Cardiomyopathy and Heart Failure Flashcards
cardiomyopathy is A heterogeneous group of diseases of the myocardium associated with ________dysfunction that usually exhibit inappropriate ventricular hypertrophy or dilation
mechanical and/or electrical
cardiomyopathy May be primary or _______. It May also be genetic or _______, or have elements of both
secondary acquired
what are the classifications of cardiomyopathy?
- Dilated cardiomyopathy (DCM) 2. Hypertrophic cardiomyopathy (HCM) 3. Restrictive cardiomyopathy (RCM) 4. Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) 5. Unclassified cardiomyopathies
Systolic dysfunction is usually associated with what type of cardiomyopathy?
dilated cardiomyopathy sometimes hypertrophic
in cardiomyopathy with Systolic dysfunction, _______ is most affected
Myocardial contractility
cardiomyopathy with Systolic dysfunction frequently results in reduction of what?
left ventricular ejection fraction (EF)
Cardiomyopathy with Diastolic dysfunction has what effect ton ejection fraction?
EF may be normal or somewhat reduced
Diastolic dysfunction is usually associated with what type of cardiomyopathy?
Usually associated with restrictive cardiomyopathy, sometimes hypertrophic
in cardiomyopathy with Diastolic dysfunction, what happens in regards to the left ventricle and pressures?
LV relaxation and filling is abnormal with elevated filling pressures
how is Dilated Cardiomyopathy characterized?
Characterized by dilation and impaired contraction of one or both ventricles
dilation and impaired contraction of one or both ventricles is what type of cardiomyopathy?
dilated
what are common causes of dilated cardiomyopathy?
Common causes include gene mutations, toxicity (chronic alcoholism), myocarditis (virus infection), pregnancy-associated, or idiopathic (no known cause)
Dilated Cardiomyopathy is Usually accompanied by an increase in total _____ (hypertrophy)
cardiac mass
Dilated Cardiomyopathy Impairs systolic function with marked reduction in EF and CO, results in_____.
heart failure
Are “Ischemic cardiomyopathy” or “valvular cardiomyopathy” considered dilated cardiomyopathies?
no “Ischemic cardiomyopathy” or “valvular cardiomyopathy” associated with CAD and valve disease present with ventricular dilation and systolic dysfunction are not true dilated cardiomyopathies per American Heart Association/European Society of Cardiology [AHA/ESC] classification systems
how is Hypertrophic Cardiomyopathy characterized?
Characterized by hypertrophy of the left ventricle (sometimes RV)
hypertrophy of the left ventricle (sometimes RV) is what type of cardiomyopathy?
Hypertrophic Cardiomyopathy
Hypertrophic Cardiomyopathy Impairs ____ function with preserved or moderately reduced EF and reduced CO, heart failure
diastolic
what is Hypertrophic Cardiomyopathy caused by?
Caused by genetic mutations, common (1:500 adults) Autosomal dominant trait with incomplete penetrance
Hypertrophic Cardiomyopathy caused by what kind of genetic trait?
Autosomal dominant trait with incomplete penetrance
what is the most common cause of LVH?
hypertension and aortic stenosis
is LVH caused by HTN or aortic stenosis considered Hypertrophic Cardiomyopathy?
NO
how is Restrictive Cardiomyopathy characterized?
Characterized by nondilated ventricles with impaired ventricular filling, without myocyte hypertrophy
nondilated ventricles with impaired ventricular filling, without myocyte hypertrophy is considered what type of cardiomyopathy?
Restrictive Cardiomyopathy
Restrictive Cardiomyopathy May have _____ enlargement with some infiltrative or storage diseases (e.g., amyloidosis)
ventricular
Restrictive Cardiomyopathy Impairs diastolic function with preserved or moderately reduced EF and reduced CO, results in _____.
heart failure
what causes Restrictive Cardiomyopathy?
Causes include genetic noninfiltrative, infiltrative, and storage diseases, and others disorders (e.g., diabetic cardiomyopathy, scleroderma, endomyocardial fibrosis)
how is Arrhythmogenic Right Ventricular Cardiomyopathy characterized?
Characterized by ventricular arrhythmias and replacement of ventricular myocardium by fibrous and/or fibro-fatty tissue
if you see ventricular arrhythmias and replacement of ventricular myocardium by fibrous and/or fibro-fatty tissue, what kind of cardiomyopathy is it?
Arrhythmogenic Right Ventricular Cardiomyopathy
in Arrhythmogenic Right Ventricular Cardiomyopathy, how is ventricular function?
Ventricular function is abnormal, with regional akinesis / dyskinesis, or global right ventricular dilation and dysfunction
Arrhythmogenic Right Ventricular Cardiomyopathy is genetically determined heart muscle disease, it usually becomes symptomatic in what age group?
young adults
Arrhythmogenic Right Ventricular Cardiomyopathy is usually associated with a reduced ___ and ____.
Usually associated with a reduced EF and reduced CO
what is Stroke volume (SV)?
volume of blood ejected from the LV with each contraction (mL)
how do you determine Cardiac output (CO)?
Cardiac output (CO) = heart rate (HR) x SV
what is Ejection fraction (EF)?
% of LV blood volume ejected per contraction
what is a normal Ejection fraction (EF)?
Normal: 50-70%;
what is a borderline Ejection fraction (EF)?
Borderline: 41-49%;
what is a reduced Ejection fraction?
Reduced: ≤ 40%
what is preload?
end-diastolic chamber stretch (related to the volume of blood preparing to enter the chamber)
what is afterload?
contractile force required to eject blood (related to blood pressure in the aorta or pulmonary artery)
what is contractility?
ability of cardiac muscle fibers to contract with a given preload and afterload, related to cytosolic calcium availability
Stroke volume increases in response to an increase in ____.
preload
increasing ______volume results in more than normal myocyte stretch, resulting in a more forceful contraction (enhances contractility)
end-diastolic
Suddenly increasing end-diastolic volume results in more than normal myocyte stretch, resulting in a more forceful contraction (enhances contractility). This May be perceived as “_______”, e.g., after a PAC or PVC (since the chamber empties early there will be greater preload with the next contraction, therefore a more forceful contraction)
palpitation
Past a certain point there is no additional gain in SV, and eventually SV will fall with even more _____.
stretch
Normally the heart functions midway up the inclining slope allowing adjustment of ____ in both directions
SV
heart failure results in Reduced cardiac output and reduced tissue perfusion which can result from dysfunction of what two things?
Systolic dysfunction Diastolic dysfunction
what does Systolic dysfunction cause?
insufficient myocardial contractility to provide adequate perfusion (reduced CO and EF)
what does diastolic dysfunction cause?
insufficient ventricular relaxation / distensability for ventricles to receive available atrial blood during diastole (reduced CO and normal to moderately reduced EF)
Heart Failure with Systolic Dysfunction Refers to a decrease in ______
myocardial contractility
in Heart Failure with Systolic Dysfunction, The slope of the Frank-Starling relationship between LVEDP and SV is reduced and the curve is shifted to the ___ (larger LVEDP needed to maintain SV)
right
in heart failure ventricular remodeling, there is 3 remodeling patterns, what are they?
Concentric hypertrophy Eccentric left ventricular hypertrophy Myocardial remodeling post-infarction
Concentric hypertrophy remodeling causes what to wall size and cardiomyocytes? (has what effect on the heart?
Increased relative wall thickness compared to cavity size Cardiomyocyte hypertrophy
Concentric hypertrophy remodeling is caused by what?
pressure overload (e.g., HTN, obstruction)
Eccentric left ventricular hypertrophy remodeling is caused by what?
volume overload
Eccentric left ventricular hypertrophy remodeling has what effect on the heart?
Increased cardiac mass and chamber volume (relative wall thickness may be normal, increased, or decreased) Cardiomyocyte hypertrophy with chamber enlargement
Myocardial remodeling post-infarction has what effect on the heart?
Infarcted tissue stretches, increasing left ventricular volume leading to combined volume and pressure load on noninfarcted zones and mixed concentric/eccentric hypertrophy
what medications can slow or reverse cardiac remodeling?
Angiotensin converting enzyme (ACE) inhibitors and some beta blockers can slow or reverse certain parameters of cardiac remodeling
Heart Failure with Systolic Dysfunction results in Increased _____ (e.g., fluid overload) which results in dilation of atria and ventricles with increased diameter (stretch)
preload
in Heart Failure with Systolic Dysfunction, Increasing stretch results in output of what two peptides (ventricles) to increase loss of water and sodium, and to increase vasodilation (reduce preload)?
ANP (atria) and BNP
in Heart Failure with Systolic Dysfunction, Increased mechanical load (e.g., HTN) or end diastolic volume (e.g., volume overload) causes myocyte and ventricular ______ (results in increased cardiac muscle oxygen requirements)
hypertrophy
in Heart Failure with Systolic Dysfunction, there is stretch, ANP and BNP output to try and reduce preload (vasodilation), and increased mechanical load/ end diastolic volume which causes myocyte hypertrophy and ventricular hypertrophy. All of these factors eventually result in what?
Together these factors eventually result in decreased CO
in Heart Failure with Systolic Dysfunction, reduced CO leads to increased ____ activity, restoring CO by increasing contractility and HR
SNS
in Heart Failure with Systolic Dysfunction, a negative cycle is established. what is this cycle?
Negative cycle established: decreased CO results in reduced renal perfusion → increased renin-angiotensin, aldosterone → increased BP with Na+ and water retention, increases ventricular remodeling → further increased preload → further reduction in CO
Heart Failure with ________Dysfunction Results from inability of the ventricle to fully dilate to accept preload, contractility is not affected therefore EF frequently preserved
Diastolic Dysfunction
what two things cause Diastolic Dysfunction in heart failure?
- Mocardial hypertrophy reducing ventricular relaxation and EDV 2. Fibrosis or related changes to cardiac tissue, reducing dispensability / stretch, thereby reducing EDV
Left-Sided Heart Failure is Commonly caused by? (4 things)
- Ischemic heart disease (e.g., post-MI) 2. Hypertension (increased afterload) 3. Aortic (increased afterload) or mitral valve disease (decreased SV due to regurgitant flow during systole) 4. Other non-ischemic myocardial disease (infectious, alcohol, medications, postpartum, chronic tachycardia, ESRD, sarcoidosis, autoimmunity)
Left-Sided Heart Failure Results from increased LV _______?
afterload or increased preload
in Left-Sided Heart Failure, “Backup” of blood in pulmonary circulation results in what?
increased lung circulation pressure, pulmonary edema, shortness of breath, eventual right heart failure
Right-Sided Heart Failure Results from increased RV _____?
increased RV afterload
Right-Sided Heart Failure is Commonly caused by what two things?
- Pulmonary hypertension (results in “cor pulmonale”)–>Only right ventricle involvement 2. Left-sided failure (MCC)
in Right-Sided Heart Failure, “Backup” of blood results in what?
increased systemic and portal venous pressure, peripheral edema
