ECG Rules Flashcards
Consolidation of ECG Interpretation Rules & Guidelines
Portion on Myocardium supplied by Right Coronary Artery?
Right Atrium
Right Ventricle
Interior Surface of Left Ventricle (85% of population)
Posterior Surface of Left Ventricle (85% of population)
Portion on Myocardium supplied by Left Anterior Descending artery?
Anterior surface of Left Ventricle
Part of lateral surface of left ventricle
Anterior 2/3 of interventricular septum
Portion on Myocardium supplied by Circumflex Artery?
Left Atrium
Part of Lateral Surface of Left Ventricle
Inferior Surface of Left Ventricle (approx 15% of population)
Posterior surface of Left Ventricle (approx 15% of population)
Portion of Cardiac Conduction System supplied by Right Coronary Artery?
SA Node (about 60% of population)
AV Bundle (Approx. 85-90% of population?)
Portion of Cardiac Conduction System supplied by Left Anterior Descending Artery?
Most of RBB
Anterior-superior fascicle of LBBB
Part of posterior-inferior fascicle of LBB
Portion of Cardiac Conduction System supplied by Circumflex Artery
SA Node (40% of population)
AV Bundle (10-15% of population)
Which blockage is referred to as the “Widow Maker”
Blockage of the Left Main Coronary Artery (supplies LAD and CX)
What is the location and result of stimulation of Alpha 1 Adrenergic Receptors?
Receptors are in eyes, blood vessels, bladder, and male reproductive organs.
Stimulation results in constriction.
What is the location and result of stimulation of Alpha 2 Adrenergic Receptors?
Located in digestive system and on presynaptic nerve terminals in peripheral nervous system. Stimulation results in decreased secretions, peristalsis, and suppression of norepinephrine release
What is the location and result of stimulation of Beta 1 Adrenergic Receptors?
Location: Heart and Kidneys.
Result: Increased HR, contractility, and irritability (heart), release of renin into blood (kidneys).
What is the location and result of stimulation of Beta 2 Adrenergic Receptors?
Location: Arterioles of heart, lungs, and skeletal muscle. Stimulation triggers dilation.
What are the two main types of cholinergic receptors, and where are they primarily located?
Nicotinic- in skeletal muscle.
Muscarinic- in smooth muscle
What are the effects of parasympathetic stimulation of the heart? (4)
- Slows rate of discharge via the SA node
- Slows conduction through the AV node
- Decreases strength of atrial contraction
- Small decrease in force of ventricular contraction
Location of chemoreceptors for blood pH?
Internal carotid arteries and aortic arch
What are meanings of chronotropic, inotropic, and dromotropic?
Chronotropic - refers to change in HR
Inotropic- refers to change in myocardial contractility
Dromotropic- refers to speed of conduction through A/V junction
