Chemical Stress Test wihle in AFIB

I'm scheduled for a nuclear chemical stress test as opposed to a treadmill type of stress test.
My heart rate will be elevated by drugs rather than exercise. I'm thinking the drug induced high
heart rate is more dangerous for me in afib than an exercise induced high heart rate. I routinely
engage in fast walking punctuated with several 1/4 mile jogs that elevate my heart rate. I never
experience any pain or shortness of breath other than what is expected when pushing hard while
in afib. My resting afib heart rate varies from 55 - 85. My concern is the drug could cause ventricular
fibrillation. Anyone have any experience with a chemical stress test while in afib?

I wasnt in afib and refused the chemical vs treadmill. I had no problem sustaining 170 BPM for the time needed. Passed it. IMO, Id take the treadmill. Either way, your HR will be elevated.

I had one while in afib, and didn't feel a thing. Unfortunately, that was considered "highly abnormal" and my local EP ordered me to take an angiogram..which showed no problems. I figured as much, since I didn't have any symptoms despite a lot of exercise.

I don't think there's anything about a chemical stress test that makes it more dangerous than a treadmill. There's no reason to think it would lead to v-fib. Afib just doesn't lead to v-fib.

Carey-

I'm not concerned that afib will lead to vfib. I'm concerned that the drug given to speed up your heart rate could
produce vfib. After looking at several respectable websites on chemical stress testing, I find that vib, while rare,
can occur as a result of the stress drug.

Given the choice I would push to have the treadmill stress test done. I had a chemical stress test done many years ago because I was in AFib at the time of the test. It was not a pleasant experience for me at all.

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LarryZ
Carey-

I'm not concerned that afib will lead to vfib. I'm concerned that the drug given to speed up your heart rate could
produce vfib. After looking at several respectable websites on chemical stress testing, I find that vib, while rare,
can occur as a result of the stress drug.

Okay, but it's not the drug; it's the stress test itself. In those individuals who experienced vfib, they most likely would have had the same outcome on a treadmill. Personally, I would prefer a treadmill, but not because I fear the drug. I would prefer it simply because when you get off the treadmill it's done. There's no waiting for the drug to wear off.

I have some serious doubts as to whether chemical stress tests should be done at all in persons with a history of atrial fibrillation.
This is based on the article: FDA warns of rare but serious risk of heart attack and death with cardiac nuclear stress test drugs Lexiscan (regadenoson) and Adenoscan (adenosine).

FDA Bulletin

The FDA bulletin points to serious concerns about Lexiscan (regadenoson) and Adenoscan (adenosine). It also points out that dobutamine is not approved for this use in the USA.

Particular attention is called to the phrase "cardiac instability" in the article. I think atrial fibrillation easily fits into this category.

Dipyridamole is approved. However, this drug seems to be aimed at an anticoagulant use, rather than as a cardiac stress test drug.
Some of the adverse effects of dipyridamole are:
Chest pain/angina - 19.7 Percent
Headache - 12.2 Percent
Dizziness - 11.8 Percent
Electrocardiographic Abnormalities - 12.7 Percent

According to the Journal of the American College of Cardiology, exercise cardiopulmonary stress testing in Afibbers has some uncertainty also.

JACC Stress Testing article.

Sorry if I have kicked over the bee hive, but these are aspects of cardiac stress testing that I have wanted to discuss for a while.



Edited 1 time(s). Last edit at 08/30/2018 10:11PM by Jim Benton.

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Carey

Carey-

I'm not concerned that afib will lead to vfib. I'm concerned that the drug given to speed up your heart rate could
produce vfib. After looking at several respectable websites on chemical stress testing, I find that vib, while rare,
can occur as a result of the stress drug.

Okay, but it's not the drug; it's the stress test itself. In those individuals who experienced vfib, they most likely would have had the same outcome on a treadmill. Personally, I would prefer a treadmill, but not because I fear the drug. I would prefer it simply because when you get off the treadmill it's done. There's no waiting for the drug to wear off.

Ugh, really? I dont want to be the anti med nut here, but you have the chance to refuse a med for a natural method with less side effects. Point is if I feel impacted on a treadmill, I jump off. With the med, it has to jump off.

I've had nuclear chemical stress tests on two occasions. Because of mobility problems, I cannot do the treadmill. I did not find the nuclear stress tests to be unusually hard or uncomfortable. They do take a while longer generally because of the medicines. I am sure there are others in this forum who cannot take the treadmill test for various reasons....and the nuclear stress test is the alternative.

Good points Jim Benton -

With your research, did you learn the length of residual time the chemical remains in the body?

Jackie

Thanks, Jackie.

The half-life of Lexiscan (Regadenoson) is listed as two to four minutes, while the half-life of Adenoscan (Adenosine) is listed as ten seconds.

For both drugs, most adverse reactions began soon after dosing, and generally resolved within approximately 15 minutes, except for headache which resolved in most patients within 30 minutes.

No experience with Lexiscan but I've seen adenosine administered many times and received it myself three times. It's over within about 10 seconds and has no lasting effects. It's a natural substance produced by your own body.

The article posted about stress testing afibbers involved heart failure patients and isn't very applicable to those without heart failure.

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Carey

The article posted about stress testing afibbers involved heart failure patients and isn't very applicable to those without heart failure.

A rather meaningless term. The test is to find out what is going on. As you can see, there are a large variety of varying responses.

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jpeters
A rather meaningless term. The test is to find out what is going on. As you can see, there are a large variety of varying responses.

Heart failure is a meaningless term? Um, no. Perhaps I misunderstood you?

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Carey


Heart failure is a meaningless term? Um, no. Perhaps I misunderstood you?

Been through it before on another thread, with references to the chief editor of a major journal on cardiology. The common term is "structural heart disease" which can cover a vast number of possible causes that need to be determined prior to administering treatment. It is not a "cause" of anything in itself, in that it's just a concept.

"Heart Failure" is even more general. What caused it? To what degree is the heart "failing" ? My guess is that anyone who sustains persistent afib for a few months will show decline that could be labeled "heart failure."



Edited 2 time(s). Last edit at 09/02/2018 01:25PM by jpeters.

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jpeters
"Heart Failure" is even more general. What caused it? To what degree is the heart "failing" ? My guess is that anyone who sustains persistent afib for a few months will show decline that could be labeled "heart failure."

Structural heart disease is indeed a very general term, but heart failure is not. Heart failure is a very well defined entity with specific diagnostic criteria. What caused it is beside the point, but that's usually known and AMI is the most common cause. The degree to which the heart is failing very much measurable. I have no idea where you got the notion that it's not.

Persistent afib for a few months does not cause heart failure as long as the rate is controlled. Millions of people live with persistent afib for decades and never develop heart failure as long as they keep the rate under control. Yes, lack of rate control can lead to heart failure with persistent afib and flutter, but it doesn't necessarily and that shouldn't happen to anyone receiving proper care.

I've treated heart failure, and I've seen people die of it. If you think the heart isn't literally failing then you don't understand what heart failure is. There are types and degrees of HF, and at the more severe end of the scale the failure can be dramatic and rapidly lethal (minutes).

Carey, I never said there were no measures of "heart failure." That's what an echo is about, and you can certainly see declines even on rhythm control meds when in persistent afib. I did, which is why I opted for an ablation.

Why would anyone want to have radioactive material injected into your body? I’m newly diagnosed with AFib and my cardiologist schedule a Lexiscan nuclear stress test for me, even though I’m perfectly able to walk on a treadmill. After researching Lexiscan, I found this: “Important Safety Information

Lexiscan should not be given to patients who have certain abnormal heart rhythms unless they have a pacemaker.
Lexiscan can cause serious or fatal cardiac arrest, abnormal heart rhythms or heart attack.”

Naturally, I cancelled that immediately.

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Lindy
Why would anyone want to have radioactive material injected into your body? I’m newly diagnosed with AFib and my cardiologist schedule a Lexiscan nuclear stress test for me, even though I’m perfectly able to walk on a treadmill.

I think that's injected into your body either way, since they take pictures of your heart before and after the stress load. I was instructed to bring fatty food to help clear it out as soon as possible.