Heart and Thorax Innervation Flashcards
transport blood away from the heart
arteries
transport blood toward the heart
veins
connect the arteries and veins & are where oxygen, nutrients, and wastes are exchanged within the tissues
capillaries
sternopericardial ligaments
attach the pericardium to the posterior surface of the sternum
pericardiacophrenic ligaments
attach the pericardium to the central tendon of the diaphragm
what attachments help to retain the heart in its position in the thoracic cavity?
sternopericardial and pericardiacophrenic ligaments?
what are the functions of the fibrous pericardium?
-protection
-stabilizes and limits cardiac distension
-prevents heart from overdilating and over filling with blood
potential space between the layers of serous pericardium
pericardial cavity
at what point does the pulmonary trunk divide into the right and left pulmonary arteries
at the level of the intervertebral disc between thoracic vertebrae 5 and 6
which division of the aorta lies in the superior mediastinum?
the arch of the aorta
what do the right and left pulmonary arteries carry?
originate from the pulmonary trunk and carry deoxygenated blood to the lungs from the right ventricle
how many pulmonary veins are their and what do they carry?
4 total- 2 on each side
-they carry oxygenated blood from the lungs back to the left atrium
where does the upper limit of the heart reach
as high as the third costal cartilage on the right side of the sternum and the second intercostal space on the left side of the sternum
the right margin of the heart extends from…
the right third costal cartilage to near the right sixth costal cartilage
the left margin of the heart…
descends laterally from the second intercostal space to the apex located near the midclavicular line in the 5th intercostal space
the lower margin of the heart extends from ….
the sternal end of the right sixth costal cartilage to the apex in the fifth intercostal space near the midclavicular line
a thickened area of connective tissue between the aortic ring and right atrioventricular ring
right fibrous trigone
a thickened area of connective tissue between the aortic ring and the left atrioventricular ring
left fibrous trigone
circles the heart, separating the atria from the ventricles
coronary sulcus
what is found in the coronary sulcus?
right coronary artery
small cardiac vein
coronary sinus
circumflex branch of the left coronary artery
consists of three semilunar cusps with free edges projecting upward into the lumen of the pulmonary trunk
pulmonary valve
forms most of the base or posterior surface of the heart
left atrium
which chamber of the heart has the thickest layer of myocardium?
left ventricle
the opening from the left ventricle into the aorta is closed by the ___________________
aortic valve
what valves do you listen to for heart sounds with a stethoscope?
tricuspid
mitral
pulmonary
aortic
heart sound is heard to the left of the lower part of the sternum near the 5th intercostal space
tricuspid valve
heart sound is heard over the apex of heart in the left fifth intercostal space at the midclavicular line
mitral valve
heart sound is heard over the medial end of the left second intercostal space
pulmonary valve
heart sound is heard over the medial end of the right second intercostal space
aortic valve
a potentially life-threatening condition resulting from accumulation of fluid in the intrapericardial space, leading to compromised diastolic filling and cardiac output
cardiac tamponade
what is the first line treatment of confirmed cardiac tamponade
pericardiocentesis
artery that descends vertically between the right atrium and right ventricle
right coronary artery
where does the sinu-atrial nodal branch of the right coronary artery run?
in the groove between the right auricle and ascending aorta
where would the right marginal branch of the coronary artery be found?
the inferior margin of the heart and continues along the border toward the apex of the heart
as the right coronary artery continues on the diaphragmatic surface, it supplies a small branch to the atrioventricular node before giving off the _________________________ branch.
posterior interventricular branch
where does the left coronary artery pass through before entering the coronary sulcus?
between the pulmonary trunk and left auricle
where is the anterior interventricular branch of the left coronary artery found?
it descends obliquely toward the apex of the heart in the anterior interventricular sulcus
what branch of the left coronary artery courses toward the left, in the coronary sulcus and onto the base/diaphragmatic surface of the heart
circumflex branch of the left coronary artery
how would you determine if a heart is right dominant?
if the posterior interventricular branch arises from the right coronary artery
how would you determine if a heart is left dominant?
the posterior interventricular branch arises from an enlarged circumflex branch
where is the sinus (sinoatrial) node located?
between the superior vena cava and right atrium
why is the sinoatrial node called the natural pacemaker of the heart?
it generates impulses automatically by spontaneous depolarization of its membrane at a rate quicker than any other cardiac cell type
what are the 4 basic components of the conduction system that coordinates contraction of the atrial and ventricular muscles?
-sinoatrial node
-atrioventricular node
-atrioventricular bundle with its right and left bundle branches
-subendocardial plexus of conduction cells (Purkinje fibers)
The autonomic division of the peripheral nervous system regulates….
heart rate, force of each contraction, and cardiac output
stimulation of the parasympathetic system….
decreases heart rate, reduces force of contraction, and constricts the coronary arteries
stimulation of the sympathetic system…
increases heart rate and increases the force of contraction
senses alterations in blood pressure and blood chemistry and are therefore primarily concerned with cardiac reflexes
afferents associated with the vagal cardiac nerves
defined as a PR interval exceeding 0.2 sec with preserved 1:1 AV conduction relationship
first-degree atrioventricular (AV) block
characterized by a failure of one or more, but not all, atrial impulses to conduct the ventricles. sinus rate will continue at regular intervals
second-degree atrioventricular heart block
the absence of electrical impulse transmission from the atria to the ventricles when AV junction is not physiologically refractory, due to a functional or anatomical impairment of the conduction system, resulting in a bradycardia characterized by AV dissociation
complete heart block (CHB)
the sinus node and the AV node are supplied by the ____________ in about 60-90% of people
right coronary artery
disease in the right coronary artery can cause?
sinus bradycardia and AV nodal block
Sinus arrhythmia description
variable QRS cycle lengths without change in the P wave-QRS relationship
describe normal sinus rhythm with sinus arrhythmia:
the P-P intervals vary by >0.16 sec
caused by obstructive coronary atherosclerotic plaque which results in myocardial oxygen demand-supply mismatch
stable coronary heart disease
what is the gold standard to definitively diagnose stable coronary heart disease
invasive coronary angiography
how does a heart attack occur
when the perfusion to the myocardium is insufficient to meet the metabolic needs of the tissue, leading to irreversible tissue damage
-usually a total occlusion of a major coronary artery
