Cardiology Flashcards
(203 cards)
Name the 4 valves in the heart
Mitral valve/ Bicuspid valve (left atrium -> left ventricle)
Aortic valve (left ventricle, exit)
Tricuspid valve (right atrium -> right ventricle)
Pulmonary semilunar valve (right ventricle, exit)
When is blood supply to the heart at its lowest?
During systole
-heart contracted
-high pressure
Pulmonary circulation provides blood to the…
Lungs (and back to the heart)
Systemic circulation provides blood to the…
Systemic tissues (and back to the heart)
Is pulmonary circulation provided by the left or right ventricle?
Right
Is systemic circulation a low or high pressure system?
High pressure
In normal instances, do cardiomyocytes have an aerobic or anaerobic metabolism?
Why?
Aerobic
Name the 2 types of cells of the myocardium
Contractile
Conducting
Cardiac muscle cells are (2)
Electrically excitable
Capable of contraction/relaxation
Properties of cardiomyocytes (4)
Striated muscle fibres
Intercalated Discs (Gap Junctions)
Under involuntary control
Have branches
Are human cardiomyocytes single nucleated or multi nucleated?
Single nucleated
What is the purpose of gap junctions?
Gap junctions allow cardiomyocytes to communicate electronically
What is the effect of elevated Ca2+ on the cardiomyocyte?
Muscle contracts
Name the 3 regions of the heart that can spontaneously generate an action potential
Sinoatrial node (SA node)
Atrioventricular node (AV node)
Purkinje fibres
In the heart, AP travel from: (6)
- SA node
→ Atria
→ AV node
→ AV bundle (bundle of His)
→ Left and right bundle branches
→ Purkinje fibres
3 distinct waves of the ECG & what they stand for
P wave: atrial contraction
QRS complex: ventricular contraction
T wave: ventricular relaxation
What is Einthoven’s triangle?
A theoretical representation in electrocardiography to explain the relationship between the electrical activity of the heart and the placement of electrodes on the body.
What is the electrode position in Einthoven’s triangle?
Right arm (RA)
Left arm (LA)
Left leg (LL)
What is the lead positioning in Einthoven’s triangle?
Lead I: LA - RA
Lead II: RA - LL
Lead III: LL - LA
Einthoven’s Law
Lead II = Lead I + Lead III
Used to verify the consistency of the ECG readings
Is a depolarisation wave travelling towards the positive electrode is a positive or negative deflection?
Positive deflection
Normals QRS axis is in what range in the electrical QRS axis of the heart?
Between -30 and +90 degrees.
Positive deflection in aVF, positive deflection in lead I
LAD is in what range in the electrical QRS axis of the heart?
Between -90 and -30 degrees.
Negative deflection in aVF, positive deflection in aVL, positive in lead I.
What is systole?
Phase of contraction