cardiology Flashcards
the heart is supplied by
the left and right coronary arterie s
At whatBlood flow to the myocardium occurs
mainly during diastole
Compared to other veins, the oxygen saturation in coronary venous blood is very low (often O2 saturation of only 35%). This is because…
oxygen extraction by the heart muscle is very high
Where is oxygen extraction by the heart muscle is very high
inferior surface of heart
released upon cell activation and contains a high conc of a molecule that acts as an agonist
platelet dense granules
responsible for apex beat in midclavicular line
left v
prevents backflow of blood in ventricular systole
mitral valve
carries oxy blood from lungs to left side of heart
pulmonary vein
prevents high pressures developing in the jugular veins during ventricular systole
tricuspid valve
carries deoxy blood back to the right atrium
inferior vena cava
ventricular repolarisation is what wave
t wave
normal duration120 to 200 for what interval
pr interval
asseses the electrical activity within lateral myocardial territory
j leads
what is the definition of membrane potential
difference in electric potential between the interior and exterior of a cell
define blood flow
the volume of blood that flows through the systemic circulation
What is anemia hypoxia
Blood defect that occurs when the bloods ability to carry oxygen decreases
What is sickle cell anemia
Inherited blood disorder
Not enough healthy Rbc to carry oxygen throughout the body
Lifespan of a platelet
7-10 days
Contents of platelets
Plasma membrane Cytoskeleton Dense tubular system Secretory granules Water Albumin Transport proteins
Two types of bleeding
Platelet or haemophilia
Types of platelet bleeding
PetechiaL rash
Surface of skin
Haemophilia bleeding types
Large suffusions
A b c haemophilia
Muscle or joint bleed
What is thrombocytopenia
Condition in which you have low blood platelet count
What and where is the apex beat
Strongest heartbeat
Left 5th intercostal space
Mid clavicular line
Right heart border ?
Svc and right atrium
Left heart border ?
Aortic knuckle
Left pa
La appendage
Lv
Anterior heart border
Right ventricle
Posterior heart border
Left atrium and pulmonary veins
What divides the posterior and inferior mediastinum
Plane between sternal angle , t4/5
Contents of superior mediastinum
Descending aorta Oesophagus Thoracic duct Azygos vein Vagus nerve
Role of vagus verve
Motor - innervate muscles of the pharynx
Sesnosry - for the epiglottis
Function of papillary muscles
contract during systole to prevent prolapse of the valve into atria
Function of chordate tendinae
Help to maintain and support the position of valves
What is cardiac tampendade
Extra fluid in the pericardium
Function of Christa terminalis
Anatomic conduction barrier
Where does the coronary sinus drain blood into
Into the right atrium
What is the fossa oval is
Remains of the foremen ovale which was patent in foetal life which separated the two atria
Where do the coronary arteries run
In the grooves such as between ventricle and atria
What does the left main stem coronary artery brain into
Lad and circumflex artery
What does the right main stem coronary artery branch off into
Acute marginal
PDA
What groove does the LAD run in
Anterior interventricul groove
Principal site of resistance to vascular flow ?
Arterioles
Pulse pressure ?
Systolic _ diastolic pressure
Most potent vasoconstrictor
Endothelin-1
Where are the primary baroreceptors located
Carotid sinus and aortic arch
Anp?
Atria natriuretic peptide
how does skeletal muscle differ from cardiac
Cardiac muscle is striated, branching and contains intercalated discs- these features
are not found in skeletal muscle
define tachycardia and bradycardia
tach - bmp over 100
brady bmp less than 60
What causes blood to flow closer to the skin
Vasodilation
Which layer of blood vessels contain endothelial cells that reduce the friction of blood
Tunica intima
