Cardiomyopathies Flashcards
What is the contemporary definition of cardiomyopathy?
A myocardial disorder in which the heart muscle is structurally and functionally abnormal without coronary artery disease, hypertension, valvular disease, or congenital heart disease.
What are the three main types of cardiomyopathies?
Dilated, Hypertrophic, and Restrictive Cardiomyopathy.
Which cardiomyopathy is the most common?
Dilated Cardiomyopathy (DCM), accounting for up to 60% of cases.
What is the WHO 1980 definition of cardiomyopathy?
Heart muscle disease of unknown cause.
How does the AHA 2006 define cardiomyopathies?
A heterogeneous group of diseases of the myocardium associated with mechanical and/or electrical dysfunction, often genetic, and can lead to heart failure or death.
What are the classifications of cardiomyopathy according to WHO/ISFC 1995?
Dilated, Hypertrophic, Restrictive, Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC), and Unclassified Cardiomyopathy.
What is the primary characteristic of Dilated Cardiomyopathy (DCM)?
Dilation and impaired systolic function of the left or both ventricles with an ejection fraction <40%.
What are the main causes of Dilated Cardiomyopathy?
Genetic mutations, myocarditis, toxins (alcohol, drugs), endocrine disorders, nutritional deficiencies, pregnancy, and infections.
Which infection is commonly associated with DCM in Nigeria?
Toxoplasma gondii and Coxsackievirus B.
What are the clinical features of Dilated Cardiomyopathy?
Heart failure symptoms, acute pulmonary edema, systemic or pulmonary embolism, and syncope.
What is the characteristic ECG finding in DCM?
Sinus or atrial tachycardia, atrial fibrillation, low voltage complexes, left axis deviation, and conduction abnormalities.
What echocardiographic findings suggest DCM?
Dilated chambers, thin walls, global hypokinesia, LVEF <40%, and mural thrombi.
What is the role of diuretics in DCM treatment?
They help manage fluid overload but do not improve survival.
Which drug classes are essential for DCM management?
ACE inhibitors, Beta-blockers, Aldosterone antagonists, and SGLT2 inhibitors.
What is Hypertrophic Cardiomyopathy (HCM)?
Unexplained left ventricular hypertrophy (LVH) in the absence of other causes such as hypertension or aortic stenosis.
What is the prevalence of HCM in the general population?
Approximately 1 in 500 people.
Which genetic mutation is most commonly associated with HCM?
Beta-myosin heavy chain gene mutation.
What is the main histological feature of HCM?
Myofibrillar disarray with fibrosis.
What are the key clinical features of HCM?
Chest pain, dyspnea, syncope, arrhythmias, and systolic murmur.
What are the ECG findings in HCM?
LVH, ST-T wave abnormalities, and deep Q waves in lateral leads.
What is the first-line drug treatment for symptomatic HCM?
Beta-blockers or non-dihydropyridine calcium channel blockers (e.g., verapamil).
Which interventions are considered for high-risk HCM patients?
Implantable cardioverter-defibrillator (ICD) for sudden cardiac death prevention.
What is Restrictive Cardiomyopathy (RCM)?
A condition characterized by impaired diastolic function due to reduced ventricular compliance with near-normal systolic function.
What are the common causes of RCM?
Amyloidosis, sarcoidosis, endomyocardial fibrosis, and Loeffler’s endocarditis.
What is the hallmark clinical feature of RCM?
Severely limited exercise tolerance due to fixed stroke volume.
What are the echocardiographic features of RCM?
Bi-atrial enlargement and restrictive mitral inflow pattern.
What is the treatment focus for RCM?
Managing symptoms of heart failure and addressing the underlying cause.
Which cardiomyopathy is commonly associated with sudden cardiac death in young athletes?
Hypertrophic Cardiomyopathy (HCM).
Which genetic inheritance pattern is seen in most cases of HCM?
Autosomal Dominant.
What is the recommended screening for family members of a patient with HCM?
Echocardiography and ECG for first-degree relatives.
