Circulation + Perfusion chp 38 Physical Assessment Flashcards
Circulation
flow of blood throughout the heart and blood vessels
Perfusion
describes blood flow to a capillary bed to provide nutrients and oxygen to tissues and organs
Cardiac Cycle
simultaneous contraction of the two atria, followed by a fraction of a second later the simultaneous contraction of the ventricles
Electrical Conduction
electrical activity that initiates contraction of the myocardium
Sinoatrial (SA) Node
pacemaker of the heart
Atrioventricular (AV) Node
electrical activity passes through the AV node into the left and right bundles of HIS and into Purkinje Fibers to the ventricles
Arteries
oxygenated blood to tissues
Veins + Venules
deoxygenated blood back to heart/ lungs
Hemoglobin
carries oxygen
4 Chambers of the Heart
Two Atria: act as reservoir, receives blood returning via veins from body + lungs
Two Ventricles: larger, thicker
-pumps blood to lungs + body
4 Valves of the Heart
Two Atrioventricular Valves:
1. Tricuspid
2. Mitral
Two Semilunar Valves:
1. Pulmonic (separates right ventricle from pulmonary artery)
2. Aortic (separates left ventricle from aortic artery)
Apical Pulse
PMI
- apex of the heart
- at the bottom of heart
- where left ventricle almost touches chest
- left ventricle contracts and forms apical pulse
- PMI (point of maximal impulse)
- PMI located at 5th ICS left midclavicular line
Characteristics of Normal Heart Sounds
>Lub -first heart sound -S1 -Mitral + Tricuspid Valves >Dub -2nd heart sound -S2 -Aortic + Pulmonic Valves
Correct Order of Auscultation
All Physicians Take Money
A= Aortic Valve
P= Pulmonic Valve
(S2 DUB)
T= Tricuspid Valve
M= Mitral Valve
(S1 LUB)
Coronary Arteries
- heart has its own blood supply to the heart
- fill during diastole
- from the coronary sinus, blood flows into the two main coronary arteries, which branch into several sections to supply the heart muscle with blood
- the coronary arteries are the only arteries in the body that fill during diastole
Autonomic Nervous System
- sympathetic fibers
- parasympathetic fibers
> heart: regulate heart rate + contractility
Vascular system: maintain vascular tone
Factors that Influence Cardiac function
- developmental stage
- environment
- stress
- allergic reactions + air quality
- heat + cold
- medications
- lifestyle
- nutrition
- exercise
- obesity
- heredity
- tobacco use
- substance abuse
- pregnancy
- pathophysiological conditions
Factors that Influence Cardiac Function in Older Adults
- thicker, more rigid valves
- decreased myocardial strength
- lower exercise tolerance
- health problems
Heart Failure
Pathophysiological condition
- occurs when the heart becomes an inefficient pump and is unable to meet the body’s demands
- blood is oxygenated when it passes through the lungs, but is not well circulated to the organs + tissues
Cardiomyopathy
Pathophysiological condition
-heart muscle disorder that results in heart enlargement and impaired cardiac contractility
Cardiac Ischemia
Pathophysiological Condition
-occurs when oxygen requirements of the heart are unmet
-prolonged ischemia leads to myocardial infarction (MI) as parts of the heart necroses (die) from inadequate oxygen
-angina pectoris is transient pain in chest due to MI
(tissue becomes injured but does not necrose)
Coronary Artery Disease
leading cause of cardiac ischemia
-condition in which plague builds up inside the coronary arteries
-plague narrows the arteries reducing blood flow to the heart muscle
(more likely clots will form and block the arteries)