The Cardiovascular System Flashcards
The cardiovascular system is what type of system?
Closed
blood vessels that carry blood away from the heart
Arteries
blood vessels that carry blood to the heart
Veins
tiny blood vessels that form the transition between arteries and veins
Capillaries
List the 2 types of circulation in the cardiovascular system
- Pulmonary Circulation
- Systemic Circulation
Which side of the heart controls pulmonary circulation vs systemic circulation?
Pulmonary Circulation - right side
Systemic Circulation - left side
the space in the thoracic cavity between the lungs
Mediastinum
List the 7 structures contained in the mediastinum
- Heart
- Blood vessels
- Trachea (thoracic portion)
- Esophagus
- Thymus (young animals)
- Lymph nodes
- Nerves
the rounded, cranial end of the heart
Base
the more pointed, caudal end of the heart
Apex
the line drawn from the apex to the base of the heart
Long Axis
the fibrous membrane that surrounds the heart and is divided into two layers
Pericardium
the portion of the pericardium that is loose enough for the heart to comfortably beat inside of it but is not elastic and cannot stretch if the heart becomes enlarged
Pericardial Sac
the portion of the pericardium that produces the pericardial fluid that lubricates the heart as it beats
Serous Pericardium
Give the 2 divisions of the pericardium
- Pericardial Sac
- Serous Pericardium
What are the 2 layers of the serous pericardium?
- Parietal Layer
- Visceral Layer (Epicardium)
a smooth, moist serous membrane that lines the pericardial sac
Parietal Layer
a smooth, moist serous membrane that lies directly on the surface of the heart
Visceral Layer (Epicardium)
the region between the parietal layer and visceral layer of the pericardium that is filled with a lubricating fluid
Pericardial Space
the lubricant between the parietal layer and visceral layer of the pericardium that prevents friction as they rub together during contractions and relaxations of the heart muscle
Pericardial Fluid
Give the 3 layers of the heart wall
- Epicardium
- Myocardium
- Endocardium
the outermost layer of the heart wall
Epicardium (Visceral Layer of the Serous Pericardium)
the thickest layer of the heart
Myocardium
the layer of the heart wall that forms the lining of the heart chambers and covers the heart valves
Endocardium
What are the 2 types of chambers in the heart
- Atria
- Ventricles
the chambers that receive blood into the heart and whose walls form the base of the heart
Atria
the continuation of the myocardium that separates the left and right atria
Interatrial Septum
pouches on the anterior surface of each atria that increase the capacity of each atrium and help pump blood within the heart
Auricles
the chambers that pump blood out of the heart and whose walls form the apex of the heart
Ventricles
the chamber of the heart that pumps blood into the systemic circulation through the aorta
Left Ventricle
the chamber of the heart that pumps blood to the pulmonary circulation through the pulmonary artery
Right Ventricle
the continuation of the myocardium that separates the left and right ventricles
Interventricular Septum
the area of the interventricular septum that is visible on the outside of the heart, contains coronary blood vessels, and is often filled with fat
Interventricular Groove
related to the heart
Coronary
Which ventricular myocardium is thicker? Why?
Left because it needs to pump blood to the rest of the body
formed from the interventricular septum and the interatrial septum
Atrioventricular Septum
flaps of endothelium that open when the pressure from the amount of blood in the atrium forces it open and allows blood to flow into the ventricle, as well as snaps shut when pressure from the blood in the ventricle exceeds that of the atrium
Cusps
collagen fiber cords attached to the edge of each atrioventricular cusp and the papillary muscles
Chordae tendonae
What are the 2 types of valves in the heart?
- Atrioventricular Valves
- Semilunar Valves
the heart valves that control blood flow between the atria and ventricles
Atrioventricular Valves
List the 2 atrioventricular valves
- Bicuspid / Mitral Valve (Left AV)
- Tricuspid Valve (Right AV)
the atrioventricular valve located between the left atrium and the left ventricle
Bicuspid / Mitral Valve
How many cusps does the mitral valve have?
2
the atrioventricular valve located between the right atrium and the right ventricle
Tricuspid Valve
the heart valves that control blood flow out of the ventricles and into arteries
Semilunar Valves
List the 2 semilunar valves in the heart
- Aortic Valve
- Pulmonary Valve
the heart valve that controls blood flow from the left ventricle into systemic circulation
Aortic Valve
the heart valve that controls blood flow from the right ventricle into the lungs
Pulmonary Valve
How many cusps does the aortic valve have?
3
How many cusps does the pulmonary valve have?
3
Where is the skeleton of the heart located?
Between the atria + ventricles
1. Root of pulmonary trunk
2. Root of aorta
3. Ring for right AV
4. Ring for left AV
What is the skeleton of the heart made of?
4 dense fibrous connective tissue rings
Give the 4 functions of the skeleton of the heart
- Separates atria + ventricles
- Anchors the heart valves
- Point of attachment for myocardium
- Some electrical insulation between atria + ventricles
branch off the aorta just past the aortic valve and supply oxygenated blood to the heart muscle
Coronary Arteries
Which chamber in the heart gets the largest blood supply?
Left ventricle
carry deoxygenated blood from the myocardium back to the right atrium
Coronary Veins
receives deoxygenated blood from the coronary veins and empties into the right atrium to return the blood into circulation
Coronary Sinus
the ability of cardiac muscle to create its own contractions and relaxations through its internal conduction system
Autorhythmic
drugs that decrease transmission of the electrical impulse through the AV node cells
Calcium Channel Blockers
Explain the general pathway for blood flow through the heart
- Right atrium
- Right ventricle
- Lungs
- Left atrium
- Left ventricle
- Body
Explain the detailed pathway for blood flow through the heart
- Vena cava
- Right atrium
- Tricuspid valve
- Right ventricle
- Pulmonary valve
- Pulmonary artery
- Pulmonary circulation
- Pulmonary vein
- Left atrium
- Mitral valve
- Left ventricle
- Aortic valve
- Aorta
- Systemic circulation
- Arteries
- Capillaries
- Veins
the large vein that brings deoxygenated blood from systemic circulation to the heart
Vena Cava
What are the 2 subdivisions of the vena cava
- Caudal Vena Cava
- Cranial Vena Cava
the vein that brings blood from the abdomen to the right atrium
Caudal Vena Cava
the vein that brings blood from the head to the right atrium
Cranial Vena Cava
one cycle of atrial and ventricular contraction and relaxation that produces 1 heartbeat
Cardiac Cycle
List the 4 structures of the primary cardiac conduction system
- Sinoatrial Node
- Atrioventricular node
- Bundle of His
- Purkinje Fibers
an area of cardiac muscle cells that automatically generate the impulses needed to trigger each heartbeat and is located in the wall of the right atrium
Sinoatrial (SA) Node
Explain the contraction of cardiac muscle cell
- Cardiac muscle cells are polarized (outside cell (Na+ and Ca+2 / inside cell K+)
- Na+ and Ca+2 ions move into the cell > cell is now depolarized > cell contracts
- K+ ions move out of the cell > polarity restored
- Ions are pumped back to the original locations > cell is repolarized
Explain the general cardiac muscle impulse pathway
- Base
- Apex
- Base
Explain the detailed cardiac muscle impulse pathway
- SA node (in right atrium)
- Across both atria
- AV node (in atrioventricular septum)
- Delay at AV node (allows atria to complete contraction before ventricles do)
- Bundle of His
- Apex
- Purkinje Fibers
- Right + left ventricular myocardium
the contraction of the myocardium which causes a chamber to empty itself of blood
Systole
When cardiac muscle cells are depolarized in the cardiac cycle
Systole
the relaxation of the myocardium which allows a chamber to fill with blood again
Disatole
When cardiac muscle cells are repolarized in the cardiac cycle
Diastole
Atrial systole + Ventricle diastole =
Atrial systole + Ventricle diastole = blood flows from atria to the ventricles
Ventricular systole + Atrial diastole =
Ventricular systole + Atrial diastole = blood ejects from ventricles + atria fill again
the sound produced when the tricuspid and mitral valves snap shut after atrial systole
“Lub”
the sound produced when the pulmonary and aortic valves snap shut after ventricular systole
“Dub”
the sound produced by turbulence in blood flow and sounds like a whooshing sound instead of a lub or a dub
Murmur
a heart condition where one or more cardiac valves don’t close all the way and produces a murmur sound due to blood backflowing abnormally into a chamber
Valvular Insufficiency
the result when the mitral valve doesn’t close all the way when the left ventricle begins systole and some of the blood backflows into the left atrium
Mitral Valve Insufficiency
a heart condition where any one or more of the cardiac valves don’t open all the way and produces a murmur sound due to blood flowing through a partially open valve
Valvular Stenosis
results when the mitral valve doesn’t open entirely during left atrial systole and some of the blood remains in the left atrium
Mitral Valve Stenosis
the volume of blood that is ejected out of the left ventricle over a unit of time (usually 1 minute)
Cardiac Output (CO)
What is the formula to determine cardiac output?
Cardiac Output (CO) = Stroke Volume (SV) x Heart Rate (HR)
What 2 factors determine cardiac output?
- Stroke Volume (Systolic Discharge)
- Heart Rate
the volume of blood ejected from the left ventricle during one contraction or systole and represents the strength of the heartbeat
Stroke Volume (Systolic Discharge)
What 3 factors determine stroke volume?
- Preload
- Afterload
- Length of Cardiac Muscle Cells
the volume of blood the ventricle receives from the atrium
Preload
the physical resistance presented by the artery the ventricle is ejecting blood into
Afterload
the number of times the ventricle contracts or beats in 1 minutes
Heart Rate
What is the normal heart rate / pulse rate for:
Dogs
Cats
Horses
Dogs = 70-120
Cats = 120-140
Horses = 28-40
List the 3 layers of the walls in arteries and veins
- Endothelium
- Middle Layer
- Outer Layer
the layer in the walls of arteries and veins that lines the lumen and is smooth so blood can flow through the vessel with little to no friction
Endothelium
the layer in the walls of arteries and veins made of smooth muscle, elastic fibers, or both in order to control vasodilation and provide elasticity to the vessel
Middle Layer
the layer in the walls of arteries and veins composed of fibrous connective tissue and collagen fibers in order to prevent the wall from tearing, anchor the vessels, and keep the lumen of the vessel pulled open
Outer Layer
What are the 2 types of ateries?
- Elastic Arteries
- Muscular Arteries
arteries found closest to the heart because they can stretch and recoil without damage
Elastic Arteries
arteries located farther from the heart, direct blood to specific organs and tissues, and branch into arterioles
Muscular Arteries
tiny blood vessels whose small diameter and contraction abilities via the autonomic nervous system produce blood flow resistance to help maintain blood pressure, as well as branch into capillaries
Arterioles
the largest elastic artery in the body
Aorta
the arteries that supply the legs and tail
Iliac Arteries
the artery that branches off the iliac arteries and travels distally along the medial surface of the rear leg
Femoral Artery
the artery that supplies blood to the heart muscle
Coronary Artery
the arteries that branch off the aorta and give rise to the carotid arteries
Subclavian Arteries
the arteries that supply blood to the head and neck
Carotid Arteries
the artery that supplies blood to the stomach, spleen, and liver
Coeliac (Celiac) Artery
the arteries that supply blood to the intestines
Cranial and Caudal Mesenteric Arteries
the arteries that supply blood to the kidneys
Renal Arteries
microscopic blood vessels that connect arteries to veins and are where exchanges of gases and nutrients take place
Capillaries
tiny blood vessels that allow deoxygenated blood to return from capillary beds to the veins
Venules
the veins that carry blood from the head to the cranial vena cava
Jugular Veins
the largest vein in the body
Vena Cava
the veins of the intestinal system that join together to form the portal vein
Mesenteric Vein System
the juncture of the mesenteric veins that empties into the liver where blood is filtered and detoxified
Portal Vein
the vein that drains the liver and empties into the caudal vena cava
Hepatic Vein
the vein on the anterior surface of the forelimbs
Cephalic Vein
the vein on the lateral surface of the hind limbs just proximal to the hock
Lateral Saphenous Vein
the vein on the medical surface of the femur
Medial Saphenous Vein
the blood vessel that carries carbon dioxide and wastes and picks up oxygen and nutrients for the fetus
Umbilical Artery
the blood vessel that carries oxygenated blood from the placenta into the fetus
Umbilical Vein
List the 2 structures that allow fetal blood to bypass the lung tissue
- Foramen Ovale
- Ductus Arteriosus
the fetal circulation structure located between the left and right atria that permits oxygenated fetal blood to bypass lung tissue
Foramen Ovale
the fetal circulation structure located between the pulmonary artery and the aorta that permits oxygenated fetal blood to bypass lung tissue
Ductus Arteriosus
a condition in which the fetal-bypass structure between the pulmonary artery and the aorta fails to close in the newborn, results in an audible murmur and inadequate blood oxygenation
Patent Ductus Arteriosus (PDA)
the rate of alternating stretching and recoiling of the elastic fibers in an artery as blood passes through it with each heartbeat and is used to evaluate the strength and regularity of the pulsations
Pulse
the wave of increased pressure started by ventricular systole radiating from the semilunar valves over the arterial system
Pulse Wave
Common Pulse Points for:
Cat
Dog
Cow
Horse
Sheep
Goat
Piglet
Pig
Cat - femoral artery
Dog - femoral artery
Cow - coccygeal artery + facial artery
Horse - mandibular artery + posterior digital artery
Sheep - femoral artery
Goat - femoral artery
Piglet - femoral artery
Pig - coccygeal artery
the measure of the amount of pressure flowing blood exerts on arterial walls
Blood Pressure
Blood pressure is dependent on interactions between what 4 things?
- HR
- Stroke Volume
- Diameter + elasticity of arteries
- Total blood volume
the pressure measurement produced by the ejection of blood from the left ventricle into systemic circulation through the aorta
Systolic BP
Higher # on BP reading
Systolic BP
the measurement of pressure remaining in an artery during left ventricular relaxation
Diastolic BP
Lower # on BP reading
Diastolic BP
the average pressure on an artery during one cardiac cycle and can be used when monitoring an anesthetized animal as an indication of tissue perfusion
Mean Arterial Pressure (MAP)
What are the 2 methods to measure BP?
- Oscillometric Method
- Doppler Ultrasound Method
the blood pressure measurement method that measures systolic BP, diastolic BP, mean arterial pressure, and heart rate
Osciollometric Method
the blood pressure measurement method that measures systolic BP
Doppler Ultrasound Method
Tests that monitor the cardiovascular system - evaluates:
- Heart rate and rhythm
- Detect heart murmurs
Auscultation of the thorax
Tests that monitory the cardiovascular system - evaluates:
- Rate, regularity, and strength of pulse
Peripheral Artery Palpation
Tests that monitor the cardiovascular system - evaluates:
- Cardiac output
Measurement of Arterial BP
Tests that monitor the cardiovascular system - evaluates:
- Size and position of the heart
Thoracic Radiography
Tests that monitory the cardiovascular system - evaluates:
- Electrical activity of the heart
Electrocardiography
Tests that monitory the cardiovascular system - evaluates:
- Size, shape, movement of heart structures
Echocardiography
a procedure that records electrical signals in the heart to help diagnose heart attacks and arrythmias
Electrocardiography
ECG or EKG
Electrocardiogram
the time it takes the wave of depolarization (contractions) to travel from the SA node through the atria and corresponds to the mechanical activity of atrial contractions in a normal animal
P wave
the time of ventricular depolarization (contraction) and corresponds to the mechanical activity of ventricular contraction
QRS complex
corresponds to the depolarization of the interventricular septum
Q wave
corresponds to the depolarization of the main mass of the ventricles and is the largest wave
R wave
corresponds to the final part depolarization of the ventricles near the base of the heart
S wave
the time of ventricular repolarization (relaxation) and corresponds to the time taken by the ventricles to get ready for the next contraction by refilling with blood from the atria
T wave
a procedure that uses ultrasound to bounce sound waves off parts of the heart in order to evaluate the size of the heart chambers, thickness of the myocardium, functioning of the valves, and overall movement of the heart and its parts
Echocardiography (ECHO or Cardiac Ultrasound)
an ultrasound procedure that measures blood flow through the heart and adds color to the image in order to evaluate for valvular stenosis and insufficiency
Doppler Echocardiography
Venipuncture site:
Runs between the elbow and carpus on the cranio-medial aspect of the forearm
Cephalic Vein
Venipuncture site:
Runs along the medial aspect of the hind limb between the groin and the hock
Femoral vein
Venipuncture site:
Runs along the lateral aspect of the hind limb from the cranial aspect of the leg just above the hock to the caudal aspect just below the stifle
Saphenous Vein
Venipuncture site:
Travel in muscular grooves along the ventral aspect of each side of the neck, from mandible to shoulder
Jugular Vein
Venipuncture site:
Travels along the ventral aspect of each side of the abdomen from the udder to about the level of the sternum
Superficial Caudal Epigastric Vein (Milk Vein)
Venipuncture site:
Runs along the ventral midline of the tail
Coccygeal Vein
the most cranial stomach compartment in cattle that rests directly behind the heart
Reticulum
inflammation and infection of the reticulum and abdominal cavity in cattle caused by puncture of the reticulum wall by a foreign object
Reticuloperitonitis (Hardware Disease)
an infection of the pericardium that usually progresses to heart failure and death
Septic Pericarditis
excess fluid accumulation in the pericardial sac
Pericardial Effusion
diseases or conditions that occur spontaneously with no known cause
Idiopathic
the condition in which the pericardial space is overfilled with fluid and the heart is unable to expand normally between contractions
Cardiac Tamponade
the manual resetting of the electrical conduction system in the heart
Defibrillation
electrical heart stimulation located outside the sinoatrial node that results in lost contraction synchronization
Ectopic Pacemakers
meaning out of place
Ectopic
a condition in which heart muscle cells in different areas contract independently of one another and all coordinated pumping in the ventricles is lost
Ventricular Fibrillation
a condition that occurs when the pumping ability of the heart decreases, usually due to disease of the heart muscle or a valve malfunction that restricts forward flow of blood through a valve or allows a backward flow
Congestive Heart Failure (CHF)
fluid in the abdomen
Ascites
excess fluid in the tissues
Edema
Type of CHF characterized by
- Blood returning from systemic circulation can no longer move through the right heart as quickly
- Causes increased BP in systemic circulation > ascites + edemas
Right-Side Congestive Heart Failure
Type of CHF characterized by:
- Venous return from the lungs is decreased
- Causes pulmonary edema > interferes with respiratory function
Left-Side Congestive Heart Failure