Sudden and unexpected deaths from natural causes in Adult

Dr.AmalVadysinghe Department of forensic medicine

University of peradeniya

Objectives

Explain the terminology Discuss the causes of sudden unexpected deaths from natural causes Describe the macroscopic features of each

It has actual or potential medicolegal aspect.

Therefore medicolegal investigation is carried out involving Police, ISD/Magistrate ,Judicial medical officers , witness etc.

To establish cause and manner of death

Legal system has a duty to investigate such death Medical- Identify the fatal disease/and correlate with background information Medico-legal –

-To administration of justice-For any criminality or civil-Workman compensation-Insurance

Unexplained deaths

Patient with an Illness → Investigatedfor a longperiod → Died without a diagnosis→ No time for investigation → Died without diagnosis

Therefore patient might have,-Pre existing chronic disease because of unawareness-Chronic disease → Progress rapidly

→ Trigger to develop fatal sequale/ complication

Trigger maybe trauma-physical/psychological or both.Trauma is directly related to CODEg:- 60-yr-old man with severe ischaemic heart disease,

1. Decapitation by sharp weapon, Directly related to COD, COD – Decapitation2. Blow to the chest - contused precordium - precipitate IHD-Contribute to COD3. Verbal threat/minor trauma.May/May not precipitate the existing disease –COD-?IHD

Evans’ Criteria 1(Evans, A.S. 1976. ―Causation and Disease: The Henle-Koch Postulates Revisited,‖Yale Journal of Biology and Medicine. 49: 175—95.)

•Disease should follow exposure to the putative agent•Exposure increases disease incidence prospectively•Exposure increases disease prevalence•Exposure to the cause more common in those with the disease than those without ceteris paribus•Dose-response relationship

Evans’ Criteria 2 (Evans, A.S. 1976. ―Causation and Disease: The Henle-Koch Postulates Revisited,‖ Yale Journal of Biology and Medicine. 49: 175—95.)

•Experimental reproduction of the disease possible•Measurable host response following exposure to the cause•Elimination of putative cause reduces incidence•Prevention of the host‘s response eliminates the disease•The whole thing should make biologic and epidemiologic sense.

Sudden death(True sudden death)

Instantaneous death (Drops dead) -defined as deathoccuring within seconds of onset of symptoms/infliction of trauma with absolutely no warning.

Non Instantaneous death --death occurring within minutes of the onset of symptoms/ infliction of trauma

The terms sudden and unexpected have different meaning for different people. “Sudden natural death” means different things to different people. Some believe that the term should be limited to those cases in which the time from the onset of symptoms to collapse and death is seconds, whereas others will accept up to 24 hours of symptomatic illness prior to death.

It is generally defined as natural, unexpected death within 1 hour of the onset of symptoms. Four temporal elements should be considered.

prodromes onset of the terminal event cardiac arrest biological death

The 1-hour definition refers to the period between onset of the terminal event, that is, acute changes in cardiovascular status, and cardiac arrest.

In addition, when death occurs unwitnessed within 24 hours of being seen alive and functioning normally, this is also termed SD.

Epidemiology

• The incidence of SD in the general population ages 20 to 75 years is 1 in 1000 individuals, which is 18.5% of all deaths.

• 1- to 40-year age group – incidence is 1.3 to 8.5 per 100 000 person-years.

• The vast majority of cases are considered to be Sudden Cardiac Deaths. • In individuals under 35 years of age, the incidence is highest in the 0- to 5-year age group. • In adults, incidence increases with age in both sexes but is substantially less in women than in men at all ages. • Approximately 80% of SD events take place at home, and around half of them are witnessed.• The incidence of SD in young competitive athletes currently is approximately 0.4 to 0.6 per 100 000 person-

years.

Causes of sudden natural deaths in adults

Cardio vascular disease- Most common. Common cause of death between ages 20- 65years- Common symptoms - Abdominal pain, Indigestion, Heart burn, Neck / Back pain, Nausea

1.Coronary artery disease- 75% of all sudden deaths.- 50% die suddenly.- 25% Die without any preceding history or warning

- Mechanism of death – Cardiac Arrhythmia

Pathological findings- Coronary artery atherosclerosis, +/- CalcificationNarrowed coronaries>=75% (severe) need to cause the death-Thrombosis in coronaries- Myocardium – Scarring/Infarction

2. Hypertensive heart disease (HT)- weight of the heart >350g ( Cardiomegaly)- Thickness of left ventricle > 1.5 cm- May be associated with kidney changes( fine granularity of cortices)

3. Cardiomyopathies

Diseases characterized by myocardial dysfunction of known and unknown aetiologies.( Should exclude Atherosclerosis, HT, Valvular disease, Infections)Types a. Congestive or dilated cardiomyopathies

-Cardiomegally-Dilatation of the several of the heart chambers - Idiopathic dilated cardiomyopathy - Peri/ Postpartum cardiomyaopathy- Chronic / Rheumatic Myocarditis

b. Hypertrophic Cardiomyopathy - Cardiomegally- Not dilated

c. Restrictive/ Infiltrative cardiomyopathy -Cause limitaion of diastolic filling

4. Other coronary artery abnormalitiesa. Coronary artery spasm

- autopsy may show normal coronaries b. Bridging of coronary arteries

-Coronary dips into myocardiumc. Congenital anomalies

- Single coronary artery- Coronary artery Hypoplasia

d. Abnormalities at the site of origin of the coronary ostiae. Acute coronary artery dissection

5. Valvular diseasesa. Floppy mitral valveb. Calcific Aortic stenosis (Common –Bicuspid, Hx of Rheumatic fever,Endocarditis Bacterial/ Viral

6. Myocarditis - Infections, Toxic, Connective tissue disorders7. Diseases of the Aorta - Acute Aortic Dissection (Hypertension, Atherosclerosis, Aneurysm)8.Congenital Heart Disease:

• Congenital aortic or pulmonic valve stenosis.• Right-to-left shunts with Eisenmenger’s physiology:

> Advanced disease.> During labour and delivery.

• After surgical repair of congenital lesionse.g., tetralogy of Fallot.

• CHARGE Syndrome [note the coloboma...abnormal eye pupil shape...plus various cardiac defects]

9.Electrophysiologic Abnormalities:A. Abnormalities of the electrical conducting system:

.Fibrosis of the His-Purkinje system:

.Primary degeneration (Lenegre's disease).

.Secondary to extension of fibrosis .calcification from the mitral valve ring/"cardiac skeleton" (Lev's disease)..Post-viral conducting system fibrosis, Hereditary conducting system disease.

B. Prolonged Q-T interval syndromes [2/3's have history of fainting/syncope] Congenital idiopathic:Acquired:Drug effect.Electrolyte abnormality.Toxic substances.Hypothermia.CNS injury.Idiopathic.

Central nervous system

Occasionally cause sudden death.Less frequent than cardio-vascular diseaseEg.1.Epilepsy

Dies suddenly / Unexpectedly, Usually young, Commonly found dead in bed in themorning +/- FitAutopsy – 25% Bitten tounge. Otherwise almost negative autopsy.Histology, Toxicology, Microbiology all reveal negative results.Mechanism of death may be cardiac arrhythmia. Sometimes epilepsy , following trauma to the head – Post traumatic Epilepsyeg. RTA, Fall , Gunshot, Bomb blast

2.Non traumatic Sub arachnoid haemorrhageEg. a. Ruptured Berry aneurysm of the cerebral vasculature, especially circle of Willis.

b. Intracerebral hemorrhage withextension into the subarachnoid space c. Ruptured Arteriovenous malformationd. Bleeding disordere. Tumours

3. IntracerebralHaemorrhage (ICH)10-30 % of all strokes.Common cause is HT.Other causes: Angiopathy, AV Malformation, Tumors, Bleeding Disorders, Drug induced eg. Cocain, Amphetamines

4. Cerebral infarction/Ischaemic strokeLarge vessel disease – Embolism - ThrombosisSmall vessel disease –Dilatation, Arteriosclerosis – RuptureCommon in HT and DM

Results in,Global Ischaemia- Sudden reduction of cerebral blood flow, Heart attack, Hemorrhagic strokeVenous infarction- Thrombosis of venous system.eg. Polycythemia, Dehydration

5. Brain tumors -Undetected brain tumors – Colloid cyst, Symptoms may be associated with other diseases.e.g. Headache – Migrain- Visual problem, Stroke

Vomiting - Migrain- Visual problem.Stroke, GastritisBehavioral – Psychiatry

6. Meningitis- Purulent meningitis ( bacteria), Viral meningitis

7. Hydrocephalus8. Psychiatric disorderseg. Schizopherenia

Respiratory system

Relatively infrequent.10 % of sudden unexpected deaths.

A. Pulmonary Thromboembolism- Originates at lower extremity.Dislodges and travels to the heart andpulmonary arterial tree. Causes :

a. Stasis of Blood- Immobility : bed rest, Obesity, Intra pelvic tumors, pregnancy, post partum periodb. Venous injury- Trauma to leg – Accidental/ Homicidec. Hypercoagulable states – Dehydration, Oral contraceptive therapy

B. Other forms of pulmonary emboli -Amniotic fluid, Fat, Bone marrow, Air.C. Bronchial Asthma- Acute attackD. Pneumonia- Especially in immunocompromisedEg. HIV , Elderly, DM, MaliganacyE. Acute Epiglotitis- cause mechanical obstruction ofrespiratory passageF. Massive Hemoptysis- Tumors / Inflammatory conditions ofrespiratory passageEg. TuberculosisG. Spontaneous Pneumothorax- Rupture of Bullae

Gastro Intestinal tractVery uncommon.Common causes:

A. Massive Hamatemesis (oesophagealvarices, peptic ulcers)B. Hernias( Inguinal, Umbilical)C. PancreatitisD. Fatty liverE. Diabetes MellitusF. Cirrhosis

Genitourinary systemRuptured tubal pregnancy.

Past Papers

01. A patient who survived an anterior myocardial infarction one year ago died 5 days after a second myocardial infarction. Describe possible macroscopic findings observed in the coronary arteries and the heart at autopsy.

02. The dead body of a 55 year old man was recovered from a river.

2.1 State five (05) possible ways death may have occurred. 2.2 Describe the features you may see, and investigations you would do, at autopsy to determine the

cause of death as drowning.2.3 State five (05) conditions which may have resulted in sudden natural death while in water.

03 3.1 List 3 causes of “Sudden Natural Death” in each system mentioned below.

Cardio Vascular System Respiratory SystemCentral Nervous System

3.2 The cause of death stated by the medical officer at the conclusion of an autopsy was; 1 a. Sub arachnoid haemorrhage

b.Rupture of a berry aneurysm 2. Hypertension State the macroscopic appearances in the following systems that would have assisted the medical officer in arriving at the above cause of death.

A)Central Nervous SystemB)Cardio Vascular System C)Genito Urinary System

04. A previously healthy 70-year-old man living in a retirement home complained of chest pain and died within 12 hours of the complaint. On external examination he was emaciated.

4.1 State five (05) causes of death related to the cardiovascular system that you would suspect in the deceased.

4.2 What autopsy features would suggest that he was chronically starved of food.4.3 Sate five (05) medical conditions that need to be excluded before you suspect

starvation due to negligence.