The Heart Flashcards
3 components of the pericardium
Inner parietal serous pericardium, middle fibrous pericardium and outer mediastinal pericardium
Where is the heart and pericardium located
In the middle part of the mediastinum, from the level of the 3rd and 6th rib
What forms the phrenicopericardial ligament
The continuation of the fibrous pericardium to the sternum and diaphragm
What is the parietal layer continuous with at the base of the heart
Visceral layer (epicardium)
Between the parietal and visceral serous pericardium is the…
Pericardial cavity
Where are the great vessels of the heart attached
On the dorsal base
The surface of the heart facing the left thoracic wall is the…
Auricular surface (the tips of the two auricles project on this side)
The surface of the heart facing the right thoracic wall is the…
Atrial surface
What/where is the coronary sulcus
It lies between between the atria and ventricles and contains the coronary vessels and fat
Obliquely traversing the auricular surface of the heart is the…
Paraconal interventricular sulcus
What does the paraconal interventricular sulcus contain
Paraconal interventricular branch of the left coronary artery
What does the subsinuosal interventricular sulucs contain
The terminal branch of the left coronary artery
What are inteventricuar sulci
Superficial separations of the right and left ventricles
The right atrium receives blood from…
The systemic veins and most of the blood from the heart itself
2 parts of the right atrium
Sinus venarum (main) and right auricle (blind cranial)
What are the 4 openings of the sinus venarum
Caudal vena cava (enters caudally), coronary sinus (venous return of most of blood from heart), cranial vena cava (enters dorsally cranially), right atrioventricular orifice (from the right atrium to right ventricle)
What is the dorsal medial wall of the sinus venarum
Interatrial septum
What is the function of the intervenous tubercle
It diverts the inflowing blood from the two caval veins toward the right atrioventricular tubercle
What is the foramen ovale
It is an opening in the fossa ovalis in the fetus that allows blood to flow from the right to left atrium
Right auricle
Blind, ear-shaped pouch of the right atrium that faces cranially and to the left
What are pecinate muscles
They strengthen the internal wall of the right auricle
The greater part of the base of the right ventricle communicates with the right atrium through the…
Atrioventricular orifice (contains the atrioventricular valve)
What are the 2 parts of the atrioventricular valve in the dog
Parietal cusp and septal cusp (right also has angular)
Chordae tendineae
Attached septal cusp flaps to septal wall of the ventricle
Papillary muscles
Attach the chordae tendineae to the septal wall
Trabeculae carneae
Muscular irregularities of the interior of the ventricular walls
Trabecular septomarginalis
Muscular strand that extends across the lumen of the ventricle from the septal to parietal wall
The right ventricle passes across the cranial surface of the heart and terminates as the…
Conus arteriosus
The conus arteriosus gives rise to…
Pulmonary trunk
At the junction between the right ventricle and the pulmonary trunk is the…
Pulmonary valve
The pulmonary valve consists of…
3 semilunar cusps
The pulmonary valve bifurcates into…
Right and left pulmonary arteries
How many openings mark the entrance of the pulmonary veins into the left atrium
5-6
What is the valve of the foramen ovale
A remnant of the passage for the blood from the right atrium to the left atrium in the fetus
What is different about the atrioventricular valve cusps in the right and left atrioventricular valves
The division of the cusps is indistinct in the left, the right has 3 cusps (tricuspid)
What forms a connection between the aorta and pulmonary trunk
Ligamentum arteriosum
Behind each cusp of the aortic valve, the aorta is slightly expanded to form…
The sinus of the aorta
What 2 arteries leave the sinus of the aorta
Right and left coronary artery
What does the left coronary artery terminate in
Circumflex branch and paraconal interventricular branch
Coronary sinus
Dilated terminal end of the great cardiac vein
Great cardiac vein
Returns blood supplied to the heart by the left coronary artery
2 divisions of the right atrium
Sinus venarum (atrium proper) and right auricle
What are the structures in the ventricles
Chordae tendinae, papillary muscles, trabeculae carneae, trabecula septomarginalis
The right AV is…
Tricuspid
The left AV is…
Bicuspid (mitral valve)
What supplies blood to the right atrium
Cranial/caudal vena cava, azygos, coronary sinus
The R/L coronary artery originate from…
The aortic sinus
The right coronary artery supplies…
The RA and RV
The left coronary artery branches into…
Circumflex (coronary groove) and paraconal interventricular (auricular surface) artery
What is the continuation of left coronary artery on the atrial surface
Subsinusoal interventricular artery
What are the 3 parts of the coronary sinus
Great, middle and small cardiac vein
Sinoatrial node function and location
Pacemaker, located in RA wall near superior vena cava
Atrioventricular node location
Located in right atrium along the lower part of interatrial septum
Bundle of His location
Cardiac fibers originating in the AV node, extend down septum
When does the Bundle of His become the purkinje fibers
At the lateral walls of the ventricles and papillary muscles
In general, the larger the species, the ___ the rate of SA node discharge
Slower
Respiratory sinus arrythmia
When the heart rate speeds up inspiration (decrease in vagal activity) and slows down during expiration (increase in vagal activity)
Foramen ovale function and name in the adult
Lets blood enter from RA to LA and bypass pulmonary circulation; Fossa ovalis
Ductus arteriosus function and name in adult
Connect pulmonary artery to aortic arch; Ligamentum arteriosum
Ductus venosus function and name in the adult
Shunts portion of left umbilical vein blood flow to descending vena cava, allowing oxygenated blood to bypass the liver; Ligamentum venosum
