Triggering on peak of ECG waveform

Hey,
Basically, Ive got to simulate an ECG waveform within labview and then use it to trigger solenoid valves. For now, I am trying to use the highest peak (Point R) to turn on an LED. Firstly, I could only find an ECG simulator on NI which just returns the shape, and not a continuous wave. So with a lot of help from a member of university staff, I have attached a VI where the data was transformed into dynamic and then the amplitude and data number is constantly being read.
I have the following problems:
How can I make the proccess start again after the end of the waveform, as it eventually gives an amplitude of 0 after the data point where the wave finishes.
How Can I make the led come on from the time the graph is at the middle of the 2nd highest peak till it turns off at the middle of the lowest peak, and stays off untill it reaches the middle of the 2nd highest peak again, and so on....?
I thought of 2 ways, firstly to find the highest peak and use equations based on the BPM (note: the vi given is for 60BPM) to offset the triggers on the 2nd and lowest peaks. And a much simpler,; to find the requied peaks by finding peaks within a certain threshold range. But how can i look for a peak within a range of amplitudes? The find peaks and valleys function only has one threshold input.
Thanks in advance
Attachments:
Untitled 1.vi ‏60 KB

Thanx for the reply. the data is attachted.
I got it from exporting data from a graph using the vi from http://zone.ni.com/devzone/cda/epd/p/id/6188
What im stuck on is triggering/ turning an LED on (for example), by triggering from the highest peak. Also the other problem, which I need to tackle first is how do I make the ECG wave continuous. I couldnt find a continuous waveform ECG, so I used that one, and converted it like i have, but after that wave finishes then the amplitude is zero, but i want the wave to continue, or restart, in order to be able to trigger on the peak, and then keep the led on until the 2nd highest peak, when it is turned off.
Let me know if I have not explained something properly.
And I have now taken off the overall while while loop, but theres no point me attaching that, thers no change to the output.
Attachments:
Datacsv.csv ‏654 KB
Data.xlsx ‏575 KB

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I am currently using Labview 8.0. In that i am facing problems in detecting the peaks of an acquired waveform graph. I tried using the threshold peak detector.vi in the function palette but it doesnot work for me.I also tried filtering the waveform and detecting the peaks but still there was no result. I have uploaded the text file of my waveform here. Can anyone tell me how to detect the peaks of this waveform.
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Attachments:
hhaft.TXT ‏723 KB

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Triggering on peak of ECG waveform

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