Cardiomyopathy Flashcards
What is meant by cardiomyopathy
A group of diseases of the myocardium that affect the mechanical or electrical function of the heart
4 types of cardiomyopathy
- Hypertrophic
- Dilated
- Restricted
- Arrythmogenic right ventricular
Are cardiomyopathy disorders generally inherited or acquired?
Inherited (tho some are acquired)
Risk factors of cardiomyopathy
Family history of cardiomyopathy High BP Obesity Diabetes Previous MI
What is hypertrophic cardiomyopathy (HCM)
Ventricular hypertrophy/thickening of the muscle
particularly the intraventricular septum
Hypertrophic cardiomyopathy (HCM): epidemiology
Quite common, second most common cardiomyopathy (behind dilated)
• 1/500 people have it
• Autosomal dominant - familial
• May present at any age
• Most common cause of sudden cardiac death in the young
• HCM refers to otherwise unexplained primary cardiac hypertrophy
What is most common cardiomyopathy
Dilated
What is most common cause of sudden cardiac death in young people
Hypertrophic Cardiomyopathy (HCM)
Hypertrophic cardiomyopathy (HCM): Pathophysiology
- Caused by sarcomeric protein gene mutations e.g troponin T and B- myosin
- The hypertrophic, non-compliant ventricles impair diastolic filling resulting in reduced stroke volume and thus cardiac output
- Conduction is also affected in the heart by the disarray of cardiac myocytes
(- All in the absence of hypertension and valvular disease)
Clinical presentation of Hypertrophic Cardiomyopathy
- Sudden death may be the first manifestation
- Chest pain, Angina, dysponea, dizziness, palpitations, syncope
- Left ventricular outflow obstruction may be a feature
- Cardiac arrhythmia
- Ejection systolic murmur
- Jerky carotid pulse
Diagnosis of Hypertrophic Cardiomyopathy
• ECG: is abnormal and shows signs of left ventricular hypertrophy with progressive T wave inversion and deep Q waves
- Echocardiogram: shows ventricular hypertrophy and a small left ventricle cavity
- Genetic analysis can confirm diagnosis since most cases are autosomal dominant and familial
Treatment of Hypertrophic Cardiomyopathy
- Amiodarone - anti-arrythmatic medication, if at high risk of arrhythmia then can place an implantable cardiac defibrillator
- Calcium channel blocker e.g. Verampil
- Beta-blocker e.g. Atenolol
Describe dilated cardiomyopathy
Dilated left ventricle which contracts poorly/has thin muscle
Dilated Cardiomyopathy: Epidemiology
Most common cardiomyopathy
Autosomal dominant - familial
Aetiology of Dilated Cardiomyopathy
Ischaemia
Alcohol
Thyroid disorder
Familial/genetic