Pulmonary circuit
Pumps deoxygenated blood towards lungs for oxygenation and back to the heart
Systemic circuit
Delivers oxygenated blood through body and back to the heart
Atria
2 superior chambers of heart; receive blood from pulmonary and systemic circuit
Ventricles
2 inferior chamber of heart; larger and have more musculature because they pump blood through pulmonary and systemic circuits
Apex
Point of heart; lies left of midline
Base
Superior portion of heart
Mediasternum
Heart is located in (central thoracic area between lungs)
Pericardium
Covering of the heart that consists of two layers
Fibrous pericardium
Strong layer of dense connective tissue; most superficial layer
Serous pericardium
Deeper layer of the pericardium which surrounds the heart; consists of two layers (parietal and visceral) separated by a cavity
Epicardium
Another name for the visceral serous pericardium that surrounds the heart
Myocardium
Cardiac muscle that makes up muscular wall of heart; located between epicardium and endocardium; have circular/spiral arrangement in the heart
Endocardium
Thin layer of connective tissue that lines the heart wall (muscle) and forms the inner lining
Pericardial cavity
Space between parietal serous pericardium and visceral serous pericardium; filled with fluid which lubricates membranes and allows heart to slide across them
Interventricular septa
Separates left and right ventricles
Interatrial septa
Separates left and right atrium
Superior and inferior vena cava, right atrium, tricuspid valve, right ventricle, pulmonary semilunar valve, pulmonary trunk, lung capillaries, pulmonary veins, left atrium, bicuspid valve, left ventricle, aortic semilunar valve, aorta
Order of blood flow through the heart starting from vena cava and including valves
Coronary arteries
Blood vessels that supply the heart with oxygenated blood; located on external heart
Coronary sulcus
Groove where coronary arteries run through located between atrium and ventricles on external surface
Superior vena cava
Deoxygenated blood from systemic circuit above the level of the heart drains into...
Right atrium
Heart chamber that makes up right border of the heart; receives blood from superior and inferior vena cava and coronary veins; contains sinoatrial node and fossa ovalis
Inferior vena cava
Venous blood from below the level of the heart drains into ...
Sinoatrial node
Pacemaker of the heart located in the wall of the right atrium and control rhythm of heart beat; creates a signal that travels to both atria and signals all muscle cells to contract together
Fossa ovalis
Remnant of a hole from embryonic heart that connects left and right atrium to bypass pulmonary circuit; closes with change in pressure at birth to form ...
Foramen ovale
Hole in embryonic heart that connects right and left atrium to bypass pulmonary circuit
Tricuspid valve
Connects right atrium and right ventricle and prevents blood from regurgitating back into right atrium
Chordae tendinae
Fibers that anchor atrioventricular valves (tricuspid and bicuspid)
Papillary muscles
Structures that control chordae tendinae to open atrioventricular valves through their contraction
Right ventricle
Oxygen is still deoxygenated when pumped from right atrium into this chamber of the heart; it needs to be pumped into pulmonary circuit
Pulmonary valve
Structure found in pulmonary trunk that keeps blood from regurgitating back into right ventricle and reversing blood flow
Pulmonary trunk
This structure of the heart bifurcates into left and right pulmonary arteries and contains pulmonary valve
Pulmonary veins
Blood is oxygenated in the lungs and returns to heart via these structures (vessels)
Left atrium
Pulmonary veins drain oxygenated blood into this chamber of the heart
Bicuspid valve
Also called mitral valve or left atrioventricular valve; oxygen rich blood crosses this structure from left atrium into left ventricle; it prevents blood from regurgitating back into left atrium; contains chordae tendinae and papillary muscles
Left ventricle
Oxygen rich blood is pumped into aorta from this heart chamber
Aortic valve
Semilunar valve that prevents blood from regurgitating from atrium back into left ventricle
Aorta
First large artery of systemic circuit; contains semilunar valve; branches into smaller arteries to supply oxygen rich blood to body
Endocardium
Each valve is composed of ... with a connective tissue core
Semilunar valves
Valves that are located at the junction of ventricles and great arteries of pulmonary/systemic circuit
Cardiac skeleton
Dense connective tissue structure that surrounds all valves that functions to anchor valve cusps, prevent overdilation, blocks direct spread of impulses, and is the main point of insertion for cardiac muscle
Open
Blood filling the atria and pressing against AV valves causes increased pressure causes AV valve to ... then atrium contracts and pushes rest of blood through
Close
Ventricles contracting causes blood to push against valves and ... them; papillary muscles and chordae tendinae prevent flaps from going into atria
Open
When ventricles contract and pressure rises blood is pushed against semilunar valves causing them to ...
Closed
When ventricles relax pressure falls and blood flows back from arteries filling cusps of semilunar valves and forcing them ...
Atrioventricular
The first lub sound of a heart beat is characteristic of these valves closing
Semilunar
Second dub sound of heart beat is characteristic of these valves closing
2nd right parasternal space
Aortic valve is best heard at
2nd left parasternal intercostal space
Pulmonary valve is best heard at
5th left parasternal intercostal space
Tricuspid valve is best heard at apex of heart located at
5th left intercostal space at midclavicular line
Mitral valve is best heard at
Systole
Contraction of heart chamber (atrium or ventricles)
Diastole
Expansion of heart chamber (atrium or ventricle) after contraction when it refills with blood
Tachycardia
Elevated heart rate 100 bpm+
Bradycardia
Depressed heart rate <60 bpm
Left ventricle
This ventricle has thicker myocardium because it pumps blood to systemic circuit
HOCM
Congenital disorder of the heart wall with enlarge interventricular septum; decreases blood flow of left ventricle and systemic circuit; dangerous during exercise when blood flow to brain or vital organs can be blocked; distinct heart murmur; pre-screening is important for athletes
Myocardium
Name for cardiac muscle; is striated like skeletal muscle and contracts via sliding filament mechanism; contraction pumps blood from heart and vessels
Desmosomes, fasciae adherens, gap junctions
Cell junctions that hold cardiac muscle together
Fasciae adherens
Long desmosome-like junctions
Gap junctions
Hollow channels that allow cardiac muscle cells to communicate quickly and contract together (neurotransmitters are inefficient)
Calcium
Cardiac muscle is stimulated to contract by ... entering sarcoplasm which signals release of more ... by sarcoplasmic reticulum to trigger sliding filament mechanism
Conducting system
System of cardiac muscle that generates and conducts impulses and signals cells to contract rhythmically; includes specialized muscle cells like sinoatrial node
Sinoatrial node, atrioventricular node, atrioventricular bundle, bundle branches, purkinje fibers
List the pathway of the conducting system
Sinoatrial node
First part of conducting system that creates signal that travels to both atria and stimulates muscle cells to contract together
Atrioventricular node
Conduction from sinoatrial node comes back into the right atrium at the top of atrioventricular septum to this structure
Atrioventricular bundle
Signal of conducting system goes down atrioventricular node to this structure located in interventricular septa
Bundle branches
Structures of conducting system that descend down interventricular septa to apex of heart
Purkinje fibers
Distal bundle branches that stimulates contraction of both ventricles
Depolarization
Cardiac muscle cell is more positively charged
Repolarization
Cardiac muscle returns to normal
QRS
This portion of an ECG graph represents the biggest electrical activity caused by the bundle branches of the conducting system and signals ventricles to contract
P wave
Part of ECG that represents atrial contraction or systole
T wave
Part of ECG that represents repolarization/relaxation/diastole to normal shape
Sinus
How often heart is beating; part of ECG usually 60-100 bpm
Atrial fibrilation
This condition is characteristic of no defined P wave in ECG, atria is not contracting well
Heart block
Results due to slow communication between atria and ventricles
Third degree heart block
Results in no communication between atria and ventricles; contraction occurs randomly and independently
Parsympathetic
Innervation of this division of the ANS decreases hear rate through parasympathetic fibers that run in vagus nerve; cardiac center located in medulla
Sympathetic
Innervation of heart from this division of the ANS increases heart rate and contractile force to pump more blood through systemic circuit
Coronary arteries
Blood supply to muscular walls and tissues of hear arises from base of aorta and runs through coronary sulcus; left and right
Right coronary artery
Blood vessel originates from aorta and travels between right atrium and right ventricle on surface of the heart then travels posteriorly
Left coronary artery
Blood vessel originates from aorta and passes behind pulmonary trunk toward left margin of the hear below the left atrium and bifurcates into anterior interventricular artery and circumflex arteryA
Anterior interventricular artery
Branch of left coronary artery that supplies most of left ventricle; called widow's maker because most common artery to be blocked
Circumflex artery
Branch of left coronary artery that goes toward the back of the heart and supplies lateral wall and posterior left ventricle
Cardiac veins
These blood vessels carry deoxygenated blood from heart to right atrium; they occupy sulci on heart surface; example includes coronary sinus
Coronary sinus
Blood vessel of heart that runs in posterior part of coronary sulcus; returns majority of venous blood from heart to right atrium; cardiac veins drain into this structure on posterior heart
Great cardiac vein, middle cardiac vein, small cardiac vein
Name the major veins of the heart that drain into coronary sinus and into right atrium (3 of them)
Atherosclerosis
Fatty deposits in lumen (hollow opening of blood vessels) of coronary arteries
Angina
Chest pain associated with partial or full blockage of coronary artery
Myocardial infarction
Complete blockage of coronary artery due to severe atherosclerosis; causes cardiac muscle tissue to die; also called heart attack
Heart failure
Progressive weakening of the heart where it cannot meet body's demands for oxygenated bloodCon
Congestive heart failure
Heart overcompensates for weakness due to heart failure and becomes enlarged; reduces pumping efficiency
Angioplasty
Treatment for myocardial infarction where catheter is threaded into blocked coronary artery and balloon is inflated to open blood vessel and restore blood flow
Coronary bypass
Treatment of myocardial infarction; blood vessel is collected from other part of body and sutured to exposed coronary artery to create bypass for blockage
Partial bypass
Treatment for myocardial infarction where diagnosis of atherosclerosis results in prescription of blood thinning medication to prevent blockage
Arrythmias
Variation of normal heart rhythmVe
Ventricular fibrillation
Type of arrhythmia that results in rapid and random firing of electrical impulses in ventricles; crippled conducting system; common cause of cardiac arrest; fluttering instead of complete contraction/relaxation; insufficient blood pumping to systemic circuit; leads to fainting or collapse
Atrial fibrillation
Type of arrhythmia where impulses circle within atrial myocardium stimulating AV node; promotes clot formation and leads to stroke or pulmonary embolus when clot gets stuck in smaller capillaries; episodes of anxiety, fatigue, shortness of breath and palpitations; fibrillation requires correction
Ventricular septal defect
Most common congenital heart defect; consists of a hole in septa that causes oxygen rich and oxygen poor blood to mix into systemic circuit; inadequately oxygenated blood is pumped to tissues and ventricles work harder to increase blood flow; results in fatigue/fainting
Transposition of great vessels
Congenital heart defect where aorta is connected to right ventricle and pulmonary trunk is connected to left ventricle; requires surgical correction; deoxygenated blood passes to systemic circuit and oxygenated blood gets recycled in pulmonary circuit; great vessels are in the wrong place (reflected)