Week 2 EP Pressures Flashcards
What are the layers of the heart
- pericardium
- fibrous layer
- parietal pericardium
- visceral pericardium
- myocardium
What is the pericardium
Membrane that encloses the heart
Normal fluid cc’s in pericardial sac
20-50 cc’s of fluid
What are the 3 parts of the myocardium
- epicardium
- midwall
- endocardium
What are the directions for myocardial fibers
- epicardial have oblique fibers
- midwall has circumferential fibers
- endocardial has longitudinal fibers
What are the 2 branches of the left coronaries
- Left anterior descending (LAD)
- Left Circumflex
What parts of the heart do the left coronaries supply
- LAD supplies blood to anterior wall of LV, IVS, and apex
- LCX supplies blood to lateral and posterior portion of heart
What does the right coronary artery supply
RCA supplies blood to the RV and the inferior wall of LV
What are the 3 functions of cardiomyocytes
- Automaticity: allows the heart to beat on its own
- excitability: accept and respond to electrical impulses
- conductive: cells transfer electrical signals to other cells
- contractile: cells contract
(AECC
Where are cardiomyocytes found
They are found in the sinoatrial node
What are the 5 components of the electrical system of the heart
- Sinoatrial node
- Atrial intermodal pathway
- atrioventricular node
- Bundle of hiss
- purkinje fibers
Functions of the SA node
- Has the highest automaticity
- Native pacemaker of the heart
What branches make up the internodal pathways
- RA: anterior, middle, posterior
- LA: bachmanns bundle
Functions of the AV node
- Connects atria to ventricles electically
- slows impulse for .05 seconds to allow for ventricular filling
Function of purkinje fibers
Purkinje fibers penetrate into ventricular muscle and conduct action potentials creating ventricular contraction
