The Heart Flashcards
What is diastole?
Begins with a period of ventricular elongation and filling
What is systole?
A period of ventricular shortening and emptying
How is the primary heart field developed?
Progenitor heart cells in epiblast (primitive ectoderm) of the third week embryo migrate though the primary streak and form the primary heart field (PHF) which forms the two Arita and most of the two ventricles in the lateral plate mesoderm
Day 15 and 18
Review heart embryology in notes.
Placeholder
What is the cardiogenic region?
The combined heart fields, primary heart field and secondary heart field
What does the secondary heart do?
Form the remainder of the hear and outflow tract not formed by PHF
Why does he right heart life anteriorly and the left heart posteriorly?
It’s a results of cardiac folding in the 4th week of intrauterine
What are the parts on the anterior or sternocostal surface?
Right atrium
Right ventricle
Atrio-ventricular groove
AVG
What is located on the posterior or base heart surface?
Mostly left atrium
What is located at the diaphragmatic surface of the heart?
Right and left ventricles and posterior interventricular groove (PIG)
What are the borders of the heart?
Superior: 3rd R CC to 2nd L CC
Inferior: right atrium and R ventricle from 6th cc parasternal to the site of apex bet at 5th L intercostal space MCL (5th LICS, MCL)
Right border: superior vena cava, right atrium, inferior vena cave from 3rd R CC to 6 R CC
Left: Left auricle and left ventricle from 2nd LCC to apex beat site (5th LIS, MCL)
Where is the apex beat or the site of maximum cardiac impulse?
5th intercostal space, mid-clavículas line (5th LICS, MCL)
Where is the AV node artery given off?
At the heart crux
What is the heart crux?
The point of intersection between inter-atrial (IAG), inter-ventricular (IVG) and atrio-ventricular grooves (AVG)
What is the atrioventricular node necessary for?
Excitation and contraction of the ventricles
Where is the atrium proper of the right atrium located?
Anteriorly next to the auricular appendage
-they are line by the pectinate muscle
What is the only part not derived from the venous part of the primitive heart tube (sinus venous) in the right atrium?
The posterior smooth willed sinus called the sinus venerum cavarum
Where is the sinoatrial node (SAN) located?
At the junction of SVC opening and superior end of crista terminalis
What are the crista terminalis?
Form the spine of the half comb and lies between the sinus venerum and pectinate muscle and between the opening of SVC and IVC
The opening of the coronary sinus lies between what 3 structures?
Fossa ovalis
IVC opening
Tricuspid valve opening
What is the fossa oval is?
A depression on the inter-atrial septum, where the foramen ovale used to be. It’s sharp margin is called limbus/annulus fossa ovalis
What is the tendon of todaro?
A part of the fibrous part of the heart, it runs from between the valves of IVC and Coronary sinus to the limbus foss oval is
What are the boundaries to the triangle of Koch?
Tendon of Todaro
Margin of orifice of coronary sinus
Septal leaflet of tricuspid valve
What lies in the middle of the triangle of Koch?
AVN
What chamber first received the freshly oxygenated blood from the lungs through the four pulmonary veins?
The left atrium
What forms the largest part of the sternocostal/anterior surface of the heart?
The right atrium
Where is the tricuspid valve?
Between the right atria and ventricle
What is the supraventricular crest?
A thick muscular ridge which links the inflow and outflow tracts of the right ventricle.
What does the supraventricular crest support or separate?
A. Anterosuperior leafleft or tricuspid valve
B. Septomarginal band (septomarginal trabeculae = moderator band)
Separates the attachments of tricuspid and pulmonary valves
What is the aortic vestibule?
The smooth outflow area of the left ventricle
How much thicker is the left ventricle than the right?
3x thicker
Does not have a moderator band
Where is the endocardium of the heart thicker?
On the heart
What is the valve location, anatomical location and auscultation site?
Valve: PAMT
Loc: 3rdCC,3rdICS,4th CC,4thICD
Site: 2nd Lt ICS, 2nd Rt ICS, cardiac apex (5th Lt ICS MCL), Rt inferiormost ST (? 5th Rt ICS)
When do peripheral arteries fill and when do coronary arteries fill?
P: during systole
C: during diastole due to elastic recoil of the aorta
What are cardiac veins missing?
Valves
What kind of ANS innervation do the coronary arteries receive?
Para and sympathetic
What are the branches of the right coronary artery?
(VICAN) Ventricular Interventricular septum (perforator) Conus Atrial Nodal
What is the distribution of the right coronary artery?
Rt atrium
Rt and left ventricles on the diaphragmatic surface
Poster 1/3 of IVS
Both nodal tissues
What potential anastomoses does the right coronary artery have?
Circumflex
LADA
Perforator
What are the branches for the Left coronary artery?
(VICAN) Ventricular Interventricular septum (perforator) Conus Atrial Nodal
Wat is the distribution of the left coronary artery?
LT atrium Lt ventricle (most) Rt ventricle (some) Anterior 2/3 of IVS including bundle of His Nodal
What are the potential anastomoses for left coronary artery?
RCA
PIVA
Perforators
How is the coronary dominance decided?
By which of the 2 coronary arteries gives off the posterior interventricular artery (PIVA)
Coronary dominance is most likely in which artery?
The right 65%
What is the artery of sudden death?
LAD
What is the collecting vein or sump of the heart?
Coronary sinus
What forms the coronary sinus?
A merger of the great cardiac vein and oblique vein of Marshall ( of left atrium)
What veins drain into the coronary sinus and what arteries accompany them?
A. Great cardiac vein (LADA) B. Middle cardiac vein (PIVA) C. Small cardiac vein (right marginal artery) D. Lt posterior ventricular vein E. Oblique vein of Marshall
What veins do not drain into coronary sinus?
Anterior cardiac veins and Vanar cordis minimae
What do the lymphatic of the heart drain?
The cardiac lymphatic plexus located in the subepicardial fat
Where do the lymphatics of the heart drain into?
Tracheo-bronchial lymph nodes
Where does the heart receive sympathetic innervation from?
All 3 cervical ganglia which are from T1-t4/5 thoracic ganglia and they form the cardiac plexus
To coronary arteries and nodes
SAN and AVN (SAN –Sympathetic to Atria and Nodes)
Where does the heart receive parasympathetic innervation from?
From 2 vagus nerves and 2 RLNs
To coronary arteries and atrial wall
(APA- Parasympathetic to Atria and Arteries)
Trace the electrical conduction of the heart
SAN AVN Atrio-ventricular bundle of his (AVB) Atrio-ventricular bundle branches (AVBBs) Purkinje fibers
What is the pacemaker of the heart?
Sino-atrial node (SAN)
-has intrinsic rhythmicity and automaticity that generates a wave of depolarization which spread in the atria
Where is the SAN located?>
Between the superior end of crista terminalis and inferior end of SVC, in the anterior wall of right atrium
What is that only tissue through which electrical impulses pass from atria to ventricle?
Atrio-ventricular node (AVN)
Where is the AVN located?
Between the posteroinferior end of inter-atrial septum and septal leaflet of tricuspid valve (also within the triangle of Koch)
Where is AVB located?
In the membranous part of the interventricular septum
What carries impulse to cardiac apex via right and left bundle branches in the inter-ventricular septum?
AVB
What takes impulses to the moderator band?
AV Bundle branches
What are the purkinje fibers of the heart?
Terminal conducting fibers which are located in all parts of the ventricular wall.
List the order of systole (S)?
S1
- A-V valves shut, with semilunar valves already shut (all 4 valves shut)
- Isovolumetric ventricular contraction
S2
- Semilunar valves open,
- Ejection period
List the order of Distole (D)
D1.
1. Semilunar valves closes, while A-V valves are closed
2. Isovolumetric relaxion
D2
1.A-V valves open, while semilunar valves are still closed
2. Passive ventricular filling
D3
1. Semilunar valves still closed A-V valves are open
2. Active ventricular filling as the atria make a last ditch contraction
Is there ever a time when all four valves are open?
NO, never dude.
What shows various events of the cardiac cycle, pressure changes, phonocardiogram and electrocardiogram?
Wiggers diagram
What relationship does wiggers diagram show?
Fill in later?
Why is cardiac pain referred?
They are innervated by splanchnic nerves,
Splanchnic nerves do not receive their own pathway and hitchhike on somatic pathways