(2) Heart 2 - Keryn Reilly Flashcards
Right atrium
Receives all venous blood in the body
IVC, SVC and the coronary sinus
Musculi pectinati
Anterior portion of the right atrium/auricle
Muscular part that can contract
Crista terminalis
Ridge between the muscular portion (musculi pectinati) and the venous part of the right atrium
Fossa ovalis
Was the foramen ovale
Remnant of the embryological vessel
Trabeculae carnaea
The ventricular muscle wall itself
Does the contracting
Papillary muscles (anterior, posterior and septal)
Contract and pull the valve flaps to ensure they don’t get “blown out” under the high pressure
Problems with valves
Stenotic
Regurgitation
Moderator band (septomarginal trabecula)
Piece of muscular tissue that runs from the interventricular septum to the anterior wall of the RV
Important! Shortcut for impulses to reach the anterior part of the ventricle to ensure smooth, even co-ordinated contraction
Left atrium
Only part that can contract is the left auricle
Takes in a lot of veins
Conduction system of the heart
SA node –> AV node –> AV Bundle (Bundle of His) –> Right and left bundle branches –> Septomarginal trabecula (i.e. the moderator band) –> Purkinje fibers
Before the ventricles contract…
Papillary muscles contract prior (to pull on the valve leaflets)
The IV septum stiffens (as the LV is much stronger than the RV, it may blow out into the right side therefore a stiff septum stops this)
Right coronary artery infarction
Leads to arrhythmia (due to SA and AV node being damaged)
Left coronary artery infarction
Leads to pump failure
Cardiac plexus
Mixture of sympathetic (T1-T5) and parasympathetic fibers (vagus nerve)
Increased sympathetic activation
Increase heart rate, dilates your coronary vessels
