Cardio Flashcards
Complications from Artherosclerosis
TEA (and) PII Thrombosis Embolism Aneurysm Peripheral Vascular Disease Ischemia Infarction
Arteries effected by Atherosclerosis
AA > Coronary Arteries > Popliteal Artery > Carotid Artery
Causes of cardiogenic shock
Acute MI, HF, valvular dysfunction
Increased EDV, increase Afterload, decreased CO
Causes of obstructive shock
PE, tamponade
(Increased Preload (or decreased preload for tamponade or constrictive pericarditis) , increased afterload, decreased CO)
Causes of hypovolemic shock
hemorrhage, burn, GI bleed
Decreased preload, increased afterload, decreased CO
Causes of distributive shock
Sepsis, CNS injury, anaphylaxis
decreased preload, decreased afterload, increased CO
Early and late signs of shock
Tachycardia –> multiple organ failure
What is the vessel change in response to HT?
increase in media thickness with a relative decrease in lumen size
(arteriolosclerosis is a hypertensive change to arterioles)
What is the vessel change in atherosclerosis?
Intimal thickening (sub-endothelial matrix) due to inflammatory rxn to deposition of oxidized LDL Atherosclerosis can be conceptualized as chronic inflammation
Pathogenesis/Pathway of HT
Initial increase in CO (not well understood) –> increase in BP –> Ateriole Wall stress –> Hypertrophy of media –> decreased lumen size –> increase PVR –> increased BP (CO returns to normal)
What is primary HT characterized by?
Structural changes in small arteries (SMASCH- small artery structural changes)
Angiotensin II role in primary HT
- ) Increases endothelial permeability (albumin leak, hyaline change)
- ) Increases VSMC calcification (monkeburg)
- ) Vasoconstriction (decrease NO, lumen narrowing)
- ) Smooth muscle expansion (medial hypertrophy, hyperplastic change)
- ) Matrix deposion, MMP action (reason for hyperplastic change, remodeling)
Role of Ang II in atherosclerosis
- ) Increases platelet aggregation (PA1 and PA2 receptors)
- ) increase expression of VCAM 1 and inflammatory cytokines (brings leukocytes in and bind)
- ) Decrease NADPH oxidase, increase ROS
Hypertensive Injury
- LVH
- CKD- grossly kidneys shrink and become granular
- CVA: charcot /leticulostriate arteries of bg; dilation and rupture due to HT
- Hypertensive retinopathy
What is the function of cholesterol in the body?
- Membrane fluidity
- Steroid hormones
- Vit D
- Bile salts
How does turbulent flow effect artherosclerotisis development?
Creates areas of high and flow shear stress, areas of low shear stress respond by trying to balance/increase shear stress by increasing subendothelial proteoglycans which bind LDL (body trying to equalize pressure to what it thinks are hypotension)
- Shear stress also increases inflammatory response by provoking transcription of inflammatory cytokines and decreasing NO synthase (vasoconstriction and inflammation)
- Get more LDL and more ROS = more oxidized LDL
Why do macrophages bind oxidized LDL?
Oxidized LDL mimics malaria infected erythrocytes, TB bacterium, and strep pneumo
Savenger receptors (CD36) on macrophages recognize these PAMPs and are activated
Macrophages release substances that induce a chronic inflammatory response
Phagocytose LDL –> foam cells –> decrease migration, increase lipid uptake, increase ROS genereation
How do LDL particles get oxidized?
- Extravascular reduced antioxidant exposure
- Smoking
- Diabetes
- Aging (leaky ox phos enzymes)
- Inflammatory response
How do you get a necrotic core in atheroma formation?
Foam cells have ER stress which provokes apoptosis, enough of them undergoing apoptosis that efferocytosis (reabsorption of apoptotic cells), is diminished
Primary cause of hypertrophic cardiomyopathy
Missence ; AD mutation with uneven pentrance of beta myosin chain
Over 400 mutations but all associated with sarcomere proteins
Increase myofilament activation
What part of the heart is most hypertrophic in HCM
ventricular septum
Bananna like config
What is arrythrogenic right ventricular cardiomyopathy?
AD disorder of cardiac muscle where the myocardium is replaced by fatty infiltrate and moderate fibrosis
Desmosomal junction mutations
Type of DCM
What is LV non compression cardiomyopathy
Congenital disorder that causes spongy ventricles
What populations is HCM associated with?
athletes under 35 (exertion = death)
Friedrisch ataxia patients
What are the three primary types of restrictive cardiomyopathy?
- Amylodosis
- Endomyocardial fibrosis
- Loeffler endomyocarditis
What type of amylodosis do you see in heart disease?
- systemic (beta pleated sheets)- primary (AL) or secondary (AA)
- senile cardiac amyloidosis (transthyretin- thyroxine and retinol transporter made in liver; found in older people and 4% of Af Am have gene mutations in transthryetin that predisposes)
Who gets endomyocardial fibrosis?
Children and young adults in Africa and other tropical areas
Dense diffuse fibrosis of endocardium and subendocardium that often effects M and T valves
Thought to be related to nutrational deficiency and helmith infection related inflammation
Most common cause of restrictive endocarditis globally
What is Loeffler endomyocarditis?
Large mural thrombi in all areas of the heart with peripheral and tissue infiltrates of eiosinophils (thought to release MBP which causes necrosis followed by layering of endocardium with thrombus)
Some people have PDGFR tyrosine kinase mutations and can reverse disease with tk inhibitors
What are the primary causes of myocarditis?
- Viral (Cocksackie A and B- majority, CMV, HIV, influenza), often damage caused by immune response
- Non viral- Chagas (trypanasoma cruzi) toxoplasma, trichinosis, lyme disease
- Noninfectious: antibody mediated (SLE, drug rxns)
What are common causes of pericarditis?
Not often primary (Viral)
Secondary to MI, cardiac surgery, radiation, pneumonia, pleuritis, uremia, (less commonly RF, SLE, Mets)
What type of cancer is most common in the heart?
Mets
Lung cancer> lymphoma > breast> leukemia >melanoma>hepatocellular carcinoma > colon cancer
80-90% of primary heart tumors are _______?
benign