some help required for research on RR interval in ECG

Hello to group members,

I am doing research on detection of paroxysmal atrial fibrillation (PAF) from continuous ECG recorded signals, I would like to know that following :

1. R-R shorten to what extent from normal (i.e say normal RR interval is X millisecond so in PAF is it X/3 or X/4 milliseconds ??)

2. Say in 5 min ECG recorded signal for how many RR intervals are considered for saying that any patient is having PAF( i.e if in 5 min of recording say only 1 RR interval is short than previous, so does it qualify to be called PAF patients. In other words how many abnormal intervals should be considered ???)


8 Replies

  • The RR abnormal intervals need to be consistently different from one another to be called AF. If only one was different/shorter, that would just be an ectopic beat.

    Shorter intervals between RR does not determine PAF. If those shorter intervals were all irregular then that is PAF. Shorter but regular intervals could be SVT.

    PAF /AF can be at a slower rate, it is the irregulararity that makes it AF.

    Am I interpreting your questions as you intended?

    If not ask again.


  • thanks for prompt reply.

    Well what i conclude its about " irregularity". But can we measure this irregularity or What can be the units of this irregularity??

    For example we say the weight of any person is 80 pounds , so pounds is a unit for measuring weight. Now, We can compare that this person's weight with any other and say he can be 20 pounds more heavy than other.

    Similarly in case of irregularity can we measure the regularity and compare??


  • I fear you are missing the point here. An ecg trace with AF shows no p wave and THAT is the criteria along with irregular and irregular beats. I once heard a GP ask a specialist when groups of ectopics became AF. They obviously didn't understand what AF was either as the specialist explained. Pat is right.


  • As a courtesy to group members, please could you explain whether this is personal research or on behalf of an organisation? Where is the research leading?

    For my benefit, what is an RR interval?

  • this is a personal research just to detect PAF cases in advance so that some lives can be saved. Mortality rate is high due to PAF and PAF can also leads to stroke in some cases. I am a student.

    for RR interval Please refer

  • Thank you for clarifying

  • Just out of interest why do you think PAF has a high mortality rate?

    The increased risk of stroke is understood.

  • "The mortality rate from atrial fibrillation, whether it’s the primary cause or an underlying cause of death, has been rising for more than 20 years.

    An estimated 2.66 million people will have atrial fibrillation this year (2010) and that number will more than quadruple to as many as 12 million by 2050"

    taken form this article .please read full article here

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