2. Definition
Unexpectedly
death within 24
hrs from onset of
symptoms with or
without known
preexisting
conditions.
In forensic view
most of cases
occur within
minutes or even
seconds from
onset of
symptoms.
2
3. SUDDEN DEATH
There are no obvious criminal or
accidental causes, and becomes of
some concern to the forensic
pathologist simply because of the
difficulty or even impossibility to
furnish a certifiable cause of death.
The numerous causes of sudden natural
death may conveniently be classified
according to the different anatomical
systems of the body.
3
4. Causes of sudden death
Cardiovascular System
Respiratory System
Gastrointestinal System
Gynecological conditions
Central Nervous System
Other
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5. Heart
• The heart of an adult Indian
– Male 275-300 g
– Female 225-250g
• Thickness
– Atrial wall 1-2 mm
– Right ventricle 3-5 mm
– Left ventricle 10-15 mm
• Layers of the heart
– Outer epicardium
– Middle myocardium
– Inner endocardium
• Heart enclosed by visceral and parietal pericardium
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6. Blood supply
• The Left Coronary Artery: originating from the
left aortic sinus, after a short course, bifurcates
into:
– Left anterior descending which runs in the anterior
inter-ventricular groove, provides blood to anterior
left ventricle, the adjacent anterior right ventricle and
anterior two thirds of the inter-ventricular septum
– Left circumflex branch, which runs in left atrio-
ventricular groove, supplies the lateral wall of the left
ventricle
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7. Blood supply
• The Right Coronary Artery runs in the right
atrio-ventricular groove. It usually nourishes
the remainder of the right ventricle and the
postero-septal region of the left ventricle,
including the posterior third of the inter-
ventricular septum.
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8. The localization of atheroma or
thrombus
• Left anterior descending (left anterior inter-
venrticular) (45-64%)
• Right main coronary (45-46%)
• Left circumflex coronary (3-10%)
• Left main coronary (0-10%)
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9. Type of occlusion
• Simple atheroma
• Ulcerative atheroma
• Sub-intimal hemorrhage
• Coronary thrombosis
• Per arteritis Nodosa
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10. Ischemic Heart Disease
Interruption or
interference with the blood
flow to the heart along the
coronary arteries will have
profound effects on the
heart itself
In the extreme-the heart
will suddenly cease
functioning
In less extreme, areas of
the heart will fail which in
turn causes a chain
reaction and finally the
complete heart failure.
At autopsy, one or more of
the main branches of the
two coronary arteries may
show of severe disease
process.
There will be a deposition
of soft white or yellow
necrotic fatty material on
the lining of the arteries.
11. Ischemic Heart Disease
Myocardial infarction occurs when there is 70%
blockage or more in the lumen of one or more
of the main coronary arteries.
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12. Cardiac temponade
• Cardiac tamponade is caused by a large or
uncontrolled pericardial effusion due to trauma
or after subacute setting after myocardial
infarction (heart attack) which result in pressure
on the heart muscle.
12
13. Hypertensive Heart Disease
An enlargement of the left ventricle of the
heart with accompanying increase in the
thickness of the muscle wall will result in a
raise blood pressure, frequently to a level
twice as high as normal.
So that, rupture of vessels is frequently
seen in the presence of hypertension –
raised blood pressure, example: rupture of
a cerebral artery.
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The cardiac enlargement almost limited to the left ventricle, the three
remaining usually within normal size.
In many cases the cause for cardiac enlargement is unknown, when the
term primary or essential hypertension is used.
14. Hypertensive Heart Disease
• HTN may kill person in a number of ways :
– Cerebral stroke
– Renal failure
– Rupture aneurysm
– Primary HF called “cardiac asthma” or
“paroxysmal nocturnal dyspnea” produced by the
massive pulmonary oedema due to HTN
• Weght of heart >400g
14
15. Aortic Valve disease
Sudden death result because of the
hypertrophied left ventricle to force the
blood through the diseased and
narrowed valve.
An alternative reason is that the disease
process may spread out from the valve
and impede the entry of blood into the
ostia of the nearby coronary arteries.
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16. Hypertrophic obstructive cardiomyopathy
(HOCM)
• Hypertrophic obstructive cardiomyopathy (HOCM) is a
disease that results in abnormal thickening of the
myocardium most commonly in the interventricular
septum
• HOCM can result in clinical heart failure, life-threatening
arrhythmias, mitral regurgitation and sudden cardiac
death.
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17. Sequence of Coronary occlusion
Sudden Death
Myocardial Infarction
Arrhythmia
Left ventricular failure and cardiogenic shock
Rupture of the Myocardium
aneurysms
Myocardial Fibrosis
Mural Thrombosis and Embolism
Pericarditis
Post-myocardial Infarction Syndrome (Dressier Syndrome)
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18. RESPIRATORY SYSTEM
• The main causes are:
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Pulmonary
Embolism
massive
haemorrhage
in the air
passages
pneumothorax
asthma
20. Pulmonary Embolism
Pulmonary embolism (PE) is a blockage of the main artery of
the lung or one of its branches by a substance that has
travelled from elsewhere in the body through the bloodstream
(embolism) especially from deep vein thrombosis (DVT).
Usually results after prolonged immobilization, pregnancy,
obesity, catheterization (endothelial injury).
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21. Haemorrhage in the Air Passages
When a massive haemorrhage occurs
into the major air passages due to
trauma, death results from an
obstruction to normal respiratory
gaseous exchange.
Erosion of a large pulmonary vessel by a
malignant tumor or by an expanding
pulmonary infection (TB).
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22. Pneumothorax
The spontaneous rupture of
an emphysematous bulla on
the periphery of a lung. e.g.:
following a bout of coughing
or straining during some
physical exertion, can be lead
to a massive escape of air
into one of the pleural
cavities.
The vacuum normally
present is lost and
there is an immediate
collapse of the
affected lung.
In the absence of special
medical equipment death
may rapidly ensue,
especially if there is
concomitant disease in
the other lung in the
heart.
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23. Asthma
Asthma is the
sudden and
prolonged spasm
of the smooth
muscles in the
walls of
bronchioles.
The bronchospasm
causes sever
constriction of the
air passages.
In the case, the
death is due to
respiratory failure
in the exchange of
oxygen and carbon
dioxide within the
lungs.
This may due to
obstruction in the
airways, restriction
in the ability to
expand the lungs,
allergic
neuromuscular
problems and
ventilation
abnormalities.
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24. GASTROINTESTINAL SYSTEM
A Massive bleed may
occur when a gastric or
duodenal ulcer erodes
through the sub
mucosal tissues.
The profuse bleeding
may pass down the
intestinal tract emerging
from the anus, or it may
enter the stomach and
be vomited up, or more
frequently it will pass in
both directions.
Another form of
dramatic fatal bleeding
occurs when varicose
and distended veins at
the lower end of the
esophagus become
eroded and burst. This
usually occurs in a
patient who had
developed severe fatty
change or even cirrhosis
of the liver brought
about by chronic alcohol
use.
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25. Gynecological conditions
In pregnancy, sudden deaths are usually
associated with haemorrhage.
25
The rupture of an extra-uterine pregnancy may
produce a massive intra-abdominal hemorrhage
which on occasions has caused death.
Premature separation of a placenta previa may both
cause severe exsanguinations unless there is medical
aid.
Attempts at abortion by inexpert persons may cause
death either by perforation by the instrument of a
major vessel, or by causing pulmonary embolus by
means of air, chemical fluids or the release of
amniotic fluid into the blood stream.
26. CENTRAL NERVOUS SYSTEM
• Nearly always caused by
hemorrhage
which may occur either
within:
– the brain
– the meninges
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27. Cerebral Haemorrhage
This is often referred to as
cerebrovascular accident,
although the word
accident is a misnomer.
The massive bleed
usually occurs
either within the
basal ganglia or
more distally in the
internal capsule.
The
hemorrhage is
associated with
raised blood
pressure
May also occur
in other sites
such as pons or
the cerebellum
but they are
much less
frequently seen.
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28. Circulatory, non-hemorrhagic causes
The formation of a cerebral thrombus in one of the cerebral
arteries at the base of the brain, or within the brain may cause
loss of consciousness leading to death within a short time. The
thrombus is usually formed in association with a localized plaque
of arteriosclerosis.
The most unusual cause is that of a cerebral embolus, which may
arise from an area of thrombus formation within the cavity of the
heart, passing upwards to the brain via one of the carotid arteries.
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30. Epilepsy
Epileptic sufferers may die during a prolonged single
seizure or more usually during a series of repeated
seizures termed status epilepticus
Death is due to asphyxia if the epileptic ceases to
breathe or aspirates regurgitated vomit, or has an
airway obstructed by the tongue.
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31. SUDDEN DEATH FROM UNKNOWN CAUSES
There is nothing more frustrating
than a death for which there is no
demonstrable cause
All cases where after autopsy,
toxicology, bacteriology, virology,
histopathology and a review of the
history of the case with all the
professional concerned, and there is
no reasonable cause to be found.
One very special group of deaths
which still remains a mystery is the
sudden death in infancy syndrome.
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32. sudden death in infancy syndrome
• Incidence rate 1.5-3 per 1000 most common in first 12
months
• Risk factors
– Higher rate incidence in winter
– Death occur in region of Res. Disease
– Male predominance
– More in cities than rural areas
– Mainly between 4-6 months
– Increase incidence in twins, LBW, young mothers
– Poor living conditions
– Bottle-fed babies
– Occur during night
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33. Pathophysiology
• Prolonged sleep apnea
• Cow’s milk coke more than human milk
• Airway obstruction
• Respiratory viruses
• Infants suffering from some occult illness
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