Difference between revisions of "Clinical Disorders"

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==Medication==
 
==Medication==
 
===Digoxin===
 
===Digoxin===
[[Image:med_digitalis.png|thumb|300px|Typical for digoxin intoxication is the odd shaped ST-depression]]
+
[[Image:med_digitalis.png|thumb|300px|Typical for digoxin intoxication is the oddly shaped ST-depression]]
 
ECG changes typical for digoxin intoxication (digoxin = Lanoxin) are:
 
ECG changes typical for digoxin intoxication (digoxin = Lanoxin) are:
*odd shaped ST-depression.  
+
*oddly shaped ST-depression.  
 
*T-wave flat, negative or biphasic
 
*T-wave flat, negative or biphasic
 
*Short QT interval
 
*Short QT interval
 
*Increased u-wave amplitude
 
*Increased u-wave amplitude
 
*Prolonged PR-interval
 
*Prolonged PR-interval
*Brady-arrhytmias:
+
*Bradyarrhythmias:
**Sinusbradycardia
+
**Sinus bradycardia
 
**AV block. Including complete AV block and Wenkebach.
 
**AV block. Including complete AV block and Wenkebach.
 
*Tachyarrhythmias:
 
*Tachyarrhythmias:
 
**Junctional tachycardia
 
**Junctional tachycardia
**Atrialtachycardia
+
**Atrial tachycardia
 
**Ventricular ectopia, bigemini, monomorphic ventricular tachycardia, bidirectional ventricular tachycardia
 
**Ventricular ectopia, bigemini, monomorphic ventricular tachycardia, bidirectional ventricular tachycardia
  
Intoxication can lead to a SA-block or AV-block, sometimes in combination with a tachycardia. '''NB''' these effects are increased by hypokaliemia. In extreme high concentrations rhythmdisturbances (''ventricular tachycardia, ventricular fibrillation, atrial fibrillation'') may develop.
+
Intoxication can lead to an SA-block or AV-block, sometimes in combination with tachycardia. '''NB''' these effects are increased by hypokalemia. In extreme high concentrations rhythm disturbances (''ventricular tachycardia, ventricular fibrillation, atrial fibrillation'') may develop.
 
{{clr}}
 
{{clr}}
===Anti-arhythmics===
+
===Antiarrhythmics===
* '''anti-arhythmics:''' These may lead to several ECG-changes;
+
* '''anti-arrhythmics:''' These may lead to several ECG-changes;
**broad and irregulair P-wave
+
**broad and irregular P-wave
**broad QRS-complex
+
**broad QRS complex
**prolonged QT-interval (brady-, tachycardia, AV-block, ventricular tachycardia)
+
**prolonged QT interval (brady-, tachycardia, AV-block, ventricular tachycardia)
 
**prominent U-wave
 
**prominent U-wave
 
**In case of intoxication, the above mentioned characteristics are more prominent
 
**In case of intoxication, the above mentioned characteristics are more prominent
  
Additionally, several arrhtythmias can be seen.
+
Additionally, several arrhthytmias can be seen.
  
 
=== Nortriptyline intoxication ===
 
=== Nortriptyline intoxication ===
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{|
 
{|
 
|
 
|
[[Image:ECG_nortr_intox.png|thumb|left|300px|An example of severe nortriptyline intoxication. The inhibitory effect of the sodiumchannel manifests as a broadened QRS complex and a prolonged QT interval.]]
+
[[Image:ECG_nortr_intox.png|thumb|left|300px|An example of severe nortriptyline intoxication. The inhibitory effect of the sodium channel manifests as a broadened QRS complex and a prolonged QT interval.]]
 
|
 
|
 
[[Image:ECG_TCA_intox.jpg|thumb|left|300px| Another example of severe nortriptyline intoxication.]]
 
[[Image:ECG_TCA_intox.jpg|thumb|left|300px| Another example of severe nortriptyline intoxication.]]
Line 48: Line 48:
 
{|
 
{|
 
|
 
|
[[Image:ECG_amitr_OD_during.jpg|thumb|300px| An example of a severe amitriptylin intoxication. The inhibitory effect of the sodiumchannel manifests as a broadened QRS complex.]]
+
[[Image:ECG_amitr_OD_during.jpg|thumb|300px| An example of a severe amitriptyline intoxication. The inhibitory effect on the sodium channel manifests as a broadened QRS complex.]]
 
|
 
|
 
[[Image:ECG_amitr_OD_before.jpg|thumb|300px| An ECG of the same patient before the intoxication.]]
 
[[Image:ECG_amitr_OD_before.jpg|thumb|300px| An ECG of the same patient before the intoxication.]]
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==Myocarditis==
 
==Myocarditis==
  
[[w:Myocarditis|Myocarditis]] is an inflammation of the myocardium and the interstitium. The symptoms are faint chestpain, abnormal heartrate and progressive heartfailure. It can be caused by several factors: viral, bacterial, fungi, parasites, spirochaet, auto-immune, borreliosis (Lyme's disease) and HIV/AIDS.  
+
[[w:Myocarditis|Myocarditis]] is an inflammation of the myocardium and the interstitium. The symptoms are faint chest pain, abnormal heart rate and progressive heart failure. It can be caused by several factors: viruses, bacteria, fungi, parasites, spirochaetes, auto-immune reactions, borreliosis (Lyme's disease) and HIV/AIDS.  
  
Acute peri/myocarditis causes aspecific ST changes. These can be accompanied with supraventricular and ventricular rhythmdisturbances and T-wave abnormalities.
+
Acute peri/myocarditis causes nonspecific ST segment changes. These can be accompanied by supraventricular and ventricular rhythm disturbances and T-wave abnormalities.
  
 
==Pulmonary embolism==
 
==Pulmonary embolism==
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==Chronic pulmonary disease pattern==
 
==Chronic pulmonary disease pattern==
The ECG shows low voltaged QRS-complexes in leads I, II, and III and a right axisdeviation. This is caused by the increased pressure on the right chamber. This leads to right ventricular hypertrophy.
+
The ECG shows low voltage QRS complexes in leads I, II, and III and a right axis deviation. This is caused by the increased pressure on the right chamber. This leads to right ventricular hypertrophy.
  
 
==Pacemaker==
 
==Pacemaker==
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==Tamponade==
 
==Tamponade==
 
[[Image:ECG000028.jpg|thumb|Electrical alternans on the ECG]]
 
[[Image:ECG000028.jpg|thumb|Electrical alternans on the ECG]]
In case of a tamponade, fluid collects in the pericardium. As the pericardium is stiff, the heart is compressed resulting in relaxation, and thus, filling difficulties. This is a potential life-threatening situation and should be treated with pericardiocenteses, which is drainage of the fluid. Tamponade can be the results of pericarditis or myocarditis. Also, after a myocardial infarction a tamponade may develop, this is called Dresslers' Syndrome. In case of cancer, pericardial fluid may develop. This is usually caused by a Pericarditis carcinomatosa, meaning that the cancer has spread to the pericardium
+
In case of tamponade, fluid collects in the pericardium. As the pericardium is stiff, the heart is compressed, resulting in filling difficulties. This is a potentially life-threatening situation and should be treated with pericardiocentesis, which is drainage of the fluid. Tamponade can be the result of pericarditis or myocarditis. Also, after a myocardial infarction a tamponade may develop; this is called Dresslers' Syndrome. In case of cancer,increased pericardial fluid may develop. This is usually caused by pericarditis carcinomatosis, meaning that the cancer has spread to the pericardium
  
 
The ECG shows:
 
The ECG shows:
 
*Sinus tachycardia
 
*Sinus tachycardia
*Low-voltaged QRS complexes [[microvoltages]]
+
*Low-voltage QRS complexes [[microvoltages]]
 
*Alternation of the QRS complexes, usually in a 2:1 ratio. Electrical alternans can also be seen in myocardial ischemia, acute pulmonary embolism, and tachyarrhythmias
 
*Alternation of the QRS complexes, usually in a 2:1 ratio. Electrical alternans can also be seen in myocardial ischemia, acute pulmonary embolism, and tachyarrhythmias
 
*PR segment depression (this can also be observed in an [[Ischemia#Atriaal_.2F_boezem_infarct|atrial infarction]])
 
*PR segment depression (this can also be observed in an [[Ischemia#Atriaal_.2F_boezem_infarct|atrial infarction]])
Line 85: Line 85:
  
 
==Ventricular Aneurysm==
 
==Ventricular Aneurysm==
The ECG pattern suggests an acute MI. All classical signs of MI may occur:; Q-waves, ST-elevations (>1mm, >4 weeks present)and T-wave inversions are present. To exclude an acute MI, comparison with old ECG's is compulsory (MI has occurred years before).
+
The ECG pattern suggests an acute MI. All classical signs of MI may occur:; Q waves, ST segment elevations (>1mm, >4 weeks present)and T wave inversions are present. To exclude an acute MI, comparison with old ECG's is compulsory (MI has occurred years before).
  
 
==Dilated Cardiomyopathy==
 
==Dilated Cardiomyopathy==
Often, a LBBB or broadened QRS-complex can be seen. Additionally, aspecific ST changes are present with signs of left atrial enlargement.
+
Often, a LBBB or broadened QRS-complex can be seen. Additionally, nonspecific ST segment changes are present with signs of left atrial enlargement.
  
 
==Hypertrophic Obstructive Cardiomyopathy==
 
==Hypertrophic Obstructive Cardiomyopathy==
A HOCM is an heditary illness.
+
A HOCM is an hereditary illness.
 
On the ECG there are signs of [[hypertrophy|left ventricular hypertrophy]] and [[P wave morphology|left atrial enlargement]].
 
On the ECG there are signs of [[hypertrophy|left ventricular hypertrophy]] and [[P wave morphology|left atrial enlargement]].
  
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<div style="float:right">
 
<div style="float:right">
 
<gallery>
 
<gallery>
Image:osborne_ecg.jpg|A 12 lead ECG of a patient with a body temperature of 32 degrees Celsius. Note the sinusbradycardia, the prolonged QT interval (QTc is not prolonged) and the Osborne J wave, most prominantly in leads V2-V5
+
Image:osborne_ecg.jpg|A 12 lead ECG of a patient with a body temperature of 32 degrees Celsius. Note the sinus bradycardia, the prolonged QT interval (QTc is not prolonged) and the Osborne J wave, most prominently in leads V2-V5
 
Image:JJ0001.jpg|An ECG of a patient with a body temperature of 28 degrees Celsius.
 
Image:JJ0001.jpg|An ECG of a patient with a body temperature of 28 degrees Celsius.
 
</gallery>
 
</gallery>
 
</div>
 
</div>
 
In hypothermia a number of specific changes can be seen;<cite>hypoth</cite>
 
In hypothermia a number of specific changes can be seen;<cite>hypoth</cite>
* sinubradycardia
+
* Sinus bradycardia
* prolonged QTc-interval
+
* Prolonged QTc-interval
* ST-elevation (inferior and left precordial leads)
+
* ST segment elevation (inferior and left precordial leads)
 
* Osborne-waves (slow deflexions at the end of the QRS-complex)
 
* Osborne-waves (slow deflexions at the end of the QRS-complex)
  
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==ECG changes after neurologic events==
 
==ECG changes after neurologic events==
 
[[Image:ECG_SAB.png|thumb| ECG of a 74 year old patient with a subarachnoid hemorrhage. Note the negative T-waves and the prolonged QT interval.]]
 
[[Image:ECG_SAB.png|thumb| ECG of a 74 year old patient with a subarachnoid hemorrhage. Note the negative T-waves and the prolonged QT interval.]]
In 1938, Aschenbrenner <cite>Aschenbrenner</cite> noted that repolarisation abnormalities may occur after increased intracranial pressure. Since then, many publications have occurred discribing ECG changes after acute neurological events.
+
In 1938, Aschenbrenner <cite>Aschenbrenner</cite> noted that repolarization abnormalities may occur after increased intracranial pressure. Since then, many publications have described ECG changes after acute neurological events.
  
 
De ECG changes that may occur are:  
 
De ECG changes that may occur are:  
*q-waves
+
*Q waves
*ST-elevations,  
+
*ST segment elevations,  
*ST-depressions,  
+
*ST segment depressions,  
*T-wave changes. Large negative T waves over the precordial leads are observed frequently.
+
*T wave changes. Large negative T waves over the precordial leads are observed frequently.
*prolonged QT-interval.
+
*Prolonged QT-interval.
*prominent u-waves.
+
*Prominent u-waves.
  
These abnormalites are frequently seen after [[w:Subarachnoid_hemorrhage|subarachnoid_hemorrhage (SAH)]] (if measured serially, almost every SAH patients has at least one abnormal ECG.), but also in [[w:Subdural_haematoma|subdural haematoma]], ischemic [[w:Cerebrovascular_accident|CVA]]'s, [[w:Brain_tumor|brain Tumors]], [[w:Guillain-Barre|Guillain Barré]], [[w:Epilepsy|epilepsy]] and [[w:Migraine|migraine]]. The ECG changes are generally reversible and have linited prognostic value. However, the ECG changes can be accompanied with myocardial damage and echocardiographic changes. The cause of the ECG changes is not yet clear. The most common hypothesis is that of a neurotramittor "catecholaminestorm" caused by sympathtic stimulation.
+
These abnormalities are frequently seen after [[w:Subarachnoid_hemorrhage|subarachnoid_hemorrhage (SAH)]] (if measured serially, almost every SAH patients has at least one abnormal ECG.), but also in [[w:Subdural_hematoma|subdural hematoma]], ischemic [[w:Cerebrovascular_accident|CVA]]'s, [[w:Brain_tumor|brain Tumors]], [[w:Guillain-Barre|Guillain Barré]], [[w:Epilepsy|epilepsy]] and [[w:Migraine|migraine]]. The ECG changes are generally reversible and have limited prognostic value. However, the ECG changes can be accompanied with myocardial damage and echocardiographic changes. The cause of the ECG changes is not yet clear. The most common hypothesis is that of a neurotramitter "catecholamine storm" caused by sympathetic stimulation.
  
 
==Cardiac contusion==
 
==Cardiac contusion==
Cardiac contusion (in latin: contusio cordis or commotio cordis) is caused by a blunt trauma to the chest, often caused by a car- or motorbikeaccident or in martial arts<cite>Maron</cite>. Rhythmdisturbances may occur and even heartfailure. Diagnosis is made using echocardiography and laboratorytesting for cardiac enzymes.  
+
Cardiac contusion (in latin: contusio cordis or commotio cordis) is caused by a blunt trauma to the chest, often caused by a car or motorbike accident or in martial arts<cite>Maron</cite>. Rhythm disturbances and even heart failure can occur. Diagnosis is made using echocardiography and laboratory testing for cardiac enzymes.  
 
Possible ECG changes are:<cite>Sybrandy</cite>
 
Possible ECG changes are:<cite>Sybrandy</cite>
  
Line 142: Line 142:
 
*AV delay(1st, 2nd, and 3rd degree AV blok)
 
*AV delay(1st, 2nd, and 3rd degree AV blok)
 
'''Arrhythmias'''
 
'''Arrhythmias'''
*Sinustachycardia
+
*Sinus tachycardia
 
*Atrial and ventricular extrasystoles
 
*Atrial and ventricular extrasystoles
 
*Atrial fibrillation
 
*Atrial fibrillation
 
*Ventricular tachycardia
 
*Ventricular tachycardia
 
*[[Arrhythmias#Ventricular fibrillation|Ventricular fibrillation]]
 
*[[Arrhythmias#Ventricular fibrillation|Ventricular fibrillation]]
*Sinusbradycardia
+
*Sinus bradycardia
*Atriala tachycardia
+
*Atrial tachycardia
  
 
==Lown Ganong Levine Syndrome==
 
==Lown Ganong Levine Syndrome==
 
The Lown Ganong Levine Syndrome is a pre-excitation syndrome in which the atria are connected to the lower part of the AV node or bundle of His. On the ECG:
 
The Lown Ganong Levine Syndrome is a pre-excitation syndrome in which the atria are connected to the lower part of the AV node or bundle of His. On the ECG:
* short PR interval, < 120 ms
+
* Short PR interval, < 120 ms
* normal QRS complex
+
* Normal QRS complex
* no delta wave
+
* No delta wave
==Left and right bundelbranch block==
+
==Left and right bundle branch block==
 
See: [[Conduction_delay|Conduction delay]]
 
See: [[Conduction_delay|Conduction delay]]
  

Revision as of 19:38, 22 January 2010

Author(s) I.A.C. van der Bilt, MD
Moderator T.T. Keller
Supervisor
some notes about authorship

Medication

Digoxin

Typical for digoxin intoxication is the oddly shaped ST-depression

ECG changes typical for digoxin intoxication (digoxin = Lanoxin) are:

  • oddly shaped ST-depression.
  • T-wave flat, negative or biphasic
  • Short QT interval
  • Increased u-wave amplitude
  • Prolonged PR-interval
  • Bradyarrhythmias:
    • Sinus bradycardia
    • AV block. Including complete AV block and Wenkebach.
  • Tachyarrhythmias:
    • Junctional tachycardia
    • Atrial tachycardia
    • Ventricular ectopia, bigemini, monomorphic ventricular tachycardia, bidirectional ventricular tachycardia

Intoxication can lead to an SA-block or AV-block, sometimes in combination with tachycardia. NB these effects are increased by hypokalemia. In extreme high concentrations rhythm disturbances (ventricular tachycardia, ventricular fibrillation, atrial fibrillation) may develop.

Antiarrhythmics

  • anti-arrhythmics: These may lead to several ECG-changes;
    • broad and irregular P-wave
    • broad QRS complex
    • prolonged QT interval (brady-, tachycardia, AV-block, ventricular tachycardia)
    • prominent U-wave
    • In case of intoxication, the above mentioned characteristics are more prominent

Additionally, several arrhthytmias can be seen.

Nortriptyline intoxication

An example of severe nortriptyline intoxication. The inhibitory effect of the sodium channel manifests as a broadened QRS complex and a prolonged QT interval.
Another example of severe nortriptyline intoxication.


Amitriptyline intoxication

An example of a severe amitriptyline intoxication. The inhibitory effect on the sodium channel manifests as a broadened QRS complex.
An ECG of the same patient before the intoxication.


Pericarditis

Pericarditis

Myocarditis

Myocarditis is an inflammation of the myocardium and the interstitium. The symptoms are faint chest pain, abnormal heart rate and progressive heart failure. It can be caused by several factors: viruses, bacteria, fungi, parasites, spirochaetes, auto-immune reactions, borreliosis (Lyme's disease) and HIV/AIDS.

Acute peri/myocarditis causes nonspecific ST segment changes. These can be accompanied by supraventricular and ventricular rhythm disturbances and T-wave abnormalities.

Pulmonary embolism

See the chapter Pulmonary Embolism

Chronic pulmonary disease pattern

The ECG shows low voltage QRS complexes in leads I, II, and III and a right axis deviation. This is caused by the increased pressure on the right chamber. This leads to right ventricular hypertrophy.

Pacemaker

See the chapter Pacemaker

Tamponade

Electrical alternans on the ECG

In case of tamponade, fluid collects in the pericardium. As the pericardium is stiff, the heart is compressed, resulting in filling difficulties. This is a potentially life-threatening situation and should be treated with pericardiocentesis, which is drainage of the fluid. Tamponade can be the result of pericarditis or myocarditis. Also, after a myocardial infarction a tamponade may develop; this is called Dresslers' Syndrome. In case of cancer,increased pericardial fluid may develop. This is usually caused by pericarditis carcinomatosis, meaning that the cancer has spread to the pericardium

The ECG shows:

  • Sinus tachycardia
  • Low-voltage QRS complexes microvoltages
  • Alternation of the QRS complexes, usually in a 2:1 ratio. Electrical alternans can also be seen in myocardial ischemia, acute pulmonary embolism, and tachyarrhythmias
  • PR segment depression (this can also be observed in an atrial infarction)


Ventricular Aneurysm

The ECG pattern suggests an acute MI. All classical signs of MI may occur:; Q waves, ST segment elevations (>1mm, >4 weeks present)and T wave inversions are present. To exclude an acute MI, comparison with old ECG's is compulsory (MI has occurred years before).

Dilated Cardiomyopathy

Often, a LBBB or broadened QRS-complex can be seen. Additionally, nonspecific ST segment changes are present with signs of left atrial enlargement.

Hypertrophic Obstructive Cardiomyopathy

A HOCM is an hereditary illness. On the ECG there are signs of left ventricular hypertrophy and left atrial enlargement.

Electrolyte disturbances

See chapter: electrolyte disturbances

Hypothermia

An Osborne J wave

In hypothermia a number of specific changes can be seen;[1]

  • Sinus bradycardia
  • Prolonged QTc-interval
  • ST segment elevation (inferior and left precordial leads)
  • Osborne-waves (slow deflexions at the end of the QRS-complex)


ECG changes after neurologic events

ECG of a 74 year old patient with a subarachnoid hemorrhage. Note the negative T-waves and the prolonged QT interval.

In 1938, Aschenbrenner [2] noted that repolarization abnormalities may occur after increased intracranial pressure. Since then, many publications have described ECG changes after acute neurological events.

De ECG changes that may occur are:

  • Q waves
  • ST segment elevations,
  • ST segment depressions,
  • T wave changes. Large negative T waves over the precordial leads are observed frequently.
  • Prolonged QT-interval.
  • Prominent u-waves.

These abnormalities are frequently seen after subarachnoid_hemorrhage (SAH) (if measured serially, almost every SAH patients has at least one abnormal ECG.), but also in subdural hematoma, ischemic CVA's, brain Tumors, Guillain Barré, epilepsy and migraine. The ECG changes are generally reversible and have limited prognostic value. However, the ECG changes can be accompanied with myocardial damage and echocardiographic changes. The cause of the ECG changes is not yet clear. The most common hypothesis is that of a neurotramitter "catecholamine storm" caused by sympathetic stimulation.

Cardiac contusion

Cardiac contusion (in latin: contusio cordis or commotio cordis) is caused by a blunt trauma to the chest, often caused by a car or motorbike accident or in martial arts[3]. Rhythm disturbances and even heart failure can occur. Diagnosis is made using echocardiography and laboratory testing for cardiac enzymes. Possible ECG changes are:[4]

Not-specific changes

  • Pericarditis-like ST elevation or PTa depression
  • Prolonged QT interval

Myocardial damage

  • New Q waves
  • ST-T segment elevation or depression

Conduction delay

  • Right bundelbranchblok
  • Fascicular blok
  • AV delay(1st, 2nd, and 3rd degree AV blok)

Arrhythmias

  • Sinus tachycardia
  • Atrial and ventricular extrasystoles
  • Atrial fibrillation
  • Ventricular tachycardia
  • Ventricular fibrillation
  • Sinus bradycardia
  • Atrial tachycardia

Lown Ganong Levine Syndrome

The Lown Ganong Levine Syndrome is a pre-excitation syndrome in which the atria are connected to the lower part of the AV node or bundle of His. On the ECG:

  • Short PR interval, < 120 ms
  • Normal QRS complex
  • No delta wave

Left and right bundle branch block

See: Conduction delay


Cocaine Intoxication

|JJ00001.jpg


References

  1. Solomon A, Barish RA, Browne B, and Tso E. The electrocardiographic features of hypothermia. J Emerg Med. 1989 Mar-Apr;7(2):169-73. PubMed ID:2738372 | HubMed [hypoth]
  2. Aschenbrenner R, Bodechtel G, Über Ekg.-Veränderungen bei Hirntumorkranken. Journal of Molecular Medicine, 17, 9, 2/1/1938, Pages 298-302, http://dx.doi.org/10.1007/BF01778563

    [Aschenbrenner]
  3. Ashrafian H. Sudden death in young athletes. N Engl J Med. 2003 Dec 18;349(25):2464-5; author reply 2464-5. DOI:10.1056/NEJM200312183492518 | PubMed ID:14681516 | HubMed [Maron]
  4. Sybrandy KC, Cramer MJ, and Burgersdijk C. Diagnosing cardiac contusion: old wisdom and new insights. Heart. 2003 May;89(5):485-9. DOI:10.1136/heart.89.5.485 | PubMed ID:12695446 | HubMed [Sybrandy]
  5. Rodger M, Makropoulos D, Turek M, Quevillon J, Raymond F, Rasuli P, and Wells PS. Diagnostic value of the electrocardiogram in suspected pulmonary embolism. Am J Cardiol. 2000 Oct 1;86(7):807-9, A10. DOI:10.1016/s0002-9149(00)01090-0 | PubMed ID:11018210 | HubMed [Rodger]
  6. Ferrari E, Imbert A, Chevalier T, Mihoubi A, Morand P, and Baudouy M. The ECG in pulmonary embolism. Predictive value of negative T waves in precordial leads--80 case reports. Chest. 1997 Mar;111(3):537-43. DOI:10.1378/chest.111.3.537 | PubMed ID:9118684 | HubMed [Ferrari]
All Medline abstracts: PubMed | HubMed