Flashcards in Cardiomyopathy Deck (6):
What is cardiomyopathy?
Cardiomyopathy refers to a collection of disease processes affecting the heart muscle that cause impaired pumping of the involved muscle. There are 3 main types:
Dilated cardiomyopathy - Most common type of cardiomyopathy. Caused by dilation of the ventricles (Just left or Both)
Hypertrophic cardiomyopathy – Left sided ventricular hypertrophy, leading to left ventricular outflow obstruction. It is autosomal dominant
Restrictive cardiomyopathy – The heart muscle becomes rigid (but not dilated or hypertrophied like in the above conditions) causing impaired diastolic filling
What are the causes of cardiomyopathy?
Dilated cardiomyopathy – Myocardial Ischaemia, Alcoholic, Hypertension, Hyperthyroidism, Idiopathic
Hypertrophic cardiomyopathy – Congenital (Autosomal Dominant), Hypertension
Restrictive cardiomyopathy - Idiopathic, Sarcoidosis, Amyloidosis, TB, Haemochromatosis
What will you find on a history taking of cardiomyopathy?
Dilated cardiomyopathy – Congestive Heart Failure (Left side worst affected), AF, Ventricular tachycardia
Hypertrophic cardiomyopathy - Congestive Heart Failure, Chest Pain, Palpitations, Syncope, SOB, Sudden death/Ventricular Fibrillation (commonly in young athletes)
Restrictive cardiomyopathy - Congestive Heart Failure (Right side worst affected), AF, Ventricular tachycardia
Specific Questions to ask:
Family history of sudden cardiac death -Think hypertrophic cardiomyopathy
What will you find on examination of a patient with cardiomyopathy?
Dilated Cardiomyopathy – Tachycardia, Hypotension, Raised JVP, Displaced/Diffuse apex beat, S3 Gallop Rhythm, Signs of heart failure
Hypertrophic cardiomyopathy – Jerky Pulse, Double apex beat, S4 heart sound, Alpha wave in JVP, Systolic thrill at lower left sternal edge and ejection systolic murmur, LVH
Restrictive Cardiomyopathy - Kussmaul’s/Pulsus paradoxes, S3 and S4 heart sounds, non-palpable apex beat, Prominent X/Y descent in JVP, Signs of heart failure
What investigations will you order in cardiomyopathy?
Dilated Cardiomyopathy – T wave changes (nonspecific) and poor R wave progression
Hypertrophic cardiomyopathy - LVH (Tall QRS V5/6), Progressive T wave inversion, Pathological Q wave in inferior and lateral leads, Arrhythmias (AF, WPW, VT, VF)
FBC – Looking for infection/Precipitating anaemia
U&E – Dilated cardiomyopathy associated with hyponatraemia
LFTs – Congestive heart failure can affect the liver
Troponin – Rule out MI as cause of chest pain
TFT – Thyrotoxicosis is a cause of dilated cardiomyopathy
BNP – Assess ventricular involvement
CXR – Cardiomegaly and signs of heart failure
Echocardiogram – Diagnostic test
Transthoracic Doppler Echocardiography
Dilated Cardiomyopathy – Globally dilated hypokinetic heart muscle with poor ejection fracture
Hypertrophic cardiomyopathy – Asymmetrical septal hypertrophy
ECG stress test to rule out ischaemic heart disease that may be predisposing
Cardiac catheterisation - help in excluding coronary artery disease as a cause