Surface Anatomy of Heart Flashcards
What does the pericardiac sac consist of?
Fibrous part
Parietal layer
Serous layer
What does the fibrous part of the pericardial sac consist of?
Ligament to the stenum (sternopericardial ligament)
What happens to the ligament to the sternum?
It inferiorly blends with the diaphragm
What does the sternopericardial ligament do?
Holds the heart in place
What is the parietal layer?
The outer layer
What is the serous layer?
The inner layer
What does the serous layer attach to?
The heart and great vessels
How are the parietal and serous layers related?
It is one continuous layer that is reflected back on itself
What is found between the parietal and serous layers?
A thin layer of fluid
What does the thin layer of fluid between the parietal and serous layer do?
Gives a frictionless environment
What is the name of the nerves that supply the heart?
Phrenic nerves
What are the nerve roots of the phrenic nerves?
C3, 4, 5
What do the phrenic nerves supply?
Motor and sensory to the diaphragm
Sensory to the pericardium
What is the course of the phrenic nerves?
They descend anterior to the lungs, and then the right descents over the right atrium, and the left over the left atrium
What is the heart surrounded by?
Dual layered pericardium
Where does the heart lie?
Deep to the sternum, inferior to the great vessels, and superior to the diaphragm
What is the anterior pericardial surface attached to?
The posterior surface of the sternum, via the sternopericardiac ligaments
What is the inferior pericardial surface fused with?
The diaphragm
What consists the anterior surface of the heart?
Right atrium and ventricle
What consists the posterior surface of the heart?
Left atrium and ventricle
What is the left border of the heart?
Left ventricle
What is the inferior surface of the heart?
Right ventricle
What is the right border of the heart?
Right atrium
What are the blood vessels od the heart?
The coronary arteries and the cardiac veins
What do the blood vessels of the heart do?
Carry blood to and from most of the myocardium
Where to the coronary blood vessels run?
Across the surface of the heart, just deep to the epicardium, normally embedded in fat
What is the first branch of the aorta?
The coronary arteries
Where do the coronary arteries arise from?
From the left and right aortic sinuses
Where do the aortic sinuses arise from?
The root of the aorta, just superior to the aortic valve
Where do the aortic sinuses pass?
Around opposite sides of the pulmonary trunk
What does the right coronary artery supply?
The right atrium, SA and AV nodes, and posterior parts of the IVS
What course does the RCA take on the anterior surface of the heart?
In travels in the right atrioventricular groove, passing posteriorly between the right atrium and ventricle.
In then gives off the sinuatrial branch
It continues down the atrioventricular groove, and gives off right marginal branch
After giving off this branch, it turns to the left and continues in the atrioventricular groove to the posterior aspect of the heart
What % of people have a sinuatrial nodal branch?
60%
What does the sinuatrial nodal branch supply?
The SA node
What does the right marginal branch supply?
The right border of the heart
Where does the right marginal branch run?
Towards (but does not reach) the apex of the heart
What course does the RCA take on the posterior surface of the heart?
Gives rise to atrioventricular nodal branch
Then gives rise to the posterior interventricular branch
The terminal RCA then continues for a short distance in the posterior atrioventricular groove
Where does the RCA give rise to the atrioventricular nodal branch?
At the junction between the four heart chambers (the crux)
What does the atrioventricular nodal branch supply?
AV node
What % of people have a posterior interventricular branch?
67%
What does the posterior interventricular branch do?
Descends inbetween the ventricles, supplying adjacent areas of both ventricles and sending perforating interventricular septal branches into the interventricular septum
What does the left coronary artery supply?
Most of the left atrium and ventricle, IVS and AV bundles, may supply AV node
What course does the LCA take on the anterior surface of the heart?
In runs in the left atrioventricular groove, where it splits into two branches, the anterior interventricular artery (or left descending (LAD) artery) and the circumflex branch
What course does the anterior interventricular artery take?
Runs in anterior interventricular groove to the apex, where it turns around the inferior border of the heart and commonly anatomoses with the posterior interventricular artery
What does the anterior interventricular artery supply?
Adjacent parts of both ventricles, and the interventricular septum
How does the anterior interventricular artery supply the interventricular septum?
Via interventricular septal branches
What does the anterior interventricular branch give off in many people?
The diagonal artery
Where does the diagonal artery run?
Down the anterior surface of the heart
What course does the circumflex branch of the LCA take?
It follows the atrioventricular groove to the posterior surface of the heart
What branches from the circumflex artery?
The left marginal branch
SA branch
Where does the left marginal branch run?
Down the left margin of the heart
What does the left marginal branch supply?
The left ventricle
How does the circumflex artery terminate?
Most commonly in the AV groove
In one third of hearts, it continues to the posterior interventricular groove
What % of people have the SA branch from the circumflex artery?
40
What is the heart drained by?
Veins that empty into the coronary sinus, and partly by small veins that drain into the right atrium
What are the veins of the heart
Coronary sinus Great cardiac vein Middle cardiac vein Small cardiac vein Anterior cardiac veins
What is the main vein of the heart?
Coronary sinus
Where does the coronary sinus run?
From left to right in the posterior part of the atrioventricular groove
What is the main tributary of the coronary sinus?
The great cardiac vein
What is the first part of the great cardiac vein?
The anterior interventricular vein
Where does the anterior interventricular vein begin?
Near the apex of the heart
What course does the anterior interventricular vein take?
It ascends with the anterior IV branch of the LCA. It takes a left at the AV groove, and runs with the circumflex branch of the LCA to reach the coronary sinus
What does the middle cardiac vein accompany?
The posterior IV branch (usually from RCA)
What does the small cardiac vein accompany?
The right marginal branch of the RCA
What are the anterior cardiac veins?
Several small veins that begin over the anterior surface of the right ventricle
What course do the anterior cardiac veins take?
They cross over the AV groove, and usually end directly in the right atrium (i.e. not via the coronary sinus)