Cardiovascular System Flashcards
What are the functions of the cardiovascular system?
Transportation (respiratory, nutrients, excretory)
Protection
Regulation
Blood-vascular system
What makes up the blood vascular system ?
Heart
Arterial circulation
Venous circulation
Lymphatic circulation
Heart
4-chambered
Pair of atria in the craniodorsal portion
Pair of ventricles in the caudoventral position
Base and Apex
Where does the heart lie?
Between 3rd- 6th ribs
What structures are lateral to the heart?
Chest wall
Lungs
Phrenic nerve
What structures are cranial to the heart?
Thymus
Lungs
What structures are caudal to the heart?
Diaphragm
Liver
Stomach
Abdominal viscera
Coronary groove/ sulcus
Separates the thin walled atria from the ventricles
Annulus Fibrosis
Fibrous skeleton
Separates atria and ventricles physically and physiologically so they won’t contract at the same time
Separates and anchors the valves
What may the annulus fibrosis do in cows?
May ossify to give os cordis
Lymphatic system
Lymph vessels and lymph nodes (filters) necessary for balance of fluid flow
Arteries
Vessels that carry blood away from the heart toward a tissue mass
Arterioles
Arteries branching until reaching sizes less than 100 um or less in diameter
Capillaries
Arteries that branch until they are 10 um or less
Where gases, nutrients and wastes are exchanged between the bloodstream and tissue cells
Venules
Leave the capillary beds and connect to veins
Intima
Inner surface of the vessel
What is venous circulation maintained by?
Negative pressure
What are the superficial/ palpable lymph nodes in dogs ?
Mandibular
Superficial cervical
Axillary
Superficial inguinal
Popliteal
Pumps of the heart
Somatic (left, high pressure)
Pulmonary pump (right, low pressure)
Blood circulation
- Cr. and cd. vena cava takes unoxygenated blood
- Right atrium receives blood and sends it though the AV (tricuspid) valve
- Right ventricle receives, pumps it’s through pulmonic valve
- Pulmonary trunk receives and gives to lungs via r. and l. arteries
- L. atrium gets blood from lungs via pulmonary veins
- L. AV valve sends blood to l. ventricle
- L. ventricle pumps blood through aortic valve
- Aorta receives sends blood to body
What is blood flow dependent on?
Right and left AV valves
Pulmonic and Aortic valves
Why do atrioventricular valves close?
Closes to prevent back flow of blood into the atria upon systole (contraction)
Why do atrioventricular valves open?
To allow blood entering the atria to splash downward into the ventricles to fill them during diastole (relaxation)
What are the 3 subcompartments of the right atrium?
Sinus venarum cavarum
Right auricle
Coronary sinus
Coronary Sinus
Point where all great coronary venous circulation terminates
(Hole cd. Of heart)
Fossa ovalis
Adult remnant of fetal foramen ovale
(Shallow hole, not really seen)
What makes up the right ventricle
Papillary muscles
Chordinae tendinae
Trabeculae septomarginalis
Trabeculae carnae
Conus arteriosus
Empties via pulmonic valve into pulmonary trunk
(Space my pulmonary valve)
What does the chordae tendinae and papillary muscles so?
The contract during systole and keep AV valves from averting into the atria when they close
Coronary Circulation
Circulation of blood in blood vessels that supply the heart
Heart feeds itself first
15% of output
Heart characteristics
Striated
Actin and myosin
Centrally located nuclei
Branched fibers
Involuntary (autonomic)
What does the sympathetic nervous system do to the heart?
Speeds up the heart rate and increase contractile force (parasympathetic is opposite)
Purkinje system
Makes up conduction system of heart
Increased sodium permeability
Initiates it’s own contraction and intervals
Sinoatrial node (pacemaker)
Initiation center
Located in r. atrial wall
Most sodium-permeable
Fires first
What are the first branches of the aorta
L. and r. coronary arteries
Why are the 3 branches of the left coronary artery?
Paraconal
Circumflex
Subsinosal
Great cardiac vein
Opens into r. atrium via coronary sinus
Thebesian foramen
Lesser veins
Open directly into all 4 heart chambers
Coronary by-pass surgery
Corrects blocked vessels
Prosthesis of a saphenous vein
Grafted to ascending aorta and distal to the clogged artery
Layers of the fibroserous membranes of the heart (out to in)
- Pericardial parietal pleura
- Fibrous pericardium
- Parietal serous pericardium
- Epicardium
What does the pericardial cavity house?
1 cc of pericardial fluid
Pericardial sac layers (out to in)
- Pericardial pleura
- Fibrous pericardium
- Parietal serous pericardium
ECG
Evaluates the electrical flow of cardiac conduction system and the efficiency of atrial ventricular contraction
Cardiac Auscultation
Puncta maxima (PMI)
Maximal points of intensity for auscultation of the heart valves over the thoracic wall
Cardiac auscultation location for left chest
PAM 345
1. Pulmonic valve: 3rd space @ costochondral junction
2. Aortic valve: 4th space @ shoulder
3. Left AV: 5th space along sternal border
Cardiac auscultation location for right chest
PAM 345 R4
Right AV: 4th space above costochondral junction
Placenta
Where the mother provides baby with gas exchange, nutrients and takes care of waste products
Classified as zonary
Hepatic-Portal Circulation
Venous drainage from the digestive viscera which enter the liver
Blood filters and re-enter the systemic circulation
Blood from the gut area
Goes in the portal vein to the liver to be filtered and if the toxin is not removed it’s not good blood
What are the 2 capillary sets for portal circulation?
Villi (GI)
Sinusoid (liver)
What has the closest exchange to humans?
Primates
What are the 3 layers of the placenta?
Choroid
Allantois
Amnion
Fetal Circulation
- Oxygen and nutrient rich blood enter fetal body via umbilical veins
- @ liver umbilical vein passes through parenchyma as ductus venous
- Blood enters cd. vena cava and travels to r. atrium
- 60% passing foramen ovale into l. atrium, 40% into r. ventricle
- Through FO into l. atrium –> to l. ventricle -> ascending aorta
- R. ventricle blood is ejected passing ductus arteriosus –> descending aorta
Fetus circulation remnants
- Umbilical vein: round ligament of liver
- Ductus venosus: ligamentum venosum
- Foramen ovale: Fossa Ovalis
4.Ductus arteriosus: ligamentum arteriosum - Umbilival arteries: round ligament of the bladder
Ampulla
Site for fertilization
Isthmus
Conveys the embryo to the uterus
Uretotubal junction
Papilla
