how does the auricular surface look like?
how does the atrial surface look like?
what is the pericardium?
Fluid filled sac providing protection against friction
what are the 2 tissue layers of the pericardium?
- 1. Visceral pericardium → covers surface of the heart
- 2. Parietal pericardium → covering the inner surface of the parietal sac
what is the paricardial cavity?
- Slender gap between the parietal and the visceral surfaces
- Filled with fluid to reduce friction between layers as the heart pumps
what is the epicardium?
Outer layer of the heart wall (visceral layer)
what is the myocardium?
- Muscle tissue of the heart
- Located below the pericardium
- Most of the myocardium is located in the lower 2 chambers of the heart called the ventricles
what is the endocardium?
Inner layer of the heart
what are the auricles?
Earlike appendage of each atrium of the heart (pectinate muscle)
what is the atria?
2 superior chambers of the heart, receiving their blood
what are the ventricles?
- 2 lower chambers of the heart
- "pumping chambers"
- ID: chordae tendinae, papillary muscles, trabeculae carnea muscles (fleshy pillars)
what are the valves of the heart?
Mechanical devices that permit the flow of blood in 1 direction only
what are the 4 valves of the heart?
There are 2 types:
- 1. Atrioventricular Valve
- Right AV → tricuspid valve
- Left AV → bicuspid or mitral valve
- 2. Semilunar Valve
- Pulmonary trunk → pulmonary semilunar v.
- Aorta → aortic semilunar v.
what is the coronary artery?
- The blood vessel lies in the groove on the front of the heart
- It branches over the front and the back side of the heart to supply fresh blood with oxygen and nutrients to the heart muscle itself
what does the left coronary artery do?
It leaves the right sinus and supplies blood into RA and RV
what does the right coronary artery do?
- It leaves the left sinus
- Short branch splits into 2 arteries:
- 1. Circumflex artery (coronary grove)
- 2. Paraconal artery (along the paraconal inter ventricular groove)
what is the great cardiac vein?
Blood is returned to right atrium via the coronary sinus
what is the pulmonary artery?
- Big blood vessel branches
- Carries blood to the lungs to receive oxygen
- Can be found curving out of the right ventricle (upper chamber to your left)
what is the aorta?
- Major vessel located near the right atria and just behind the pulmonary trunk going to the lungs
- The curved part is know as the aortic archBranching from the aortic arch is a large artery that supplies blood to the upper body (Brachiocephalic artery)
what are the pulmonary veins?
Vessels that return oxygenated blood from the right and left lungs to the left atrium (upper chamber on your right)
what are the inferior and superior vena cava?
- These 2 blood vessels are located on your left of the heart and connect to the right atrium (upper chamber on your left)
- Deoxygenated blood enters the body through these vessels into the right receiving chamber
- Those vessels do not contain valves to control blood flow
what is the chordae tendon?
- Long fibres of connective tissue
- Are attached to the papillary muscles of the heart
what is the trabeculae carneae?
what is the conduction system system for?
Cardiac muscle with different functions (conduction) then ordinary cardiac m. (contraction)
what is the sinoatrial node (SA)?
- Self-excitable cells
- Contracting without any signal from the nervous system
what is the atrioventricular node?
what is the atrioventricular bundle?
what regulates the heart?
- Regulated by ANS
- BUT only to increase ↑ or decrease ↓ heart rate
what is an EGC?
- Electrocardiogram: graphic record of the hearts electrical activity (conduction impulse)
- Impulse conduction generates electrical currents in the heart, spread to tissue and to surface of the body
- It is NOT a record of the hearts contractions but the electrical events that precedes them
what is a Wiggers diagram?
standard diagram used in cardiac physiology
what are the 2 parts of the cardiac cycle?
- systole : contraction of the heart muscle
- diastole : relaxation of the heart muscle
when does the Atria contract?
While the ventricles contract
what is the pulse?
A wave of contraction transmitted through arteries
how does an ECG work?
- ECG wave consists of an isoelectric line (neutral) with positive and negative deflections
- ECG intervals and segments enable us to measure the timing of the different phases
how can we detect and record the difference of electrical potentials between the 2 points?
By using skin electrodes
what is the P wave?
depolarization of the AV nodes and the atria in response to SA node triggering
what is the QRS complex?
- depolarization of ventricles,
- depolarization of atria in response to SA node triggering
what is the T wave?
what is the PR segment?
Delay of the AV node to allow filling of the ventricles
what is the ST segment?
- Beginning of ventricle depolarization
- ventricular contraction
what is the TP interval?
what is a myocardial infraction?
- Blood supply to the heart is interrupted
- There is occulusion (blockage) of a coronary artery
- Caused by an artherioclerotic plaque detachment
- Results in Ischemia (restriction of blood supply)
- Oxygen shortage to heart tissue (death of myocites)
- If left untreated over time, it causes a infraction (Heart attack)
what is arteriosclerosis?
- Hardening of the arteries
- Causes hypertension
- Collection of lipids and macrophages in the Wall of arteries
what is artheriosclerotic plaque?
- Formation of plaque in an injured artery
- Inside the lumen
- Causes ↑ BP