Chapter 24 - Alteration In CV Function Flashcards
Varicose veins
Veins where blood has pooled producing distended and palpable vessels
Cause of Varicose veins
Trauma that damages valves or gradual distension caused by action of gravity
Valve damage due to
Increase pressure and volume of blood under pressure of gravity
Varicose veins typically involve what veins of the leg
Saphenous veins of legs
Pathophysiology of varicose veins
Enzymes remodel vessel wall, and veins swells with increased pressure and pressure pushes plasma through vessel wall
Risk factors for varicose veins
-standing for long periods which diminishes action of muscle pump
-age, obesity, genetics, pregnancy, previous leg injury
Varicose vein TX
-elevated legs, compression stockings
Invasive TX: surgical ligation -> tying up blood vessel
Chronic venous insufficiency
Inadequate venous return over ext3ended period
Symptoms of Chronic venous insufficiency
-edema of lower extremities
-hyperpigmentation of ankle and feet skin
-circulation sluggish, reduced oxygen to cells causing necrosis
-surgery
Venous statis ulcers
Infection occurs because of poor circulation in veins and impairs delivery of oxygen causing necrosis
Thrombus
Blood clot that remains attached to vessel wall
Thromboembolism
A detachedthrombus
Venous thrombi are more common than
Arterial thrombi as flow and pressure are lower in veins
-also occurs more often in lower extremity
The virchow triad
Three factors that promote deep venous thrombosis
1. Venous stasis (immboity, age, heart failure)
2. Venous endothelial damage
3. Hypercoagulable states (inc tendency of blood to thromboses)
Hypercoagulable states are caused by
Pregnancy, oral contraceptives, heredity
Pathophysiology of thrombus formation in veins
-Accumulation of clotting factors and platelets near a venous valve cause venous obstruction
-inflammation promote further planet aggregation causing pain and redness
Thrombus obstruction creates extremity edema causing
Ulceration of limb (break on surface)
TX for thrombus formation in veins
Most thrombus dissolve without treatment
-anticoagulants (aspirin, warfarin)
Diagnosis for thrombus formation in veins
Doppler ultrasonography
Doppler ultrasonography
Non invasive test that can be used to estimate blood flow through blood vessels by bouncing high frequency sound waves
Superior vena cava syndrome
Progressive occlusion of Superior vena cava leading to venous distension to upper extremities and head
Causes for Superior vena cava syndrome
Bronchogenic cancer
-75% of cases
-ontological emergency
Pathophysiology of Superior vena cava syndrome
Lung bronchi abuts Superior vena cava syndrome = bronchi cancer puts pressure on SRV
Result of Superior vena cava syndrome
Edema and venous distension in upper extremities and face
Effect of Superior vena cava syndrome
Tightness of shirt collars, necklaces, headache, visual disturbances
Diagnosis of Superior vena cava syndrome
Chest, X-ray, CT, MRI
Hypertension
Consistent elevation of systemic arterial blood pressure
Risk of hypertension
Increases with age, higher in diabetes
Maintenance of proper BP
Exercise and proper nutrition
Percentage of primary hypertension vs secondary hypertension
95% of cases and 5% of cases
Malignant hypertension
Rapidly progressive hypertension
S: >180, D: >120
-system and organ complications, can be considered a medical emergency
Normal BP
Less than 120/less than 80
Elevated BP
120-129/less than 80
High blood pressure (stage 1)
130-139/80-89
High blood pressure stage 2
140+/90+
Hypertensive crisis
180+/120+
Factors associated with primary hypertension
No specific cause
-genetic and environmental factors
-epigenetic changes
Epigentic
How behaviours and environment affect gene function
Hypertension results form
Sustained inc in peripheral resistance, inc in blood volume
Two primary factors of primary hypertension
- Sympathetic ns
- RAAS
SNS and primary hypertension
Inc SNS will cause INC HR, cardiac contractility, systemic vasoconstriction = rise in BP
RAAS
Renin angiotesin, angiotesnin II, aldosterone pathways
RAAS increases in (aldosterone vs angiotensin II)
- Aldosterone = inc Na reabsorption from kidney, inc blood volume, inc BP
- Angiotensin II = inc vasopressin which inc vasoconstriction and inc BP
Arteriosclerosis
A: Genetic term for vascular disease in which causes thickening an inelasticity of arteries
S: hardening of body tissue
Atherosclerosis
Dominant pattern of arteriosclerosis
-formation of fatty plague with core rich in lipids
Athero
From Greek word athera meaning porridge
TX for hypertension
Begin with lifestyle modifications: diet, exercise, stopping, smoking, loosing weight
Advanced: diuretics, angiotensin II blockers
What is orthostatic hypotension
Decrease in systolic BP of 20 mmHg or a decrease in diastolic BP of 10 mmHg within three minutes of standing
-mechanical dysfunction
Normally what happens during standing
Baroreceptors, vasoconstriction and heart rate adjusts to maintain normal BP
Signs and symptoms of orthostatic hypotension
Dizziness, loss of vision, reduced brain blood flow
Treatment for othrostatic hypotension
No curative treatment
-inc fluid and salt intake, wearing thigh high stockings
Aneurysm
Localized dilation of vessel wall
What layers of the arterial wall does an Aneurysm involve
All three layers, causing weakening
What is the most common site of an Aneurysm
Aorta
-constant high pressure stress
Risk factors of Aneurysm
Smoking, genetics, diet
What are the three CV vessel layers
Tunica adventitia, tunica media, tunica intima
Embolism
Vessel obstruction by an embolus (bolus of matter circulating in blood stream)
An embolism consists of
A dislodged thrombus, aggregating of fat or cancer cells, and foreign substances
Embolus travels in blood stream until it reaches
A vessel through which it can’t pass
Embolism causes
Ischemia (restricted blood supply)
-continual obstruction can cause infarction (ischmeia resulting in necrosis)
Thromboangiitis obliterans (buergers disease)
Inflammation of peripheral artery
-strongly associated with smoking
-autoimmune disease
How is Thromboangiitis obliterans (buergers disease), an autoimmune disease
Thrombus is filled with immune cells, causing an occlusion of smaller arteries
S/s of Thromboangiitis obliterans (buergers disease)
Symptoms: pain and tenderness in affected area
Signs: reddish skin, thickened and malformed nails
TX for Thromboangiitis obliterans (buergers disease)
Stopping smoking
-if you don’t stop amputation is likely required
Atherosclerosis
Formation of fatty plague with a core rich in lipid
What is the leading cause of CAD
Atherosclerosis
Atherosclerosis is caused by
Smoking, hypertension, diabetes, inc LDL, dec HDL, autoimmune
Pathophysiology of Atherosclerosis
Begins with injury to epithelial cells lining artery wall
-injured cells become inflamed
-inflamed cells express adhesions molecules that bind macrophages
-bound macrophages releases cytokines damaging vessel wall
-cause free radicals to oxidize LDL
-macrophages engulf oxidized LDL
-macrophages are now considered foam cell
-foam cells accumulatte and form fatty streak
-fatty streak results in recruitment of T cells
-macrophages release growth factors producing collagen
-collagen accumulates over fatty streak forming a fibrous plague
-fibrous plague protrudes into lumen and obstructs blood flow
-this fibrous plague may rupture (complicated plagues)
-producing rapid thrombus formation
-ishcemia or infarction
How does Atherosclerosis being?
Injury to epithelial cell lining artery wall
Inflammation caused free radicals to do what?
Oxidize LDL
Foam cell
Macrophages that have engulfed oxidized LDL
-form fatty streak
Fatty streak results in
Recruitment of T cells
-more damaged to vessel wall
Fibrous plague
Collagen accumulation from growth factors
-obstructs and occludes blood flow
Complicated plagues
Fibrous plagues that have ruptures
-rapid thrombus formation
Coronary heart disease is usually caused by
Atherosclerosis
-plague build up diminishing blood supply to cardiac muscle cells
Results of Coronary heart disease
Myocardial ischemia and infarction deprives heart muscle of blood borne oxygen and nutrients
-impairs heart pumping ability
Myocardial cells remain ___ but are not
Alive, not functioning properly
Persistent ischemia caused
Acute coronary syndromes
-including myocardial infarction
Infarction potentially triggers a
Heart attack
Cardiac infarction
Obstruction of blood supply causing irreversible myocardial damage
Dyslipidemia has a link between
Abnormal lipoprotein levels and CAD
Lipoproteins
High density lipoproteins (HDL) and low density lipoproteins (LDL)
What is responsible for delivery of cholesterol to tissues?
LDL
What is responsible for delivery of excess cholesterol back to liver?
HDL
LDL
High intake of cholesterol and saturated fats will elevate levels
-can cause LDL migration into vessel walls = atherosclerosis
HDL
Plays a role in endothelial repair and decreases thrombosis
-elevated levels of HDL has not proven to prevent CV disease
What is responsible for 2-3 fold inc in CAD risk
Hypertension
Hypertension causes
Endothelial injury, myocardial hypertrophy which inc heart oxygen demand
Why is cigarette smoking a risk for CAD
-free radical generation
-nicotine simulates catecholamines and inc HR, BP and vasoconstriction
-inc LDL, Dec HDL
Why is obesity a risk for CAD
Abdominal obesity
-inflammation and Dec HDL
-strongest risk of CAD
Why is sedentary lifestyle a risk for CAD
Not only inc risk of obesity but on its own inc risk of CAD
Why is a Atherogenic diet a risk for CAD
Western style diet
-promotes fatty plagues in arteries
Diet most recommended for health
Mediterranean diet
Hs-CRP test
High sensitivity C reactive protein test
-can detect very low levels of C reactive protein
-measures general levels of inflammation in body
Elevated serum hs-CRP is correlated to
Increased CAD risk
CRP
Protein synthesized in liver in response to inc in inflammation in body
Hs-CRP test is used to determine
Heart disease risk and stroke in people without known heart disease
Hs-CRP value: <1 mg/L
Low risk
Hs-CRP value: 1-3mg/L
Average risk
Hs-CRP value: >3 mg/L
High risk
Adipokines
Hormones released from adipose cells, two of which are lepton and adiponectin
Obesity =
-inc inflammation
-inc leptin
-Dec adiponectin
Adiponectin
Protects vascular endothelium and is ant-inflammatory
Myocardial ischemia develops when
Blood borne oxygen is insufficient to meet myocardial metabolic demands
Common cause of myocardial ischemia
Atherosclerosis in coronary circulation, causing plague rupture = thrombus formation, occlusion and myocardial ischemia
Myocardial cells become ischemia within ___ seconds of occlusion
10
Shifts toward anaerobic causes
Lactic acid accumulation, decreased rate of ATP re-phosphorylation
After several minutes
Heart loses ability to contract
If perfusion is not restored…
Myocardial infarction occurs within 20 minutes
Angina
Chest pain caused by myocardial ischemia
Stable angina pectoris
Gradual narrowing and hardening of arterial walls associated with inflammation and decreased endothelial vasodilators
Stable angina pectoris: affected vessels
Cannot respond to inc myocardial demand during exercise or emotional stress
-causing angina
Stable angina pectoris: angina decreases with
Rest and nitrates
Prinzmetals angina
Transient angina that occurs unpredictably and often at rest/sleep
Cause of Prinzmetals angina
Vasospasm risk of cardiac event
Silent ischemia
Occurs alone or with angina
-inc risk of cardiac event
Abnormal symptoms of Silent ischemia
Fatigue, dyspnea (bad breathing)
Evaluation for myocardial ischemia
Physical examination displays rapid pulse and extra heart sounds
Pulmonary congestion indicates impaired
Left ventricle function
Single photon emission computed tomography (SPECT) is the most
Effective tool
TX for myocardial ischemia
Diet and exercise
-surgery in coronary vessels dilated and placement of coronary stent
harbinger
Impending infarction
-Announces the coming of something
Unstable angina: acute attack signals
Atherosclerotic plague has become unstable, and infarction may soon follow
Unstable angina: superficial erosion of plague leads to
Transient episodes of thrombotic occlusion and vasoconstriction
-occlusions lasts no more than 10-20 minutes
Unstable angina: distinct symptom
Prinzmetal angina increasing in severity
Diagnosis of Unstable angina
-ECG during attack = ST depression, T wave inversion, ST segment elevation
-hs-cTnt = high sensitivity cardiac troponin T can identify tiny amounts of enzymes released from damaged myocytes
TX for Unstable angina
Immediate hospitalization
Clinically, MI is categorized as
Non-stemi or stemi
Unstable angina
Coronary thrombosis leads to myocardial ischemia
NON STEMI
Persistent occlusion leads to infarction of myocardium closest to endocardium
STEMI
Continued occlusion leads to infarction from endocardium to pericardium
Oxygen depletion in 10 seconds then…
After 10 seconds affected myocardium becomes cyanotic and cooler
Aerobic metabolism stops and
ATP generation stops due to anaerobic metabolism
-causes H+ and lactic acid to accumulate
-reduced ATP
Electrolyte disturbances
Loss of K and calcium from cells
-myocardial cells lose contractiability
-diminished ability of heart to contact
Infiltration of immune cells causes
Further tissue damage
Cardiac cells can withstand ischemia conditions for
20 minutes before irreversible damage `
Manifestations of myocardial infarction
Acute, severe chest pain
Diagnosis of myocardial infarction
Hs-cTnT
Photo on slide 20
Heart failure
Inadequate perfusion of tissues or inc diastolic filing pressure of left ventricle
-or both in which pulmonary capillary pressures are increased
Special thing to remember about heart failure
Left ventricle dysfunction will play back to pulmonary problems
Heart failure affects ___ of individuals older than 65 yoa
10%
Most common reason for hospital admission in >65 YOA
Heart failure
Most HF causes are due to
Dysfunction of left ventricle
Left ventricular failure with reduced ejection factor
Left ventricle election fraction less than 40% normal which results in inability of heart to perfuse tissue
CO =
SV x HR
Determinants of SV
Contractility, preload, afterload
Ventricular remodeling
Disruption of normal myocardial function
Ventricular remodeling results in
Dilation of left ventricle
Cause of ventricular remodeling
Progressive myocyte contractile dysfunction
Result of myocyte contractile dysfunction
Reduced stroke volume
-left ventricle end diastolic volume increases
Main causes of myocardial dysfunction
- Myocardial infarction
- Ischemic heart diseases
- Hypertension
Decreased cardiac output and decreased systemic blood pressure =
Reduced perfusion of tissues
Results of reduced perfusion of tissues
Increased sympathetic activit
Causing:
-inc secretion of catecholamines
-inc vasoconstriction
Decreased perfusion of kidneys results in
RAAS activation and increased vasoconstriction and blood volume
Overall result of Left ventricular failure with reduced ejection factor
-inc cardiac afterload
-inc bp
-inc hr
-ventricular remodeling
Ventricular remodeling causes
Progressive myocyte remodeling over time
-dysfunction
Decreased myocyte function =
Decreased contractility which results in increased preload
Effects of increased preload
-stretching of myocardium and sarcomere dysfunction
-further dysfunction in myocardial function
Effects of increased afterload
results of systemic hypertension
-vasoconstriction and inc blood volume
___% of HF cases have previous hypertension
75
Increased afterload =
Myocardial hypertrophy
-myocardial remodeling
Hypertrophy =
Inc myocardial oxygen demand
Changes are referred to as
Hypertensive hypertrophic cardiomyopathy
Hypertrophic/hypertrophy
Increase in size of cells
As CO decreases
Renal perfusion is reduced
Results of renal perfusion
Further activation of RAAS pathway = continual increases in vasoconstriction and blood volume
Baroreceptors continue to detect
Decreased blood pressure which results in increased catecholamines release and inc vasoconstriction
Both activation of RAAS and Baroreceptors result in
Continued inc in both preload and afterload
Pharmacology
Inhibition of various aspects of RAAS and SNS
Left ventricular failure with preserved ejection factor
Defunded as pulmonary congestion despite normal stroke volume and cardiac output
Left ventricular failure with preserved ejection factor prevalence in population between
1-5%
Cause of Left ventricular failure with preserved ejection factor
Abnormal diastolic relaxation such that a normal left ventricle volume results in an inc left ventricle end diastolic pressure
Normal amount of blood returning to the heart results in
An increased ventricle pressure
This pressure is reflected back into pulmonary circulation and results in
Pulmonary edema and right ventricular hypertrophy
Diagnosis of Left ventricular failure with preserved ejection factor
-dyspnea on exertion
-fatigue
-evidence of pulmonary edema
Right ventricular failure
Inability of right ventricle to provide adequate blood flow into pulmonary circulation at a normal venous pressure
Cause of Right ventricular failure
Left ventricle failure = pressure reflected back into pulmonary system = pressure further reflected back into right ventricle
Right ventricle is poorly prepared for inc afterload and will
Dilate and fail
Result of Right ventricular failure
Systemic hypertension = peripheral edema
Right ventricular failure is referred to as
Cor pulmonale
Vide on slide 35