Dilated Cardiomyopathy, Restrictive & Infiltrative Cardiomyopathy, Hypertrophic Cardiomyopathy (pathology) Flashcards
What is dilated cardiomyopathy?
Ventricular function/ejection is impaired
- One or more often all chambers are dilated and functionally impaired
- Fibrosis and replacement of myocardium with scar
Poor prognosis generally
What is the aetiology of dilated cardiomyopathy?
Can be a primary problem or secondary to:
• Ischaemia
• Valvular causes
• Genetic/ familial SCN5A gene, muscular dystrophy
• Inflammatory, infectious, autoimmune, postpartum
• Toxic: drugs, exogenous chemicals, endocrine
• Injury, cell loss, scar replacement
What are the symptoms of dilated cardiomyopathy?
- Slow onset
- Dyspnoea
- Orthopnoea
- Fatigue
- Paroxysmal nocturnal dyspnoea
- Ankle swelling
- Weight gain of fluid overload
- Cough
What are the signs of dilated cardiomyopathy?
- Poor superficial perfusion
- Low volume pulse
- Irregular pulse if in AFib
- SOB at rest
- Narrow pulse pressure
- ↑JVP +/- Tricuspid regurgitant
- Displaced apex
- S3 & S4
- Pansystolic murmur of mitral regurgitation
- Pulmonary oedema
- Pleural effusion
- Ankle and sacral oedema
- Ascites
- Hepatomegaly
What are the investigations for dilated cardiomyopathy?
ECG - Repeated, note if LBBB CXR BNP to justify echo Bloods - U&Es - FBC - LFTs - Endocrine function Echo CMRI – Gold standard Coronary angiogram Biopsy (sometimes)
What is the management for dilated cardiomyopathy?
correct anaemia
- remove exacerbating drugs (NSAIDs- retain Na+, H2O)
- correct endocrine problems
- fluid and salt intake
- manage weight
- HF nurse referral
What is the pharmacological/surgical treatment for dilated cardiomyopathy?
- ACEi
- ARBs
- Diuretics
- VALSARTAN-SACUBITRIL
- Beta blockers
- Spironolactone
- Anticoagulants for thrombus or AFib
- Implantable defibrillator or Cardiac recentralisation pacing system (CRT-D/P)
- Cardiac transplant
What is restrictive and infiltrative cardiomyopathy?
Reduced compliance of ventricular wall-> impaired filling -> atrial dilatation
*Relaxation of ventricular wall is an active process that needs functioning intact myocytes
Poor prognosis unless reversible
Aetiology of non-infiltrative cardiomyopathy
- Familial
- Forms of hypertrophic cardiomyopathy
- Scleroderma
- Diabetes
- Pseudoxanthoma elasticum
Aetiology of infiltrative cardiomyopathy
- Amyloid
- Sarcoid
Investigations for restrictive and infiltrative cardiomyopathy
ECG - Repeated noting LBBBB or other conduction defects CXR BNP – elevated in Cardiomyopathy Bloods - FBC - U&E -> look for sarcoid & hemochromatosis - autoantibodies for scleroderma - non cardiac biopsy for amyloid - low plasma alpha galactosidase A activity- Fabry Echo CMRI- gold standard Biopsy - Useful but high false negative rate
Treatment for restrictive and infiltrative cardiomyopathy
- Limited diuretic and ACEi use because decrease filling pressure and exacerbate fluid overload
- Beta blockers
- Anticoagulants if AFib or thrombus
- ICD or CRT-D/P but limited evidence
- Cardiac transplant
• If cause is iron overload, amyloid or Fabry’s= specific treatment available
• Endomyocardial fibrosis= little specific treatment
What is hypertrophic cardiomyopathy
Impaired relaxation (diastole) - = decreased compliance Systolic function normal but with some functional abnormality
What is the aetiology of hypertrophic cardiomyopathy?
- Mostly genetic causes (family history very important)
- Defect in sarcomere gene- AUTOSOMAL DOMINANT
- VARIABLE EXPRESSION & INCOMPLETE PENETRANCE
What are the symptoms of hypertrophic cardiomyopathy?
- Asymptomatic for many
- Fatigue
- Palpitations
- Dyspnoea
- Anginal like chest pain
- Exertional pre-syncope
- Syncope due to arrhythmias or left ventricular outflow tract obstruction
- HF like symptoms
