Cardiomyopathy Flashcards
(35 cards)
Definition of Cardiomyopathy
Structural or functional abnormality of the myocardium, independent of any other valvular, coronary, or myocardial involvement in systemic disease.
Dilated Cardiomyopathy
Dilated LV, cardiomegaly, impaired systolic function, increased myocardial mass, increased predisposition of intra-cardiac thrombi.
Etiology of DCM
Idiopathic, viral (Coxsackie B, Parvovirus B19), Sarcoidosis, chronic alcohol abuse, hypothyroidism, muscular dystrophy.
Effect of DCM on EDP?
Decreases EDP and decreases CO – LV can’t squeeze blood out. Decrease in renal perfusion, increases in RAAS, which increases PVR and causes dilation of all 4 chambers and causes CHF.
Symptoms of DCM?
CHF! Dyspnea, orthopnea, PND, peripheral edema, fatigue.
Signs of DCM
Gallop rhythm, rales, JVD, edema, tachycardia
Xray of DCM shows
Cardiomegaly and signs of HF (boggy lungs)
EKG of DCM shows
Nothing specific, can show a number of abnormalities.
Echo of DCM shows
Chamber dilatation. Very valuable.
Cardiac cath of DCM
Do a biopsy to confirm diagnosis.
Treatment of DCM
Diuretics to reduce preload ACEI/ARB Beta Blocker (actually upregulates B receptors) Aldosterone antagonists Last 3 actually reduce mortality
Also need to anticoagulate
Hypertrophic cardiomyopathy
Assymetric hypertrophy of the LV septum (not caused by chronic pressure overload)
Etiology of hypertrophic cardiomyopathy?
Autosomal dominant inheritance, but much fewer people develop HCM than have the mutation, so clearly some epigenetic factors.
Pathology of HCM and disease states
Myofiber disarray -> Ventricular arrythmias –> Sudden death or syncope
LVH –> Impaired relaxation –> Increased filling pressure –> Dyspnea, also increased myocardial oxygen demand, and angina
Dynamic LV outflow obstruction –> increased systolic pressure, mitral regurg, failure to increase CO with exertion. Causes dyspnea
Symptoms of HCM
Dyspnea, angina, syncope, sudden cardiac death
Signs of HCM
S4 (ventricle is stiff, atria need to contract hard to fill)
Effect of Valsalva on HCM systolic murmur
Gets louder because venous return reduces, and murmur of obstruction increases
Effect of squatting on HCM systolic murmur
gets quieter because increased venous return
Describe HCM murmur
Crescendo-decrescendo at LLSB
Best diagnostic test for HCM
Echo, will show asymmetrical hypertrophy of the LV septum
Treatment of HCM?
Beta Blockers- will decrease myocardial oxygen demand, decrease LV outflow gradient, increase diastolic filling, decrease frequency of bad ventricular beats.
Calcium channel blockers
Diuretics for overt CHF
Amiodarone for arrythmias
What to avoid with HCM
Vasodilators and digoxin.
Restrictive cardiomyopathy
Less common than the other two. Diastolic dysfunction with preserved systolic function. Causes horrible CHF.
Causes of RCM
Noninfiltrative – idiopathic
Infiltrative – amyloidosis, sarcoidosis,
Storage- hemochromatosis
Tropical environment
