1 Flashcards
(19 cards)
Anterior versus posterior
ANTERIOR: part of the heart that lies behind the sternum, predominantly right ventricle. POSTERIOR: part of the heart facing the diaphragm, predominantly left ventricle.
Right versus left atrium
RIGHT ATRIUM: receives blood from superior and inferior vena cavas. LEFT ATRIUM: receives blood from pulmonary veins.
Pulmonary artery versus veins
PULMONARY ARTERY: carries poorly oxygenated blood from right ventricle to lungs. PULMONARY VEINS: carries richly oxygenated blood from lungs to left atrium.
Sinoatrial/SA node
located where right atrium and superior vena cava meet
Atrioventricular/AV node
located in the right atrium
Polarization versus depolarization versus repolarization
POLARIZATION: resting state; no electrical activity occurs. REPOLARIZATION: flow of electricity that triggers positive charge of electrons and heart contraction. REPOLARIZATION: negatively and positively charged ions return to original places.
Inherent rates (at rest)
SA NODE: 60-100 bpm. AV NODE: 40-60 bpm. VENTRICLES: 20-40 bpm.
Sympathetic versus parasympathetic nervous system
SYMPATHETIC NERVOUS SYSTEM: affects atria and ventricles; increases heart rate. PARASYMPATHETIC NERVOUS SYSTEM: affects only atria; decreases heart rate.
Veins versus arteries
VEINS: blood vessels returning blood back to heart. ARTERIES: blood vessels carrying blood away from heart.
Normal heart measurements
NORMAL PRI: 0.12 to 0.20 seconds. NORMAL QRS INTERVAL: 0.04 to 0.12 seconds. NORMAL QTC INTERVAL: 0.35 to 0.43 in males and 0.35 to 0.47 in females.
60-cycle interference
A 60-cycle interference causes thick wave lines and the culprit is usually a power cable located under the patient’s bed.
Heart stimulation
ABSOLUTE REFRACTORY PERIOD: no stimulus will lead to depolarization. RELATIVE REFRACTORY PERIOD: strong stimulus will result in depolarization. SUPERNORMAL PERIOD: weak stimulus will cause depolarization; results in dangerous rhythms.
Bachman’s bundle
structure that electrically connects the right and left aria
T wave versus P wave
T wave represents ventricular repolarization. P wave represents atrial depolarization.
Purkinje fibers
specialized nerve cells within the conduction system that rapidly trasmit electrical signals
Myocardium versus endocardium
MYOCARDIUM: layer of the heart that is primarily concerned with contraction. ENDOCARDIUM: layer of the heart that contains most of the conduction system.
Sinus arrest versus sinus exit block
SINUS ARREST: off caliber hop. SINUS EXIT BLOCK: on caliber block.
Triad of danger
- LQT 2. ROT 3. TDP
Ventricular bi/tri/quadrigeminy
VENTRICULAR BIGEMINY: PVC every 2nd complex. VENTRICULAR TRIGEMINY: PVC every 3rd complex. VENTRICULAR QUADRIGEMINY: PVC every 4th complex.
