Cardiomyopathy, Myocarditis and Pericarditis Flashcards
What is cardiomyopathy?
Cardiomyopathy is a group of diseases that affect the heart muscle.
What are the 3 main types of cardiomyopathy?
- Hypertrophic cardiomyopathy (HCM)
- Dilated cardiomyopathy (DCM)
- Arrhythmogenic right ventricular cardiomyopathy (ARVC)/ restrictive
What are the main types of pericardial disease?
Pericarditis and effusion +/- tamponade
Features of dilated cardiomyopathy
In dilated cardiomyopathy the ventricles enlarge and weaken.
- Can be one but more often all chambers dilated and functionally impaired. Thrombosis in chambers is not uncommon.
What are associations (causes) of dilated cardiomyopathy?
- Alcohol
- Increased BP
- Chemotherapeutics
- Haemochromatosis
- Viral infection
- Autoimmune
peri- or postpartum - Thyrotoxicosis
- Congenital (X-linked)
Symptoms of dilated cardiomyopathy
- Fatigue
- Dyspnoea
- Pulmonary oedema
- RVF
- Emboli
- Atrial fibrillation
Signs of dilated cardiomyopathy
- Increased pulse
- Decreased blood pressure
- Increased JVP
- Displaced and diffuse apex
- Mitral or tricuspid regurgitation
- Pleural effusion
- Oedema
- Jaundice
- Hepatomegaly
- Ascites
Common past medical history for dilated cardiomyopathy
- Systemic illness
- Travel
- HT
- Vascular disease
- Thyroid
- Neuromuscular disease
Tests for dilated cardiomyopathy
- Blood: decreased Na+ indicated a poor prognosis.
- CXR: cardiomegaly, pulmonary oedema
- ECG
- Echocardiogram
General measures in treatment of dilated cardiomyopathy
- Correct anaemia
- Remove exacerbating drugs e.g. NSAIDs
- Correct any endocrine disturbance
- Advise on fluid and salt intake, reduce it
- Advise on managing weight to identify fluid overload
Treatments for dilated cardiomyopathy
- Diuretics
- Beta blockers
- ACEi
- Anticoagulation
- Biventricular pacing
- Transplantation
Prognosis of dilated cardiomyopathy
Generally poor and often influenced by the causes where known
Features of restrictive cardiomyopathy
- In restrictive cardiomyopathy the ventricle stiffens.
- Less common, 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.
Causes of restrictive cardiomyopathy
- Idiopathic
- Amyloidosis
- Haemochromatosis
- Sarcoidosis
- Scleroderma
- Endocarditis
Basic diagnosis evaluation for restrictive cardiomyopathy
- Repeated ECG noting LBBB if present and other conduction defects
- CXR
- N terminal brain natriuretic peptide
- Basic bloods
- Auto antibodies for sclerotic CT diseases
- Amyloid needs non cardiac biopsy to help establish the diagnosis
- Echocardiogram
- CMRI
- Biopsy more helpful but still has high false negative rate
Treatment and specific measures for restrictive cardiomyopathy
- Limited diuretic use as low filling pressures will cause problems
- Beta blockers limited ACEi use
- Anticoagulants as required
- SCD risk assessment
- Cardiac transplant
- If iron overload, specific forms of amyloid or Fabrys then specific treatments are available
- Endomyocardial fibrosis has little specific treatment
Prognosis of restrictive cardiomyopathy
Unless reversible then poor prognosis
Features of Hypertrophic cardiomyopathy
- Impaired relaxation is a common feature and systolic function is usually adequate albeit with some functional abnormality.
- Relatively high prevalence 1:500
- Sarcomere gene defect. Autosomal dominant but!!
In hypertrophic cardiomyopathy the heart muscle enlarges and thickens.
Pathology of hypertrophic cardiomyopathy
- 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.
Are coronary arteries affected due to hypertrophic cardiomyopathy?
Coronary arteries also affected with small vessel narrowing and consequent ischaemia and fibrosis, arrhythmias are common
Symptoms of Hypertrophic cardiomyopathy
- Breathless
- Palpitations
- Syncope
- Exertional symptoms
- SCD
- Angina
- Dyspnoea
Asymptomatic for many
Examination findings in Hypertrophic cardiomyopathy
- Can be none
- Notched pulse pattern
- Irregular pulse if in AF or ectopy
- Double impulse over apex, thrills and murmurs, often dynamic, LVOT murmur will increase with valsalva manoeuvre and decrease with squatting.
- JVP can be raised in very restrictive filling
General measures for hypertrophic cardiomyopathy
- Avoid heavy exercise
- Avoid dehydration
- Explore FH and first degree relatives, ECGs and echoes may be required
- Consider genetic testing
- Regular FU to reappraise the risks and progress
Specific (treatment) measures in hypertrophic cardiomyopathy
- 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
Investigation assessments for hypertrophic cardiomyopathy
- 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
What is Myocarditis?
Acute or chronic inflammation of the myocardium
- Can be in association with pericarditis .
- Can impair myocardial function, conduction and generate arrhythmia.
Pathology of myocarditis
Infiltration of inflammatory cells into the myocardial layers, reduced function and heart failure, heart block as conduction system is involved and arrhythmias
Signs and symptoms of myocarditis
- Heart failure symptoms
- Palpitations
- Tachycardia
- Soft S1, S4 gallop
Investigation assessments for myocarditis
- 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
- Strep antibodies
- Lyme B burgdorferi
- HIV
General measures for myocarditis
- Supportive with treatment of heart failure and support for brady and tachy arrhythmias
- Immunotherapy if biopsy or other lx point to a specific diagnosis
- Stop possible drugs or toxic agent exposure
Prognosis of Myocarditis
30% recovery fully but 20% mortality at 1 year and 56% by 4 years.
At 11 years those still alive are 93% transplant free.
What is the pericardium?
It is a reflected lining over the epicardium (the visceral pericardium) and the parietal pericardium that is the inner portion of the exterior sac around the heart and proximal great vessels.
What is Pericarditis?
Inflammation of the pericardial layers with or without myocardial involvement.
What are the causes of pericarditis?
THere is a SUbstantial number of CAuses
Do we need to know them? (idk)
Symptoms of pericarditis
- Central chest pain worse on inspiration or lying flat.
- Relieved by sitting forward.
- A pericardial friction rub may be heard
- Fever
Signs of pericarditis
- Increased temperature
- Pericardial rub LSE
- Look for JVP as if an effusion is present
- Low blood pressure
- Muffled HS
- Raised JVP should make you consider not just pericarditis but effusion
- High fever and very unwell despite no effusion may suggest bacterial investigations.
- Troponin may be raised if myocardial involvement to.
General measures for pericarditis
- 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.
What is pericardial effusion?
Accumulation of fluid in the pericardial sac
Causes of pericardial effusion
- Pericarditis
- Myocardial rupture
- Aortic dissection
- Pericardium filling with pus
- Malignancy
Features of pericardial effusion
- May be haemodynamically significant = tamponade or not
- Often same causes as pericarditis
- Where tamponade is present
Symptoms of pericardial effusion
- Dyspnoea
- Fatigue
- Dizzy with low BP
- Chest pain
- Nausea (diaphragm)
- Bronchial breathing at left base
- Muffled heart sounds
Signs of pericardial effusion
- Pulsus paradoxus
- JVP raised
- Low BP +/- rub
- Pulmonary oedema is very rare in pericardial effusions/tamponade
What is a key test and investigations in pericardial effusion?
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
Features of constrictive pericarditis
The heart is encased in a rigid pericardium.
- This is rare
Pathology of constrictive pericarditis
Pathology is that of impaired filling although myocardium is normal most of the time
Symptoms of constrictive pericarditis
- Fatigue
- SOB
- Cough
Signs of constrictive pericarditis
- Signs more of right heart failure with oedema
- Ascites
- High JVP
- Jaundice
- Hepatomegally
- AF
- Pleural effusion
- Pericardial knock
What is a pericardial knock?
Diastolic sound caused by loss of pericardial elasticity that limits ventricular filling
Investigation techniques for constrictive pericarditis
Assess with echo and right heart catheter to differentiate from restrictive cardiomyopathy which can be very difficult
Treatment of constrictive pericarditis
Treatment is with careful and limited diuretics and pericardectomy
