Heart Exercise Stress Test - Help Please

The odds are high of what?

Right. So they stopped the test due to an ST- segment shift on the monitor and not because she was physically unable to complete it.
Again, a good prognostic sign.

Itā€™s the ST segment shift that could be a false positive that the cardiologist will sort out.

Itā€™s tricky in females, especially young females, because they manifest ischemic heart disease differently than men. They often have atypical symptoms and false positives on ETT.

I know itā€™s difficult , but try to relax about this until you get more information and the complete picture.

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The chances that you will find multiple videos on the exact topic you are concerned about are high.

Thank you for all of your advice. The situation bothers me a lot. I donā€™t want anything bad to happen to her. Thank you again.

Hereā€™s a review of those more likely to have a false positive test and youā€™ll see that your wife fits most, if not all, of the categories.

https://academic.oup.com/eurheartj/article/34/suppl_1/P3375/2861932

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Why do you even want to do a nuclear stress test? I actually would rather have the angiogram than another horrible treadmill test coupled with an injection of a radioactive isotope.

Oh, I know, the cardiologist makes more money.

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Nothing to do with money making.

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I am not a doctor, but I can read what other doctors are saying. Stress tests produce a lot of false positives and you end up getting an angiogram anyway.

My personal view is that many people, especially the elderly, have arthritis problems, bad knees, bad ankles etc. So, a stress test is very painful compared to an angiogram

ā€œOf the 150 patients with an abnormal exercise stress test, 122 (81%) ultimately had confirmatory testing that demonstrated no coronary artery disease. In other words, 81% of the abnormal tests were confirmed to be false positives.ā€

ā€œOf the 125 patients with positive stress tests, 102 had further testing. Only 33 of these follow up tests were positive, so the vast majority of positive stress tests were false positives.ā€

ā€œBottom line: Nuclear stress testing has a moderate accuracy for coronary artery disease. It is not a good enough test to rule in or rule out the disease, and it isnā€™t clear how the result of this test will be used to benefit patients.ā€

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Angiograms are not covered by our insurance. They can be quite expensive. Itā€™s time to get new insurance. Heart surgeries are covered thoughā€¦

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Having worn masks extensively during my medical training I confess that I used to roll my eyes a lot about all of the people who would bitch about having to wear them because of COVIDā€¦ ā€¦and then I had occasion to exercise (dancing) while wearing one. Sometimes things are okay, butā€¦ holy crap. When one is breathing heavy they really can fill up with water vapor and lead to some combination of hypoxia and/or hypercapnia (too much CO2). If your wife was panting because of the mask then that could absolutely lead to a false positive stress test showing ST changes that would have everything to do with poor gas exchange in her lungs and nada to do with her coronary arteries.

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I hope you are right. For now, surgical masks are required at all doctors visitsā€¦ and pretty much everything except eating or exercising outside.

Another thing to keep in mind about stress tests is that they can pick up other causes of cardiac ischemia. These arenā€™t necessarily ā€œfalse positivesā€ unless one has bought into the mistaken idea that stress tests are only meant to pick up significant CAD. Microvascular disease (particularly in someone with a history of hypertension and left ventricular hypertrophy) and/or just being fairly out of shape (with inadequate mitochondrial function to smoothly handle higher cardiac demand) can both lead to noticeable changes on an EKG when one is exercising. I consider it to be a GOOD thing that stress tests are often sensitive enough to pick up such issues, but I know not to read too much into the results. Still, unless there were profound changes on the EKG I find it a bit overkill to be recommending a coronary angiogram followup for an asymptomatic 45 year old woman. Before jumping to the multi-thousand dollar tests it makes more sense to me to consider the rest of her cardiac history: high blood pressure? Elevated LDL cholesterol/Apo(b)? Elevated Lp(a)? Is she a smoker? Does she have diabetes or other significant evidence of insulin resistance? Elevated hsCRP? High homocysteine? High uric acid? High OxLDL? LpPLA2? High urinary albumin/creatinine ratio? A significant family history of ASCVD at a young age?

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She has no family history of CAD or ASCVD. She does not smoke or drink. All of her bloodwork is OK and within acceptable levels. She has a history of low iron and low platelets. No diabetes. Normal blood pressure. Normal cholesterol. Did not test CRP, homocysteine or uric acid. Not sure what OxLDL or LpPLA2 are. Normal albumin and creatinine.

Would it make sense to do the treadmill test again to see if it was a fluke?

You can see in this write up that a regular stress test is only 65% accurate whereas a nuclear test is 95% accurate.

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I think the point Iā€™m trying to make is that even if she had a positive stress test, it doesnā€™t necessarily make sense to head straight for the cath lab (or for a CTA, if she prefers to get her radiation that way).

There was a huge trial a few years back called COURAGE that basically showed that for people with stable angina who had significant CAD, there was no mortality benefit for people to get stented vs. the ā€œoptimal medical managementā€ control arm. (The obvious exception was for people who were having an MI, for whom stenting could indeed be lifesaving therapy.) For some reason the interventional cardiologists (i.e. the ones who make the BIG bucks in the cath lab) usually donā€™t go out of their way to talk about that study; a lot of other cardiologists do.

My advice? Get the basic tests and disease processes that I mentioned covered before wandering back into stress-test territory. I only use stress tests (typically stress echocardiograms) to assess whether someoneā€™s chest pain is most likely the result of cardiac ischemia. That said, her positive stress test still needs to be taken into account - presumably it was positive for some reason. Get a home BP cuff and monitor BP regularly: it should be under 120/80 at baseline (i.e. most of the time). Make sure her fasting insulin levels are nice and low (my target is to get them under 5). My target for uric acid is similar (<= 5.5 for anybody with normal BP or under 5 for people with high BP). Get her homocysteine checked and strive to get it below 9.5 or so (or maybe lower, depending on whom you listen to.) Get a baseline Lactic Acid checked. If sheā€™s not on metformin that should probably be under 10; if itā€™s not she probably needs to be getting more Zone 2 (i.e. aerobic) exercise. Strive for regular aerobic exercise (or even sauna use) that will get her heart rate up regularly (30+ minutes 5+ days/week is one commonly accepted ā€œminimum effective doseā€). Make sure her hsCRP is checked regularly and that is stays nice and low - over 3 is Clearly Bad (and demands a statin unless thereā€™s something else treatable like an infection), between 1-3 is ā€œaverageā€ (but not necessarily good), under 1 is good, and under 0.5 is great. Look for evidence of elevated triglycerides, which often goes hand-in-hand with low HDL, and take appropriate interventions (avoid sugar, consider a low carb diet and/or metformin). Low-to-moderate-dose statins (plus ezetimibe and ubiquinol or at least CoQ10) and maybe even a PCSK9 inhibitor are things to consider when LDL cholesterol and Apolipoprotein B are high (exactly how high is a matter of controversyā€¦) particularly in the context of not-so-great hsCRP levels, elevated OxLDL, or elevated LpPLA2 levels. If she has a higher Lp(a) over about 75 or so then thatā€™s an important risk factor to know about (although weā€™re still not so good at treating that problem yetā€¦ but people are working on it.)

Good luck!

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You make some excellent points and I also wouldnā€™t go straight to the cath lab at this point for sure, but I would find out if the ETT was just a false positive with the nuclear ETT or echo . If it was a false positive then she wouldnā€™t have to go through all of the other tests and lifestyle changes necessarily.

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To each their own. ASCVD is still the #1 cause of death in this country (thatā€™s the USA for me). I donā€™t much care if I have a high-risk patient and Iā€™m helping to prevent a fatal heart attack in 1 year vs. identifying problems in a ā€œstandard riskā€ patient and helping to prevent the fatal heart attack in 10-30 years. Itā€™s true I donā€™t usually check OxLDL, LpPLA2, or microalbumin/creatinine levels without good cause, but the rest of those labs (and several more) are part of my standard new patient panel.

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You certainly make some great points and weā€™re not actually in disagreement.

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Sorry to be feisty. :slight_smile:

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Thinking about this for a moment, one of the things that drives my practice style away from the imaging studies and stress tests is that many of my patients donā€™t have insurance. A stress test, an angiogram or even just a CTA all cost considerably more than what I can get an extremely comprehensive lab panel for. I agree that SPECT tests are sweet, but I just canā€™t justify the cost for most people.

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