Exam 1: Cardiomyopathies Flashcards
What is cardiomyopathy?
A myocardial disorder in which the heart muscle is structurally and functionally abnormal in the absence of CAD, HTN, valvular disease, and CHD sufficient to explain the abnormality
What are the 3 main types of cardiomyopathy (CM)?
Dilated, hypertrophic, and restrictive
What is dilated CM pathophysiology?
Symmetric LV dilation and impaired LV systolic function.
What is the presentation of dilated CM (DCM)?
Exertional intolerance with SOB and fatigue, chest pain, palpitations, and peripheral edema
What are some possible PE findings in DCM?
Mitral/tricuspid regurg, s3 gallop, increased JVP, and basal crackles
What is idiopathic DCM?
When there is no identifiable cause, accounts for up to 50% of all DCM cases
What is the primary indication for cardiac transplant?
Idiopathic DCM
What is infectious DCM?
Myocarditis: an inflammatory process secondary to infectious or non infectious causes. Most commonly viral in the US.
What is the gold standard for diagnosis of infectious DCM?
Endomyocardial biopsy, although not always required because a general work up is completed first
What is the presentation of pericardium DCM?
- generally at 36 weeks of gestation though 5 months postpartum.
- Dyspnea, orthopnea, PND, pedal edema, cough, and hemoptysis
What are the risk factors for pericardium DCM?
> 30 yo, African descent, multifarious, history of preeclampsia, material cocaine abuse, and >4 wks of oral tocolytic
What is the presentation of alcoholic DCM?
HF symptoms in conjunction with signs of long term alcohol abuse
What is the prognosis of alcoholic DCM?
- Abstinence can lead to significant improvement in heart failure
- if continued use, poor prognosis with mortality of 50% at 3-6 yrs
What causes DCM in cocaine use?
- toxic effects to the myocardium and myocarditis
- cessation of cocaine may reverse myocardial dysfunction
What drug is a common cause of chemotherapy induced DCM?
Anthracyclines, dose dependent
When starting a patient on anthracyclines for chemotherapy, what should you do to prevent DCM?
Obtain a baseline echo to measure EF and continue to monitor
What 3 things cause endocrine dysfunction DCM?
DM, thyroid dysfunction, and pheochromocytoma
How does DM cause DCM?
Initially myocardial fibrosis and diastolic dysfunction (restrictive CM) and later stages have systolic dysfunction
When a patient has endocrine dysfunction DCM, cardiac dysfunction can be reverse by **
Correction of the endocrine disorder
What two nutritional deficiencies can cause DCM?
Thiamine (B1) and carnitine deficiency
How does carnitine deficiency cause DCM?
There is impaired oxidation of fatty acids, resulting in lipid accumulation in myocyte cytoplasm
What is the diagnostic study of choice for DCM?
Echo
What might you see on CXR of a patient with DCM?
Cardiomegaly and pleural effusions
What is the first line medication for DCM?
ACE inhibitors- reduced afterload by vasodilation and reduces BP
What medications can be given for DCM?
ACE, diuretics, B blockers, digoxin, antiarrhythmics, and anticoagulants
What are the two surgical options for DCM?
Implanted cardioverter defibrillator or cardiac transplantation
What is the pathophysiology of HCM?
Left ventricular hypertrophy in the absence of a cause
What is the histological hallmark in HCM?
Myocyte hypertrophy and disarray with interstitial fibrosis
What is the leading cause of sudden cardiac death in young people?
HCM
What is the etiology of HCM?
Familial
What factors worsen left ventricular outflow in obstructive HCM?
Tachycardia, hypovolemic, standing, valsalva, positive inotropes, diuretics, and vasodilators
What are potential PE finding on LVOT obstruction HCM?
Brisk bifid carotid pulse, audible S4, crescendo decrescendo ejection murmur that increases with valsalva and standing, but decreases with squatting and isometric handgrip
What is the diagnostic study of choice for HCM?
Echo, showing Increased LV wall thickness.
What changes will you see on EKG in a patient with HCM?
LVH with strain
What is the management for asymptomatic HCM?
No prophylactic therapy
What is the management for symptomatic HCM?
- Beta blockers or non-dihydropyridine CCBs (- inotrope)
- Diuretisc with caution if significant LVOT obstruction
- Manage arrhythmias
- ICD implantation if high risk for sudden cardiac death
When is surgery for HCM indicated? What are the surgical options?
- Indicated for symptomatic LVOT obstruction with advanced HF refractory to medical therapy
- Surgical septal myectomy, EtOH ablation, or mitral valve surgery
What is the pathophysiology of RCM?
- Non-dilated, rigid ventricles with diastolic dysfunction and restrictive filling
- Preserved systolic function (HFpEF)
What can RCM resemble?
Constrictive pericarditis
What is constrictive pericarditis?
Scarring and consequential loss of the normal elasticity of the pericardial sac, impaired ventricular filling
What is the least common CM?
Restrictive
What are the etiologies of RCM?
- Infiltrative: Amyloidosis and sarcoidosis
- Storage disease: hemochromatosis, glycogen storage disease
- other: idiopathic, scleroderma, and fibrosis secondary to chemo/radiation
What is the most common cause of RCM?
Amyloidosis
What are the common symptoms of RCM?
- Right > left heart failure (edema, abdominal discomfort, and ascites)
- Angina, syncope, and dyspnea
What are the PE findings of RCM?
S3 gallop (Not heard in constrictive pericarditis!!), prominent JCP, possibly kussmauls sign, and possible MR/TR murmur
What is the presentation of Cardiac Amyloidosis?
- Periorbital purpura with HF is pathognomonic
- Hepatomegaly, ascites, and elevated JVP
What is the diagnostic study that gives a definitive diagnosis of cardiac Amyloidosis?
Endomyocardial biopsy
What will you see on an echo in a patient with cardiac Amyloidosis?
Increased left ventricular wall thickness with diastolic dysfunction, later RV diastolic dysfunction develops
What is the management for RCM?
- treat underlying cause
- low dose loop diuretics
- transplant consideration
- Poor prognosis
What is takotsubo CM (TCM) also known as?
Stress CM, apical ballooning syndrome, and broken heart syndrome
What is TCM?
Transient LV systolic and diastolic dysfunction in the absence of attributable CAD
-often precede by emotional or physical trigger
What is the presentation of TCM?
- abrupt onset
- similar to ACS with substernal CP, SOB, and syncope
- Symptoms of HF
Is Troponin elevated in TCM?
Yes
What will you see on EKG of TCM?
ST segment elevation, deep anterior T wave inversions which gradually resolve
What is the management of TCM?
- Immediate and similar to any acute MI including cath lab
- resolve trigger
