Cardiac Anatomy Flashcards
How many layers does the pericardium have?
3 Fibrous Parietal Visceral
Pericardial collections may be secondary to?
Surgery/trauma
Inflammation (amyloidosis/viral/ uraemia/drugs)
Fibrous pericardium limits size of sac. Compression of heart with fluid leads to what?
Becks Triad
Raised JVP
Low BP
Muffled heart sounds
Pulses paradoxus >10mmg on inspiration
Shock
Low cardiac output
Posterior surface of the heart
LA and 4 pulmonary veins
Lateral border of the heart
LV
Plus most of inferior, lateral and anterior
Inferior border of the heart?
RV (one third inferior surface plus most of anterior)
Right border consists of?
RA and Vena Cava
Cardio thoracic ratio should be
<50%
Max transverse diameter of heart v max internal thorax diameter
Misleading if pregnant/obese or AP
Coronary sinus and IVC and SVC drain into where?
RA
RV muscle is important for what?
Trabeculated and so carries conduction
Tricuspid valve lies where?
RA-RV 3 cusps septal/inf/ant attached to the AV ring
Patent foramen ovale is where?
LA lies directly behind the RA. 15% patent demonstrated.
Where do the 4 pulmonary veins drain?
Posterior wall LA
Mitral valve lies where?
LA-LV 2 leaflets
How thick is the LV wall?
3-4x RV wall papillary muscles important for strength.
Cardiac action potential are generated by what and where?
Non contractile cardiac myocytes at SA node in superior right atrium
SA node blood supply?
RCA in 65%
AV node function is what?
To slow conduction of AP to ventricles. AV rings insulate the atria from the ventricles.
Abnormal pathways = reentrant tachycardia
Supplies by RCA in 80%
Aortic sinus give rise to what?
2 coronary arteries
LAD territory
Anterior
Coronary veins drain where?
Right atrium
Majority of venous blood drains from where to where?
Coronary sinus made up of great small and middle and posterior cardiac veins
Small veins drain directly into the chambers (thebesian)
Name the nerve supply to the heart?
Parasympathetic - vagus recurrent laryngeal
SA and AV node supply
Reduces rate and contractility and constricts CA
Sympathetic - T1-4 lateral horns. Cardioacceleratory. Pain fibres travel with sympathetic nerves which join spinal nerves
IJV pathway
Jugular foramen to subclavian vein
