The RR interval is the time between each R wave (i.e.
Ultimately the question you are asking is whether or not the QRS complexes are regular.If the rate is too slow, it suggests that there is something abnormal about the conducting system of the heart.I remember it simply in terms of the directions the leads face.It is read as a single bump following the QRS complex.Working out the rate is quite easy.
The direction that each of the leads is pointing in gives you the information convert foot pounds to kilograms per meter about direction.
Usually this will be easier to work out from another part of the ECG, but it can slow down the rate, and a slow rate should therefore be a prompt to look out for such abnormalities in the rest of the ECG.
Let's work through the examples.
A prolonged QT can be from birth - 'long QT syndrome'.This is first degree heart block.Other times, it may be that the PR interval gets longer and longer until eventually no QRS complex follows (and then it starts back at the beginning again this is called "Wenkebach phenomenon or Mobitz Type 1 second degree heart block.The usual paper speed is 25mm/sec : 1mm ( small square ).04 sec 5mm ( big square ).2 sec, if a different paper speed is used, calculations will have to be modified appropriately.The "M" shape happening in the lead V6) because it may be a sign that someone has just had or is having a heart attack.All information is provided for the sake of personal interest and academic study, and should not be used as an alternative to the personalised advice of a qualified medical professional.It is an important delay, because it prevents the heart from beating too quickly, and ensures regulated activity.If there is no downward deflection before the R wave, then there is no Q wave.It is called heart block.Understanding how to calculate it requires an understanding of the ECG itself; if the cardiac axis faces the same direction as the leads, the QRS complex in that lead will be mainly positive.