Lecture 22: Heart Gross Anatomy Flashcards
Mediastinum
Space between the pleural cavities
Phrenic nerve: Fiber type, roots, trajectory
GSE; C3, 4, 5; Through middle mediastinum, to the diaphragm
What vessels supply the diaphragm and pericardium?
Pericardiacophrenic arteries and veins
Artery is a branch of the internal thoracic artery
Vein drains into internal thoracic vein
What are the sacs of the pericardium?
There are 2:
- Outer fibrous sac (composed of fibrous pericaridum)
- Inner serous sac (composed of serous pericardium, with parietal and visceral layers, with a pericardial cavity in between)
components of inner serous sac
Serous pericardium of the 2 pericardium sacs; composed of an outer parietal layer, middle pericardial cavity, and inner visceral layer, which is aka epicaridum
What’s another name for the visceral layer of the pericardium’s inner serous sac?
Epicardium
3 layers of the wall of the heart
epicardium, myocardium (cardiac muscle), endocardium
What are sulci, where do you see them, what are they composed of?
A component of the epicardium that are grooves of adipose tissue on the surface of the heart (aka FAT!)
Demarcate the chambers of the heart on the heart’s surface
What do the (anterior/posterior) coronary sulci (sing: sulcus) demarcate?
2 atria from 2 ventricles
What do the anterior/posterior interventricular sulci (sing: sulcus) demarcate?
Right ventricle from Left ventricle
What are the coronary arteries/veins embedded?
In the adipose tissue of the sulci
What do coronary arteries do?
Supply myocardium with oxygen; their occlusion results in a heart attack
Major branches of the Right Coronary Artery
- Sinuatrial nodal branch (supplies the SA node)
- Marginal branch
- Atrioventricular nodal artery (supplies the AV node)
- Posterior interventricular branch
Major branches of the Left Coronary Artery
- Anterior interventricular branch (aka LAD, Left anterior descending artery)
- Circumflex branch
What is the first branch of the aorta?
Coronary arteries
What does left anterior descending artery (LAD) run along?
Anterior interventricular sulcus
It is known as the Interventricular branch, the Widow Maker because where heart attacks occur most often
Location/path of the Right coronary artery
Originates from right aortic sinus of the ascending aorta; descends in the coronary sulcus between RA and RV
Travels in the coronary sulcus to reach posterior surface of the heart; there it anastomoses with circumflex branch of left coronary artery
What runs within the coronary sulcus?
Right coronary artery, small cardiac vein, coronary sinus, circumflex branch of the left coronary artery
What is the right atrial branch?
Branch of the RCA
Supplies the SA node
Where does sinuatrial nodal branch supply come from?
60% from Right coronary artery; 40% from Left coronary artery
Atrioventricular nodal artery supply?
Branch of the posterior interventricular branch of the RCA; 80% supply to AV nodal artery from the RCA, 20% from the LCA
Wheres does the LAD run?
Anterior interoventricular sulcus
What does the Right coronary artery supply?
Right atrium
Right ventricle
Posterior part of the Left ventricle
Posterior part of the interventricular sulcus
What does the Left coronary artery supply?
Left atrium
Left ventricle
Variable amount of Right ventricle
Most of the interventricular sulcus
Right coronary artery dominance
Normal distribution pattern of the coronary arteries means a right dominant coronary artery (supplies to 70% of heart) because the posterior interventricular branch arises from the RCA, and it supplies much of the posterior wall of the LV
Left coronary artery dominance
Normally, LCA supplies only 15% of the heart
In hearts with left dominant coronary artery, posterior interventricular branch arises from enlarged circumflex branch –> supplies most of posterior wall of LV
What do coronary arteries do?
Supply myocardium with oxygen
What do cardiac veins do?
Remove metabolic waste products from the metabolic activity of the myocardium
What are the branches of the cardiac veins of the heart?
- Coronary sinus
- Great cardiac vein
- Middle cardiac vein
- Small cardiac vein
- Anterior cardiac vein
- Venae cordis minimae
What cardiac vein(s) drain into the coronary sinus / RA?
Great cardiac vein
Middle cardiac vein
Small cardiac vein
What cardiac vein(s) drain into the RA?
Anterior cardiac vein
What cardiac vein(s) drain into the RA chamber?
Venae cordis minimae