Flashcards in Class #1 Deck (58):
What are the 3 properties specific to Heart cells that help them create action potentials?
1. Automaticity--they can spontaneously initiate an action potential
2. Excitability--they can respond to an impulse and then generate their own action potential
3. Conductivity--they can conduct impulses
What is sinus bradycardia? What may be some signs and symptoms?
When the heart beat slows to less than 60bpm. Your patient would exhibit S&S of generalized decreased blood perfusion
What is sinus tachycardia? How does it affect the heart?
When the heart beat increases to more than 100bmp. This is normal with exertion or if you have a fever, because it is your body's normal way to compensate.
This is dangerous because it increases myocardial workload and decreases coronary artery perfusion.
What is the difference between sinus arrest and sick sinus syndrome?
Sinus arrest indicates temporary failure of an otherwise healthy SA node, and is usually intermittent. Sick sinus syndrome occurs as a result of SA node injury or damage
What is occurring during Premature Atrial Complexes (PAC)
Early depolarization originating in the atria, NOT the SA node.
What is Paroxysmal supraventricular tachycardia (PSVT)? Why does it happen?
When the HR occasionally spikes to 140-240/min. This rhythm has a sudden onset and an equally sudden cessation. It occurs d/t ischemia or reentry.
ALSO CALLED WOLFF-PARKINSON-WHITE-SYNDROME
Define Atrial Flutter
ectopic atrial tachycardia-- 250-450bmp. This usually occurs as a result of re-entry or ischemia.
What is occurring in the heart when a patient has Atrial Fibrillation?
Chaotic depolarization with only occasional contraction. The atria actually "quiver" because of chaotic electrical conduction. This will cause poor emptying of the atria, d/t decreased time to fill, which will lead to poor filling of the ventricles, which will cause poor Cardiac Output.
How will my patient with A.Fib present to me? What do they call this heart rhythm?
-Pulse will vary in strength at different times/different locations
-Pulse will often be thready
-Low Blood Pressure
**ALL other body systems will exhibit S&S of decreased cardiac output/decreased perfusion
They call this rhythm "Irregularly irregular"
Explain the different degrees of AV Block
1st Degree- Long PR, followed by QRS, AV node just isn't 100%, and takes an extra second to conduct electricity
2nd Degree- Less AV conductivity, dropped QRS
3rd Degree- NO electrical communication between atria and ventricles. Someone with 3rd degree AV block would need a pacemaker.
What is a Premature Ventricular Complex (PVC)?
Basically when the heart skips a beat, and this can happen d/t ischemia or necrosis. If it happens once randomly, it is called Isolated Ectopic PVC. If it happens twice in a row, its called couplet PVC. If it happens on every second beat, it is called Bigeminy (Bi-gem-in-ee) PVC
What is ventricular Fibrillation?
When the ventricles are quivering, which means there is no time for them to be filled, or for them to effectively pump, which means there is NO CARDIAC OUTPUT
What is the difference between LDL and HDL? Which one is better?
LDL is the main carrier of cholesterol but leaves some behind for uptake in the arteriole wall
HDL removes cholesterol from tissues and take it to the liver for disposal.
HDL IS GOOD CHOLESTEROL
Which lipoprotein is the main carrier for triglycerides?
Which lipoprotein is the main carrier for cholesterol?
What causes hyperlipidemia?
-High calorie diet, which increases VLDL and its conversion to LDL
List the non-modifiable risks for acquiring atherosclerosis.
age, gender, family history, genetically determined alterations in lipoprotein and cholesterol metabolism
What are some modifiable risks for acquiring atherosclerosis?
Smoking, poor diet, lack of exercise, obesity, HTN, Diabetes
What are 3 tests you can have done to determine whether or not you are at risk for atherosclerosis?
1. C-reactive Protein--indicates generalized inflammation
3. Increased serum lipoprotein
How does tobacco use increase your risk for atherosclerosis and other cardiovascular problems?
1. Increases blood lipid levels
2. Damages endothelium
3. Enhances and speeds up thrombus formation
4. Increases Blood viscosity
5. Increases circulating catecholamines--wears your body out on a long term basis
What's the difference between arteriosclerosis, arteriolosclerosis, and atherosclerosis?
1. hardening of M to L arteries
2. Hardening of S arterioles
3. Hardening d/t buildup of plaque
What is Peripheral Artery Disease? Who is at risk for this particular disease?
Atherosclerosis DISTAL to the aortic arch
- >60 yrs old
How might my patient with Peripheral Artery Disease present to me?
-intermittent claudication (pain in leg when walking)
-Thin skin and subcutaneous tissue
-atropy of muscles
DECREASE BLOOD SUPPLY:
-weak/absent pulse, cool extremeties, brittle nails/hair loss, pallor
What is "dependent rubor"?
Damage to the arteries that prevents them from moving blood effectively. This causes blood to pool in the legs and feet.
What are 2 common complications of Peripheral Artery Disease?
If you suspected your patient may have Peripheral Artery Disease, what diagnostic tests might you ask for?
-Blood pressure changes in the legs
-MRI Arteriography/Spiral CT arteriography
After my patient is diagnosed with Peripheral Artery Disease, what types of treatment might I expect the Doctor to order?
- walk to the point of claudication, to increase blood flow to the area
-Avoid surface injury, as they will be slow to heal
-Antiplatelet therapy (ASA, clopidogrel)
-Femoralpopliteal bypass grafting
-percutaneous transluminal angioplasty and stenting
What is Raynaud's Phenomenon?
Intense episodic vasospastic disorder of arteries and arterioles that causes (usually the tips of fingers) to go white when exposed to intense cold temperatures or strong emotions.
Your fingers would feel tingling and numb, aching and throbbing, and they would go from pale to cyanotic over time.
How can you treat Raynaud's Phenomenon?
-Avoid obvious triggers
-Avoid vasoconstrictive medications, as they may exacerbate this condition
*warm up your entire body, not just your hands!
LOOK UP TYPES OF ANEURYSMS!
JUST DO IT RIGHT NOW, NOT LATER!
I may suspect my patient has an Abdominal Aortic Aneurysm when...
they have a pulsating mass (if > 4cm) in their abdomen
C/O mild to severe abdominal and back pain
If a patient is having an aortic aneurysm, how might I expect them to present?
C/O substernal, back and neck pain
If an aneurysm is putting pressure on the trachea, how would my patient present? Laryngeal nerve? Esophagus? Superior vena cava?
Trachea: stridor, cough, dyspnea
Esophagus: difficulty swallowing
SVC: Facial/neck edema
What complications can arise from an aneurysm?
True or False?
A Dissecting aortic aneurysm often occurs d/t atherosclerotic changes?
Dessecting AA often occur without any atherosclerotic changes.
Who are at risk for a dissecting aortic aneursym?
40-60 yr old men
Congenital defects of aortic valve
How might my patient with a dissecting AA present to me?
-Excrutiating pain to anterior chest and back
-Blood pressure that is initially high, and then later -unobtainable in one or both arms
-Lower extremity hemiplegia/paralysis
**Heart failure if aortic valve involvement
What is Mean Arterial Blood Pressure (MAP)?
Represents the amount of pressure supplied to your organs
How do you calculate Cardiac Output?
Heart rate (HR) x Stroke Volume (SV)
*SV represents the amount of blood ejected from the heart with each single heart beat
What does blood pressure represent?
Cardiac Output x Systemic Vascular Resistance
Explain the neural mechanisms for regulating blood pressure
1. Medulla and lower pons, as the cardiovascular center in the brain
2. Vagus Nerve, which sends parasympathetic impulses to slow the heart rate
3. Spinal Cord sends sympathetic impulses to heart and blood vessels to increase heart rate and cause vasoconstriction, which increases BP
Differentiate between intrinsic reflexes and extrinsic reflexes for regulating blood pressure
INTRINSIC: baroreceptors which sense pressure changes and chemoreceptors which sense chemical changes, and both try to regulate against these changes
EXTRINSIC: diffuse reactions d/t physical pain, cold via hypothalamus
Explain the humoral mechanisms used to regulate blood pressure
1. Renin-Angiotensin-Aldosterone system, which is released in response to decreased volumes
2. Vasopressin (ADH)
True or False?
Hypertension in the leading cause of CV disorders?
What is the difference between primary hypertension and secondary hypertension?
Primary is chronic, but without evidence of any other disease process, and is caused naturally i.e. family history, race, older age, lifestyle factors
Secondary is HTN that results from another disorder i.e. Kidney disease, Adrenal cortical disorders, phoechromocytoma, coarctation of the aorta, pharmaceuticals, obstructive sleep apnea
Define target organ damage
Damage seen as a result of prolonged hypertension
My patient is in a hypertensive crisis when....
Emergency: diastolic >120
they have elevated BP with impending target-organ damage
Define orthostatic hypotension
Sustained drop in BP d/t a change in body position (usually when a patient stands up)
How might I know my patient is experiencing orthostatic hypotension?
*Objective drop in systole of 20 mmHg AND diastolic of 10mmHg*
Who are at high risk for getting varicose veins?
-individuals who are obese
->50 yrs old
What is the difference between primary and secondary varicose veins?
Primary-- superficial, and they are caused by prolonged standing, pregnancy, abdominal pressure, prolonged heavy lifting
Secondary-- affect deeper veins,caused by other diseases, like arteriovenous fistulas, venous marlformations, tumors or pregnancy
What is chronic venous insufficiency?
chronic venous hypertension causes dilation and stretching of vessel walls over time. This causes impaired blood flow, resulting in edema, impaired tissue nutrition, ischemia/necrosis, brown pigmentation, stasis dermatitis, venous ulcers.
Explain Virchow's Triad
3 factors associated with risk of thrombosis
1. Stasis (bed rest, SC injury, venous obstruction)
2. Vessel wall injury (venous catheters, surgery, #hip)
3. Hypercoaguability (genetics, stress/trauma, pregnancy, oral contraceptives, dehydration, cancer
What are some signs of systems of a DVT?
*can be asymptomatic if the vein is not completely occluded*
-deep muscle tenderness
-signs of inflammation
If not treated appropriately, what is a complication that may arise from a DVT?
How can I treat a patient with a DVT?
-proactive prevention (SCD)
-Elevate the limb
-Gradual ambulation with elastic support
In atherosclerosis, What's the difference between "stable plaques" and "Unstable Plaques"?
Stable: thick fibrous caps, only partially block vessels, and don't tend to cause clots/emboli
Unstable: have thin fibrous caps, which make them susceptible to rupture, causing clot formation, which may break free and cause damage. These unstable plaques may completely block the artery