cardiomyopathy

Question 1

what is cardiomyopathy?

Answer 1

structural and functional disorder of ventricular myocardium (heart muscles) not caused by another cardiac disease.

Question 2

name 6 subtypes of cardiomyopathy

Answer 2

hypertrophic
dilated
restrictive
arrhytmogenic right ventricular (ARVC)
takostubo
peripartum

Question 3

what happens in hypertrophic cardiomyopathy (HCM)?

Answer 3

abormal growth of myocardium specifically left ventricle (>15mm) and atrial septum. NOT secondary to diseases which cause LVH eg htn, aortic stenosis

Question 4

what happens in HCOM?

Answer 4

some patients with hypertrophic cardiomyopathy develop left ventricular outflow tract obstruction (LVOTO) due to septum growing assymetrically and obstructing blood flow through aortic valve

Question 5

what are some potential signs of LVOTO?

Answer 5

ejection systolic murmur
can sometimes cause mitral regurgitation

Question 6

what are the genetics behind HCM?

Answer 6

60% of cases are due to a single autosomal dominant inherited mutation.
some can be spontaneous non inherited mutations

Question 7

if someone has a strong family history of HCM/sudden cardiac death but no genetic causes were found in genetic tests what needs to happen?

Answer 7

family members have regular cardiac screening with ECGs and echos

Question 8

what happens in dilated cardiomyopathy?

Answer 8

dilated and thin walls, less contractility

Question 9

what is the most common consequence of dilated cardiomyopathy?

Answer 9

heart failure

Question 10

what are the causes of dilated cardiomyopathy?

Answer 10

usually idiopathic
can be caused by single gene mutations, usually autosomal dominant genetic inheritance

Question 11

what are the risk factors for dilated cardiomyopathy?

Answer 11

FH
alcohol
chemotherapy
viral myocarditis
autoimmune disease
pregnancy

Question 12

what happens in restrictive cardiomyopathy?

Answer 12

stiff ventricle walls leading to less ventricular filling. atria can also become enlarged as a result of this extra pressure.

Question 13

what are the causes of restrictive cardiomyopathy?

Answer 13

usually due to systemic disease which leads to abnormal protein infiltration or scarring of ventricle walls eg amyloidosis, sarcoidosis, haemachromatosis

Question 14

what happens in arrhythmogenic right ventricular cardiomyopathy (ARVC)?

Answer 14

replacement of normal myocardium with fibro-fatty tissue. abnormal tissue is high risk of conducting electrical signals poorly and patients are at risk of developing life threatening arrhythmias.

Question 15

what can you do in ARVC to reduce the number of VTs?

Answer 15

radio-ablation -use heat on area of heart causing abnormal rhythm to break abnormal circuits and destroy areas of heart muscle which are triggering arrythmias

Question 16

what are the differences between primary and secondary cardiomyopathies?

Answer 16

primary =primary disease of heart muscle itself eg HCM, myocarditis
secondary=develops due to secondary condition eg amyloidosis, sarcoidosis, haemachromatosis , fabry’s disease

Question 17

what is fabry’s disease?

Answer 17

genetic disorder that means you don’t have an enzyme to break down some lipids so some lipids build up in different organs in the body.

Question 18

what are the red flags for cardiomyopathy?

Answer 18

sx of poor cardiac output esp exercise induced: dyspnoea, angina, syncope, lightheadedness
palpitations
FH of sudden cardiac death, unexplained wierd heart things

Question 19

what are some signs of cardiomyopathy?

Answer 19

forceful apex beat -in hypertrophic
S4 heart sound (atrial gallop) -caused by atria contracting forcefully to try and pump blood into thickened ventricles-found in hypertrophic and restrictive.
double impulse
ESif HOCM -made worse by valsalva manouvre which increases preload

Question 20

what can be found on an ECG in HCM?

Answer 20

evidence of LVH
deep narrow Q waves

Question 21

what is the best initial imaging test for cardiomypathy?

Answer 21

echo

Question 22

what are some beyond tests that may be needed for cardiomyopathy?

Answer 22

ambulatory ECG
exercise stress testing
cardiac MRI
genetic testing
ventricular biopsy

Question 23

what can you assess with ambulatory ECG?

Answer 23

arrhythmias

Question 24

when would you do genetic testing in someone with cardiomyopathy?

Answer 24

someone with HCM and a strong FH of HCM (>1 relative with known disease) or FH of severe disease (unexplained sudden cardiac death)

Question 25

when would you do a ventricular biopsy in cardiomyopathy?

Answer 25

patients with restrictive CM might rarely need one to see what’s been causing the restrictions.

Question 26

what is the leading cause of death in young people and how does it happen?

Answer 26

HCM
usually occurs during exertion and has been noted in extreme athletes
most common noted cause =VF

Question 27

what advice are young people with HCM given?

Answer 27

avoid competitive sports
avoid becoming dehydrated

Question 28

what are the complicatiosns of cardiomyopathy?

Answer 28

sudden death
heart failure
arrhythmias and AF
clots

Question 29

why does cardiomyopathy lead to arrhythmias and which types?

Answer 29

abnormal heart structure leads to issues with electrical conduction
AF-1/5 of HCM patients!
non sustained VT
VF

Question 30

how can you manage arrhythmias caused by cardiomyopathies?

Answer 30

consider anticoag for AF
consider ICDs
consider beta blockers and verapamil

Question 31

why does cardiomyopathy cause clots?

Answer 31

abnormal movement of the heart