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Talk:Myocardial perfusion imaging

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My edit discussing what has been a fatal flaw (literally) built into myocardial perfusion imaging has been one of the 'dirty little secrets' of cardiac medicine which, day in day out, places at risk the very most ill patients with CAD by categorizing their test results as negative when in fact they could as easily be read as positive. The problem arises because proper perfusion of various areas of the mycardium is determined by comparing the results for each part with one another. Thus if one of the areas 'pictured' by the SPECT camera has a different appearance from the rest of the areas, it is an obvious indication that the differing area has a perusion level which is less than those of the other areas pictured. In such instances, a postive result is determined and the patient is referred for additional testing and possible interventional action.

The problem arises when all the areas depicted in images seem similar to each other. The great majority of the time this is an indication that there are no occluded coronary arteries leading to the heart and results of the test are determined to be neagative for arterial occlusion. But out of the population of patients who tend to be referred fpr myocardial nuclear perfusion, a still sizeable number of patients, between 2-3%, will be suffering from occlusion to all of their major coronary arteries. Unfortunately, the images which are compared by nuclear cardiologists to each other when a patients has all of their major coronary arteries blocked will be similar to each other in the same way that the images are similar when no arteries are blocked.

At some point during the development of myocardial nuclear perfusion testing, it was determined that ALL nuclear scan test results where the images all resemble each other should be identified as negative results despite the fact that physicians have known that in so doing they will be wrongly and consistently be diagnosing those with all arteries occluded - i.e. the sickest of patients - incorrectly as negative when in fact they are showing the most positive of test results.

I had 3 vessel- disease in 2005 when I was administered a myocardial nuclear perfusion test, but was advised after the test that my results had been negative for coronary artery disease. 17 months later, I was undergoing on an emergency basis quintuple coronary artery bypass surgery after surviving cardiogenic shock, MODS and other conditions related to my heart's inability to receive enough oxygen through my coronary arteries. My surgery had been delayed unncessarily for 7 days because my doctors had obtained access to the incorrectly negative results of my myocardial perfusion test and assumed that something other than blocked coronary arteries were causing my heart difficulties. I nearly died 3 times in a circumstance where, had I received a proper reading of my perfusion scan results I could have been scheduled for routine coronary bypass surgery and avoided the complications I continue to face, particularly significant and permanent brain damage. QuintBy (talk) 19:05, 29 September 2012 (UTC)[reply]

With due respect to QuintBy's personal circumstance and the need to point out and describe limitations of a technique, I am calling for a reorganization of the page to keep proper ordering of the sections on the technology itself, its current clinical uses, and its limitations, complete with salient references. — Preceding unsigned comment added by Sprevrha (talkcontribs) 13:39, 9 January 2013 (UTC)[reply]

Radiation dose

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There is an uncited line stating that people criticise NM perfusion imaging due to radiation exposure; it further states that there is less exposure than in angiography or CT angiogaphy.

Myocardial perfusion scans account for 20% of US population radiation exposure, and 25 per 10000 scans (at age 50) for combined isotope scan like that pictured in the article.

Myocardial Perfusion Scans Projected Population Cancer Risks From Current Levels of Use in the United States Amy Berrington de Gonzalez, DPhil; Kwang-Pyo Kim, PhD; Rebecca Smith-Bindman, MD; Dorothea McAreavey, MD Circulation.

2010; 122: 2403-2410 

Published online before print November 22, 2010, doi: 10.1161/​

Cancer risk is four times higher if performed in a 20 year old Can we change this? — Preceding unsigned comment added by 113.197.8.190 (talk) 01:52, 27 April 2013 (UTC)[reply]