If you wink at me i'll Wenckebach
Describe the path of blood through the heart to the body (including valves).
1) inferior/superior vena cava –> 2) right atrium –> 3) tricuspid valve –> 4) right ventricle –> 5) pulmonary arteries –> 6) lungs –> 7) pulmonary veins –> 8) left atrium –> 9) mitral or bicuspid valve –> 10) left ventricle –> 11) aortic valve –> 12) aorta –> 13) body.
Name he three layers of arteries and describe them
Adventitia (externa): loss outermost layer
Media: lots of variation here dependent on arterial size and function
Intima: at a minimum this is endothelium with extra cellular matrix on basement membrane, but there is lots of variation.
Distinguish between hyperemia and congestion
Hyperemia: protective process- arterioles dilate to promote blood flow --> this resolves
Congestion: passive process: due to increased pressure in the venous system -->decrease in venous flow. This can resolve but does not always
What are the three mechanisms that cause edema?
1. too much hydrostatic pressure drives fluid into interstium (more than lymphatics can pick up)
2. Not enough fluid is pulled in from the interstitum into post capillary venule because of low oncotic pressure
3. Hydrostatic and oncotic pressure are normal but the lymphatic system cannot pick up what it needs (lymphatic disease)
What are the three abnormalities that lead to thrombus formation?
1. Endothelial injury
2. Stasis
3. Hypercoagulability
Describe the 4 possible outcomes of venous thrombus
1. Resolution
2. Embolize to lungs
3. Incorporation into the venous walls
4. Body can break down clot
What are predisposing factors of fat emboli and explain the pathophysiology?
Crush injuries/ Trauma
Mechanical obstruction to flow and biochemical injury to squamous cell layer (endothelium)
The production of clotting factors are dependent of what?
Bonus: What is the inhibitor of this?
Vitamin K
Coumadin is an inhibitor
What are the mechanisms that contribute to essential hypertension?
impaired sodium excretion, increased vascular resistance, genetic anomalies, socioeconomic and environmental factors
Hypertension (older), connective tissue disease (younger), drug use, iatrogenesis, pregnancy
Describe the classifications of infarcts.
Bonus: what is the most common necrotic finding?
Red: bleeding into the infarct
White: no alternative blood flow
septic: caused by infectious disease
bland: non infectious mechanism
Usually results in ischemic coagulative necrosis; except brain (liquefactive necrosis)
How does right sided heart failure usually develop and what is a common feature?
Right sided HF is usually a consequence of left sided HF
The common feature is pulmonary hypertension which results in hypertrophy and dilation of the right side of the heart
Define an aneurysm and explain the different types
An outward ballooning of a blood vessel or heart due to weakening of one or more layers.
1. True: involves all 3 layers
2. saccular/berry: usually occurs in brain
3. Pseudoaneurysm: defect in intimal/medial layers but held by adventitia
4. fusiform: usually occurs in aorta
What are the three outcomes of pericarditis?
1. resolution
2. Chronic constriction (scarring)
3. Acute onset of pericardial effusion
What are complications associated with an acute MI?
Contractile dysfunction, RV infarct, arrhythmias, chamber dilation, progressive heart failure, ventricular remodeling
What determines the extent of an MI?
1. Size and territorial distribution of vessel
2. rate and duration of occlusion
3. metabolic demands of myocardium
4. extent of collateralization
What are the vessels involved in PAN?
Pulmonary (lungs spared)
Intestines (abd pain, melena)
Nerves (motor)Cardiac
Hepatic
Kidney (worsening HTN)
Define heart failure and distinguish between systolic and diastolic dysfunction
Heart failure is not a primary disease but the end result of many diseases. Heart failure is the inability of the heart to meet the demand of the tissues.
Systolic: pumping problem
Diastolic: filling problem
Describe the relationship between hypertension and left ventricular hypertrophy
Hypertension causes the left side of your heart to pump/work harder than normal. The extra work it takes to pump blood can cause the muscles in the left ventricular wall to get larger and thicker
Describe the general effects of valvular stenosis and regurgitation.
Stenosis: limits gross forward movement, higher pressures are required to maintain the volume of flow
Regurgitation: limits net forward blood flow, valve does not completely close, and blood flows backward through the valve to where it came (dilation of chamber)
describe the underlying causes, pathogenesis, and resulting clinical features of infective endocarditis
Causes: thrombus on valve, underlying valve usually abnormal in some way
Pathophysiology: Abnormal heart valve with turbulent and violent blood flow traumatizing the valves and predisposing it to platelet deposition and fibrin buildup
Clinical features: Bacteremia and sepsis of unknown etiology, fever, hematuria, new heart murmur, periphreal abscess, Roths spots
describe the underlying causes, pathogenesis, and resulting clinical features of rheumatic valvular disease
Causes: seems to be genetic
Pathogenesis: Left atrium must generate more pressure to get same amount of blood across the narrowed MV --> more blood left over left atrium dilates --> left arterial pressure back to pulmonary vein into pulmonary vasculature leading to pulmonary hypertension
Clinical features: exertional dyspnea, PND/chronic cough, Afib, atrial thrombus
Define cor pulmonale and identify possible causes
Cor pulmonale: isolated right ventricular failure not caused by left sided hear failure but rather a pulmonary problem
Causes: COPD, interstitial restrictive disease, chronic lung infections, PE, pulmonary hypertension
What are the 6 major pathophysiologic mechanisms of cardiac dysfunction?
1. Pump failure (diastolic/systolic)
2. Obstruction to flow (increase afterload)
3. Regurgitant flow (increase to preload)
4. Shunted flow (diversion of flow)
5. Conduction (electrical problem)
6. Rupture (chamber or vessels)
List the three major categories of shock and describe their underlying pathogenic mechanisms
Cardiogenic: failure of myocardial pump resulting from intrinsic myocardial damage, extrinsic pressure or obstruction to outflow
Hypovolemic: inadequate blood or plasma volume
septic: periphreal vasodilation and pooling of blood, endothelial activation/injury/, leukocyte induced damage, activation cytokines