Surfaces of the heart:
1. Anterior (Sternocostal)
3. Right pulmonary surface
4. Left pulmonary surface
5. Inferior surface
1. Right ventricle
2. Base of heart = LA and some RA
3. Right atria
4. Left ventricle
5. Left and right ventricles
Base vs. Apex of Heart
1. Structures included
2. Point of Maximum Impulse (PMI)
1. Base: top of heart & posterior (LA and some RA)
Apex = bottom & anterior (Left ventricle)
2. Apex deep to 5th intercostal space at midclavicular line
PMI = Apex (Left ventricle)
Diastole vs. Systole
What happens with ventricle and energy
Diastole: Ventricular filling (passive flow down)
Systole: Ventricular emptying (energy required)
What prevents prolapse of blood during systole?
Papillary muscles contract to hold valves closed during chordae tendinae
What are the two external grooves of the heart?
What vessels do these grooves contain?
Coronary sulcus: between atria and ventricles (right coronary artery & circumflex artery)
Interventricular sulcus: between left and right ventricles (Contain the LAD)
What are the two internal divisions of the heart?
Interatrial septum: separate left and right atria
Interventricular septum: separate left and right ventricles
What are the two parts of the interventricular septum?
Membranous and Muscular
1. Which vessels go in
2. What is the rough section called?
1. SVC, IVC, and coronary sinus (inferior)
2. pectinate muscle
What is the crista terminalis?
Smooth muscle ridge that divides muscle in right atrium
Anterior: rough pectinate muscles from primitive atrium
Posterior: smooth parts of the right atrium (dervied from sinus venosus)
Identify parts of right ventricle
What vessels go into left atrium?
4 pulmonary veins (2 from each lung)
What is the rough muscle in the left ventricle called?
1. Two types
2. How does it close
1. Tricuspid (between RA and RV) and Biscuspid=mitral (between LA and LV)
2. At Systole: Close when papillary muscles contract to tighten chordinae tendinae
1. Two types
2. How do they close
1. Pulmonary (RV to pulmonary trunk) and aortic valve (LV to aorta)
2. Close passively when the 3 sinuses are filled and came together at nodules during backflow
When do the coronary arteries fill?
During ventricular relaxation: Sinus contains two coronary artery openings
Right coronary artery
1. Where does it arise
2. Four branches and what they supply
3. How is size determined
1. Coronary sulcus (RA and RV)
sinoatrial nodal artery = SA node
marginal artery = right ventricle
posterior interventricular artery
AV nodal branch (small) = AV node
3. Right dominant system means larger right coronary artery
Left coronary artery
1. Where does it arise
2. Two branches and what they supply
1. Pulmonary trunk
a) Anterior interventricular artery (LAD) = left ventricle and AV bundle
b) Circumflex artery = part of left ventricle
What is an AV block? How can you tell from an ECG? What can cause it
1. desynchronization of atria in relation to ventricles
2. wide QRS complex
3. coronary artery disease
Great Cardiac vein, Middle Cardiac Vein, and Small Cardiac vein
1. Where do they travel and which artery does it travel with?
1. Great cardiac vein (apex of the heart): anterior interventricular sulcus with LAD
2. Middle cardiac vein: posterior interventricular sulcus with posterior interventricular artery
3. Small cardiac vein: coronary sulcus with marginal artery
Which cardiac vein transmits blood from the right ventricle to the right atrium (does not use the coronary sinus)?
Anterior cardiac veins
What is the coronary sinus?
Termination of almost all cardiac veins (great, middle, and small, but not anterior)
Transfers blood from myocardium to the right atrium
What are the layers of the heart?
Pericardium (Fibrous) -> Epicardium (aka serous pericardium) -> myocardium (cardiac muscle) -> endocardium
1. Where is it
2. Sympathethic innervation
3. Parasympathetic innervation
1. Surrounds aortic arch and tracheal bifurcation
2. Sympathetic: cardiac nerves (lateral horn of T1-5) go to cardiac plexus
3. Parasym: vagus nerve (CN X) to parasympathetic ganglia (in cardiac plexus or chest wall)
What are the visceral afferent nerves in the cardiac plexus?
1. Cardiac nerves = Pain fibers (ischemia) to T1-4
2. Vagus nerve: Reflex fibers (chemo and baro-receptors) to brainstem
What is referred pain?
Visceral sensation misinterpreted as somatic sensation
Pain from heart felt in the skin of chest and left arm
Heart conduction pathway
Where does the bundle of his start?
starts at membranous part of the intraventicular septum
Transverse Pericardial sinus
1. Where is it located?
2. What does it separate?
3. Why is it useful?
1. Posteriorly to the ascending aorta and pulmonary trunk.
Anteriorly to the superior vena cava.
Superior to the left atrium.
2. separates the arterial vessels (aorta, pulmonary trunk) and the venous vessels (superior vena cava, pulmonary veins) of the heart
3. used to identify and subsequently ligate the arteriesof the heart during coronary artery bypass grafting
What does each cardiac artery supply?
What is rough muscle in atria called? Ventricle?
Atria: Pectinate muscles