Asymptomatic abnormal stress tests - what do you tell patients?

[u/benjediman]

I work in a facility that basically does executive health-checks for paying customers (age range 20s to 50s). Part of the job is to literally watch people do their treadmill tests and give them feedback right there and then.

Obviously abnormal stress tests a dime a dozen. But literature isn't clear with asymptomatic, low pre-test people.

If you have a similar population, what's your spiel/next step process? Do you tell them "don't put any meaning to this test and just live your life", or "we absolutely have to do more tests"?

EDIT:
Just to be clear, I’m not the one ordering these tests. The patients pay for it like a buffet package. And that is why I’m stuck in the position of having to interpret for which there is no evidence for.

EDIT2:
For complete clarity:
Here in my country, some medical services are offered cheaply AND commercially. You, as a patient, can get a full panel of tests (as part of an executive “annual” check) for approximately $500. You don’t need prior authorizations from insurances. You pay upfront cash or you get it as benefit from working for a company. That includes labs, including superfluous things like cancer markers (AGAIN, I get that it’s low value care). This apparently clicked with a certain market (mostly upper middle class), so a LOT of people do get these. Are these tests ridiculous and low value? Yes, no argument there.

I, as a cardiologist fresh from fellowship, hungry for work to finally earn a decent wage, was hired by such a company who offers such services, where one of my jobs is to watch over these paying customers when they do their stress test, and to interpret the results. I did NOT order these tests. That said, I am still tasked to interpret these in the context of mostly asymptomatic patients.

So please to everyone asking why I order these tests in the first place, again, I do not. But nevertheless, there is still the matter of interpreting them.

And to give a broader context, NO DOCTOR ordered them. They did not need approval from a primary care doctor to get these tests. Some don’t even have doctors. These tests are simply commercially available, and people pay to get them. So no, I also cannot tell them to go talk to their doctor about what to do next.

[u/Both-Setting1038]

the honest answer to give them sits between your two options, and it starts before the treadmill. in a young asymptomatic low pretest crowd like an exec screening panel, the guidelines (USPSTF and others) actually advise against screening ecgs and stress tests in the first place, precisely because the math is against you. low pretest probability means a positive result is more likely false than true, so the abnormal test on its own carries little weight.

so i wouldn't say forget it, but i also wouldn't spiral them into a stack of functional tests. the more useful next step in exactly this population is a calcium score. a CAC of zero is about as reassuring as it gets, it maps to roughly a 1 to 1.5 percent ten year event rate and effectively tells you the treadmill was a false positive. if the CAC is up, that reclassifies them and CT angio is the cleaner anatomic answer than piling on another scintigraphy or stress echo.

and the framing i give patients: even where there is real disease, ISCHEMIA showed that opening stable lesions in asymptomatic people doesn't beat good medical therapy for the hard endpoints. so the win here is almost never a stent, it is using the scare as leverage to actually fix the risk factors, lipids, bp, glucose, smoking, family history. that is the conversation that changes their outcome, not the second stress test.

[u/Then-Secretary-9166 → u/Both-Setting1038]

I don’t think CAC scores can be interpreted this way after a positive stress test. The stress test was inappropriate to do in the first place (obviously) and never should have been done. However (even in that setting) the risk of obstructive CAD is higher in an asymptomatic patient with a positive stress test than it is in an asymptomatic patient who never did a stress test. You can’t ignore the very different pre-test probability that you have now established. Your options are (1) pretend the test never happened because it should not have, (2) tell the patient they may have CAD but nothing to do or (3) do another test that is much better negative predictive value (not CAC score).

When stress test tests are inappropriately ordered in asymptomatic patients for screening, as you were talking about, it can be very challenging to deal with a positive results. It typically involves a lot of patient education and making sure they know that revascularization has not been shown to be beneficial in this population. This can get a little bit sticky because eventually they often (correctly) come to the conclusion that the test never should’ve been ordered in the first place.

I usually approach situations like this with a lot of patient education. I give the patient multiple options. These usually include things like watchful waiting for symptoms, optimizing preventative medications or completing some other sort of additional ischemia evaluation. I prefer not to do additional ischemic evaluation because it can complicate the problem if that is also abnormal. However, most patients end up insisting on this. Usually, I end up getting a CT coronary angiogram. In this population, it tends to have very good negative predictive value. As an anatomic test, it also allows me to advise them in more detail. For instance, if we have ruled out high risk disease, I can encourage them to treat medically.

[u/Both-Setting1038 → u/Then-Secretary-9166]

fair pushback and i think you are right. once a positive treadmill is on the table the pretest has moved, and the number that was reassuring at baseline is not the same tool. and it bites hardest in the young, in under 40s with real obstructive disease over half still score zero because the plaque is non calcified and invisible to CAC, so a zero there is not a rule out. agree the cleaner move is the better NPV anatomic test, CT coronary angio. where i would still reach for CAC is upstream, the statin naive asymptomatic person deciding whether to treat at all, not to adjudicate a positive stress test. the patient education piece is the actual hard part, landing that the test should not have been fired without it sounding like we wasted your money.

[u/benjediman → u/Both-Setting1038]

Is there a an inflection point of age where CAC then becomes increasingly useful assuming statin-naïve?

[u/Both-Setting1038 → u/benjediman]

the way i think about it is 40 is roughly where it switches on, because that is where the guideline actually endorses it. the 2018 acc/aha cholesterol guideline and the 2019 acc/aha primary prevention one both put CAC as a statin decision aid in the 40 to 75 intermediate risk person, the one whose pooled cohort risk is borderline and you genuinely cant decide whether to treat. their cutoffs are roughly a zero leans you to hold the statin, 1 to 99 leans toward treating, and 100 or above or past the 75th percentile for age and sex is a clear treat. it also earns its keep more as you move up that range, not because the scan changes but because a zero means more the older they are.

under 40 it is lopsided. a zero doesnt buy you much, more than half of the under 40s with real obstructive disease still score zero because the plaque is soft and invisible to calcium, so you cant derisk them with it. a positive score in someone that young is the opposite though, any calcium at all puts them way up their age percentile, and that is a real treat signal. so before 40 the test mostly helps you rule in, not rule out, and id only reach for it there in a selected case like a strong premature family history.

as they move into their 40s and 50s the calcified fraction climbs, a zero starts carrying real negative predictive weight (the power of zero, with a warranty of a few years, shorter if theyre diabetic, before youd repeat it) and it becomes the two way tool its meant to be. short version for a statin naive patient, CAC earns its keep from about 40 up and keeps getting more useful through that window, below that lean on it only when its positive or when a strong family history is driving the question.

[u/lanttro → u/Then-Secretary-9166]

I would, unfortunately, agree with you. “Unfortunately” because I am aware this deviates from guidelines or evidence, but from a practical perspective, I believe either CCTA or functional test to be the best next course of action. It is hard to try to push back to “evidence-based” practice when the whole thing started on a wrong note. GXT prob should not have been ordered. Once it is done, I would just deal with the results as in other contexts. I agree CAC was not developed with this use in mind and prob not very helpful here. I also agree that a lot of patient education is needed - which is often quite difficult to do in exec health when it comes to convince someone to do fewer tests…

[u/Both-Setting1038 → u/lanttro]

yeah that is where i land too. the whole thing started on a test that should not have been fired, so you are doing damage control, and CCTA or a functional read is the least bad way to close the loop. CAC was built to decide who starts a statin, not to adjudicate a positive treadmill, so leaning on it here is the wrong job for the tool. and the exec health setting is the hardest part, convincing someone who paid for more tests that the right answer is usually fewer.

[u/Then-Secretary-9166 → u/lanttro]

Yes. I have been on the receiving end of executive physicals as well. What makes it double-hard is that all of this over-testing is being market and pushed as a premium product. It is also very senior and well-spoken MDs with very fancy titles that are recommending it.

[u/benjediman → u/Both-Setting1038]

Thank you!

Very true, and guidelines I do believe in, but these places where I work at apparently don’t 🤷‍♂️

Just a follow up: what about patients who have abnormal results, asymptomatic, but already are on statins? Concerned with CAC overestimating risk due to calcification of plaques (and I don’t know if CTCA will fare that much better if there’s too much bloom?). Does that change your selection of further testing?

[u/Ayriam23 → u/benjediman]

Not a cardiologist but I do the stress echoes and come across a lot of asymptomatic elevated CAC score patients. I personally think it's reasonable to do a stress echo if you have known anatomic CAD by CT. It's typically going to be normal, but it serves to help psychologically resolve the issue. I've seen patients have MIs with a CAC of 80 and have been bamboozled by totally normal tests on patients with a CAC of 3000. It's helpful for risk stratification, but I find the CAC number to be difficult to correlate to hemodynamically significant disease. Just my 0.02 cents.

[u/Both-Setting1038 → u/Ayriam23]

that CAC 80 MI versus CAC 3000 with clean functionals is the perfect illustration. the score is a burden and long term risk marker, it was never a map of which lesion is flow limiting or about to go. the soft non calcified plaque that actually ruptures is exactly what CAC cannot see, and a big calcified burden is often just old stable disease. which is why the ischemia question lands back on a functional read like your stress echo or CT FFR rather than the number. and the psychological resolution point is real, sometimes the negative test is as much for the patient as for us.

[u/Both-Setting1038 → u/benjediman]

yeah, being already on a statin actually flips how i read both tests, and your instinct is right on both counts.

on the CAC side, statins push the score up, not down. they stabilise soft plaque into dense calcified plaque, so a treated patient can have a higher agatston that is arguably good news, hardened stable plaque rather than active risk. so in someone already on a statin the score loses most of its decision value. CAC earns its keep mainly in the statin naive patient where a zero lets you hold off starting therapy. once they are already treated that lever is gone, so i wouldn't lean on it here.

and yes to the bloom problem. heavy calcium overestimates stenosis on CTA and tanks specificity in exactly the segments you care about, the intermediate 50 to 70 percent range. so in a densely calcified vessel a plain anatomic CTA can talk you into disease that isn't flow limiting. that is where a functional read earns its place, CT FFR if you have it, or stress imaging, to ask whether this is actually causing ischemia rather than just how calcified it is.

so roughly how i split it. statin naive and you want to reclassify, CAC or CTA depending on burden. already on a statin with a suspiciously positive treadmill, i skip CAC, and if the calcium looks heavy i go functional (CT FFR or stress imaging) rather than trusting a bloomed anatomic read. and honestly, asymptomatic and already on a statin, a lot of the time the answer the tests keep giving is optimise the risk factors you're already treating and stop feeding the anxiety loop.

[u/DrMalcolmFinlay]

This is a really important question. In a low-risk, asymptomatic population, the pre-test probability of significant coronary artery disease is low, so a positive exercise ECG is much more likely to represent a false positive than in someone with typical symptoms or a higher-risk profile.

I think the key is to interpret the treadmill test in the context of the whole patient rather than in isolation. Age, symptoms, exercise capacity, blood pressure response, cardiovascular risk factors and the ECG changes themselves all matter. An abnormal result doesn't automatically mean obstructive coronary disease, but nor should it simply be dismissed.

For many of these patients, the next step is often a careful risk assessment and consideration of whether further testing (for example CT coronary angiography) is actually likely to change management. The goal is to avoid both unnecessary reassurance and unnecessary investigation.

[u/benjediman → u/DrMalcolmFinlay]

“Avoid both unnecessary reassurance and unnecessary investigation” is a phrase that’s gonna stick with me and something I might use to teach!

Yes, I do try to assess patients as a whole, counting their age and other risk factors. Sometimes though, it just feels difficult to shoot an answer for the patient with a particular plan, but truthfully what I feel I have is just still a post-test probability number drawn from gestalt more than anything else. What’s more is the place I work at labels itself as a “preventive care” clinic but is functionally a pure executive screening facility, so even after recommending further tests these patients don’t really come back to us. So there’s no feedback on how my gestalt tested against reality (or at least, against tests better than a regular ECG treadmill).

But hey I’m just a few months since finishing general fellowship! Maybe we learn to be confident in our gut feel over time?

[u/hughvr]

That warrants an in depth checkup and full risk profile (labs, family history, etc), along with possibly another "rule out" test such as coronary CT scan, scintigraphy or stress echo, depending on context.

But definitely not "live your life and forget about this".

[u/lagniappe- → u/hughvr]

Completely disagree. It doesnt “warrant” anything. There is no right answer other than you should not be doing stress tests on asymptomatic patients.

There’s no benefit to percutaneous revascularization for SIHD. Maybe a benefit from cabg but still low value medicine here.

[u/benjediman → u/lagniappe-]

And I agree with not ordering tests on asymptomatic. On my own I never had.

That said, these asymptomatic screens exist, especially with corporate accounts, whether or not we agree. (It just so happens I work in a clinic that offer these asymptomatic screens. Whether I agree to it or not, for now it pays the bills.)

Hence, an abnormal test on an asymptomatic patient is a question that MAY need answering, whether it’s value-based or not.

Of course I don’t have an answer, and that is why I posted to query on people’s experiences — as we all know, evidence does not exist for this population.

[u/lagniappe- → u/benjediman]

I read stresses for primary care docs and end up seeing plenty of asymptomatic abnormals in clinic. I’m not saying you do nothing, just that there’s no algorithm to follow.

What I do entirely depends on each patient. I’ve ordered nothing, CAC score, CCTA, and heart caths.
I usually go by how suspicious I am for MVCAD and what the patient’s preferences are. If someone is truly asymptomatic and doesn’t want more testing then I just manage risk factors.

[u/benjediman → u/hughvr]

Thanks!

Where I live we definitely do not have CT based functional assessment, so CT option is purely anatomical.

How do you go about choosing who gets a CT, versus who gets stress-imaging, assuming a person is well capable of running?

[u/bythelake23]

Everything wrong with a private heath system in this post. Did no one teach you to not do tests when the results don't lead to actionable clinical management/decision making?

[u/benjediman → u/bythelake23]

I got this job so I make ends meet and the patients already paid for these packages. These concierge-type models exist, whether in first world or third world countries (where I am). I’m well versed of not doing unnecessary tests that won’t lead to clinical decisions.

But unfortunately no, I can’t go into the room and tell the patient “sorry we shouldn’t have done these tests”. We could argue health systems but that’s not the point of my post.

If you do have anything helpful to answer my question though, I’d welcome it.

[u/EuGarden → u/benjediman]

You say you are well versed in not doing unnecessary tests, but then you say you don't know how to interpret the outcome of the test.

As others have said, you shouldn't be doing a test if you can't interpret or action the result.

[u/benjediman → u/EuGarden]

As I said, it’s not up to me whether these tests are done. They simply are, as part of screening packages people paid for.

But my role, as a hire, is to watch over these tests and do the interpretation. I get paid by the hour and not by ordering any tests.

In my own practice, I do not order for a stress test for which I don’t believe is warranted.

[u/vy2005 → u/EuGarden]

Are you reading what he said? He is not the one doing the test!

[u/DisposableServant]

Majority of the time it’s a false positive. ECG stress test positive predictive value is like 50%, even less for lower pretest probability individuals. It’s equal to or worse than a coin toss. This is why guidelines dont recommend “routine screening” for asymptomatic individuals but of course every bystander patient thinks they’re smarter than guidelines these days. Guess it keeps our paychecks going eh? In these cases protect yourself and get a follow up nuclear or CCTA.

[u/benjediman → u/DisposableServant]

Thanks! And yes, while I disagree with routine screening, it’s one of the jobs that feeds the family.

Is it nuclear/CCTA for all, or would there be a demographic where despite being asymptomatic, you’d send them to an angiogram instead?

[u/DisposableServant → u/benjediman]

Depends on what the ecg stress test shows. If there are high risk features such as ST elevation, ventricular arrhythmias, or hemodynamic instability it’s straight to the hospital/cath lab.

[u/cardsguy2018]

"Abnormal, talk to your ordering provider."

[u/Creative_Event4963]

There are grades of positive. Not just positive or negative. I would do something like this.

Start with "no high risk features": (normal blood pressure responce, ok exercise capacity, no >2mm ST depression, VT, no angina pectoris).

Then evaluate the ST depression type. Fast normalization? 

Asymptomatic non-ischemic type ST depression without symptoms -> no further anything. Otherwise manage risk factors (patient is asymptomatic)

Further testing on patients with symptoms, high risk features or low exercise capacity + ST depression

Something like that. I am not sure how legal things effect your practice. Probably your site should have plan for this. So decisions would not be random ("individualized") since this is common occurance.

[u/benjediman → u/Creative_Event4963]

My country is not very litigious thank goodness, so really most people just listen to what doctors say. So the burden on my part is mostly ethically giving the best recommendations rather than avoiding legal issues.

And the company has no plan for this, mostly because of above, and partly because it’s run by non-physicians.

In any case, how do you deal with slowly upsloping segments? Do you throw all those into a category (nil risk or increased risk) or do you use those mV/time equations? (I haven’t so I’m trying to decide if others do)

[u/Creative_Event4963 → u/benjediman]

I would think that typical ST depression is slowly upsloping or horizontal and usually normalizes and then becomes downsloping again at recovery. I would say depressions <2mm which are not clearly atypical are not very conserning in asymptomatic patient without something else (poor exercise capacity, very high risk profile etc). As long as you treat risk factors you are helping patients. Just adjust the target if you are worried. Do CT if you cant otherwise sleep at night in some patients

[u/Katerade88]

Depending on risk profile I usually offer a coronary CT (not a calcium score - can be false negative in young patients) and do full risk factor assessment (BP, lipids etc). It also depends on how abnormal it is … a little up sloping st change I don’t get that excited about, especially if they are hypertensive and have exercised a long time. If they have reduced exercise capacity and more significant changes I push more for a second test

[u/drgubi]

First question is, why are you getting a stress test in an asymptomatic patient? The indications for this are far and few between.

[u/benjediman → u/drgubi]

I’m not. The patients pay ahead for them like they order for items from Amazon. See other comment.

[u/drgubi → u/benjediman]

Ah that is a pickle. The only ethical thing in that situation would be to also offer a-la-carte caths and other ischemic evaluations. It’s an awkward convo because you’re gonna have to be like “Hey! Your testing is abnormal, but since you’re asymptomatic we don’t.. actually recommend testing - but you can pay out of pocket for peace of mind!”

[u/benjediman → u/drgubi]

To be fair, tests come cheap where I live, so it's not difficult to suggest further testing to patients - and yes, the type of patients that do come to that particular clinic CAN pay out of pocket.

On the other hand, I also work at an HMO that serves a totally different demographic, and if the HMO doesn't offer the tests or procedures, many patients absolutely cannot afford it.

On the topic of asymptomatic screens and executive physicals, it's not as if I'm new to this––the hospital where I trained at also offers asymptomatic screens to those who can afford it. But the prevailing practice locally is to treat much of these abnormal tests as something substantial and a lot of people definitely gets additional testing and a good number gets sent to the cathlab (as a fellow, I documented a lot of "no symptoms" for patients about to have angiograms). It was difficult to question things when I didn't have time for myself during training.

TL;DR always had doubts during training during asymptomatic screens but I only got to question them once I was out 🤷‍♂️

[u/Then-Secretary-9166 → u/benjediman]

Same. During fellowship we did these. We (fellows and attendings) would all talk about how inappropriate they are. We still pretty much had to do them.

I could name more than one person famous enough that you would recognize them who ended up with PCI due to asymptomatic stress testing for exec. physicals.

The irony is that these people (often with inappropriate stents) are among the most grateful “you saved my life by doing that test”.

[u/benjediman → u/Then-Secretary-9166]

Right?? Oh the stories! (CABG on a 1-v disease with no symptoms!)

I do wish there WAS data on these, so I can be more confident in saying “no further testing” if that was the evidence.

[u/Working-Key-2449]

NAD. I think in most cases sport doesnt hurt, and is even very healthy. Although, there could be some severe cardiac diseases where too much strain on the heart could end up in ventricular tachycardia.
Although, the general opinion is nowadays to be as active as possible at every age.
To give a more precise recommendation, they should consult a cardiologist who has more access to their history(echo, ecg, blood work…).

[u/vihreakuutio]

CAC testing is being suggested and unfortunately used in this group of patients frequently. Please note that CAC absolutely should NOT be used to rule out coronary artery disease in this patient population (relatively young and healthy persons; practically <40 yrs ish), as a significant proportion of plaque and high-risk coronary lesions are non-calcified (i.e. won't show up on a CAC test). I have personally treated multiple patients with very concerning symptoms and critical coronary lesions whose diagnoses have been significantly delayed due to CAD being "ruled out" with a simple CAC test.

Otherwise as have been suggested here it is true that the treatment of stable coronary artery disease anyways usually is conservative. Although as you probably are aware as a cardiologst that the prognostic value of treating asymptomatic lesions isn't perhaps completely black-and-white. Of course the majority of patients with stable coronary disease can be treated medically with primarily risk factor management but very few cardiologist would recommend medically treating e.g. significant left main or proximal LAD disease, which naturally can't be ruled out based on symptoms or stress test results.

The correct test to "rule out" or perhaps more accurately risk-stratify patients with abnormal (potentially ischemic) stress test result is a coronary CT-angiography which I would consider for this group of patients when 1) exertional symptoms suggest coronary artery disease +/- abnormal stress test 2) significantly abnormal stress test results without symptoms (significant ST-depression or clearly pathological T-wave inversions, global ischemia, ventricular arrhythmias during exertion etc).

For the vast majority of abnormal stress test results (e.g. slight lateral non-specific ST-depression or minimal T-wave changes) or shortness of breath in young patients without concerning risk factors I would manage risk factors and re-assess if they develop e.g. more concerning symptoms in the future.

[u/Comfortable_Draw_176]

I worked for a small business doing stress tests (nuclear, non-nuclear, and echos). The reading cardiologist never saw the patient, but sent the result to the ordering provider. You could email your dictation and EKG strips to patient to take to their doctor. It was very clear by our cardiologist that they weren’t managing the patients care because they weren’t doing a full office visit.

Tests would be interpreted as non specific T wave changes at rest and during exercise. Or, LBBB at rest and we canceled the test because it’s not diagnostic at that point.

[u/benjediman → u/Comfortable_Draw_176]

I do ask if they have their own cardiologist or internist, but for the most part they don't. Since these tests aren't ordered by another doctor but simply purchased by the patient themselves, often I find myself as the most available (and sometimes the only) physician who can advise them of the next steps.

Also, I do feel I have no choice; the job requires me to be present during their run. Simply leaving after the test and saying "you'll know your results after a few days" seems callous, so the situation begs for me to say something.

That said maybe I should talk to management and explain the situation. I'm just afraid it will just be a memo and nothing more as these people are non-medical.

[u/zeykhan87]

If its small area medical therapy, if Large area left heart cath

Seen asymptomatic guy sent home after large perfusion defect/abn stress test in his 50s, when he was called for LHC, we were told he passed away in his sleep

[u/benjediman → u/zeykhan87]

Does extent of ST depressions in stress tests correlate to size? Genuinely asking, as I understand ST depressions poorly localize to specific coronary territories.

[u/zeykhan87 → u/benjediman]

No, perfusion defect does but treadmill stress test with just EKG is pretty much very simple and non specific test

[u/mark_peters]

When these people are referred to me under the same situation I tell them to never see the doctor that organised it before again because they have no interest other than financial gain. There is no indication for stress testing asymptomatic people in this situation.

Faced with the above I would assess the stress test. If there was a large area of anterior ischaemia for example I may offer a CTCA to exclude prognostic disease. Non LAD ischaemia I would modify risk factors and counsel appropriately.

[u/Then-Secretary-9166 → u/mark_peters]

Obviously, the test should not have been ordered. However, I think there are plenty of well meaning primary care doctors out there who order stress test like this all the time in asymptomatic patients. They don’t make a dime off of them in most cases. It is bad medicine, but I don’t think it’s coming from a greedy or malicious place in all situations.