Goal 2: Pericardium Flashcards
Describe the location of the pericardium. What is behind it? What’s in front of it?
- front: sternum body, 2-6th coastal cartilages
- behind: T5-T8
What are the two types of pericardium?
- outer- fibrous
- inner- serous— parietal layer and visceral layer
What is the transverse sinus? What is the surgical significance of the transverse sinus?
- transverse passage between tubular reflections of serous pericardium, lined by visceral layer ONLY
- CABG- clamp arterial and venous ends during surgery
What sinus is found between parietal and visceral layers of pericardium? This sinus is closed at all sides except?
- oblique sinus
- except below
From what artery does the internal thoracic artery arise from?
Subclavian artery
List artery path starting from the subclavian artery. (Pericardium)
- subclavian
- internal thoracic
- pericardiocophrenic
- musculophrenic and internal thoracic arteries
What arteries are located in the visceral layer of pericardium?
Coronary arteries
If the brachiocephalic vein is ligated, what vein is at risk?
Pericardiacophrenic
From center of heart to the outside, what nerves are there?
-in to out: recurrent laryngeal, vagus, phrenic
Pain is felt at dermatones C3-C5 in relation to the heart. What nerve is possibly the cause? Where is dermatone C3-C5?
- phrenic nerve
- top of shoulder, ipsilateral supraclavicular region
Where do you hear pericardial friction rubs? What do you hear? What causes this?
- with stethoscope, over the left sternal border and upper ribs
- rustle of silk
- inflamed pericardium, causes chest pains
Patient has fluid in their pericardium. What is this called? Why is this bad?
- pericardial effusion
- can’t fully expand heart when it pumps
What is cardiac tamponade? Why is it life threatening? How is it treated?
- excess fluid in pericardial cavity
- compresses heart and doesn’t allow it to pump properly. Decreases heart’s CO and increase venous pressure
- pericardiocentesis
Where is the needle inserted to perform a pericardiacentesis?
-left subcostal angle, through the left 5th or 6th intercostal space by sternum
What part of the mediastinum is the pericardium located?
Middle mediastinum
The cardiac cycle starts with what and end with what?
- starts with diastole- filling
- ends with systole- emptying or contracting
What are the 3 layers of the heart CHAMBERS?
- endocardium: thin internal, connective tissue
- myocardium: thick, middle- cardiac muscle
- epicardium: thin external, visceral layer
What chamber of the heart does the apex mostly comprise of? Base?
- apex: left ventricle
- base: partly right and left ventricle
If a bullet went through the right parasternal border ABOVE the 3rd rib, what structure will get hit?
SVC
If a bullet went between the 3rd and 6th right ribs, what structure will get hit?
right atrium
If a bullet went through the left parasternal border between the 3rd and 5th ribs, what structure will get hit?
Right ventricle
If a bullet went through the left para stern Al border at the 2nd intercostal space, what structure will get hit?
Left atrium
What structure increases the right atrium’s capacity to hold more blood?
Right auricle
Where would you find the foramen ovale in a fetus?
At the interstitial septum
What structures comprise the right ventricle?
Traveculae carneae: irregular muscular elevations
What is the purpose of papillary muscles? What connects these muscles to the valves?
- prevent valve prolapse
- chordae tendinae
The superior part of this marks the SA node and it runs from IVC to SVC.
Crista terminalis
What is S1 and S2? Which comes first?
- S1: mitral and tricuspid closing
- S2: semilumar valves
- S1 first and then S2
Which heart valves have 3 cusps? Which have 2?
- 3: tricuspid, aortic, pulmonic
- 2: bicuspid
Describe the location of where to auscultate the septic valve, pulmonic, tricuspid, and bicuspid.
- aortic: upper right sternum border, 2nd ICS
- pulmonic: upper left eternal border 2nd ICS
- tricuspid: left 5th ICS at sternal Border
- bicuspid: left 5th ICS, near midclavicular line, at apex
What does the RCA supply? LCA?
- RCA: right atrium and ventricle, part of left ventricle and iv septum (posterior third), some SA and AV node
- LCA: left atrium and ventricle, most of the IV septum, AV bundle, some SA node
What are the two main branches from the LCA?
-LAD and circumflex arteries
What causes angina pectoris? What symptoms do you see? Explain why the pain sensation is the way it is.
- not enough blood flow to the myocardium
- left arm shoulder or neck pain, weakness, dizziness, short of breath
- heart pain expressed from sensory sympathetic cardiac nerve to T1-T5 but at the LEFT dorsal root ganglion, hence the left sided pain
What causes a complete heart block? When does necrosis start to set in?
- thrombus or embolus formation
- 20-30min after occlusion
What vessel is known as the “widow maker” and why?
- LAD
- supplies 2/3rds of the anterior IV septum (needed to move both ventricles)
What are the main 2 vessels used in CABGs? Why are these vessels used?
- great saphenous vein (leg)
- internal mammary artery (chest)
- a lot of elastic tissue and less chance of reocclusion
What vessels all drain into the coronary sinus?
- great cardiac vein
- middle cardiac vein
- small cardiac vein
- left posterior ventricular vein
- left marginal vein
- anterior cardiac veins
- venae cordis minimae/Thebesian veins
What are the parasympathetic and sympathetic innervations of the conduction system of the heart?
- Parasympathetic: Vagus and
- Sympathetic: T1-T5
Where is the SA node and what vessel supplies it? What’s another name for SA node? Where is the AV node and what vessel supplies it?
- SA: aka pacemaker of heart, find in upper part of crista terminalis (bottom of SVC), RCA supplies it
- AV: find between opening of coronary sinus and septal cusp of tricuspid valve, RCA supplies it too
What’s at the end of the Bundle of His?
Purkinjie fibers aka subendocardial plexus
What forms the superficial cardiac plexus? Deep cardiac plexus? Where do you find them?
- Superficial: left superior cervical sympathetic ganglion and lower cervical cardiac branch of left vagus nerve—find below arch of aorta and in front of right pulmonary artery
- deep: branches of both left and right cervical sympathetic ganglia (EXCEPT left superior), upper 4 or 5 thoracic sympathetic ganglia, both vagus—in front of bifurcation of the trachea
What are the sympathetic and parasympathetic of the heart?
- symp: preganglionic from T1-T4/T5, postganglionic at upper cervical/thoracic ganglia
- para: vagus
What is the ONLY route for impulse form the atria to ventricles? If this is broken, what happens? What’s the treatment?
- AV node
- if broken, slows heart rate without impulse
- need pacemaker to set heart rate needed to live
What congenital defect of the heart can cause you to not auscultate the heartbeat at the left side of thorax?
Dextrocardia
To start counting the ribs, where do you start from?
- At the sternal angle (where sternum body and manubrium meet)
- sternal angle= second rib
At what vertebrae level is the arch of aorta?
T4
For CABGs, what do they do to the great saphenous vein when used as a graft and why?
-they have to flip the vein the opposite way since it has valves!
What vein runs with right marginal branch of the right coronary artery?
Small cardiac vein
What artery runs with the great cardiac (anterior inter-ventricular) vein?
Anterior interventricular branch (LAD) of the left coronary artery
