Cardiomyopathy, Myocarditis and Pericarditis

Question 1

Briefly describe what dilated cardiomyopathy is and it’s main characteristics

Answer 1

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

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

Question 2

Describe the etiological background of dilated cardiomyopathy whilst excluding vascular and ischaemic causes.

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

Describe symptoms of dilated cardiomyopathy

Answer 3

Symptoms
Progressive, slow onset, dyspnoea, fatigue, orthopnoea, PND, ankle swelling, weight gain of fluid overload, cough.
PMH; systemic illness, travel, HT, vascular disease, thyroid, neuromuscular disease

Question 4

Describe signs/ findings of examination of dilated cardiomyopathy

Answer 4

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 5

Describes investigations of dilated cardiomyopathy

Answer 5

Basic evaluation
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 6

General measures in treatment of dilated cardiomyopathy

Answer 6

General measures in treatment
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

Question 7

More specific measures in treatment of dilated cardiomyopathy

Answer 7

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 the prognosis of dilated cardiomyopathy

Answer 8

generally poor and often influenced by the causes where known

Question 9

Define and describe the characteristics of restrictive and infiltrative cardiomyopathy

Answer 9

Less common, again describes the physiology of filling and myocyte relaxation capacity, the systolic function may or not be impaired.

About 50% are related to specific clinical disorders, the rest remain unknown

Question 10

Describes causes of different forms of restrictive and infiltrative of cardiomyopathy

Answer 10

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 11

Pathophysiology of restrictive and infiltrative cardiomyopathy

Answer 11

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 12

Restrictive and infiltrative cardiomyopathy investigations

Answer 12

Basic evaluation
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 13

Restrictive and infiltrative cardiomyopathy measures for treatment. (also prognosis)

Answer 13

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

Unless reversible poor prognosis

Question 14

Describe hypertrophic cardiomyopathy

Answer 14

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

Question 15

Describe genetics of hypertrophic cardiomyopathy

Answer 15

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 16

Pathology of hypertrophic cardiomyopathy

Answer 16

Pathology
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 17

Symptoms and signs of hypertrophic cardiomyopathy

Answer 17

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 18

Investigations for hypertrophic cardiomyopathy

Answer 18

Assessment
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 19

General and specific measures for treatment of hypertrophic cardiomyopathy.

Answer 19

General measures
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 20

Describe myocarditis

Answer 20

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

Long list of possible causes………
However often the cause is not found despite investigations

Can eventually take on the dilated cardiomyopathy appearance

Question 21

Pathology of myocarditis

Answer 21

Pathology
Infiltration of inflammatory cells into the myocardial layers, reduced function and heart failure, heart block as conduction system is involved and arrhythmias

Question 22

Symptoms of myocarditis

Answer 22

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

Question 23

Investigation for myocarditis

Answer 23

Assessment
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 24

General measures of treatment and prognosis of myocarditis

Answer 24

General measures
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
Prognosis
30% recovery fully but 20% mortality at 1 year and 56% by 4 years. At 11 years those still alive are 93% transplant free.

Question 25

What is pericardium

Answer 25

Pericardium is a reflected lining over the epicardium (the viceral pericardium) and the parietal pericardium that is the inner portion of the exterior sac around the heart and proximal great vessels

Question 26

Describe pericarditis

Answer 26

Pericarditis
Inflammation of the pericardial layers with or without myocardial involvement
Substantial numbers of causes

Question 27

Symptoms and sings of pericarditis

Answer 27

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

Question 28

ECG findings in pericardial disease

Answer 28

ECG with widespread ST changes and PR depression of pericarditis

Question 29

General measures of treatment for pericarditis

Answer 29

General measures
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 30

Pericardial effusion description

Answer 30

May be haemodynamically significant = tamponade or not
Often same causes as pericarditis
Where tamponade is present

Question 31

Symptoms and signs of pericardial effusion

Answer 31

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

Question 32

Key investigations and treatment of pericardial effusion

Answer 32

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 33

ECG findings in pericardial effusion

Answer 33

ECG with electrical alternans in a large effusion

Question 34

Describe pathology and causes of constructive pericarditis

Answer 34

Rare
Causes are idopathic, radiation, post surgery, autoimmune, renal failure, sarcoid.
Pathology is that of impaired filling although myocardium is normal most of the time

Question 35

Signs and symptoms of constructive pericarditis

Answer 35

Symptoms of fatigue, SOB, cough
Signs more of right heart failure with oedema, ascites, high JVP, jaundice, hepatomegally, AF, TR, pleural effusion, pericardial knock

Question 36

Investigations and treatment of constructive pericarditis

Answer 36

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