Pulse sudden jump 120 to 225 during excercise

[cascas737]

I have started to use a heart rate monitor at the gym. My pulse at rest was about 65, would increase to 90, 100, 110, 120 and then suddenly jump to 224. If I slow down/rest it will drop down to 120 again in an instant.

The sudden jump from 120 to 224 happens every time, and I have no symptoms when this happens. At first I thought the monitor was faulty, and have tried 2 others with the same results.

When walking the pulse seems to quickly rise to 120 and they stay at this level, until it work harder and it jumps to 224. If I stop and feel the pulse in my neck it is very rapid and light, and then if I wait I can feel stronger, slower beats come in and the watch displays 120 again.

When born, I was diagnosed with a heart murmur (innocent),  with periodic check-ups until 16 where I was told that no further follow up was required. I used to have a slow resting pulse (50bpm)

Could this be AVNRT, or something else?

[tom_h]

I had AVRT, and mine didn't do that.  All kinds of things would get it going,  and heavy physical exertion was a common trigger.  But subtle things like stepping off a curb and accidentally landing flat-footed would cause a momentary vibrational shock through my body, and that could do it.  Another trigger was twisting my torso such as rolling over in bed, or getting out of the car.  So I could be at rest or under physical stress and it could go off.  But one my SVT started, I had the run-on variety.  It'd just keep going and going.  Only once in my life do I recall it spontaneously converting as you report yours doing  I would have to intervene by doing Valsalva to slow it down, or I would have been at the hospital ER literally hundreds, thousands of times.

[cascas737]

Thanks for all your comments. Waiting to get an appointment.

I have noticed that by resting pulse is higher than it used to be (used to be around 50bpm, now 65-70bpm), when walking about/up stairs/treadmill at 3mph, pulse increases quickly to 118-120 just stays in this range (like it cant get any higher, until bang, it jumps to 230 and SVT. stopping just as quickly when I stop excercise.

Has anyone else where avrnt or avnt, experienced anything similar?

[littlegreenman1]

My SVT was not detected on Holter or on the 12-lead EKG when I was not in SVT. It was an anomalous pathway of AVNRT.  Not WPW.

My onsets were quick and recovery (usually) just as fast. It happened about every 2nd or 3rd run. It was unrecoverable (>30 mins) on two occasions that sent me to the ER.

Ablation... WORKED !!

I started training 2 weeks later. I have 5 marathons on this heart and 2 more this spring. I have done heavy speed work and after my cardiologist gave me the thumbs up - I went out and "tempted the Devil" with speed work.  If there was a failure - I wanted it in the same calendar year!!  Nope. Not a blip of SVT since 2010.

[tom_h]

In most cases, an EKG of a person with AVNRT outside of an episode will look perfectly normal.

An EKG of a person with AVRT outside of an episode MAY show a telltale slur on the upstroke of the R or on the downstroke of an S wave, as people with Wolff Parkinson White may have.  MIne had a faint slur, but was missed by many.  I did not have WPW but another form of AVRT.

This is why people who report rapid heart rate with a breathless feeling but who show a perfectly normal EKG often are misdiagnosed with anxiety disorder.

[cascas737]

Thanks littlegreenman1,

It is very similar. Very rapid increase from rest to 120 (in your case 160) where it remains constant, and then sudden increase to above 200. Assume you then stopped/slowed down where it when dropped back.

Question for all of you with AVNRT, is the ecg normal outside of the periods of SVT, or is it only detectable when the pulse is high.  ie can the avnrt cause changes in the pulse, or how quick the pulse responds to exercise.

Secondly, after ablation does it have any side effect to the  resting pulse or how you respond to exercise.  i.e can you train as normal.

[littlegreenman1]

Click on my picture. That's a graph of a multi SVT episode I had a few years back while running.

AVNRT. I'm fixed and good to go.

[tom_h]

Absolutely describe the event as you have done here.  It could also be my "favorite" form of SVT called AVRT which has the same characteristics as AVNRT.  Google both of them and learn because bets are that you have one of them.  This isn't a structural issue with you heart, but an electrical problem.  It is very treatable with a procedure called cardiac ablation.  Drug therapy can also be used, but has mixed success.

[MichelleP_3811]

Well actually the way you describe it it is not a gradual slow down.  Bang and it is 120 again means it is also stopping on a beat so it sounds like you have an accessory pathway svt that is somehow triggered by your exercising.  It is not normal for the beat to suddenly start and stop great speeds as you are experiencing.  Though in a healthy heart it is not a danger to you but you will want to consider an ablation to eliminate/block the extra muscle fiber that is conducting the fast beat.  Essentially because of the extra muscle fiber the heart beat signal is getting caught in a loop thus creating the fast beat.  The exercising may be triggering some ectopic beats, an extra beat in the atria or ventricles as well in the cool down which is disrupting the normal signal duration thus triggering/causing the beat  to get caught in a loop and subsequently get out of the loop on cool down though you will need to get this properly diagnosed but the procedure to fix it is very highly effective at curing avnrt if that is what you have and the complication rate is really almost nonexistent.  It is something you can live with though I would highly recommend stopping the exercising when it does happen but It is not something that will go away as well it tends to get worse as you age which is probably why you are sensing it more now in your 30s.   So you may want to seriously consider the ablation to cure it.  It may seem a bit scary to do but when all is said and done an ablation is really not that bad.  I had 2 abdominal surgeries that give me nightmares and the ablation really was a piece of cake.  If you want to read about mine click on my name and read my journal entry.  Anyways make sure when you describe what you are feeling to your cardiologist that you tell them it starts and stops suddenly.  This should clue them into looking for avnrt.  Take care.

[cascas737]

Thanks for your replies. The pulse doesn't slow down gradually. The monitor displays 224 etc, i stop exercising, it continues at 224 for a few seconds (i.e 20 seconds), and then "bang" it goes back to 120.

It it usual in tacycardia for the pulse to jump suddenly as I am experiencing?

If I wouldn't have used a hrm I would not notice any symptoms (hence thinking the monitor was faulty).

[MichelleP_3811]

The rate does sound like classic avnrt.  Mine would go to 230 or so.  Though it was very random when it happened and it would start and stop on a beat.  You say yours starts fairly instantaneously but gradually slows which doesn't totally fit avnrt but considering it happens every time you exercise it should be easy to capture and diagnose.  I would say make an appointment with a cardiologist and explain everything as you have explained and get this figured out.  If it is avrnt there is a very easy fix for it with an ablation.  Good luck and keep us posted on how you are.

[is_something_wrong]

You are describing textbook AVNRT. But for getting a diagnosis and treatment, please ask your doctor for a stress test. It's good that you don't have a lot of symptoms, but please get this arrhythmia under control. No need to suffer when treatment is available!