Sudden deaths due to natural diseases-2.pptx

1. Chapter 8 Sudden deaths due to natural
diseases-2
Forensic medicine department of nanchang university
Yanhong,Li
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2. Common Causes of Sudden Unexpected Deaths by
Organ System
Cardiovascular system diseases
Central nervous system diseases
Respiratory system diseases
Gastrointestinal system diseases
Endocrine system diseases
Other diseases
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3. Cardiovascular system diseases
● Coronary atherosclerotic heart disease
● Hypertensive Cardiovascular
● Valvular Disease
● Myocarditis
● Cardiomyopathy
● Aortic Aneurysm and dissection
● Pulmonary Thromboembolism
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4. 1.1 Atherosclerotic Cardiovasular disease
Coronary atherosclerosis is the most common
cause of sudden cardiac death(SCD).
It is accepted that around 70% of SCD is due to
coronary atherosclerosis in adults.
The incidence of all SCD increases with
age,largely due to an increased in incidence of
coronary atherosclerosis and acquired
cardiomyopathy.
Coronary atherosclerotic heart disese
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5. Right coronary:
①posterior wall of left ventricle;
②1/3ventricular septa;
③2/3anterior wall of right
ventricle(R));
④ posterior wall of right ventricle
Left anterior descending:
①apex cordis;
②the most of
ventricular anterior wall;
③ 2/3ventricular septa;
④ 1/3anterior wall of
right ventricle(L)
Left circumflex:
left ventricle lateral wall
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6. 6
Normal coronary artery
Coronary Atherosclerosis
Normal coronary Coronary Atherosclerosis
Cholesterol
crystallization
intra-plaque
hemorrhage
Stenosis of
coronary
Calcium salt

7. • I degree < 25%
• II degree26%-50%
• III degree51%-75%
• IV degree>76%
The degree of narrowing
Left anterior descending > Right coronary > Left circumflex or
left main coronary
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8. •The mechanism of sudden coronary death is usually a
ventricular tachyarrhythmia. The substrate for the arrhythmia is a
focus of presumed ischemia if there is an acute coronary
thrombus. Because ischemia is not histologic evident for 24 or
more hours, in most cases of SCD due to coronary artery disease
the myocardium does not show evidence of acute ischemia
change.
In up to 50% of cases of coronary SCD, there is no acute
thrombus. In these cases the cause may be due to presence of
remote infarct or scar,or concomitant cardiomegaly.
If plaque reputure, plaque erosion complicated by
thrombosis,hemorrhage in plaque, massive myocardial infarction
or heart rupture are detected in coronary artery, they are often
regarded as strong evidence of sudden death of coronary heart
disease. 8

9. Myocardial infarction,Myocardial fibrosis
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10. Cardiac rupture
Acute cardiac tamponade
Sudden death
Ventricular aneurysm
pericardium 10
Myocardial infarction

11. Left circumflex coronary artery atherosclerosis(4 degree）
Hemorrhage in plaque

12. Case
In September 16, 2004，Mr zhang was found dead at
home,lying in the bed. In order to know the cause of death .The
autopsy was performed.
Autopsy results：Nothing abnormal was observed in the external
examination. Pericardial cavity was filled with massive
hemorrhage and blood clots, about 500 ml.There was a gray,
gray- red area as a map of irregular shape with a 3cm long split in
it.Yellow-white plaques were found in the beginning of the left
anterior descending coronary and left circumflex . Yellow-white
plaques were found in the right coronary artery.
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13. 13

14. Histological changes:Multifocal myocardial necrosis with
neutrophil infiltration around the necrotic area.Cell shape is
visible, nucleus disappears, cytoplasm stained red. Some
necrosis areas were surrounded by inflammatory granuloma .
There was inflammatory cells infiltration in epicardium.
Coronary atherosclerotic plaques were composed by a fibrous
“cap” and foam cell , necrotic materials and cholesterol
crystals,with luminal narrowing.
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15. 2. Myocarditis
• Inflammatory myocardial disease as a cause of death is most
frequently seen in infants and children as lymphocytic
myocarditis, but occurs in adults as well.
• Usually a sequela of viral infection,lymphocytic myocarditis is
the cause of sudden cardiac death in 15-20% of sudden deaths
in children and young adolescent,and about 5% in young adult.
At autopsy, a pericardial effusion is often found. Histologically,
there is myocyte necrosis and an extensive lymphocytic
infiltrate.
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16. A woman, aged 48.
A man, aged 28.
A boy, aged 6.
The degree of infiltration may be especially marked in fants and young children,and
there may be scattered neutrophils and histiocytes,in addition to lymphocytes.
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17. • Mechanisms of sudden deaths caused by myocarditis：
①heart failure
②dysfunction of cardiac conduction system
• Forensic examination
Must find obvious myocarditis histologic change.Blood and
extract the diseased tissue can be tested for the virus or to
determine the virus and its type.
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18. 3.Aortic dissecting aneurysm
3.1Aortic dissecting aneurysm is a
serious life-threatening medical
emergency. It can be classified into:
Type I：dissections with intimal tears in the ascending
aorta frequently extend distal to the arch as far as the
iliac bifurcation；
Type II： dissections with intimal tears in the ascending
aorta and limited to itself ；
Type III：the intimal tear in aortic arch,the descending
aorta,extend to abdominal aorta ,the ascending aorta is
not involved.
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19. 3.2The risk factors for aortic dissection
⑴congenital disease:Marfan syndrome,bicuspid aortic
valve, hypertension.
⑵Blunt chest trauma and others(cocaine and
methamphetamine use, Turner syndrome, Ehlers
Danlos syndrome, polycystic kidney disease)
Aortic dissection formation must have two basic
elements: Artery media degeneration and high blood
pressure in the arteries.
Risk factor assessment is important at forensic
autopsy, and counseling of family members has been
recommended in potential heritable causes.
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20. 3.3 Aortic aneurysm and dissection examination
On external forensic evaluation: no sign.
Internally:
most cases show hemopericardium.
Occassionally,A type Ⅲ dissection will cause sudden death
by rupture into the left pleural cavity and hemothorax.
Rarelly,sudden death may occur in’bloodless’dissection,in
which an intimal tear is present,and a clear dissection plane at
autopsy,with spontaneous separation of the media from the
adventitia.
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pericardial tamponade The adventitia tear The intimal tear

21. Hemothorax on the left
External tear in the arch Intimal tear in the arch
A woman, aged 50
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case

22. 4. Pulmonary thromboembolism
•In approximately 25% of patients, the first
mainfestation of pulmonary embolism is sudden-
unexpected death,and at forensic autopsy,pulmonary
embolism represents about 4% of sudden deaths.
•The risk factors for pulmonary embolism are deep
venous thrombosis, trauma, post-operative state,
obesity, malignancy, old age, female gender, and
chronic heart disease.
•At forsensic autopsy, almost three-quarters of patients
are obese, and a high percentage of patients were
evaluated for symptoms with the diagnosis missed or
overlooked.
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23. 4.1 the status of sudden death induced by pulmonary embolism
⑴Pulmonary embolism is considered a cause of death when
extensive,or when there are co-morbid conditions with
peripheral emboli without other causes of death.
⑵Emboli present in the main pulmonary trunk or in the
proximal right or left pulmonary arteries are considered a
cause of death.
⑶Distal emboli may be considered a cause of death if there are
underlying conditions that contributed to death but are no
considered a definitive cause of death.
⑷Massive pulmonary embolism denotes obstruction of either
of the main pulmonary ateries or more than two lobar
arteries and is considered invariably fatal.
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24. 4.2The mechanism of sudden death of pulmonary
embolism?
⑴mechanical obstruction:That larger emboli blocking
pulmonary artery trunk or branches, leads to acute right
heart failure; That pulmonary artery blood flow suddenly
is suspended suddenly, then the left ventricle reflux
decreases and left heart coronary perfusion becomes
inadequacy. In the end cardiac shock occurs.
⑵Nerve reflection factor :The vagus nerve reflex causes
pulmonary artery, coronary artery spasm and
bronchospasm. Embolus can also release a large number
of cytokines that caused vasospasm, which aggravates
heart failure, suffocation, etc.
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25. Grossly,a recent
thromboembolus is usually
cylindrical and takes the
form of the containing
vessel and not the
pulmonary atery.The ends of
emboli that are removed at
autopsy are blunt and the
surface is smooth.Unlike
post-mortem thrombi,they
protrude from the surface of
the cut lung and are
impacted in the distended
artery.
4.3 Pathological Change
Pulmonary thromboembolus
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thromboembolus

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