-
Tunica media
smooth muscle layer that plays the biggest role in blood pressure regulation
-
Tunica externa
composed of collagen
-
BP =
CO X Peripheral Vascular Resistance
-
CO =
stroke volume x heart rate
-
Amount the left ventricle pumps out over one minute
cardiac output
-
Short term regulation of blood pressure
- minutes to hours
- autonomic nervous system
- humoral mechanisms
-
Long term regulation of blood pressure
- daily, weekly, monthly
- kidney role in regulating fluid
-
acts on aldosterone (sodium/water retention) which increases CO
aldosterone antagonists
-
acts on kidney/intestin reabsorption of sodium and water which increases CO
diuretics
-
Vasopressin
- increases CO
- increases PVR
-
acts to counteract Sympathetic discharge which causes increased CO
central alpha 2 agonists
-
Actos on vascular smooth muscle vasoconstriction
- calcium channel blockers
- vasodilators
-
Acts on heart contractility
- beta adrenergic blockers
- non-DHP CCBs
-
How does lisinopril lower BP?
decreases PVR
-
Autonomic Nervous system regulation of BP mechanisms
- baroreceptors
- chemoreceptors
- external stimuli
-
Humoral mechanisms for regulating BP
- vasopressin (ADH)
- Renin-angiotensin-aldosterone system
-
Risky amount of salt for developing HTN
2.4 g/day or 6 g/day NaCL
-
Causes of secondary HTN
- sleep apnea
- aldosteronism
- chronic kidney disease
- renal artery stenosis/aortic stenosis
- pheochromocytoma/intracranial tumor
- cushing's syndrome/thyroid/parathyroid
-
Drugs that can induce HTN
- NSAIDS
- Cocaine
- Amphetamine
- Oral contraceptives
- Glucocorticoids/cyclosporin/tacrolimus
- EPO
-
Pseudoresistance
blood pressure elevated secondary to medication or white coat syndrome
-
Top concerns with HTN
- target organ damage
- mainly CV, stroke and kidney failure
-
Orthostatic hypotension
- baroreceptor response isn't working properly
- decrease in bp when switching to upright position
-
Diagnosis of orthostatic hypotn
- systolic drop >20mmHG within 3 min of standing
- diastolic drop >10mmHg within 3 min of standing
-
Symptoms of orthostatic hypotension
- dizziness
- blurred vision
- palpitations presyncope
-
most common risk factor for orthostatic hypotension
age
-
Arterial disorder
- decreased blood flow to tissues
- impared oxygen and nutrient delivery
-
Venous disorder
- interference with outflow of blood
- interference with removal of waste
-
Adverse events upon endothelial damage to arteries
- plasma and wbc are drawn to the area
- they uptake cholesterol and transition to foam cells
- fibrous cap forms
- necrotic core forms
- leads to vessel occlusion
-
Atherosclerosis of primary arteries
hardening of the arteries
-
Thrombosis leads to
- (plaque formed in arteries)
- Coronary Heart disease
- ischemic heart disease
- stroke
- peripheral artery disease
- aneurysms
-
Risk factors for thrombosis
- Hyperlipidemia
- age/family history
- male
- cigarettes
- HTN, DM
- elevated inflamatory markers (c-reactive protein)
-
Lipoproteins
- carry cholesterol
- carry triglycerides
-
Chylomycrons
- 80-90% triglycerides
- cary triglycerides in the blood
-
VLDL
- 55-65% triglycerides
- released from liver
-
-
-
Primary Hyperlipidemia
- increased sensitivity to dietary cholesterol
- lack of or defective LDL receptors
- Cellular defects in use of cholesterol
- altered synthesis of apoproteins
-
Secondary hyperlipidemia
- due to lifestyle
- obesity
- high calorie diet
- DM
-
Clinical presentation of primary HLD
- Familial: LDL 250-1000 mg/dl
- MI very early in life
-
Clinical presentation of secondary HLD
coronary artery disease
-
optimal LDL levels
<100 mg/dl
-
optimal total cholesterol
<200 mg/dl
-
optimal HDL cholesterol
between 40 and 60 mg/dl
-
Ischemia
reductino in arterial flow resulting in insufficient oxygenation to meet needs
-
Infarction
are of ischemic necrosis resulting from occlusion of arterial supply or venous drainage
-
Management of HLD
- increase physical activity
- smoking cessation
- diet modification/weight loss
- medication
- increase HDL
-
Peripheral artery disease
- usually in lower extremities
- gradula vessel occlusion
- impairs circulation
-
Risk factors for peripheral artery disease
- male
- increasing age
- atherosclerosis
- cigarettes
- DM
-
Clinical presentations of PAD
- painful walking (claudication)
- aches, numbness
- muscular atrophy
- weak pulse, cool temp, blanching when leg raised
- deep red color when leg lowered
-
Visual Diagnosis of PAD
- brittle toenails
- Hairloss
- pallor
- coolness
- atrophy
-
Palpable diagnosis of PAD
pedal pulses
-
Other exams to test for PAD
- ankle-brachial index
- ultrasound
- MRI, CT
-
Management of PAD
- adjust risk factors
- medications
- surgery
-
Aneurysm
- localized dilation of blood vessel
- occurs in arteries and veins
- most common in aorta
-
Risk factors for aneurysm
- atherosclerosis
- HTN
- congenital defects
- trauma/surgery
- infection
- pregnancy
-
Clinical presentation of aneurysm
- asymptomatic
- substernal, back or neck pain
- dyspnea, stridor, cough
- hoarsness
- edema
- pulsating mass
-
Risk factors for varicose veins
- standing
- blockage of veins
- pregnancy
-
3 components of pathophysiology of a thrombosis
- endothelial injury
- hypercoaguable state
- circulatory stasis
-
when a thrombus breaks off and moves it is called an
embolus
-
Clinical presentation of DVT
- deep leg pain
- calf tenderness
- erythema (red and warm)
- edema
- homans' sign
-
assesment for a DVT
- venous duplex (look at blood flow)
- d-dimer (test for remnants of clots in blood)
-
Pulmonary embolism
blood borne substance lodged in the pulmonary artery
-
PE can cause
- obstruction of pulmonary circulation
- reflex bronchoconstriction
- infarction is uncommon (ischemia)
-
Major problem with PE
lack of gas exchange
-
Assesment for pulmonary embolism
- d-dimer
- CT scan of lungs
- Lung scan
-
Complications of PE
- pulmonary hypertension
- right heart failure
- extension of clot
- mortality rate >30%
-
Cardiac conduction system
- sinoatrial node
- atrioventricular node
- bundle of his
- purkinje fibers
-
SA node
- pacemaker of heart
- 60-100 bpm
-
AV node
- only connection between atria and ventricle
- 40-60 bpm
-
Bundle of His
- predisposed to dmg due to calcification or infection
- blood supply is from main coronary arteries
-
Purkinje fibers
15-40 bpm rate of firing
-
Resting phase
selectivley permeable to K+
-
Repolarization
pumps Na+ out using ATPase (digoxin action)
-
5 phases of cardiac AP
- depolarization
- repolarization
- plateu
- rapid repolarization
- resting
-
Plateu phase of cardiac AP
- only in cardiac cells
- allows for 3-15x longer contraction
-
Fast response APs in the heart
-
-
absolute refractory period
cannot be stimulated
-
relative refractory period
- below threshold
- respond to greater than normal stimulus
-
P wave
depolarization of atria
-
QRS complex
ventricular depolarization
-
T wave
ventricular repolarization
-
Causes of cardiac arrhythmias
- myocardial injury
- congenetal defects
- fluid or e- imbalance
- medications
-
for mechanisms contributing to arrhythmias
- automaticity
- excitability
- conductivity
- refractoriness
-
Tachyarrhythmia
- result of reentry
- electric current feeds back and initiates a new current
-
Sinus bradycardia
- slow heartrate <60 bpm
- vagal stimulation (coughing or bearing down)
- may pass out
-
Sinus tachycardia
HR >100 bpm
-
Sinus arrest
- SA node fails
- AV node has to take over but is slower
-
supraventricular arrhythmia
- premature atrial contraction
- causes a pause in the SA node
-
Paroxysmal supraventricular tachycardia
- Rapid HR
- caused by abnormal reentry
-
Atrial flutter
- supraventricular arrhythmia
- extopic tachycardia (reentry loop)
- saw tooth ECG
-
Atypical flutter
reentry because of L atria
-
typical flutter
caused by dmg to R atria
-
Atrial fibrillation
- most common chronic arrhythmia
- reentry circuits constatly arrising in the atria
- 400-600 atrial beats
- 80-180 ventricle beats
-
Paroxysmal A fib
- recurrent episodes that self terminate
- lasts less than a 24hrs - 1 week
-
Persistent A fib
- reccurrent episodes that last for more than 1 week
- stop only with treatment
-
permanent A fib
ongoing long-term episode
-
Atrial fibrillation assesment
- No identifiable P wave
- loss of atrial kick causes ventricles to depolarize irregular too
-
A. Fib lowers CO by
10-20%
-
Complications of A. Fib.
- Hypotension
- loss of CO
- fatigue
- syncope
- thrombus/risk of stroke
-
Treatments for A. FIb
- anticoagulation
- shock therapy (after anti coag unless onset is known to be current)
-
Rate control
decrease heart rate to 60-100 bpm
-
Rhythm control
convert to normal sinus rhythm with medication
-
Ventricle arrhythmias
- premature ventricular contractions
- ventricular tachycardia
- torsades de pointes
- ventricular flutter/fibrillation
- more serius than atrial
-
Premature ventricular contractions
- "skipped beat"
- may lead to v fib
- no real P wave
-
causes of premature ventricular contractions
- e- imbalance
- infection
- premature ventricular contraction
-
Ventricular tachycardia
- life threatening
- 70-250 bpm
- increased automaticity in the ventricles
- CO is non existant
- more than 30 sec needs intervention
-
Torsades de Pointes
- prolonged QT interval
- unstable
- usually caused by medications
-
Ventricular flutter/fibrillation
- fatal rhythm
- no cardiac output
- no identifiable waves
-
complications of ventricular arrhythmias
- rapid heart beat
- dizziness
- Sob
- loss of pusle
- death
-
Atrioventricular conduction disorders
- first, second and thrid degree blocks
- secong degree has 2 types
-
First degree AV block
- prolonged PR interval
- delay in SA and or AV node
-
Second degree AV block type I
- wenkelback or mobitz
- progessive lengthening of PR interval until a beat is skipped
- usually occurs with right side MI
-
Type 2 second degree AV block
- Mobitz II
- dropped ventricular contraction
- PR with no QRS when there should be
- inferior wall MI ischemia
- can quickly lead to third degree
-
Third degree AV block
- complete heart block
- independent atrial and ventrical rates
- fainting spells
- usually caused by MI or ischemia
- decreased CO
-
Pharmacologic treatments for arrhythmias
- sodium channel blockers
- beta blockers
- potassium channel blockers
- calcium channel blockers
-
Pacemaker used for
- sinus bradycardia
- pace atria, ventricle or both
-
cardioversion
- direct current
- syncronized during refractory period
- planned procedure
-
defibrillation
- no synchronizing
- goal is to stop miss firing
-
alblation
- go through vein and use radio frequency to detect beat and counteract it
- cardiac cath lab procedure
-
surgery
coronary artery bypass
-
Pericarditis
- inflammation of the pericardium
- acute < 2 weeks
-
causes of pericarditis
- infections
- ischemia
- physical damage
-
signs and symptoms of pericarditis
- chest pain
- pericardial friction rub
- ECG changes
-
Treatment of pericarditis
-
Pericardial Effusion
- caused by pericarditis
- accumulation of fluid in the pericardial cavity
-
causes of pericardial effusion
- neoplasms
- surgery/trauma
- MI
-
signs and symptoms
- small = none
- large = heart failure symptoms
- shortness of breath
- edema
-
Diagnosis of pericardial effusion
echocardiogram
-
Echocardiogram examins
- ejection fraction
- pericardial disease
- valvular dysfunction
-
TTE echo
- probe is external
- 1st line choice
-
TEE echo
- invasive procedure
- tube sent through esophagus
- closer to the heart
- used if TTE is negative
-
Cardiac Tamponade
- life threatening form of pericardial effusion
- compression of heart chambers
-
signs and symptoms of cardiac tamponade
- pulsus paradoxus
- tachycardia
- distant heart sounds
-
treatment of cardiac tamponade
- pericardiocentesis
- pericardial window
-
Infective endocarditis
- infection on the inner serface of the heart
- colonization of heart valves leading to destruction
-
Signs and symptoms of infective endocarditis
- fever, high wbc, + blood culture
- new or changed heart murmur
- evidence of embolic complication
-
Osler nodes
- painful and raised
- sign of infective endocarditis
-
Janeway lesions
- thrombolic
- not raised or painful
- sign of infective endocarditis
-
Major risk factors for infective endocarditis
- mitral valve prolapse
- prosthetic heart valves
- IVDU
-
valve patients have this bacteria
staph epi
-
IVDU have this bacteria
staph aureus
-
other bacteria that can cause endocarditis
streptococci and enterococci
-
Diagnosis of infective endocarditis
- echocardiogram (TTE then TEE)
- Blood culture
- modified duke criteria
-
Treatment of infective endocarditis
- long term antibiotics
- surgery
-
Major signs of infective endocarditis
- + blood culture
- positive TTE or TEE
-
Minor criteria for infective endocarditis
- high risk patient
- + blood culture
- fever
- vascular phenom (stroke, janeway...)
- immunologic phenom
-
Definite diagnosis via modified duke criteria
- 2 major
- 1 major + 2 minor
- 5 minor
-
Possible diagnosis of infective endocarditis
- 1 major and 1 minor
- 3 minor
-
Pulmonary valvle
right ventricle to pulmonary artery
-
Tricuspid valve
right atrium to right ventricle
-
mitral valvle
left atrium to left ventricle (oxy)
-
aortic valve
left ventricle to aorta (oxy)
-
most commonly effected with valvular heart disease
- left heart
- higher pressure
-
Stenosis
- opening problem
- narrowing of valve
- sx with exercise
-
Refurgitant valvular heart disease
- closing problem
- valve permits backflow
-
signs and symptoms of mitral valve stenosis
- pulmonary congestion
- left atria enlargement (may cause Afib)
- decreased cardiac output
- paroxismal nocturnal dyspnia
- palpitations
- chestpain
- diastolic murmur
-
Mitral valve regurgitation
- pulmonary congestion
- left atria and ventricle enlargement (may start afib)
- decreased CO
- mild case no symptoms, major case = shock
- holosystolic murmur (high pitch)
-
Mitral valve prolapse
- risk for endocarditis
- more common in women
- mid systolic clicks
-
aortic valve stenosis
- LV enlargement of muslce
- decreased CO
- angina, syncope, HF
- loud systolic ejection murmur or split S2
- no medical therapy
-
Aortic valve regurgitation
- LV enlargement
- increase CO at first but then falls (frank starling)
- sever cases = HF, PND, orthopnea
- water hammer pulse
- high pitched diastolic blowing murmur
-
Treatment for valvular heart diseases
- routine checks
- surgery
- medications
- repair or replace valve
- long term anticoag
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