers stem off of the These fibers stem off of the

right and left bundle branches right and left bundle branches into the myocardium into the myocardium producing a strong explosion producing a strong explosion of current, pumping blood out of current, pumping blood out of the heartof the heart




The 12 lead EKG is the Most common form of EKG The 12 lead EKG is the Most common form of EKG MeasurementMeasurement

– This form of measurement consist so 6 limp leadsThis form of measurement consist so 6 limp leads

6 chest leads6 chest leads

The 6 limb leads are created with electrodes attached to both The 6 limb leads are created with electrodes attached to both arms and the left footarms and the left foot

– 3 Bipolar Limb leads3 Bipolar Limb leads

Each lead acts as both anode and cathodeEach lead acts as both anode and cathode

– 3 Augmented Limb leads3 Augmented Limb leads

Two leads set as anode, one as the cathodeTwo leads set as anode, one as the cathode

6 chest leads6 chest leads

– Positioned along the chest surrounding the heartPositioned along the chest surrounding the heart

– All chest leads are positively charged, allowingAll chest leads are positively charged, allowing

detection of the hearts electrical activitydetection of the hearts electrical activity

EKG Measurement EKG Measurement ProcessProcess



The 12-lead ECG allows the The 12-lead ECG allows the depolarization and depolarization and depolarization of the heart to depolarization of the heart to be detectedbe detected

Depolarization of the Atrium Depolarization of the Atrium produces the P-Wave on the produces the P-Wave on the EKG printoutEKG printout

The complex QRS-Wave of The complex QRS-Wave of the printout is produced the printout is produced through ventricular through ventricular depolarizationdepolarization

Finally, the EKG’s T-Wave is Finally, the EKG’s T-Wave is produced when the produced when the ventricular repolarizes.ventricular repolarizes.

Back To Back To IndexIndexBackBack EKG Measurement EKG Measurement

ProcessProcess


Causes of Heart Causes of Heart ArrhythmiasArrhythmias Unknown causesUnknown causes

– Too intermittent to diagnoseToo intermittent to diagnose Weak or lack of connection between Myocardial cellsWeak or lack of connection between Myocardial cells

– Caused by dead tissues or scars, infarctionsCaused by dead tissues or scars, infarctions Usually caused by extreme electrical impulses such as a heart Usually caused by extreme electrical impulses such as a heart

attack, also known as Myocardial Infarctionattack, also known as Myocardial Infarction Chemical ImbalancesChemical Imbalances

– Because the depolarization and repolarization of the heart Because the depolarization and repolarization of the heart relies the movement of ions, and imbalance of these ions can relies the movement of ions, and imbalance of these ions can produce abnormal beatsproduce abnormal beats

Sodium imbalanceSodium imbalance Calcium imbalanceCalcium imbalance

Electrical ConfusionElectrical Confusion– Again, usually caused by extreme electrical impulses that Again, usually caused by extreme electrical impulses that

unsynchronize the system, sometimes to the point that it is unsynchronize the system, sometimes to the point that it is unrecoverableunrecoverable



Diagnosis of Arrhythmias Diagnosis of Arrhythmias Using the EKGUsing the EKG

ArrhythmiasArrhythmias– First Degree Heart BlockFirst Degree Heart Block– Second Degree Heart BlockSecond Degree Heart Block– Sinus Rhythm Bradycardia and TachycSinus Rhythm Bradycardia and Tachyc

ardiaardia– HypercalcemiaHypercalcemia– HyperkalemiaHyperkalemia– Idioventricular RhythmIdioventricular Rhythm– Premature Atrial ContractionPremature Atrial Contraction– Premature Ventricular ContractionPremature Ventricular Contraction– Ventricular TachycardiaVentricular Tachycardia– Ventricular FibrillationVentricular Fibrillation– AsystoleAsystole




First Degree First Degree Heart BlockHeart Block

Normal EKG

First Degree Heart BlockFirst Degree Heart Block

First-degree heart block, or first-degree AV block, is the condition under which the First-degree heart block, or first-degree AV block, is the condition under which the electrical impulse moves through the AV node at a slower rate than normal. The electrical impulse moves through the AV node at a slower rate than normal. The cause of first degree heart block is not always known since in some cases it can be cause of first degree heart block is not always known since in some cases it can be intermittent. However, in many cases, it may be to a weakened conduction path intermittent. However, in many cases, it may be to a weakened conduction path caused by minor scarring of the tissue. caused by minor scarring of the tissue.

The time it takes for the impulse to get from the atria to the ventricles (the PR The time it takes for the impulse to get from the atria to the ventricles (the PR interval) should be less than about 0.2 seconds for a normal rhythm. If this time is interval) should be less than about 0.2 seconds for a normal rhythm. If this time is longer on the EKG, than the patient under test is experiencing first-degree heart longer on the EKG, than the patient under test is experiencing first-degree heart blockblock




• Second Degree Second Degree Heart BlockHeart Block

Normal EKG

Second Degree Heart BlockSecond Degree Heart Block

While first degree heart block may cause a physician to take a second look, it is While first degree heart block may cause a physician to take a second look, it is usually not harmful, producing a valid rate. However, second-degree heart block usually not harmful, producing a valid rate. However, second-degree heart block paints a different picture. In second-degree heart block, the AV junction moves so paints a different picture. In second-degree heart block, the AV junction moves so slow that some of the electrical impulses from the atrium never reach the slow that some of the electrical impulses from the atrium never reach the ventricles, meaning scarring is bad enough to completely disrupt the electrical ventricles, meaning scarring is bad enough to completely disrupt the electrical connection. This behavior will cause the EKG to produce a double P-wave.connection. This behavior will cause the EKG to produce a double P-wave.




• Sinus Rhythm Bradycardia Sinus Rhythm Bradycardia and Tachycardiaand Tachycardia

Normal EKG

BradycardiaBradycardia

Sinus Rhythm Bradycardia is the condition in which the patient’s rhythm is under 60 beats per Sinus Rhythm Bradycardia is the condition in which the patient’s rhythm is under 60 beats per minute. This condition is usually caused by the SA node firing too slow but could also be a sign that minute. This condition is usually caused by the SA node firing too slow but could also be a sign that another atrial foci has taken over pacing due to scarred tissue. However, the blockage of scar another atrial foci has taken over pacing due to scarred tissue. However, the blockage of scar tissue can usually be determined by the characteristics of the P wave, and would not be classified tissue can usually be determined by the characteristics of the P wave, and would not be classified under this condition. During sinus rhythm bradycardia, the R to R interval is lengthened, and at under this condition. During sinus rhythm bradycardia, the R to R interval is lengthened, and at times, the P wave is widened. times, the P wave is widened.

Sinus Rhythm Tachycardia is the opposite of Bradycardia, in which the internal heart rate is faster Sinus Rhythm Tachycardia is the opposite of Bradycardia, in which the internal heart rate is faster than that of a normal rate. During this condition, the SA node is firing too fast. When a patient is than that of a normal rate. During this condition, the SA node is firing too fast. When a patient is experiencing Sinus Tachycardia the heart rate of that patient is greater than 100bpm.experiencing Sinus Tachycardia the heart rate of that patient is greater than 100bpm.


TachycardiaTachycardia



• HypercalcemiaHypercalcemia Normal EKG

HypercalcemiaHypercalcemia

Hypercalcemia is a condition under which a patient is experiencing high levels of Hypercalcemia is a condition under which a patient is experiencing high levels of calcium in his/her body, a chemical imbalance. Because calcium plays such an calcium in his/her body, a chemical imbalance. Because calcium plays such an important role in the behavior of the heart, excess calcium can cause it to perform important role in the behavior of the heart, excess calcium can cause it to perform abnormally. With too much calcium, the interval between the final depolarization abnormally. With too much calcium, the interval between the final depolarization phase caused by calcium ions and the repolarization phase is shortened. The phase caused by calcium ions and the repolarization phase is shortened. The effects of Hypercalcemia are very difficult to see in some patients, however with a effects of Hypercalcemia are very difficult to see in some patients, however with a high enough content, the calcium can affect the heart such that the S-T interval is high enough content, the calcium can affect the heart such that the S-T interval is visibly shortened, or even invisible.visibly shortened, or even invisible.




• HyperkalemiaHyperkalemia Normal EKG

HyperkalemiaHyperkalemia

Hyperkalemia is the excessive amount of potassium in the body. Again, like Hyperkalemia is the excessive amount of potassium in the body. Again, like Calcium, Potassium is an important ion in the heart, affecting the behaviors of the Calcium, Potassium is an important ion in the heart, affecting the behaviors of the hearts depolarization. Therefore, large amounts of potassium in a patient’s body hearts depolarization. Therefore, large amounts of potassium in a patient’s body will affect the EKG. When large amounts of Potassium are found in the body, the T-will affect the EKG. When large amounts of Potassium are found in the body, the T-wave takes on a tent shaped form. As with Hypercalcemia, Hyperkalemia is a very wave takes on a tent shaped form. As with Hypercalcemia, Hyperkalemia is a very difficult condition to diagnose using an EKG printout due to the small effects that are difficult condition to diagnose using an EKG printout due to the small effects that are produced with the additional Ions.produced with the additional Ions.




• Idioventricular Idioventricular RhythmRhythm

Normal EKG

Idioventricular RhythmIdioventricular Rhythm

When one the ectopic foci, located at or above the atrioventricular node, fails to When one the ectopic foci, located at or above the atrioventricular node, fails to discharge, usually due to infracted tissue, atrial contraction never occurs. When discharge, usually due to infracted tissue, atrial contraction never occurs. When one of these foci fails to fire, a foci node within the ventricle will takeover, producing one of these foci fails to fire, a foci node within the ventricle will takeover, producing ventricular depolarization and repolarization. With the loss of Atrial contraction, the ventricular depolarization and repolarization. With the loss of Atrial contraction, the P-wave is absent from the EKG, showing only the QRS complex. Also, because the P-wave is absent from the EKG, showing only the QRS complex. Also, because the pacemaker is located in the ventricle, the QRS wave takes on a much different rate pacemaker is located in the ventricle, the QRS wave takes on a much different rate than that seen on a normal EKG. Because a separate automaticity foci is controlling than that seen on a normal EKG. Because a separate automaticity foci is controlling the rate, the rates of Idioventricular Rhythms are very slow – usually 30 to 40 beats the rate, the rates of Idioventricular Rhythms are very slow – usually 30 to 40 beats per minute. per minute.




• Premature Atrial Premature Atrial ContractionContraction

Normal EKG

Premature Atrial ContractionPremature Atrial Contraction

In many cases, physicians are unable to determine the cause of Premature Atrial In many cases, physicians are unable to determine the cause of Premature Atrial Contraction (PAC), however the signs of this condition are obvious on the EKG. In Contraction (PAC), however the signs of this condition are obvious on the EKG. In PAC, an SA node kicks off atrial contraction soon after ventricular repolarization, PAC, an SA node kicks off atrial contraction soon after ventricular repolarization, producing a strange T-P interval from one beat to the next. The heart rate usually producing a strange T-P interval from one beat to the next. The heart rate usually picks up as normal, but with a shift in phase.picks up as normal, but with a shift in phase.




Normal EKG

Premature Ventricular Premature Ventricular ContractionContraction

Premature Ventricular Contraction is the escape of a ventricular automaticity foci Premature Ventricular Contraction is the escape of a ventricular automaticity foci pace, while the SA or other ectopic foci are performing their duties correctly; there pace, while the SA or other ectopic foci are performing their duties correctly; there is no block that makes it necessary for this foci to fire. In this case, the ventricle is no block that makes it necessary for this foci to fire. In this case, the ventricle contracts before the atrial pacemaker has an opportunity to initiate the normal rate. contracts before the atrial pacemaker has an opportunity to initiate the normal rate. Therefore, this condition is seen on the EKG as a missed P-wave, and an irregular, Therefore, this condition is seen on the EKG as a missed P-wave, and an irregular, widened QRS complex.widened QRS complex.


• Premature Ventricular Premature Ventricular ContractionContraction



• Ventricular Ventricular TachycardiaTachycardia

Normal EKG

Ventricular TachycardiaVentricular Tachycardia

Ventricular tachycardia is defined as three or more beats of ventricular origin in Ventricular tachycardia is defined as three or more beats of ventricular origin in succession at a rate greater than 100 beats per minute. There are no normal-succession at a rate greater than 100 beats per minute. There are no normal-looking QRS complexes and the rhythm is usually regular, but on occasion it may be looking QRS complexes and the rhythm is usually regular, but on occasion it may be modestly irregular. Much like PVC, under the condition of ventricular tachycardia, modestly irregular. Much like PVC, under the condition of ventricular tachycardia, the SA is still depolarizing the atria, however in ventricular tachycardia a ventricular the SA is still depolarizing the atria, however in ventricular tachycardia a ventricular foci node is controlling the pace at a rate faster or equal to that of the atria. foci node is controlling the pace at a rate faster or equal to that of the atria. Because the ventricle is in refractory when the atria depolarization is passed to the Because the ventricle is in refractory when the atria depolarization is passed to the atrioventricular node, this stimulus has no effect on the synching the two rates. The atrioventricular node, this stimulus has no effect on the synching the two rates. The ventricular depolarization far outweighs the atria depolarization, dominating the ventricular depolarization far outweighs the atria depolarization, dominating the EKG screen.EKG screen.




• Ventricular Ventricular FibrillationFibrillation

Normal EKG

Ventricular FibrillationVentricular Fibrillation

Ventricular fibrillation is caused by the total disorder of ventricular foci. This Ventricular fibrillation is caused by the total disorder of ventricular foci. This condition is caused by extreme electrical stress in the heart, scrambling the rhythm condition is caused by extreme electrical stress in the heart, scrambling the rhythm of the heart. Under these conditions, the ventricle is attempting to contract at of the heart. Under these conditions, the ventricle is attempting to contract at different rates, at different locations. This chaotic depolarization results in a different rates, at different locations. This chaotic depolarization results in a ventricular fibrillation, or a quiver, rather than a rhythm, resulting in very little blood ventricular fibrillation, or a quiver, rather than a rhythm, resulting in very little blood flow from the heart. Ventricular fibrillation is shown on the EKG as very small, flow from the heart. Ventricular fibrillation is shown on the EKG as very small, random pulses.random pulses.




Normal EKG

AsystoleAsystole

The simplest EKG reading to determine is that of Asystole, or death. At the time of The simplest EKG reading to determine is that of Asystole, or death. At the time of Asystole, the heart is fully depolarized, in both the atrial and the ventricular, with no Asystole, the heart is fully depolarized, in both the atrial and the ventricular, with no attempts to repolarize. Because there is no electrical activity in the heart, there is attempts to repolarize. Because there is no electrical activity in the heart, there is no EKG surge caused by the lead connections. The EKG reading is just what one no EKG surge caused by the lead connections. The EKG reading is just what one would expect under these conditions, flat. would expect under these conditions, flat.


• AsystoleAsystole


Medical Ethics of Medical Ethics of EKG DiagnosisEKG Diagnosis

The EKG process itself appears The EKG process itself appears harmless, however every procedure harmless, however every procedure involves an ethical decisioninvolves an ethical decision– Ethical Question:Ethical Question:

Is it necessary?Is it necessary?– May Cause Physical DiscomfortMay Cause Physical Discomfort

Leads must be attached to the bodyLeads must be attached to the body May Cause Mental DiscomfortMay Cause Mental Discomfort

– EmbarrassmentEmbarrassment– FearFear



Ethics of treating arrhythmias following a DiagnosisEthics of treating arrhythmias following a Diagnosis– ComfortComfort

Drug treatment versus possible implantable deviceDrug treatment versus possible implantable device

– Life CircumstancesLife Circumstances Will this require monthly checkups?Will this require monthly checkups?

– Single parentSingle parent– Traveling positionTraveling position– Fear of hospitalsFear of hospitals

– AgeAge ElderlyElderly

– Would surgery produce more risk than the condition itself?Would surgery produce more risk than the condition itself?

YoungYoung– Because patient is still growing, should other alternative treatment be decided on if an implantable is the Because patient is still growing, should other alternative treatment be decided on if an implantable is the

usual treatment?usual treatment?

– FinancesFinances Is the patient insured?Is the patient insured? Will the patient be retiring, will they keep insurance?Will the patient be retiring, will they keep insurance? Many heart conditions are chronic, therefore the treatment will be with them forever, can they Many heart conditions are chronic, therefore the treatment will be with them forever, can they

not only afford it now, but what about 10, 20, or even 50 years down the roadnot only afford it now, but what about 10, 20, or even 50 years down the road

Each decision must be made on a patient to patient basesEach decision must be made on a patient to patient bases– The best treatment is not always the right treatmentThe best treatment is not always the right treatment

Do good versus Do rightDo good versus Do right

Medical Ethics of Medical Ethics of EKG DiagnosisEKG Diagnosis



diagnoses of cardiac arrhythmias through electrocardiographs

Documents

oxygen rich blood

bodyoxygenated blood

basicsthe heart

left ventricle

heartthe right ventricle

heartthe right atrium

left atrium

pumping chambers