Previous
Play
Next
Rewind 10 seconds
Move forward 10 seconds
Unmute
0:01
/
zero:15
Full display
Brainpower
Read More
SA Node
• Intrinsic Pacemaker of the coronary heart
• Rate 60-one hundred beats/min
• RA (Right Atrium), near SVC (Superior Vena Cava)
• Blood supply from RCA (Right Coronary Artery) & LCA (Left Coronary Artery)
Interatrial/Internodal Tracts
Transmits impulses from the SA node to the AV node via the RA & LA
AV node
• Slows conduction (40-60 beats/min)
,• Physiologic delay permits atrial kick on ground of RA near tricuspid valve
Bundle of His
Bundle of cardiac muscle fibers that conducts the electrical impulses from the AV node inside
the right atrium to the septum between the ventricles and then to the left and right ventricles.
Package branches
Right and Left (Left anterior & Left posterior fascicles)
Purkinjie Fibers
Fibers from Bundle Branches imbedded into the ventricle walls.
Depolarization vs Repolarization
Depolarization – electrical excitation of the mobile membrane, typically followed by way of
mechanical contraction
Repolarization – return of cell membrane to its resting nation, usually accompanied by
mechanical relaxation
Electrical and mechanical pastime of the coronary heart
♥ The coronary heart has sports which can be completed rhythmically: electrical pastime
observed by means of mechanical pastime
♥ Electrical hobby constantly precedes mechanical interest
♥ It is feasible to have electrical activity with out mechanical response
♥ Always test the patient - Do Not Depend at the Machine!!!
Measurement of the containers within the ekg
♥ A preferred ECG is outlined at 25mm in keeping with 2d or 25 small squares according to 2d.
Since one 2d divided by means of 25 small containers, then every 1 mm container = zero.04
seconds. The large containers indicated through the heavier traces are equal to zero.20
seconds.
♥ Voltage is measured alongside the vertical axis and is expressed in millivolts (mV). The
general calibration is that a 1 mV signal produces a ten-mm deflection (zero.1 mV=1mm).
Simply positioned 10 small squares vertically is equal to 1 millivolt
, EKG waveforms and durations
♥ P wave – rounded with upright deflection in lead II, atrial depolarization
♥ PR c language- delay @ AV junction
• degree from beginning of P wave to beginning of QRS
• Normal length zero.12 – 0.20 seconds •
S wave – Negative deflection following the R-wave
♥ QRS complex – a couple of additives, Ventricular depolarization, - zero.06 –0.11
• Q wave – first bad deflection after P wave R wave
• Positive deflection after the Q
♥ J factor - marks in which the QRS complex ends and the ST segment begins
♥ ST section – typically isoelectric line between QRS and the start of the T wave
♥ QT c program languageperiod – beginning of the QRS complex to the stop of the T wave;
changes with heart price, typically 1/2 of the R to R c program languageperiod. Starting of vent
activation via Ventricular depolarization. Zero.44 –zero.48 (Rate dependent)
♥ T wave - follows the QRS; normally, large than the P wave and barely asymmetric; Ventricular
repolarization
♥ U wave – now not typically visible, can be due to hypokalemia or digitalis toxicity
Isoelectric Line –No perceived electric modern-day
indication of a flat line at any time within the duration of a series of waves
indicates no electric activity at that precise moment
Nursing Responsibilities when theres changes in ECG rhythm
♥ Print, measure, interpret and submit rhythm strips per unit wellknown.
♥ Get a 12 lead ECG for any rhythm modifications.
♥ Get a set of essential signs and symptoms for any rhythm changes.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Legitexams. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $11.49. You're not tied to anything after your purchase.