Cardiac Pathology

Question 1

What is the adverse effect of taking verapamil and a beta blocker together?

Answer 1

Dangerous bradycardia

Question 2

What is hypertrophic cardiomyopathy?

Answer 2

Variable hypertrophy in distribution and extent of LV/both ventricles

Question 3

What are the morphological features of hypertrophic cardiomyopathy?

Answer 3

Myocyte hypertrophy and disarray
Interstitial fibrosis
Thickened intima of small intramyocardial arteries

Question 4

What are the different pathophysiologies of hypertrophic cardiomyopathy?

Answer 4

Impaired ventricular compliance > diastolic failure
Impaired LV outflow
Ischaemia from increased muscle mass and abnormal intramyocardial arteries +/- increased wall stress related to outflow obstruction

Question 5

What is the clinical picture of hypertrophic cardiomyopathy?

Answer 5

Asymptomatic
Due to ischaemia +/- increased wall stress
- Arrhythmias
- Angina
- Heart failure
Due to abnormal myofibres
- Arrhythmias

Question 6

When does hypertrophic cardiomyopathy usually present?

Answer 6

Before 4th decade

Question 7

What is the aetiology of hypertrophic cardiomyopathy?

Answer 7

Genetic

• Autosomal dominant
• Mutations in genes encoding sarcomeric proteins

Question 8

Where do watershed infarcts occur?

Answer 8

Borders between cerebral vascular territories > little-no anastamoses

Question 9

What are the two different types of acute tubular necrosis?

Answer 9

Ischaemic

Nephrotoxic

Question 10

What pathology happens in shock to the major organs?

Answer 10

Acute myocardial ischaemia > subendocardial necrosis
Kidney - acute tubular necrosis
Liver - centrilobular necrosis
Acute respiratory distress syndrome/diffuse alveolar damage

Question 11

What is the most common type of cardiomyopathy?

Answer 11

Idiopathic dilated cardiomyopathy

Question 12

What does idiopathic dilated cardiomyopathy do?

Answer 12

Dilation and impaired contraction of LV/both ventricles

Often also affects atria

Question 13

What is the morphology of idiopathic dilated cardiomyopathy?

Answer 13

Eccentric hypertrophy of LV +/- RV
Myocyte hypertrophy
Interstitial and endocardial fibrosis

Question 14

When does idiopathic dilated cardiomyopathy often become apparent?

Answer 14

3rd-4th decade of life

Question 15

What are the clinical features of idiopathic dilated cardiomyopathy?

Answer 15

Deteriorating biventricular failure
Arrhythmias
- Sudden death
Thromboembolic complications
Steady course +/- improvement

Question 16

What is the aetiology of idiopathic dilated cardiomyopathy?

Answer 16

Genetic
Possible factors
- Viral
- Toxic
- Autoimmune

Question 17

What are some conditions in which dilated cardiomyopathy can occur?

Answer 17

Peripartum period
Haemochromatosis
Alcohol
Certain drugs
Ischaemia
Some neuromusuclar diseases; eg: Duchenne's muscular dystrophy

Question 18

What is restrictive cardiomyopathy?

Answer 18

Rigid but not necessarily thickened ventricles

Impaired diastolic filling > failure

Question 19

What is restrictive cardiomyopathy related to?

Answer 19

Fibrosis of endomyocardium

Infiltration of myocardium; eg: amyloid in primary/secondary/senile amyloidosis

Question 20

What is arrhythmogenic right ventricular cardiomyopathy?

Answer 20

Replacement of cardiomyocytes by fibro-fatty tissue
Serious arrhythmias
Sudden death

Question 21

What is the aetiology of arrhythmogenic right ventricular cardiomyopathy?

Answer 21

Autosomal dominant

Variable penetrance

Question 22

What is myocarditis?

Answer 22

Inflammation and necrosis/degeneration of myocytes

Question 23

What are the causes of myocarditis?

Answer 23

Infection
Sarcoidosis
Giant cell myocarditis
Acute rheumatic fever
Toxic 
Drugs
Transplant rejection

Question 24

What viruses can cause myocarditis?

Answer 24

Coxsackie

Echoviruses

Question 25

What protozoans can cause myocarditis?

Answer 25

Chaga's disease | Toxoplasma

Question 26

What causes toxic myocarditis?

Answer 26

Diphtheria

Question 27

How can drugs cause myocarditis?

Answer 27

Hypersensitivity | Cardiotoxic

Question 28

What is the most common type of myocarditis?

Answer 28

Viral

Question 29

What is the microscopic appearance of viral myocarditis?

Answer 29

Patchy mononuclear infiltrate | Myocardial necrosis

Question 30

What is the macroscopic appearance of viral myocarditis?

Answer 30

Mottled/dilated/normal

Question 31

What are the clinical features of viral myocarditis?

Answer 31

``` Asymptomatic Flu-like illness Chest pain Syncope Rapid onset heart failure Arrhythmias Sudden death ```

Question 32

What are the outcomes of viral myocarditis?

Answer 32

Resolution Rapid deterioration Slow progression to dilated cardiomyopathy

Question 33

What are the complications of cardiac sarcoid?

Answer 33

Arrhythmias Heart failure Sudden death

Question 34

What is sudden death?

Answer 34

Unexpected fatal event within 1 hour of beginning of symptoms/without symptoms in apparently healthy subject/not severe disease

Question 35

What is the pathophysiology of ventricular tachyarrhythmias?

Answer 35

Automaticity of diseased ventricular myocytes Wave propagation of ventricular impulse interrupted by diseased muscle > intraventricular re-entry Abnormalities of repolarisation

Question 36

What are some causes of sudden cardiac death in young people due to coronary artery disease?

Answer 36

``` Congenital coronary artery anomalies Vasculitis Coronary emboli Spontaneous dissection Atherosclerosis ```

Question 37

What are some causes of sudden cardiac death in young people due to the myocardium?

Answer 37

``` Hypertrophic cardiomyopathy Dilated cardiomyopathy Arrhythmogenic cardiomyopathy Myocarditis LVH of >50% by mass ```

Question 38

What are some causes of sudden cardiac death in young people due to morphological conduction pathways?

Answer 38

Wolf-Parkinson-White disease Sarcoidosis Autoimmune associated inflammation; eg: ankylosing spondylitis

Question 39

What are some causes of sudden cardiac death in young people due to valves?

Answer 39

Congenital aortic stenosis > LVH | Floppy/myxomatous mitral valve

Question 40

What are some causes of sudden cardiac death in young people that are acquired?

Answer 40

``` Thiuzides Macrolides Methodone Halperidol Selective reuptake inhibitors Antihistamines Hypothyroidism Hypocalcaemia Cocaine ```

Question 41

What can cause an aortic rupture?

Answer 41

Dissection | Infection

Question 42

How can aortic dissection cause death?

Answer 42

Haemopericardium > tamponade Coronary artery narrowing > myocardial ischaemia/infarction Rupture > hypovolaemia Acute aortic valve incompetence