4. Sudden death from natural causes Flashcards
In the heart (3)
- ischemic heart disease
- valvular heart disease
- cardiomyopathies etc.
Explain ischemic heart disease
- insufficiency of blood supply to myocardium
- 1st case: restricted supply due to narrowed vessels
-2nd case: increased demand due to increased muscle - all arteries develop atheroma over time, resulting in narrowing of the lumen
- this is particularly significant in the coronary arteries
Atheroma risk factors (7)
- genetic
- diet
- smoking
- obesity
- lack of exercise
- high blood pressure
- diabetes
2 main effects of moderate/severe atheroma
- angina
- sudden death
Angina characteristics (6)
- can develop into unstable angina
- pain at rest
- ECG changes
- increase in troponins
- due to disrupted plaque
- treated with stents and bypass
Sudden death from atheroma characteristics (3)
- commonest cause of sudden death in western world
- due to chronic electrical heart instability and development of sudden fatal arrhythmia
- can develop at any time, but may be precipitated by physical exertion or stress
What does coronary artery thrombosis lead to? (4)
- thrombus forms on the top of the atheroma
- completely blocks the lumen
- this leads to acute myocardial infarct
- death of myocardium supplied by that particular coronary artery
Acute complications of acute myocardial infarction (4)
- arrhythmias
- cardiogenic shock
- papillary muscle rupture
- cardiac rupture
Long term complications of acute myocardial infarction (3)
- chronic heart failure
- arrhythmia
- angina
Causes of cardiac enlargement (3)
Due to factors not to do with myocardium:
- hypertension (hypertrophy of left ventricle)
- aortic stenosis (calcification of bicuspid valve or due to bacterial endocarditis)
Due to primary abnormality of myocardium:
- cardiomyopathy: hypertrophy obstructive cardiomyopathy or dilated cardiomyopathy
Sudden arrhythmic/adult death syndrome (SADS) (2)
- channelopathies:
- long QT syndrome
- Brugada syndrome
Aortic aneurysm death
- arterial CVD cause
- ruptured aortic aneurysm
- aneurysms are result of severe atheroma
- in this cause effect of atheroma is primarily weakening of the wall rather than narrowing
- can eventually rupture and usually seen in older people
Embolism characteristics
- venous CVD cause
- emboli can be: thrombus, fat/bone marrow, air, amniotic fluid, blood clot
- thrombi are formed in leg veins (travel to lungs) or in the heart (travel to brain)
Pulmonary embolism
- starts with DVT
- blood clot forms in the leg veins (deep calf, ilio-femoral or pelvic)
- thrombus breaks off and embolises
- goes to pulmonary arteries
Risk factors for DVT/PE
- recent surgery
- immobility
- obesity
- age
- CHF
- varicose veins
- malignancy
- pregnancy
- certain oral contraceptives
- inherited blood disorders
- long air jurneys
Causes of sudden death in the lungs (2)
- pneumonia
- asthma
Pneumonia types and characteristics (2)
- Lobar pneumonia
- largely in one lobe
- firm and grey
- infection via blood
- usually in debilitated individuals
- Bronchopneumonia
- more general, often both lungs
- more patchy
- often a complication of something else (chronic lung disease, head injury, trauma etc.)
Acute asthma death
- hypersensitivity response
- medium and small bronchi blocked by combination of plugs of mucous and spasms
- lungs become hyper-ventilated
- acute breathlessness and stridor
Sudden death in the abdomen (3)
- GIT haemorrhage (ulcers, varices)
- Peritonitis (perforated ulcers, perforated large bowel diverticula, perforation in intestinal obstruction)
- Bowel infarction (strangulated herniation, vascular disease)
Sudden death in the brain (4)
- cerebral haemorrhage
- subarachnoid haemorrhage
- epilepsy
- meningitis
Cerebral haemorrhage (4)
- basal ganglia or brainstem usually
- hypertension
- older people
- fairly rapid unconsciousness and often fatal
Subarachnoid hemorrhage (4)
- base of brain around brainstem
- due to rupture of small aneurysm (berry aneurysm) from congenital weakness of the wall
- can occur at all ages
- not always fatal, surgery
Meningits (5)
Meningococcal
- inhaling droplets
- often in previously healthy
- often rapid course of illness (less than a day)
Pneumococcal
- usually from lung infection
- more common in debilitated
Epilepsy
- due to abnormal discharge of neurons
- death can occur during grand mal seizure
- most deaths are from SUDEP (sudden unexpected death in epilepsy)
- probably due to cardiac arrhythmia or apnoea
Rapid death (3)
- coronary artery disease
- cardiac enlargement
- pulmonary thromboembolism
Less rapid death (6)
- acute MI
- ruptured aortic aneurysm
- cerebral haemorrhage
- acute asthma
- epilepsy
- GIT haemorrhage
