Cardiomyopathy, hypertrophic, dilated, restrictive and myocarditis

Question 1

What is dilated cardiomyopathy?

Answer 1

Is in effect a structural and functional description, the leftventricular function is impaired
Can be a primary problem or the end result of almost any pathological insult to the myocardium

Question 2

Aetiology of cardiomyopathy?

Answer 2

Genetic and familial DCM: SCN5A gene, muscular dystrophy
Inflammatory, infectious, autoimmune, postpartum
Toxic; drugs, exogenous chemicals, endocrine
Injury, cell loss, scar replacement

Question 3

What chambers can be affected in dilated myopathy?

Answer 3

Can be one but more often all chambers dilated and functionally impaired . Thrombosis in chambers is not uncommon.

Question 4

symptoms of dilated myocardopathy?

Answer 4

Progressive, slow onset, dyspnoea, fatigue, orthopnoea, PND, ankle swelling, weight gain of fluid overload, cough.

PMHx; systemic illness, travel, HT, vascular disease, thyroid, neuromuscular disease
FH ?
SH alcohol, job

Question 5

Examination of dilated myopathy?

Answer 5

Poor superficial perfusion, thready pulse, irreg if in AF, SOB at rest, narrow pulse pressure, JVP elevated+/- TR waves, displaced apex, S3 and S4, MR murmur often, pulmonary oedema, pleural effusions, ankle oedema, sacral oedema, acites, hepatomegally

Question 6

Investigations for dilated cardiomyopathy?

Answer 6

Repeated ECG noting LBBB if present
CXR
N termial pro Brain Natriuetic Peptide
Basic bloods FBC, U+E
Echo
CMRI, probably best imaging modality
Coronary angiogram
Sometimes biopsy depending on time course of cardiomyopathy

Question 7

What are the general measures in treatment of cardiomyopathy?

Answer 7

Correct anaemia
Remove exacerbating drugs eg NSAIDs
Correct any endocrine disturbance
Advise on fluid and salt intake, reduce it
Advise on managing weight to identify fluid overload
HF nurse referral

More specific measures
ACEI, ATII blockers, diuretics, Sac/Val
Beta blockers
Spironolactone
Anticoagulants as required
SCD risk assessment with ICD or CRT-D/P implant
Cardiac transplant
Often the cause is not one of the reversible ones so little in the way of truly focused therapy

Question 8

What is restrictive and infiltrative cardiomyopathy?

Answer 8

Less common, again describes the physiology of filling and myocyte relaxation capacity, the systolic function may or not be impaired
The pathology surrounds the inability to fill well a ventricle whose wall has reduced compliance.
Relaxation of the ventricular wall is an active process that needs functioning intact myocytes, it is not passive.
Note below the gross bi atrial dilation

Question 9

Causes?

Answer 9

Non infiltrative; Familial, forms of HCM, Scleroderma, diabetic, pseudoxanthoma elasticum
Infiltrative; Amyloid, Sarcoid
Storage diseases; Haemachromatosis, Fabry disease
Endomyocardial; Fibrosis, carcinoid, radiation, drug effects

Question 10

Investigations for restrictive and infiltrative cardiomyopathy?

Answer 10

Repeated ECG noting LBBB if present and other conduction defects
CXR
N termial pro Brain Natriuetic Peptide
Basic bloods FBC, U+E, be on the look out for sarcoid and haemachromatosis
Auto antibodies for sclerotic CT diseases
Amyloid needs non cardiac biopsy to help establish the diagnosis
Fabry; low plasma alpha galactosidase A activity
Echo
CMRI, probably best imaging modality
Biopsy more helpful but still has high false negative rate

Question 11

Treatment for restrictive and infiltrative cardiomyopathy?

Answer 11

General measures
More specific measures
Limited diuretic use as low filling pressures will cause problems
Beta blockers limited ACEI use
Anticoagulants as required
SCD risk assessment with ICD or CRT-D/P implant but limited evidence
Cardiac transplant
If iron overlaod, specific forms of amyloid or Fabrys then specific treatments are available
Endomyocardial fibrosis has little specific treatment

Question 12

What is hypertrophic myocardopathy?

Answer 12

Again impaired relaxation is a common feature and systolic function is usually adequate albeit with some functional abnormality

Question 13

Prevalence of hypertrophic cardiomyopathy?

Answer 13

Relatively high prevalence 1:500
Genetic basis over 1500 genes now identified
Sarcomere gene defect. Autosomal dominant, but !!
Variable expression and incomplete penetrance
50% chance of inheriting the gene but how it is expressed is not known until time passes

Question 14

Pathology of hypertrophic cardiomyopathy?

Answer 14

Myocyte hypertrophy and disarray
Can be generalised or segmental wall thickness >14mm or >12mm in primary relative
Can be apical, septal or generalised
Impaired relaxation so behaves in a restrictive manner
If septal hypertrophy this can with mitral valve defect lead to LVOT obstruction

Question 15

Symptoms of hypertrophic cardiomyopathy?

Answer 15

Symptoms
Breathless, palpitations, syncope, exertional symptoms, SCD
Asymptomatic for many, fatigue, dyspnoea, anginal like chest pain, exertional pre syncope, syncope related to arrhythmias or LVOT obstruction
FH ?
Examination findings
Can be none !
Notched pulse pattern
Irreg pulse if in AF or ectopy
Double impulse over apex, thrills and murmurs, often dynamic, LVOT murmur will increase with valsalve and decrease with squatting
JVP can be raised in very restrictive filling

Question 16

Hyper trophic cardiomyopathy assessment?

Answer 16

ECG, often abnormal but a few are normal where phenotype is poorly expressed in genotype +ve individuals
Echo
CMRI
Risk stratification for SCD, may need ICD
Holters repeatedly, ETT, FH ?

Question 17

General measures for hypertrophic cardiomyopathy?

Answer 17

Avoid heavy exercise
Avoid dehydration
Explore FH and first degree relatives, ECGs and echoes may be required
Consider genetic testing
Regular FU to re appraise the risks and progress
Specific measures
Drugs to try and enhance relaxation, variable results but often if symptomatic, beta blockers, verapamil, disopyrimide
If in AF anticoagulate
Obstructive form; surgical or alcohol septal ablation
ICD if required based on risk stratification

Question 18

What is myocarditis?

Answer 18

Acute or chronic inflammation of the myocardium
Can be in association with pericarditis
Can impair myocardial function, conduction and generate arrhythmia

Question 19

Pathology of myocarditis?

Answer 19

Acute or chronic inflammation of the myocardium
Can be in association with pericarditis
Can impair myocardial function, conduction and generate arrhythmia

most common cause is viral

Question 20

Symptoms of myocarditis?

Answer 20

Heart failure with fatigue, SOB, CP in only 26%
Shorter course of a few weeks
May not have fever
Signs of HF

Question 21

Assessment of myocarditis?

Answer 21

ECG usually abnormal
Biomarkers often elevated but not falling in a pattern consistent with MI
Echo, can get RWMA
CMRI can see oedema in certain images
Low threshold for biopsy
Viral DNA PCR
Auto antibodies
Step antibodies
Lyme B burgdorferi
HIV

Question 22

General measures of myocarditis?

Answer 22

Supportive with treatment of heart failure and support for brady and tachy arrhythmias.
Immunotherpay if biopsy or other Ix point to a specific diagnosis
Stop possible drugs or toxic agent exposure

Question 23

What is pericarditis?

Answer 23

Inflammation of the pericardial layers with or without myocardial involvement

Question 24

Pericarditis causes?

Answer 24

vast majority are viral or idiopathic
Key ones to pick up are bacterial, post MI, perforation, dissection of proximal aorta, neoplasia

Question 25

Symptoms of pericarditis?

Answer 25

Usually 1-2/52 duration, chest pain with pleuritic features and postual features, sitting forward usually improves it lying back makes it worse Fever Signs Temp up, pericardial rub LSE, look for JVP as if an effusion is present and substantial or haemodynamically relevant then it will be raised, low BP, muffled HS and raised JVP should make you consider not just pericarditis but effusion High fever and very unwell despite no effusion may suggest bacterial

Question 26

Investigations for pericarditis?

Answer 26

ECG and echo, troponin may be raised if myocardial involvement too

Question 27

Pericarditis ECG?

Answer 27

ECG with widespread ST changes and PR depression of pericarditis

Question 28

General measures for pericardial disease?

Answer 28

Viral is conservative idiopathic gets colchicine and limited use of NSAIDs Bacterial must be drained even if small effusion and antimicrobials, high death rate If large effusion present and some haemodynamic effects then drain

Question 29

Pericardial effusion?

Answer 29

May be haemodynamically significant = tamponade or not Often same causes as pericarditis Where tamponade is present Symptoms are overt, fatige, SOB, dizzy with low BP, occasionally chest pain. Signs are overt as well; pulsus paradoxus, JVP raised, low BP, +/- rub, +/- muffled HS. Pulmoary oedema is very rare in pericardial effusions/tampaonade Key test is urgent echo, CXR can show large cardiac shadow Drainage is the destination treatment Send for MCS, neoplasic cells, protein and LDH, most are exudates Persistent effusion needs a surgical pericardial window made to allow flow to abdomen

Question 30

Constrictive pericarditis?

Answer 30

Causes are idopathic, radiation, post surgery, autoimmune, renal failure, sarcoid. Pathology is that of impaired filling although myocardium is normal most of the time Symptoms of fatigue, SOB, cough Signs more of right heart failure with oedema, ascites, high JVP, jaundice, hepatomegally, AF, TR, pleural effusion, pericardial knock Assess with echo and right heart cath to differentiate from restrictive cardiomyopathy which can be very difficult Treatment is with careful and limited diuretics and pericardectomy