Heart Flashcards
Parts of an EKG (electrocardiogram)
-P-Wave : atrial excitation “hill like”
-QRS Complex : ventricular depolarization “fired up peak”
-T-Wave : ventricular re polarization (recharged)
Factors Affecting Heart Rate
- ANS (Autonomic Nervous System)
-medulla oblongata : influenced by Limbic system (emotional brain) such as stress - Hormones
-Adrenaline (–>)
-Caffeine
-O2 + CO2 in blood
-Nicotine (–>) - Lower BP
- myocardial hypertrophy (cardiac tissue getting thicker/bigger) = decrease heart rate
Bradycardia :
Tachycardia :
-Resting H.R below (<–) 60 bpm
- Resting H.R above 100 bpm
Electrical Conduction System
(to cause the heart muscle to contract, and pump blood through the body’s circulatory system)
Begins in the medulla oblongata –> Vagus nerve –> SA Node (pacemaker) –> AV Node –> bundle fibers –> purkinje fibers –> Myocardium
Ventricular Fibrillation :
Irregular contractions of myocardium
ex: a decrease of cardiac output = death
CO = HR x SV (stroke volume)
(Cardiac Output)
Cardiac Output = 70 bpm x 70 m/s
= 4,900 mL / min
Cardiovascular System: consists of
- Function
-Heart, arteries, arterioles, capillaries, venules, veins
- Transports gas
Heart :
-chambers
-H.R
- 4 chambers (upper=Atria, lower=Ventricles)
- normal resting H.R 60-80 bpm
Coverings/Walls of Heart:
-Lies in …
-Lies in the pericardial sac
- Epicardium “visceral pericardium” : outermost layer
- Myocardium : cardiac muscle, dark red, very vascular (lots of blood flow), myocardial atrophy (weaker due to aging) + hypertrophy ^^
- Endocardium : inner lining (very smooth, where blood comes into contact)
Artery :
vessel which transport blood AWAY from heart (DEEP)
- majority are red = oxygenated
- high pressure
- NO valves
- muscular
-Tunica intima: simple squamous epi. (elastic CT exposed for plaque development)
-Atherosclerosis : fatty plaque on an artery wall
-Arteriosclerosis : Ca+2 embedded in plaque (hardened)
Veins :
vessel which transports blood TOWARD the heart (SUPERFICIAL)
- low pressure
- has valves
- less muscle
- some veins are blue = deoxygenated
Blood Flow through the Heart :
(BLUE)
SVC / IVC > R atrium > Tricuspid valve ( R av valve) > R ventricle > through pulmonary valve > pulmonary trunk > pulmo. arteries > capilaries lung > (RED) pulmo. veins > L atrium > Bicuspid valve (L av valve) > L ventricle > aorta valve > aorta > arteries > bodies
Risk Factors
+ prevention
- Diet high in saturated fats
- smoking
- obesity
- stress
-diet (cut back on SF + cholesterol)
-exercise
-maintain body weight
-maintain stress
-STOP smoking
Treatment for Atherosclerosis
- Bypass surgery (utilizing the great saphenous vein)
- Angioplasty + stent (catheter w/balloon)
- Heart transplant
Blood Drawn
-Artery
Mediun cubital vein
- BP from brachial artery or femoral artery
Pulse : radial artery and dorsal pedal artery
Blood Pressure (bpm)
#/#
^=?
120(systolic, L ventricular contraction) / 80(diastolic, recoil of arteries composed of elastic c.t + smooth muscle)
Hypertension: 140/90
Hypotension: 90/60
Hypertension: 140/90
-prevention
: unhealthy bc undue stress on heart overtime causes congestive heart failure (back flow of blood edema) DAMAGE to kidneys/arteries. can CAUSE an aneurysm
-exercise, excess of saturated fats, calories, sodium, take meds, decrease of stress
Where is the breakpoint between oxygenated and deoxygenated? (when does the blood turn colors)
After the Lungs
Which heart chamber does the most work?
Left ventricle (pumps blood from head <–> toes) = thicker myocardium
Coronary Circulation :
- what supplies your heart w/blood
: Blood flow to the myocardium and back to the R Atrium
- two primary arteries ( L & R coronary arteries)
branch down into capillaries > myocardium > veins > cardiac veins > R atrium
Coronary Artery Disease :
affecting the lining of the artery which narrows it, the build up of calcium & cholesterol (build up = atherosclerosis)
Heart Disease :
- causes what?
: gradual progressive disease, where theres a blockage of coronary circulation
-causes a MI (myocardial infarction [sudden death] = heart attack)
Heart Disease :
- risk factors
- genetics
- smoking
- sedentary
- fatty diets
- high cholesterol
- aging
- diabetic
- male
- stress
- clotting disorder
Heart Disease :
- prevention
- exercise (aerobic) 3-4 days a week
- increase intake of fruits/veggies
- decrease fat/cholesterol & calorie intake
- don’t smoke
- learn how to relax + handle stress
Heart Disease :
- treatment
- Bypass surgery
- Angioplasty + stent (catheter w/balloon)
- Heart transplant
Atherosclerosis :
fatty plaque in artery wall
Arteriosclerosis :
hardened plaque (embedded w/calcium)
Fibrillation :
:asynchronous beating of the heart
Aneurysm :
expanded weakened artery wall, which can rupture and cause internal bleeding = stroke > death
