Anatomy and Physiology Flashcards
The heart appears to be a what shape?
Cone / inverted triangle shaped
The heart relatively same size as what?
Closed fist
Where does the heart rest?
Diaphragm
Where is the hear located?
Mediastinum
What is the inferior border of the heart?
Diaphragm
What is the lateral border of the heart?
Lungs
What is the anterior border of the heart?
Sternum
What is the posterior border of the heart?
Vertebra
What structure forms the anterior surface of the heart?
RIght Ventricle
___ forms the most posterior heart surface
Light Atrium
___ forms heart’s apex
Left Ventricle
What are the anterior surfaces of the heart? (2)
Right Atrium and Ventricle
What is the posterior surface of the heart? (2)
Right and Left Atrium
What are the inferior surface of the heart? (2)
Right and Left Ventricle
What are the layers of the heart?
- Pericardium
- Epicardium
- Myocardium
- Endocardium
Fibrous connective tissue that encloses the heart
Pericardium
What is the function of the Pericardium?
Protects heart from trauma and infection
The outermost layers of the pericardium is called a ___?
Fibrous Pericardium
What is the function of the Fibrous Pericardium?
It anchors hearts on mediastinum and it prevents the heart from over stretching
The innermost layer of the pericardium is called a ___?
Serous Pericardium
A layer that adheres tightly to the fibrous pericardium
Parietal Serous Pericardium
What is the outermost layer of the Serous Pericardium?
Parietal Serous Pericardium
Layer that adheres tightly to the heart
Visceral Serous Pericardium
Normal value of Pericardial Fluid
15 mL
What is the function of the Pericardial Fluid?
decrease friction in heart to prevent friction rub
Where is the pericardial fluid located?
between the visceral and parietal SP (pericardial space)
Increase pericardial fluid results to:
Cardiac Tamponade
(-) pain
Death 2* to MI d/t unable to pump blood
Decrease pericardial fluid results to:
Pericardial Friction Rub
Pain
Pericarditis
What are the 2 parts of the atrioventricular valve?
Tricuspid and bicuspid (Mitral) Valve
What are the 3 parts of the semilunar valve?
Pulmonary, Aortic, Outlet
Also called the receiving chamber
Atria
Muscle present in the anterior wall of the 2 atria making the texture rough
Pectinate Muscle
Opening of the interatrial septum of a fetal heart
Foramen Ovale
Remnant of foramen ovale
Fossa Ovalis
Oval depression
Fossa Ovalis
Also called the pumping chambers
Ventricles
What is the fiber called in the ridges of the cardiac muscle?
Trabeculae Carbae
Cone shape structure of trabeculae carnae where the chordae tendinae are attached
Papillary muscle
Structure that separates 2 ventricles
Interventricular Septum
Provides blood supply to the heart
Coronary Artery
Supplies blood in the Anterior Wall and Apical Wall of the (L) Ventricle
Left Anterior Descending Artery (LADA)
Supplies blood to the Lateral Wall and Inferior Wall of (L) Ventricle
Circumflex Artery
Most common L sided heart failure
Left ventricular failure
Direct covering of the heart
Epicardium
contractile unit of the heart
Mayocardium
Smooth lining of the heart
Endocardium
What happens in S3?
Rapid filling of ventricles
In CHF: Ventricular Gallop by non-contractile left ventricle CHF (dec contraction)
What part of pregnancy is ventricular gallop expected?
Last trimester
What happens in S4?
Atrial Systole
In MI/HTN: Atrial gallop
What causes S4 sound?
MI, CAD, Stenosis, HTN (overwork), Athlete
Direct connection of SA et AV node
Internodal Pathway
Drugs used for decreased contraction
beta-blockers
calcium channel blocker
alpha-1 locker
ANS effect in the heart
para- decrease contraction
sympa- increase contraction
Aka Sinus Node
Sinoatrial Node (SA Node)
Primary pacemaker
SA Node
SA Node rate (bpm)
60-100 bpm
What is the general location of SA node?
R Atrium
What is the specific location of the SA Node?
Superior Septum Wall of th eRA bet slightly lateral to the opening of the Superior Vena Cava
Aka Junctional Node
Atrioventricular Node
Secondary Pacemaker
AV node
AV node rate (bpm)
40-60 bpm
Where is the AV node located?
Behind the tricuspid valve
mc site for H.B.
AV Node
Location of Bundle of His
Interventricular Spetum
Where is the Purkinje Fibers located?
Surrounds the 2 ventricles
Largest pacemaker of the heart
Purkinje Fibers
Tertiary pacemaker
Purkinje fibers
Tertiary pacemaker rate (bmp)
20-60 bpm
What is the resting membrane potential of the cardiac action potential?
-88mV
What happens during Phase 0 of cardiac action potential?
Depolarization
inward current of Na+
What happens during phase 1 of cardiac action potential?
Initial repolarization
decrease of Na+
Outward current of K+
What happens during phase 2 of cardiac action potential?
Plateau “pla-two”
Inward current of Ca2+
What happens during phase 3 of cardiac action potential?
Repolarization
Decrease influx of Ca2+
Outward current of K+
What happens during phase 4 of cardiac action potential?
Resting membrane potential
return to -88mV
What happens during diastole?
ventricular Relaxation
What happens during systole?
Ventricular Contraction
What happens during isovolumetric contraction?
no change in volume
What happens during ventricular ejection?
increase systolic pressure
What happens during isovolumetric relaxation
ventricles return to the start point
What happens during ventricular filling?
passive filling