Cardiology anatomy Flashcards
What are the 2 layers of the pericardium?
Fibrous and serous
What is the fibrous pericardium continuous with?
Central tendon of the diaphragm
Which layer of the pericardium is the tough, external layer?
Fibrous pericardium
What is the purpose of the fibrous pericardium being non-distensible?
Rigid structure prevents rapid over-filling of the heart.
What are the 2 subdivisions of the serous pericardium?
Outer parietal layer and inner visceral layer
What is the internal visceral layer also known as?
Epicardium
The outer parietal layer lines what?
The internal surface of the fibrous pericardium
The inner visceral layer forms what?
The outer layer of the heart
Where is the pericardial cavity?
Between the outer parietal and inner visceral layers of the serous cavity
What is the function of the serous fluid within the pericardial cavity?
Minimises friction generated by the heart as it contracts.
What are the 4 main functions of the pericardium?
Fixes the heart
Prevents overfilling
Lubrication
Protection from infection
What is the innervation of the pericardium?
C3 - C5 (why you get shoulder pain with pericarditis)
What is the order of the layers of the pericardium from most external to most internal?
Fibrous layer
Parietal layer
Serous fluid
Visceral layer
Where is the SAN located?
Upper wall of right atrium at the junction where the superior vena cava enters.
What does the sympathetic nervous system do to the firing rate of the SAN?
Increases firing rate = increased HR
What does the parasympathetic nervous system do to the firing rate of the SAN?
Decreases firing rate = decreased HR
Where is the AVN located?
Within AV septum, near the opening of the coronary sinus
Why does the AVN delay impulses by ~120miliseconds?
To ensure the atria have enough time to fully eject blood into the ventricles before ventricular systole
What is the standard approach for pericardiocentesis?
Subxiphoid approach
Why does a patient need to be sat at 30-45 degrees for pericardiocentesis?
To allow pericardial fluid to pool inferiorly.
Where should a needle be inserted for pericardiocentesis?
1cm below the left xipho-costal angle.
What angle should the needle be inserted at for pericardiocentesis and where should it be aimed?
Inserted at a 30 degree angle and aimed at the midpoint of the left clavicle.
Where are the aortic sinuses?
Small openings found within the aorta behind the left and right flaps of the aortic valve.
Which areas of the heart are supplied by the LAD?
RV
LV
Anterior 2/3rds IV septum
Which areas of the heart are supplied by the left marginal artery?
LV
Which areas of the heart are supplied by the left circumflex artery?
LA
LV
Which areas of the heart are supplied by the RCA?
RA
SAN
AVN
Posterior IV septum
Which areas of the heart are supplied by the right marginal artery?
RV
Apex
Which areas of the heart are supplied by the posterior inter ventricular artery?
RV
LV
Posterior 1/3rd of IVS
Which ECG leads correspond to the inferior region of the heart?
II, III, aVF
Which ECG leads correspond to the anterolateral region of the heart?
I, aVL, V5, V6
Which ECG leads correspond to the anteroseptal region of the heart?
V1, V2
Which ECG leads correspond to the anteroapical region of the heart?
V3, V4
Which ECG leads correspond to the extensive anterior region of the heart?
I, aVL, V2-V6
Which ECG leads correspond to the posterior region of the heart?
Tall R in V1
ECG changes in leads II, III and aVF suggest blockage in which artery?
RCA
ECG changes in leads I, aVL, V5 and V6 suggest blockage in which artery?
Left circumflex
ECG changes in leads V1, V2 suggest blockage in which artery?
LAD
ECG changes in leads V3, V4 suggest blockage in which artery?
Distal LAD
ECG changes in leads I, aVL and V2-V6 suggest blockage in which artery?
Proximal LCA
The LCA gives rise to which coronary arteries?
LAD
Lcx
Left marginal
The RCA gives rise to which coronary arteries?
Right marginal
What is the nerve supply to the fibrous pericardium?
Phrenic nerve
Which layer of the serous pericardium is supplied by the phrenic nerve?
Parietal layer