ICL 5.0: Pathology of Myocardial Diseases and Congestive Heart Failure Flashcards
what is congestive heart failure?
a mechanical failure of the heart to maintain systemic perfusion commensurate with the requirements of metabolizing tissues
the heart can’t pump enough blood to properly perfuse tissues and organs
what can lead to heart failure?
- pump fialure
- disease of myocardium
- regurgitant flow
- obstruction to flow
- conduction disorders (arrhythmias)
- disruption of circulation system (shock)
what is forward CHF?
pump is failing and blood can’t be pumped out?
what is backwards CHF?
diastolic dysfunction where the blood can’t be pooled in the heart properly
65 year old male goes to his PCP complaining of dyspnea on exertion and severe dyspnea when he lies down at night to the point that he needs to prop himself up on three pillows to feel comfortable. He has been hypertensive for 6 years he often forgets to take his medication
diagnosis?
- dyspnea when lying down = increased venous return = increased preload
- HTN for 6 years = compromised heart
- presenting with symptoms of CHF
left sided CHF
what are the causes of left sided CHF?
- ischemic heart idsease
- HTN
- aortic and mitral valve diseases
- myocardial diseases
what is the clinical presentation of LCHF?
- dyspnea
- orthopnea
- paroxysmal nocturnal dyspnea
what is the morphology of LCHF?
- hypertrophy of the heart–> he’s pumping against increased peripheral resistance
- congestion and edema of the lungs = crackles on PE
heart failure cells = when you have severe congestion capillaries break down and RBCs are released in alveoli and then Hb breakdowns into hemocydrin once the RBCs die and alveolar macrophages phagocytose the hemocydrin –> heart failure cells are alveolar macrophages with hemocydrin pigment
what happens to the kidney in LCHF?
decreased renal perfusion –> activation of RAAS –> retention of salt and H2O, increased blood voluem
what happens to the brain in LCHF?
hypoxic encephalopathy
what are the 2 classes of LCHF?
- systolic failure
2. diastolic failure
what is systolic left sided CHF? what causes it?
pump failure
caused by ischemic diseases and valvular diseases
what is diastolic left sided CHF? what causes it?
stiff left ventricle that doesn’t relax during diastole and leads to defective filling
caused by amyloidosis, fibrosis and sever hypertrophy
65 year old female with a history of chronic bronchitis for the last 10 years presents to the emergency room with shortness of breath and pedal edema
CHF secondary to lung failure
this is ride-sided CHF!
what is right sided CHF?
usually the result of left-sided failure
or it can be a pure-rigth sided failure secondary to increased pulmonary pressure = cor pulmonale –> blood is not drained properly from the periphery so there’s liver congestion
what are the effects of right-sided CHF on the liver
blood is not drained properly from the periphery so there’s liver congestion
this can cause liver congestion which can escalate to cardiac sclerosis or cardiac cirrhosis
congestion of the sinusoids can put pressure on the surrounded hepatocytes which can become necrotic and their membrane becomes leaky and LDH5 enzymes leak out!
what part of the body are the various LDH enzymes found in?
LDH1 = heart and RBC –> increased after MI
LDH3 is from the lung
LDH 5 is from the liver
LDH 2 and 4 aren’t specific
what are the effects of RCHF on other parts of the body?
- liver congestion
- congestive splenomegaly
- pleural effusion
- ascites
- peripheral edema
- brain congestion and edema
which lab values indicate CHF?
BNP = B-type natriuretic peptide
BNP regulates BP and mainly comes from the heart
it’s released in the blood in response to increased heart pressure
increased BNP indicates CHF!!
0-100 pg/mL is normal and anything higher indicates CHF
what are the clinical signs of left sided CHF?
- hypoxia
- orthopnia
- dyspnea
what are the clinical signs of right sided cHF?
- edema
2. elevated jugular venous pressure
what are heart failure cells?
heart failure cells are alveolar macrophages with hemocydrin pigment
what are cardiomyopathies?
heart muscle diseases of unknown causes
there are dilated, hypertrophic and restrictive cardiomyopathies
they’re diagnosed by cardiac biopsy
what causes dilated cardiomyopathy?
- alcohol
- peripartum
- genetic
- myocarditis (coxsackie virus)
- adriamycin toxicity = chemotherapy
how does alcohol cause dilated cardiomyopathy?
aka beer heart!
we aren’t sure what the mechanism is: either thiamine deficiency or direct toxicity
what is peripartum dilated cardiomyopathy?
occurs in pregnant women in the 3rd trimester
there are increased levels of an antiangiogenic cleavage product of prolactin
it’s either nutritional or immunologic cause
what is genetic dilated cardiomyopathy?
due to a mutation of the dystrophin gene!
dystrophin is a cytoskeletal protein that plays a critical role linking internal cytoskeleton with the external basement membrane
it can also sometimes be caused by mutations in alpha cardiac actin that links the sarcomere with dystrophin
what age group is effected by dilated cardiomyopathy?
20-50 years old
patients will present with heart failure
what is dilated cardiomyopathy?
progressive cardiac dilation and contractile systolic dysfunction
what is the gross and microscopic morphological changes seen in dilated cardiomyopathy?
- heavy and flabby heart
- dilated chambers
- thin walls
- microscopically there are large myocardial fibers with fibrosis
what are the complications of dilated cardiomyopathy?
- arrhythmias
- embolisms
flabby and dilated heart can’t empty properly so it stagnates and clots
13 year old girl collapses after a volley ball game and in spite of efforts to resuscitate her she dies. Family history cousin died suddenly at age 15.
diagnosis?
hypertrophic cardiomyopathy
young person, family history
what is hypertrophic cardiomyopathy?
an idiopathic hypertrophic subaortic stenosis
that means it is going to be obstructive to the heart flow because the septum of the heart under th aortic valve is the one that becomes the most hypertrophic so you have obstruction of the blood flow
what is the genetic cause of hypertrophic cardiomyopathy?**
a missense mutation in the genes encoding:
- B myosin heavy chain
- cardiac troponin T, tropomyosin and and myosin binding protein (MYBPC)
what is the gross and microscopic morphological changes seen in hypertrophic cardiomyopathy?
- thick heavy heart
- hypercotracting = no dilation
- disproportionate thickening of the septum
- diastolic dysfunction
- microscopic hypertrophy with huge fibers/nuclei in a fibrous disarray
what is the clinical presentation of hypertrophic cardiomyopathy?
- impaired diastolic filling
2. harsh systolic ejection murmur
summary of dilated cardiomyopathy?
caused by alcohol, postpartum, coxasackie, chemotherapy and dystrophin mutation
morphologically you see hypertrophy with fibrosis
summary of hypertrophic cardiomyopathy?
caused by B myosin heavy chain and troponin T
morphologically you see hypertrophy with myofiber disarray
A 70 year old female presents to have her PCP with congestive heart failure, with Pedal Edema. severe back
BP 120/75
UA 4+protein (high)
Serum protein 8 (high)
Albumin 3.5 (normal)
Serum electrophoresis M spike
Monoclonal Kappa Light chain
DD:
Test:
Final Diagnosis:
multiple myeloma
high immunoglobulin with an M spike and monoclonal kappa light chain
amyloidosis is often associated with multiple myeloma –> amyloidosis of the heart is restrictive because it infiltrates the myocardium and it becomes stiff and during diastole it can’t relax and you have diastolic failure
what are the different types of amyloidosis?
- senile
- familial
- multiple myeloma
- restrictive cardiomyopathy
what are the causes of restrictive cardiomyopathy?
- iron overload (hemochromatosis)
- hyperthyroidism
- hypothyroidism
- amyloidosis
what is cor pulmonale?
right ventricular enlargement resulting from structural or functional lung disorders
what are the two types of cor pulmonale? what can cause each type?
- acute
following massive PE
- chronic
ex. COPD, fibrosis, pulmonary vessel disease, pulmonary HTN , hypohsosi, scoliosis, hypoxia
what is hypertensive heart disease?
left ventricular hypertrophy in absence of cardiovascular pathology = no fibrosis, cardiopathy or myopathy
they just have HTN and this causes the heart to get really big
what is the pathogenesis of hypertensive heart disease?
increase BP is a risk factor for atherosclerosis which leads to large vessel decreased compliance and thickening of the small arteries and arterioles = increased peripheral resistance
this makes the heart pump against more pressure so it hypertrophies and since it’s bigger it now needs more oxygen to survive so then it fails
so hypertensive heart disease leads to heart failure!!
what are the morphological changes seen in hypertensive heart disease?
- gross hypertrophy
2. microscopic hypertrophy and large rectangular nuclei
what is myocarditis?
inflammation of the myocardium
it’s a cause of dilated cardiomyopathy!!
A 35 year old male presents to the emergency room in acute congestive heart failure he has a history of fever 102° and malaise for three days prior to the ER visit.
DD:
Tests:
Final DX:
viral myocarditis
what are the major infectious causes of myocarditis?*
- coxsackievirus (virus)
- Lyme disease (bacteria)
- Chagas (protozoa)
- COVID
which immune mediated reactions can cause myocarditis?*
- post-streptococcal = rheumatic fever
2. transplant rejection
what is the clinical presentation of myocarditis?
- asymptomatic
- fever, malaise
- pericardial pain = sharp
- sudden onset of acute heart failure
what are the morphological changes seen with myocarditis?
- dilated ventricles
- flabby heart
- minute hemorrhages
- mural thrombi may be present
- necrosis of myocytes
- lymphocyte infiltrates** (this is ONLY in myocarditis and transplant rejection)
think of dilated cardiomyopathy!
65 year old male receiving Doxorubicin for colon cancer presents to ER with dyspnea, pulmonary crackles, and pedal edema. His BNP is 1000 Echo reveals decreased EF and a dilated heart.
DD:
Morphology:
dilated cardiomyopathy secondary to the drug
which cardiotoxic drugs can cause dilated cardiomyopathy?
- doxorubicin
causes lipid per oxidation in myocytes
- anthracyclin
- lithium
- chloroquine
sometimes there’s permanent change even with drug cessation ):
how do cardiotoxic drugs cause dilated cardiomyopathy?**
- myofiber swilling
- cytoplasmic vacuolization**
- fatty change
