Every medical test has false negatives because neither humans nor machines operate with 100% accuracy. However you are in very serious jeopardy whenever you receive a false negative result on a Cardiolite stress tests. That's because of an astonishing fact about cardiologists in the U.S: they are willing to accept the fact that, even in they could administer and interpret cardiolite or thallium stress tests with 0% errors, that 2%-3% of their patients whose coronary arteries receive the most desirable rating of "normal" actually have coronary arteries in the LEAST desirable and most severely diseased state, known as "3-vessel disease" 3-vessel disease means that you have not just one seriously blocked coronary artery, not just two seriously blocked coronary arteries but rather have 3 or more coronary arteries which are perilously close to becoming totally blocked and causing a myocardial infarction.
If you respond "That can't be!", I'm here to tell you from personal experience that it can be true, and is true. 13 months after being given a "normal" test result after I had undergone a thallium/Cardiolite-type Nuclear stress scan test, I awoke to find myself lying in a bed in the ICU of a major Heart Center. A nurse was standing there and I asked why I was there. She responded, "Honey, you collapsed 10 days ago and had to undergo emergency 'high-risk' quintuple coronary artery bypass surgery in order to survive." "Triple bypass?" I asked incredulously. "No, not triple. Quintuple. You had 5 coronary arteries that needed bypassing."
I asked my cardiologist how I could have needed a quintuple bypass when my test said my arteries were normal. He shrugged and said, "Reading the results of a nuclear stress scan of your heart mainly entails comparing how the nuclear material settles into various different areas of your heart. We can tell which artery is bad by comparing the area it feeds to the other areas. But if all your arteries are bad, then the heart tissue all looks the same, just like the tissue all looks the same if your arteries are all normal. It's almost impossible to distinguish "all-bad" from "all normal".
Ridiculous, laughable primitive. But absolutely true. If your doctor says all your arteries are normal, he really means that they're either all-good or all-bad.
Sorry, but most of what you say here is just not true. It all depends on the patients symptoms. I spend many hours each week volunteering with a cardiac care center and get to talk to many cardiologists. If a patient has a normal nuclear stress test and symptoms are present, they always proceed to an angiogram to be sure. That is the normal protocol as outlined by the NIH. You had your issues 13 months after a clean stress tests, plenty of time for things to change. CAD is a dynamic process with periods of slow and aggressive progression. Had you complained about symptoms after your test you would have had a cath and more would have been learned. It still may not have prevented you problems as arteries can go from 50% to 90% very quickly, or over a long period of time.
The actual numbers on a Nuclear Stress test is an overall accuracy of 85%, with a sensitivity of 80% meaning finding CAD when there is none and 97% specificity, finding no heart disease when there is none. That does leave room for some fall through the system, but overall pretty accurate and much less invasive than an angiogram.
Erijon, while you started out strong in saying that most of what I said was wrong, your ultimate conclusion was identical to mine, namely, that about 1 out of every 30 people who are told that their coronary arteries are uniformly normal actually have coronary arteries that are uniformly diseased in the worst possible way. Let's be clear here - Nuclear cardiology centers may have the look of a small mission control or the deck of a modern submarine, most of it is really for show, not accuracy.. In the end, when it comes to actually reaching a determination as to whether or not you have diseased coronary arteries, the nuclear cardiologist lines up images of your heart which have not been placed under stress, then compares them against images after yout heart was stressed. If he or she sees uniformity of perfusion among the full set, the cardiologist will determine that your coronary arteries are normal and will tell you so without telling you that there is simply no way to tell the difference between a patient with no blocked arteries and a patient with all of his coronary arteries seberely occluded and diseased.
Ask your cardiologist directly about this and they will readily admit that 30 years ago when the nuclear stress test was state of the art, that it was simply accepted that the images of the patients with 3-vessel diseease would likely seem as clearly normal as those that are actually normal. But that was during a time period when little could be done to help such badly diseased patients anyway. The difference between then and now is that there is plenty that can now be done to save those with the most severe coronary artery disease. In essence, such patients are no longer throwaways. Yet cardiologists continue to treat them that way.,.
Yes you are both correct. However, it doesn't even have to be triple vessel disease for the scan to be misleading. What I believe confuses the issue are collateral vessel formation. If collateral vessels open up, to bypass blockages, these can be inadequate for the heart under stress, giving angina symptoms. Those symptoms can also be quite severe. In the nuclear scan, it can appear that a substantial amount of blood is reaching the heart muscle. I think there is a fine line between 'what looks good' and 'what feels good'. If the heart muscle isn't getting quite enough blood for exertion, and exerts Angina, the scan will still look amazingly good. This is why my Cardiologist always does an Angiogram first. He then has a nuclear scan done to actually confirm necrosis. It's back to collaterals again. Most collaterals are too small to be seen on an angiogram, and if wall motion is abnormal, or the wall is moving so slightly that you can't detect the motion, you could assume necrosis. A nuclear perfusion scan will confirm or deny this. Obviously there is no point in revascularizing dead heart muscle.
In 2007 I had a stent to my LCx because of agonising angina symptoms. During the Angioplasty my LAD was seen to be 100% blocked at the top, and the RCA was totally blocked halfway down. My Cardiologist felt sure that I had necrosis, and a lot of it on the left side because the motion was totally abnormal. Of course at the age of 46, I was devastated to hear this and was sent for a Nuclear perfusion scan. I had to wait two weeks to hear the results. There was no muscle death. Collaterals had obviously opened up but were still inadequate due to angina upon exertion. I had a triple bypass, which failed after 3 months. During that three months I felt great. I was then told nothing could be done, stenting was impossible because the plaque was way too hard. A top Cardiologist in Imperial College London heard of my case and said he could open the LAD. He was so sure of himself and said there were no risks as far as he was concerned. Yet 12 Cardiologists across various hospitals had told me that this procedure was impossible because there was a 1 in 10 chance I would be killed. It shows how desperate I was, I trusted this man and went for it. He slowly chipped away at the plaque and grabbed any loosened chunks for removal. Finally, the blockage broke through and the LAD swelled up to a huge size. The heart monitor ECG trace went nuts for a few seconds and then settled. I had a totally different trace to what I had before. I could feel the throat discomfort was gone and I was breathing 12 times a minute instead of 16-20. The results were that quick. He stented the area and I thought that was it. He then decided to clean the rest of the vessel because it was coated with plaque. I had 5 of the longest stents available put into that vessel. Before he stented with the drug eluting type, he used a drug eluting balloon to expand the vessel. This delivers lots of scar inhibiting drugs to the artery wall. Today (3 years later) the vessel is still wide open. The triple bypass I had, involved the Lima from the chest and 2 veins. The Lima was blocked at the entry into my LAD by Plaque. When the LAD was cleared, this vessel was able to get blood into my LAD also. So now, my LAD has the normal feed from the top, plus a feed into the distal through the Lima. I questioned during the procedure if the Lima should be blocked off. I imagined blood from 2 directions going through a single vessel and affecting flow rate etc. He said the pressure in the artery was great, and was gushing through the diagonals/arterioles and capillaries. So it's best to leave it alone.
If my nuclear scan was done first, I truly believe that I wouldn't be here today. The results looked remarkable and even my Cardiologist said he would have taken the images as those from an athlete, and sent me home.
Of course here (in the States, I don't know about G.B.) SOP is: "We don't do an Angiogram unless you have blockages exceeding 70%" How do they know? Because they are guessing based on the result of your Echocardiagram/Thallium Stress Test. With no symptoms I think that is a reasonable decision since an Angiogram is still an invasive procedure. I had no chest pain at the time, but shortness of breath definitely and that darn Calcium Score of 1242.
What it really boils down to is, I think, would be in form of a question to "bb659": what type of chest pains do you actually have? If it is unstable Angina, I wouldn't care what the stress test says and would get an Angiogram anyway.
I am sorry, I thought somebody neede advice here. Then I looked at the date. This was 3 years ago, where is the delete button?