Overview of Cardiomyopathies – Cardiovascular Disorders …

A cardiomyopathy is a primary disorder of the heart muscle. It is distinct from structural cardiac disorders such as coronary artery disease, valvular disorders, and congenital heart disorders. Cardiomyopathies are divided into 3 main types based on the pathologic features (see Figure: Forms of cardiomyopathy.):

The term ischemic cardiomyopathy refers to the dilated, poorly contracting myocardium that can occur in patients with severe coronary artery disease (with or without areas of infarction). It is not classically considered to be in the above-listed categories because it does not describe a primary myocardial disorder.

Manifestations of cardiomyopathies are usually those of heart failure and vary depending on whether there is systolic dysfunction, diastolic dysfunction, or both. Some cardiomyopathies may also cause chest pain, syncope, arrhythmias, or sudden death.

Evaluation typically includes family history, blood tests, ECG, chest x-ray, echocardiography, and often cardiac MRI if available. Some patients require endomyocardial biopsy (transvenous right ventricular or retrograde left ventricular). Other tests are done as needed to determine the cause. Treatment depends on the specific type and cause of cardiomyopathy (see Table: Diagnosis and Treatment of Cardiomyopathies).

Diastolic dysfunction outflow obstruction

LV and RV failure, sudden death,

Functional AV valve regurgitation

Exertional dyspnea, angina, syncope, sudden death

Systolic murmur mitral regurgitation murmur, S4

Bifid carotid pulse with a brisk upstroke and rapid downstroke

Exertional dyspnea and fatigue

Functional AV valve regurgitation

Nonspecific ST- and T-wave abnormalities

LV hypertrophy and ischemia

LV hypertrophy or low QRS voltage

Dilated hypokinetic ventricles mural thrombus

Low EF and, frequently, functional AV valve regurgitation

Hypertrophied ventricle, high, normal or low EF, mitral systolic anterior motion asymmetric hypertrophy LV gradient

Increased wall thickness cavity obliteration

Pulmonary venous congestion

Normal or high EDP, low EF, diffusely dilated hypokinetic ventricles AV valve regurgitation

High EDP outflow subvalvular gradient mitral regurgitation

High EDP, dip and plateau diastolic LV pressure curve

20% mortality in first year, and about 10%/yr thereafter

About 1% annual risk of sudden death

Diuretics, ACE inhibitors, angiotensin II receptor blockers, beta-blockers, spironolactone or eplerenone, digoxin, ICD, cardiac resynchronization therapy, anticoagulants

Beta-blockers verapamil disopyramide septal myotomy catheter alcohol ablation

Phlebotomy for hemochromatosis

Hydroxyurea for hypereosinophilia

AV = atrioventricular; BBB = bundle branch block; CO = cardiac output; EDP =end-diastolic pressure; EF = ejection fraction; ICD = implantable cardioverter-defibrillator ; LV = left ventricular; RV =right ventricular; S3 =3rd heart sound; S4= 4th heart sound; = with or without.

Go here to read the rest:

Overview of Cardiomyopathies - Cardiovascular Disorders ...