Cardiomyopathies

Question 1

What is cardiomyopathy

Answer 1

disease of heart muscle making it difficult for heart to pump to the rest of the body. Can lead to heart failure

Question 2

Types of cardiomyopathy

Answer 2

Dilated
Hypertrophic
Restrictive

Question 3

What is dilated cardiomyopathy? (DCM)

Answer 3

Ventricular chamber enlargement (>4cm) and systolic dysfunction

Question 4

Primary causes of dilated cardiomyopathy

Answer 4

Genetics
Idiopathic (w/o FH)

Question 5

What are some secondary causes of dilated cardiomyopathy?

Answer 5

MI, Heart valve disease, thyroid disease, myocarditis, alcoholism, autoimmune

Question 6

Pathophysiology of dilated cardiomyopathy

Answer 6

Damage/death of myocytes (inflamm/toxic)
Eccentric fibrosis + vol ^
LV enlargement w/o ^ muscle mass due to fibrosis of the muscles
initially contractility is ok (frank-starling law)
Gradual over distension and systolic dysfunction
red. CO + ^EDV/EDP
Vol overload and congestive heart failure

Question 7

Why does DCM lead to dyspnoea and cold, clammy extremities

Answer 7

red CO -> insufficient tissue O2

Question 8

Why is there a displaced apex beat in DCM

Answer 8

Enlarged left ventricle

Question 9

Why would a px with DCM experience fatigue

Answer 9

red CO/organ perfusion

Question 10

What causes angina in cardiomyopathy

Answer 10

low coronary perfusion

Question 11

What is a sign of pulmonary congestion

Answer 11

diffuse crackles

Question 12

What can heart failure lead to

Answer 12

Pulmonary oedema

Question 13

What is the presentation of dilated cardiomyopathy?

Answer 13

Dyspnoea, displaced apex beat, fatigue, angina, pulmonary congestion, low cardiac output

Question 14

Investigations for the diagnosis of dilated cardiomyopathy

Answer 14

ECG
CXR
cardiac MRI/CT
Cardiac catheterisation
Echocardiography

Question 15

What investigations would you carry out if you suspected familial/viral cause of dilated cardiomyopathy

Answer 15

Genetic testing
viral serology

Question 16

What are the main types of management in dilated cardiomyopathy

Answer 16

counselling - irreversible
Alleviate the cause
Symptom relief

Question 17

What are the general areas of treatment for dilated cardiomyopathy?

Answer 17

Diet (fluid and Na+ restriction),
treat underlying conditions (immunosuppressants),
heart failure symptoms (ACE-i, beta blockers),
treat arrhythmias (atrial fibrillation),
thromboembolic events (anticoag)

Question 18

What is hypertrophic cardiomyopathy? (HCM)

Answer 18

Genetic CVD
^ LV wall thickness / interventricular septum thickness -> obstruction of flow through left ventricle

Question 19

Why does hypertrophic cardiomyopathy cause sudden death?

Answer 19

Often asymptomatic, first clinical presentation is ventricular fibrillation

Question 20

Pathophysiology of HCM

Answer 20

Genetic disease/disorders -> thickened LV myocardium/septum -> obstruction of flow
Disorganised myocytes disrupt signal conduction
Ventricular arrhythmia
Sudden cardiac death

Question 21

How does HCM present?

Answer 21

Sudden cardiac death, syncope, congestive heart failure, S4 sound, angina, ejection systolic murmur

Question 22

Why is there an S4 sound in HCM

Answer 22

Forceful atrial contraction into hypertrophic LV

Question 23

What causes syncope in HCM

Answer 23

red. CO to peripheries and head

Question 24

Why does a px with HCM feel fatigue

Answer 24

low CO and red. organ perfusion

Question 25

Why is a systolic murmur heard in HCM

Answer 25

Impaired passage of blood through to aorta

Question 26

Investigations to diagnose HCM

Answer 26

Echocardiogram CXR Cardiac MRI

Question 27

How would you manage HCM initially?

Answer 27

Beta blocker, verapamil if contraindicated

Question 28

What is the more severe management of HCM?

Answer 28

Mechanical therapy - pacemaker, septal myectomy or ablation (remove part of septum)

Question 29

What is restrictive cardiomyopathy? RCM

Answer 29

Rigid heart muscles restricts heart stretch/ventricular filling

Question 30

Describe the pathophysiology of restrictive cardiomyopathy

Answer 30

Deposition of abnormal substances (amyloids proteins, noncaseating granulomas) in heart tissue, Infiltrates ventricular walls ->fibrosis/stiffening -> diastolic dysfunction. Atrial enlargement in response conductive abnormalities -> diastolic heart failureW

Question 31

What can advanced restrictive cardiomyopathy lead to

Answer 31

Adverse remodelling -> systolic dysfunction/ ventricular arrhythmias

Question 32

What causes ascites and peripheral pitting oedema in RCM

Answer 32

^ venous pressure -> right sided heart failure (back pressure into systemic veins)

Question 33

Why is there hepatomegaly in RCM

Answer 33

Hepatic congestion due to RHF

Question 34

Why is S4 heard in RCM

Answer 34

atrium contracts to pump blood into stiff ventricle

Question 35

Why is there an increase in JVP in RCM

Answer 35

RHF means greater pressure in the veins

Question 36

What is the presentation of restrictive cardiomyopathy?

Answer 36

congestion (fluid in abdomen and lungs), hepatomegaly, increased jugular venous pressure, reduced Pulse/SV/CO

Question 37

Investigations for the diagnosis of RCM

Answer 37

Serology Amyloidosis check CXR ECG Echocardiography MRI

Question 38

What are the 5 management techniques for restrictive cardiomyopathy?

Answer 38

Heart failure meds, antiarrhythmic therapy, immunosuppression (steroids), pacemaker, cardiac transplantation