Cardiomyopathies Flashcards
what is the endocardium
innermost layer of the heart muscle
both endothelium and CT - has protective anti-thrombic properties
contiguous with vasculature and covers valvular structures
what makes up the myocardium
striated cardiac muscle - oriented in a twisted formation for best squeeze and CO
what layer of the heart is made up of the visceral layer of the pericardium
epicardium
what layer are the coronaries underneath
the epicardium
What is the cardiac output
heart rate x stroke volume
what is the stroke volume
the amount of blood ejected from each ventricle with each contraction
usually about 70ml
what is the average Cardiac output
4000-5000mL
what is the preload
the venous return
what affects the stroke volume
venous return (preload)
blood volume
SNS (contractility)
Peripheral resistance (afterload)
what are factors that increase HR
SNS (norepi and epi)
increased thyroid
hypoxemia and acidosis
medications
What factors decrease HR
Parasympathetic (ach)
Medications
Athletes
What is ESV
end systolic volume
how much is left over after contraction
typically = 50mL
What is EDV
end diastolic volume
amount in ventricle right before contraction
typically = 120mL
What is the Ejection fraction equation
stroke volume / EDV
what increases in relation to the preload
ventricular output
what determines how much a myocyte can retract back to normal length, if this load is elevated, it will not be able to shorten adequately
afterload
what is the frank-starling curve
represents the relationship between stroke volume and end diastolic volume.
states that the stroke volume of the heart increases in response to an increase in the volume of blood in the ventricles, before contraction, when all other factors remain constant.
what is cardiomyopathy
disease process that changes the cardiac structure that affects the myocardium itself
m/c referencing disease process of the LV
what is impaired with cardiomyopathy
cardiac function and may also alter the cardiac electrical conduction
what are cardiomyopathies broken down into
hypertrophic
dilated (M/c)
arrhythmogenic
restrictive (least common)
unclassified
(genetic, mixed, acquired)
what are genetic cardiomyopathies
hypertrophic cardiomyopathy
arrhythmogenic cardiomyopathy
Left ventricular noncompaction
conduction defects
mitochondrial myopathies
ion channel disorders
what are acquired cardiomyopathies
takotsubo
myocarditis
peripartum
tachycardia induce
what are mixed cardiomyopathies
dilated cardiomyopathies
restrictive cardiomyopathies
What is MOGES classifcation
classification system gives information about the disease but also may be able to help risk stratify pts for potential future cardiovascular events
M: morphofunctional
O: Organ involvement
G: genetic predisposition
E: Etiological definition
S: functional status
decreased contractility leading to reduced ejection fraction is caused by
systolic dysfunction
what is systolic dysfunction
decreased contractility leading to reduced ejection fraction
causes: dilated cardiomyopathy
the inability for the ventricle to completely relax to allow for appropriate passive filling is caused by
diastolic dysfunction
what is disastolic dysfunction
inability for the ventricle to completely relax to allow for appropriate passive filling
what are the causes of diastolic dysfunction
hypertrophic cardiomyopathy
restrictive cardiomyopathy
what is the most common cardiomyopathy
dilated cardiomyopathy
what is associated with an increase in filling volume
dilated cardiomyopathy
what is increased with dilated cardiomyopathy
increased preload (EDV)
will cause increased atrial pressure
atrial dilation
what is the most common cause of right sided heart failure
left sided heart failure
what is activated within the body to increase the BP
renin-angiotensin-aldosterone system which is activated by decreased CO
What is transient ballooning of the cardiac apex due to profound stress
Takotsubo - “broken heart”
classically seen in postmenopausal women
what is thought to be associated with a huge catecholamine surge, microvascular dysfunction and spasm of the coronaries
Takotsubo
what is the presentation of dilated cardiomyopathy
symptoms of left sided heart failure
S3 sounds
dilation can change annulus
can present with arrhythmia
may see right sided HF depending on severity
what is the presentation of left sided heart failure
pulmonary concerns - pulmonary edema
what is the presentation of right sided heart failure
more edema and ascites
fatigue, increased peripheral venous pressure
distended jugular veins, Anorexia & GI distress
weight gain
what is hypertrophic cardiomyopathy
thickened myocardium leading to poor diastolic filling
may lead to outflow obstruction
what can cause hypertrophic cardiomyopathy
genetics: inherited (autosomal dominant) or mutations
chronic HTN
Aortic stenosis
amyloidosis
what presents with a more pronounced septum
hypertrophic cardiomyopathies
What is HOCM
Hypertrophic Obstructive Cardiomyopathy
- often causes sudden cardiac death in athletes
occlusion of the outflow tract (aortic valve) which causes a vacuum with mitral valve and decreases CO
what is the presentation of hypertrophic cardiomyopathy
systolic murmur
S4 heart sounds
HF
Arrhythmia
may also have findings of mitral regurgitation
What is restrictive cardiomyopathy
fibrosis of the myocardium
infiltrative disease - decreased compliance
what is the pathophysiology of restrictive cardiomyopathy
fibrotic changes within the myocardium which decreases compliance of the ventricles
this decreases ventricular filling capacity
what can restrictive cardiomyopathy lead to
diastolic dysfunction
RV HF and LV HF secondary to decreased compliance
systolic murmur
what are the causes of restrictive cardiomyopathy
endomyocardial fibrosis
radiation fibrosis: secondary to radiation to the mediastinum
amyloidosis
sarcoidosis
hemochromatosis
What is endomyocardial fibrosis
autoimmune issue marked by eosinophilia which is an inflammatory reaction and fibrosis of the endocardial surfaces
who are endomyocardial fibrosis most common in
children of developing countries
What is amyloidosis
misfolded antibodies which are able to be deposited within the tissues
- genetic cause
leads to fibril deposition
deposition within the tissues - chronic inflammation
What is sarcoidosis
autoimmune disease - exact pathophysiology not completely understood
hallmarked by non-caseating granuloma formation
deposits within heart, joints, eyes, skin, lungs
what is the granuloma in sarcoidosis made up of
macrophages and fibrotic tissues, centrally contains epitheloid cells
what is hemochromatosis
excess iron due to poor protein modulation within the liver
leads to increased absorption and release from the sleep
iron deposits within the myocardium
