Deep dive tachycardia, or panic?

[Madhiker_99]

I suggest you and your doctor consider ordering a "CT Calcium Test." Here's why.

Some years ago after performing triathlons I had similar racing heart rate experiences in which I felt dizzy and faint while standing around to find out results. I was a diver, too. Like you, I couldn't reproduce the dizziness with standard doctors' treadmill tests. After a nuclear stress test and gathering Holter monitoring data, the best my doctor could suggest was that I didn't properly cool down after significant exercise. My experience was slightly different from yours, however, in that I never had the "dizzies" while diving, and not even on dive trips.

But I had come across a Runners World article that led to a different diagnosis and solution. The point of the article was to recommend a "CT Calcium Test" to look for the extent of cholesterol loading (calcium deposits are markers of cholesterol). So we arranged for the test. The test result of 505 (out of 1000) indicated a dangerously high level of coronary plaque that required immediate intervention. That was a big surprise all around, and I was promptly put on a regemin of aspirin and a statin, and an angiogram was ordered.

The surgeon conducting the angiogram determined that an artery to the heart was 90 to 95% closed, so he inserted a stent. It manages the risk of collapse, and the medications mitigate against further build up of cholesterol.

After recovery, my doctor, who was formerly a diver, consulted on a conference call with a professional diving friend and a DAN doctor. Their conclusion was that there was nothing to "contraindicate" continuing to dive, provided I remained alert and careful, kept fit, and stayed in good health. I continued diving, and I've had some great adventures, but no heart problems. Even so, I still get occasional slight dizziness, or fizzy headed, especially when I stand up too quickly.

The upshot of my story for you is that my problem's cause was not discovered using heart rate testing. Consider an getting angiogram.

Wow... very eye opening, and I greatly appreciate you sharing this info.

Thanks much, and it's on the docket for discussion w/ my cardiologist!

 

[Madhiker_99]

If the OP has early symptoms of atrial fibrillation, and is only having brief episodes (seconds to minutes of tachycardia), he would be much more likely to capture an EKG and a diagnosis by using a home EKG like I linked above. By the time he gets one elsewhere he may be back in normal rhythm.

My advice would be do the home EKG, then immediately go get an EKG at Urgent Care, or a Doctors office.

The reason this is important for someone interested in continuing vigorous exercise in the future is that statistically the longer one has had intermittent Atrial Fibrillation the less likely intervention like ablation is curative.

Thanks for these details. Great info, and much appreciated!

 

[Duke Dive Medicine]

Thanks for the reply. I’ve had tachycardia from too much alcohol. Reviewed by my cardiologist which included echocardiogram that found no damage. Recommendation was - stop drinking too much! Easy fix.

Heart was racing very fast during dive episode. I estimate 150 bpm, which caused fear of heart attack, likely further aggravating the panic.

Thinking the narcosis, plus restricted blood flow from pressure, caffeine, etc are likely culprits. All things for me up consider next time. Along with other responses to this thread.

Best!

I was going to mention the possibility of atrial fibrillation and then read on to see @FishWatcher747 's posts. He covered it pretty well, but just for the sake of posterity, a-fib is a rhythm where the atria (the top chambers of the heart) essentially just quiver rather than contracting rhythmically and pumping blood down to the heart's ventricles. Since the blood can get stagnant in the atria, there's a risk of it clotting, and then when the rhythm converts to normal sinus rhythm, the clots can get ejected and end up in the lungs, brain or elsewhere. The problem, as @FishWatcher747 pointed out, is capturing it on an ECG as it happens and diagnosing it. If it's infrequent, it's really hard to catch. Atrial fibrillation is typically an irregular heart rhythm, but at a rate of 150 it can be hard to tell regular from irregular without an ECG tracing. The SVT that @rsingler mentioned is another possibility, but again if it's paroxysmal (only happens irregularly) it can be hard to capture. Not to add anything to your bucket of things to be concerned about, but it may not be a bad idea to at least consult your PCP about this, and then maybe he/she can refer you to a cardiologist if necessary.

Best regards,
DDM

 

[Madhiker_99]

I was going to mention the possibility of atrial fibrillation and then read on to see @FishWatcher747 's posts. He covered it pretty well, but just for the sake of posterity, a-fib is a rhythm where the atria (the top chambers of the heart) essentially just quiver rather than contracting rhythmically and pumping blood down to the heart's ventricles. Since the blood can get stagnant in the atria, there's a risk of it clotting, and then when the rhythm converts to normal sinus rhythm, the clots can get ejected and end up in the lungs, brain or elsewhere. The problem, as @FishWatcher747 pointed out, is capturing it on an ECG as it happens and diagnosing it. If it's infrequent, it's really hard to catch. Atrial fibrillation is typically an irregular heart rhythm, but at a rate of 150 it can be hard to tell regular from irregular without an ECG tracing. The SVT that @rsingler mentioned is another possibility, but again if it's paroxysmal (only happens irregularly) it can be hard to capture. Not to add anything to your bucket of things to be concerned about, but it may not be a bad idea to at least consult your PCP about this, and then maybe he/she can refer you to a cardiologist if necessary.

Best regards,
DDM

Thanks for the info. I see a Cardiologist regularly, and after reading all of these amazing recommendations, I'm contacting him now for his recommendation.

I am truly awed by the outpowering of info and reminded of how amazing our dive community is. Especially when needed the most!