Anatomy - Coronary Arteries and Heart Chambers Flashcards
What is the pericardium?
Fibroserous sac surrounding the heart and roots of great vessels
2 components of pericardium? Describe each.
- Serous pericardium: thin with 2 parts2. Fibrous pericardium: tough connective tissue defining the borders of the middle mediastinum
2 portions of serous pericardium? Describe each.
- Parietal layer lining the inner surface of the fibrous pericardium2. Visceral layer adhering to the heart
Other name for visceral pericardium?
Epicardium
Where are the visceral and parietal pericardial layers continuous?
At the roots of the great vessels
Describe the borders/attachments of the fibrous pericardium.
- Inferiorly: base attached to the central tendon of the diaphragm and to a small muscular area on the left side 2. Superiorly: apex continuous with tunica adventitia of great vessels 3. Anteriorly: attached to posterior surface of sternum by sternopericardial ligaments
Purpose of fibrous pericardium?
- Retains heart in its position2. Limits cardiac distention
Innervation of fibrous pericardium? Location of these nerves related to what?
Phrenic nerves Related to embryological origin of the diaphragm and changes that occur during the formation of the pericardial cavity
Blood supply of fibrous pericardium? Location?
Pericardiacophrenic arteries located within the fibrous pericardium
What are the 2 pericardial sinuses?
Reflections of serous pericardium:1. Oblique pericardial sinus2. Transverse pericardial sinus
Describe the oblique pericardial sinus.
Cul-de-sac posterior to the left atrium formed by the posterior reflection surrounding the pulmonary veins, SVC, and IVC that is J shaped
Describe the transverse pericardial sinus.
Passage posterior to the ascending aorta and pulmonary trunk anterior to SVC and superior to LA, between the reflection surrounding the pulmonary veins and a superior reflection surrounding the arteries, the aorta, and the pulmonary trunk
During surgery, how to separate the veins from the arteries in the great vessels?
Open pericardium anteriorly and place a finger in the transverse sinus
During surgery, how to place hand in the oblique pericardial sinus?
Place hand under apex of the heart and move it superiorly and posteriorly to slip into it
5 arteries supplying the pericardium?
Branches from:1. Pericardiacophrenic arteries2. Internal thoracic arteries 3. Musculophrenic arteries4. Inferior phrenic arteries5. Thoracic aorta
Where do veins from the pericardium drain?
- Azygos system of veins2. Internal thoracic veins3. Superior phrenic veins
3 nerves innervating the pericardium?
Arise from:1. Vagus nerves2. Phrenic nerves3. Sympathetic trunks
Where is pain from parietal and fibrous pericardia felt?
Pain in C3-C5 dermatomes = lateral neck and supraclavicular region of shoulder
What is pericarditis? Common causes?
Inflammatory condition of the pericardium Common causes: viral, bacterial infections, systemic illnesses (chronic renal failure), and after myocardial infarction
What is a common cause of bacterial pericarditis? How can this be avoided?
Oral surgeryProphylactic antibiotics
How to distinguish pericarditis from myocardial infarction in a patient?
Pain in both in central chest that radiates to one or both arms Pain of pericarditis may be relieved by sitting forward and a EKG is used to distinguish them for sure
What is pericardial effusion? Treatment?
Pericardial cavity becomes a real space with fluid build-up causing compression of the heart = cardiac tamponade and biventricular failure Treatment = pericardiocentesis (draining)
Where exactly is pericardiocentesis performed? Why? Other name for this area?
Bare area of the pericardium = Larrey’s area => just inferior to the 5th rib (5th intercostal space) about 1 inch to the left of the sternumNo lung overlying this area
What is constrictive pericarditis? Diagnosis? Treatment?
Abnormal thickening of the pericardial sac that can compress the heart and result in heart failureDiagnosis: inspect jugular venous pulse for Kussmaul’s signTreatment: surgical opening of pericardium
What is jugular venous distention called? When is this observed?
Kussmaul’s sign During inspiration, when the venous pressure in the jugulars is supposed to decline
Borders of mediastinum?
- Laterally: pleural cavities2. Anteriorly: sternum3. Posteriorly: thoracic vertebrae4. Superiorly: thoracic aperture5. Inferiorly: diaphragm
Parts of mediastinum?
- Superior2. Inferior: anterior, middle, and posterior
Describe the pericardium in cadavers.
Fibrous and parietal pericardia are adhered together and cannot be separated
How is one of the cardiac sinuses exploited during bypass surgery?
The location of the transverse one is exploited as a surgical clamp is introduced into the space to separate the aorta from the pulmonary trunk and then blood flow of the aorta/pulmonary trunk is stopped momentarily before great vessels are connected to the bypass machine
Describe the orientation of the heart.
Pyramid resting on its side with apex pointing forward, downward, and to the left and base facing posteriorly
Components of the base of the heart?
- LA2. Small portion of RA3. Proximal parts of great veins: pulmonary veins and venae cavae
What is unique about the LA compared to the other heart chambers?
- It does not sit on the diaphragm (large gap between the 2)2. It rests directly on the esophagus posteriorly (soft vertical bump on LA if you remove the heart) - both are perpendicular to each other
Vertebral borders of base of the heart?
Sitting: T5 to T8Standing: T6 to T9
What is the apex of the heart formed by? Surface projection?
Formed by inferolateral part of the LVSurface projection: left 5th intercostal space, 8-9 (3.3 inches) cm from the midsternal line
How many surfaces does the heart have? Describe them.
- Anterior surface: mostly RV with a little RA and LV 2. Diaphragmatic surface: LV and small portion of RV 3. Left pulmonary surface: faces the left lung, is broad and convex and is mostly LV and portion of LA4. Right pulmonary surface: faces the right lung is broad and convex and is the RA5. Base surface: mostly LA
What separates the diaphragmatic surface of the heart and the base of the heart?
Coronary sinus
How many margins does the heart have? Describe them.
4 total: 1. Inferior margin: sharp edge between diaphragmatic and anterior surfaces (mostly RV + LV near apex)2. Right and left margins = right and left pulmonary surfaces3. Obtuse margin: round edge between left pulmonary surface and diaphragmatic surface extending from left auricle to cardiac apex (mostly LV + left auricle superiorly)
Other name for inferior margin of the heart?
Acute margin of the heart
Other name for anterior surface of the heart?
Sternocostal
What forms the external coronary sulci?
Internal partitions dividing the heart into 4 chambers
What are the 2 sulci of the surface of the heart? Describe the position of each.
- Coronary sulcus: between the atria and the ventricles circumscribing the entire heart2. Anterior and posterior interventricular sulci: between the ventricles on both the anterior and posterior surfaces of the heart
3 vessels in coronary sinus?
- RCA2. Small cardiac vein3. Circumflex branch of LCA
Where is the coronary sinus located exteriorly?
Runs along the posterior coronary sulcus, medial to the IVC
Where do all of the cardiac veins drain?
All in the coronary sinus of the RA, except for the anterior cardiac veins which drain directly into the RA
2 vessels in anterior interventricular sulcus?
- Anterior interventricular artery2. Great cardiac vein
2 vessels in postterior interventricular sulcus?
- Posterior interventricular artery2. Middle cardiac vein
Position of visceral pericardium in regards to coronary sulci and vessels?
Superficial to
Where do the coronary arteries arise from?
From the aortic sinuses in the initial portion of the ascending aorta
2 coronary arteries?
Right and left
Describe the course of the RCA.
Right aortic sinus => passes anteriorly and then descends vertically in the coronary sulcus between RA and RV => inferior margin of heart => turns posteriorly onto diaphragmatic surface and base of heart
4 branches of RCA and their location?
- Atrial branch between right auricle and ascending aorta 2. Sinu-atrial nodal branch (off of atrial branch) which passes posteriorly around SVC to supply SA node 3. Right marginal branch off of the inferior margin of the RCA along border toward apex 4. Posterior interventricular branch
Which coronary artery supplies the AV node?
Small branch of RCA on base/diaphragmatic surface of the heart
List all of the structures supplied by the RCA.
- RA2. RV3. SA node4. AV node5. Interatrial septum6. Portion of LA7. Posteroinferior third of the IV septum 8. Portion of posterior part of LV
Describe the course of the LCA.
Left aortic sinus of ascending aorta => posterior to pulmonary trunk and anterior to left auricle => barely in coronary sulcus
3 branches of LCA? Include locations
- Anterior interventricular branch descends obliquely toward apex of the heart in the anterior IV sulcus (with 1-2 diagonal branches)2. Circumflex branch in coronary sulcus onto base/diaphragmatic surface ending before reaching the PIB 3. Left marginal artery from the circumflex branch continues across the obtuse margin
Other name for anterior interventricular branch of LCA?
Left anterior descending artery = LAD
List all of the structures supplied by the LCA.
- Most of LA2. Most of LV3. Most of IV septum (including AV bundle and bundle branches)
What does heart dominance refer to?
Refers to which side of the heart is responsible for giving rise to the posterior interventricular arteryMost people (85%) are right heart dominant For 15% of people the PIB branches off the circumflex branch of the LCA
What does the PIB supply?
Large portion of posterior wall of LV + posterior wall of RV + inferoposterior 1/3rd of IV septum
When not supplied by RCA, what supplies the SA and AV nodes?
Circumflex branch of LCA
Other name for PIB?
Posterior descending artery (PDA)
Other name for short LCA?
Left main stem vessel
What are the 5 major branches of the coronary veins? What about the minor 5th one? Describe their location and size.
- Great cardiac vein: LARGE, starts at apex => anterior IV sulcus => follows circumflex branch => enlarges to form LONG LARGE coronary sinus2. Middle cardiac vein: MEDIUM, starts at apex => posterior IV sulcus 3. Small cardiac vein: SMALL, starts at lower anterior portion of coronary sulcus between RA and RV => base/diaphragmatic surface 4. Anterior cardiac veins: SMALL, on anterior border of RA and RV running along RV anterior surface and entering the anterior wall of the RA 5. Posterior cardiac vein: SMALL, posterior surface of LV to the left of the middle cardiac vein6. Marginal vein: usually branches from the small cardiac vein running with the marginal artery of the RCA or just part of the anterior cardiac veins
Which are more superficial: coronary arteries or veins?
Veins
Where do all of the cardiac veins drain?
All in the coronary sinus of the RA, except for the anterior cardiac veins (and sometimes the posterior cardiac vein) which drain directly into the RA
Where are marginal branches of the coronary arteries located?
Run towards the apex of the heart
How are the coronary arteries accessed in an angiogram?
Catheter is inserted into the femoral artery and passed in a retrograde manner through the aorta into the coronary arteries (VERY invasive)
What area will be oxygen deprived by a blood clot or plaque that occludes a vessel?
The area DISTAL to the blood clot
What are the 6 sites of coronary occlusion in order of frequency?
- Anterior interventricular branch of the left coronary artery (or LAD) (40-50%)2. Right coronary artery (30-40%)3. Circumflex branch of the left coronary artery (15-20%)4. Left coronary artery5. Posterior interventricular branch of the right coronary artery6. Marginal artery branch of the right coronary artery
Other name for middle cardiac vein?
Posterior IV vein
What arteries is the great cardiac vein associated with?
LAD and circumflex
What arteries is the middle cardiac vein associated with?
PIB
What arteries is the small cardiac vein associated with?
RCA and its marginal branch
What arteries is the posterior cardiac vein associated with?
None
What are the venae cordis minimae? Other name?
Smallest cardiac veins draining directly into cardiac chambers (numerous on right and few on left, especially LV) through the foramina of the venae cordis minimae Also called veins of Thebesius
Lymphatic drainage of heart?
Follows coronary arteries and drains into:1. Brachiocephalic nodes2. Tracheobrachial nodes
RA receives blood from what 4 vessels? Where does each enter?
- SVC: posterior superior surface2. IVC: posterior inferior surface3. Coronary sinus: posterior inferior surface4. Anterior cardiac veins: anterior surface
Through what does blood pass to go from RA to RV? In what direction does blood flow?
Right atrioventricular orifice with tricuspid valve Direction of blood: horizontal and forward
What are the 6 components of the inside of the RA?
- Pectinate muscles2. Fossa ovalis3. Crista terminalis4. Vessels that drain into the RA5. SA node6. AV node
What is the crista terminalis?
Longitudinal smooth raised ridge running from anterior opening of SVC to anterior opening of IVC on the lateral border of the RA and separates the anterior and posterior walls
What is the sulcus terminalis cordis?
Shallow vertical groove on external surface of the RA from right of SVC opening to right of IVC opening
What is the sinus of the venae cavae derived embryologically from?
Right horn of sinus venosus
What is the sinus of the venae cavae?
Space posterior to the crista in the RA with smooth thin walls where both venae cavae empty
What is the atrium proper?
Space anterior to crista including the auricle in the RA
What is the atrium proper derived embryologically from?
Primitive atrium
Where are the pectinate muscles located in the RA? Function?
Horizontal rough inner surface of the atrium proper Allow for atrial contraction
What is the right auricle?
Ear-like conical muscular pouch externally overlapping the ascending aorta
Location of coronary sinus in relation to IVC?
Medial
What structure helps incoming blood through foramen ovale during development?
Valve of IVC
What are the small folds of tissue around the openings of the IVC and coronary sinus? Embryological derivation?
They are the valve of the IVC and coronary sinus from the valve of the sinus venosus
Direction of interatrial septum?
Forward and to the right
What is the thinnest portion of the interatrial septum
Valve of foramen ovale (opposite floor of fossa ovalis is RA)
What is the prominent margin of the fossa ovalis called?
Limbus fossa ovalis
What are the 5 components of the RV?
- Tricuspid valve 2. 3 papillary muscles with chorda tendinae3. Septomarginal trabecula 4. Trabeculae carneae5. Conus arteriosus
What are the different cusps of the tricuspid valve?
- Anterior2. Posterior3. Septal
By what are the 3 cusps of the tricuspid valve connected to the papillary muscles?
Via cordae tendinae
What is another name for the septomarginal trabecula?
Moderator band
Function of septomarginal trabecula?
Connects the inferior portion of the interventricular septum to the base of the anterior papillary muscle in the RV
What does the septomarginal trabecula contain? Function?
The right bundle of the conducting system of the heart => carries signals for muscle contraction to the papillary muscles
What are the trabeculae carneae? Function?
Muscular ridges roughening the inner surfaces of the RV wall forming ridges and bridges to help support the walls of the ventricles
How do the papillary muscles work?
Contract to prevent cusps from prolapsing back into the RA during ventricular contraction => aka they hold the cusps shut (but do not actively close them) to prevent them from leaking when the heart contracts
What is the conus arteriosus? What is it derived from embryologically?
Smooth walled outflow tract of RV leading to pulmonary trunk Derived from bulbus cordis
Other name for conus arteriosus?
Infundibulum
Are papillary muscles trabeculae carneae?
YUP
What are the 3 papillary muscles of the RV? Which is the largest? Which is most inconsistent?
- ***Anterior2. Posterior3. #Septal
How are the chordae tendineae attached to the ventricular wall?
3 trabeculeae carneae
What are the commissures of the tricuspid and bicuspid valves?
Sites where the bases of the cusps of the valves are continuous
What would necrosis of a papillary muscle following a myocardial infarction lead to?
Valve prolapse
Describe the cusps of the pulmonary and aortic valves.
3 semilunar cusps with free edges projecting into pulmonary trunk/aorta with 2 parts:1. Nodule: middle, thickened2. Lunula: lateral, thin
What are the different cusps of the pulmonary valve?
- Left2. Right3. Anterior
How do the pulmonary and aortic valves close?
Each of their cusps has a pocket like sinus (dilation in wall of proximal pulmonary trunk/aorta) that fills with blood and forces the cusps closedAND in the aortic valve the blood recoiling also enters the coronary arteries
What veins drain into the LA?
4 pulmonary veins
Describe the 2 halves of the LA and their embryological derivation.
- Posterior half with smooth walls derived from the proximal portions of the pulmonary veins 2. Anterior half continuous with the left auricle and containing pectinati muscles derived from primitive atrium
Does the LA have crista terminalis?
NOPE
Is the interatrial septum part of the RA or LA wall?
LA (anterior wall)
What plane do ALL the heart valves lie on?
Plane of coronary sulcus
Are the heart valves heard at the skin level where they are located?
NOPE, downstream from the blood flow
Where to listen to aortic valve?
Right side of sternum below rib 2
Where to listen to tricuspid valve?
Left side of sternum below rib 5
Where to listen to mitral valve?
Apex beat of the heart: 5th intercostal space at the midclavicular line
Where to listen to pulmonary valve?
Left side of sternum below rib 2
Other name for R and L bundle branches?
Crura
Which AV valve is stronger: tricuspid or mitral? Why? Implication?
Mitral because it only has 2 cusps and needs to withstand so much more pressure Increase in pressure from LA to LV is 10x higher
Difference between papillary muscles in RV and LV? Explain why.
Not as prominent in LV because the left ventricle wall is thicker, so the papillary muscles are located closer to the mitral valve
What is the anterior chamber of the heart?
RV
What is the posterior chamber of the heart?
LA
Which heart chamber is most often contused in car accidents?
RV
Through what does blood pass to go from LA to LV? In what direction does blood flow?
Left atrioventricular orifice with mitral valve Direction of blood: forward to apex
Which ventricle is longer: RV or LV?
LV
What is the aortic vestibule? What is it derived from embryologically?
Smooth walled outflow tract of LV leading to aortaDerived from bulbus cordis
Position of aortic vestibule compared to infundibulum of RV?
Left and posterior
What are the 4 components of the LV?
- Mitral valve 2. 2 papillary muscles with chorda tendinae3. Trabeculae carneae4. Aortic vestibule
Compare the right and left trabeculae carneae?
Left ones are more fine and delicate
What are the 2 papillary muscles of the LV?
- Anterior2. Posterior
Is the IV septum part of the RV or LV wall?
LV
Parts of IV septum? Describe each.
- Muscular: thick and major part of septum2. Membranous: thin and upper portion*3. Atrioventricular portion between LV and RA
Location of mitral valve in LV?
Posterior superior
Cusps of the mitral valve?
- Anterior2. Posterior
What are the different cusps of the aortic valve?
- Right2. Left3. Posterior
Other name for posterior aortic sinus?
Noncoronary sinus
Heart surfaces of LA?
Most of the base + left pulmonary surface
Heart surfaces of RV?
Most of anterior surface + diaphragmatic surface
Heart surfaces of LV?
Most of left pulmonary surface + anterior surface + diaphragmatic surface
Heart surfaces of RA?
Most of right pulmonary surface + anterior surface
2 types of valve disease?
- Insufficiency2. Stenosis
What is mitral valve disease?
Mix of stenosis and insufficiency, with one of the 2 dominating
Changes in heart anatomy caused by mitral valve disease?
- LV hypertrophy2. Increased pulmonary venous pressure3. Pulmonary edema4. LA enlargement and hypertrophy
What is the cardiac skeleton?
Collection of dense fibrous connective tissue in the form of 4 rings (anulus fibrosus) with interconnecting areas in a plane between the atria and the ventricles surrounding:1. 2 atrioventricular orifices2. Aortic orifice3. Opening of pulmonary trunk
What are the 2 interconnecting areas of the anulus fibrosus?
- Right fibrous trigone between aortic ring and right atrioventricular ring2. Left fibrous trigone between aortic ring and left atrioventricular ring
What separates the atrial musculature from the ventricular musculature and isolates them electrically?
Cardiac skeleton
4 basic components of cardiac conduction system?
- SA node2. AV node3. AV bundle + R/L bundle branches4. Subendocardial Purkinje fibers
Describe the pathway of the heart conduction system.
Impulse signaling begins at SA node => impulses spread in a wave along cardiac muscle fibers of atria, signaling atria to contract => some impulses travel along the internodal pathway => AV node => impulse delay for fraction of a second => impulses pass through the AV bundle => impulses divide into R and L bundle branches => halfway through septum they become the subendocardial branches of Purjinke fibers => subendocardial branches approach heart apex and papillary muscles and arc superiorly to ventricular walls => ventricular myocardial contraction begins at apex in endocardium and then epicardium
Where is the SA node located?
Superior end of crista terminalis of RA at the junction with the SVC
Where is the AV node located?
Within atrioventricular septum, close to the attachment of the septal cusp of the tricuspid valve, near the opening of the coronary sinus
Where is the AV bundle located?
From AV node to lower border of membranous IV septum
Where is the right bundle branch located?
Right side of IV septum => septomarginal trabecula to base of anterior papillary muscle => divides and is continuous with Purkinje fibers
Where is the left bundle branch located?
Left side of IV septum => divides and is continuous with Purkinje fibers
Innervation of the heart?
Cardiac plexus with branches from sympa trunks and vagus nerves + visceral afferents
2 parts of the cardiac plexus? Location for each? Innervation of each?
- Superficial: inferior to aortic arch between it and pulmonary trunk 2. Deep: between aortic arch and tracheal bifurcation
What does the cardiac plexus innervate?
- Conduction system2. Coronary blood vessels3. Atrial and ventricular musculatures
Parasympathetic nerves to the cardiac plexus? Where do they synapse?
Preganglionic branches of the vagus nerves and recurrent laryngeal nerves synapse on postganglionic nerves in plexus or atrial walls
Sympathetic nerves to the cardiac plexus? Where do they synapse?
Preganglionic fibers from T1-T4/T5 => cervical sympathetic trunks => synapse in cervical ganglia and upper thoracic ganglia => postganglionic fibers to cardiac plexus
Pathway of visceral afferents from the heart? Which ones carry pain sensation?
Along both parasympathetic and sympathetic nerves from the cardiac plexus Those associated with sympathetic system conduct pain sensation
Do the SA and AV node appear differently in a cadaver?
NOPE
What is found between the heart and the parietal pericardium?
FAT
Are the 2 pericardial sinuses continuous?
NOPE
What connects the aorta and pulmonary trunk?
Ligamentum arteriosum
Where is the musculi pectinati mostly found in the LA?
Left auricle
Surface anatomy of upper limit of heart?
- 3rd costal cartilage on the right of sternum- 2nd ICS on left of sternum
Surface anatomy of right margin of heart?
Right 3rd costal cartilage to 6th costal cartilage
Surface anatomy of left margin of heart?
2nd ICS to apex at midclavicular line in 5th ICS (just inferior to the nipple in men)
Surface anatomy of lower margin of heart?
6th ICS to right of sternum to apex at midclavicular line in 5th ICS
Are the pulmonary trunk and ascending aorta contained in the pericardial sac?
YUP both covered by serous pericardium
Surface projection of ascending aorta?
Posterior to left half of body of sternum at the level of the lower edge of 3rd LEFT costal cartilage to the level of the lower edge of 2nd RIGHT costal cartilage
Surface projections of inferior half of SVC?
- Enters fibrous pericardium at right 2nd costal cartilage2. Enters RA at right 3rd costal cartilage
Surface projection of superior half of IVC?
Enters fibrous pericardium at T8
What kind of pericardium covers the SVC and IVC?
Serous
Why does the referred pain of the heart extends to the medial arm? Describe the process during myocardial infarction.
Cardiac cells die => pain is transmitted through visceral sensory afferent fibers enter the spinal cord between T1 and T4 where somatic afferents from spinal nerves T1 and T4 enter as well (including the brachial nerve) => both types of afferents synapse with second neurons => interneurons synapse with second neurons => second neuron fibers pass across the cord and ascend to the somatosensory areas of the brain that represent the T1-T4 levels => brain unable to distinguish between signals => pain interpreted as arising from somatic regions
What is referred pain? What is it due to?
Visceral pain perceived as originating from the skin or outer body (as somatic pain)May be due to reflexive vasoconstriction in the vessels supplying the corresponding somatic segments
Surface projection of mitral valve?
Upper border of LEFT 4th costal cartilage
Surface projection of tricuspid valve?
Middle of sternal body more to the right between ribs 4 and 5
Surface projection of aortic valve?
Behind left part of sternum at level of rib 4
Surface projection of pulmonary valve?
LEFT 3rd costal cartilage (lower)
Surface projection of RV?
Mainly posterior to the sternum
Can you see the left coronary artery from the anterior view of the heart?
NOPE, need left lateral view
Huge hole seen on posterior surface of the RA?
IVC
From the superior view of the heart, are all cusps of all valves visible?
Yes, except for those of the tricuspid valve
What is the longitudinal ridge lateral to the coronary sinus?
Valve of coronary sinus
If you are looking at a cross-section of the heart, what would be the bloody circular structure posterior to both ventricles in between them?
LA
What structure most rapidly conducts impulses to the anterior papillary muscles?
Moderator band
What structure transmits pain from angina pectoris?
Pain from angina pectoris results from ischemia of the myocardium and is transmitted primarily via afferent nerves that travel with sympathetic fibers so the upper sympathetic trunk is likely to have these fibers
How does pulmonary edema causes by LV failure affect gas exchange?
Restricts it
How long is the LCA?
2 cm
What is a common disorder caused by occlusion of the RCA? Explain.
Disorders of cardiac rhythm because the SA node and the AV node get their blood supply predominantly from the RCA
In what EKG leads would an occlusion of the RCA be noticed? Why? What is this called?
Leads II, III, and AVF because these visualize the inferior aspect of the myocardium, which the RCA predominantly supplied = inferior or anterior myocardial infarction
How to diagnose myocardial infarction with a blood test? Can this be done at an early stage of MI?
To detect enzymes released by the heart during MI = lactate dehydrogenase (LDH), creatine kinase (CK), aspartate transaminase (AST), and isozymes (creatine kinase MB) + troponin YES, it can!
How is nuclear medicine used to determine areas of coronary ischemia?
Thallium and its derivatives are potassium analogs and will be taken up by ALIVE myocardial cells only