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1/15 #MedTwitter: You're admitting a 64YO male with ESRD on HD for hyperkalemia after missing dialysis. A troponin was checked & returned at 0.78 (nl<0.055 ng/mL), similar to his baseline. He is w/osymptoms and EKG is w/o dynamic changes. What would you call this #tropbump?
2/15 Have you ever been taught to think about troponin as being cardiac vs. non-cardiac in origin? Though this may be a nice framework, itโs simply untrue: if youโre measuring cardiac troponin I (cTnI), it is expressed only on myocardium(not skeletal muscle, unlike troponin T).
3/15 The lexicon to describe troponins is confusing!
"๐๐ณ๐ฐ๐ฑ๐ฐ๐ฏ๐ช๐ฏ๐ฆ๐ฎ๐ช๐ข" is frequently used but is not very helpful. It is NOT a diagnosis or etiology, and should probably be abandoned as a term altogether.
"๐๐ณ๐ฐ๐ฑ๐ฐ๐ฏ๐ช๐ฏ๐ฆ๐ฎ๐ช๐ข" is frequently used but is not very helpful. It is NOT a diagnosis or etiology, and should probably be abandoned as a term altogether.
4/15 Hereโs a framework for thinking about #tropbumps.
Ask: are there signs of ischemia? If so, you may be facing an โ๐ ๐โ: ๐ฎ๐บ๐ฐ๐ค๐ข๐ณ๐ฅ๐ช๐ข๐ญ ๐ช๐ฏ๐ง๐ข๐ณ๐ค๐ต๐ช๐ฐ๐ฏ, which can be due to plaque rupture/thrombus (Type 1) or myocardial oxygen demand/supply mismatch (Type 2).
Ask: are there signs of ischemia? If so, you may be facing an โ๐ ๐โ: ๐ฎ๐บ๐ฐ๐ค๐ข๐ณ๐ฅ๐ช๐ข๐ญ ๐ช๐ฏ๐ง๐ข๐ณ๐ค๐ต๐ช๐ฐ๐ฏ, which can be due to plaque rupture/thrombus (Type 1) or myocardial oxygen demand/supply mismatch (Type 2).
5/15 With type 2 MIs, classically, ๐น๐ผ๐ผ๐ธ ๐ณ๐ผ๐ฟ ๐๐ถ๐๐ฎ๐น ๐๐ถ๐ด๐ป ๐ฑ๐ถ๐๐๐๐ฟ๐ฏ๐ฎ๐ป๐ฐ๐ฒ๐.
Type 2 MIs can occur in the presence of fixed atherosclerosis, but coronary artherothrombosis is not the underlying cause for troponin elevation.
Type 2 MIs can occur in the presence of fixed atherosclerosis, but coronary artherothrombosis is not the underlying cause for troponin elevation.
6/15 And then thereโs ๐ ๐๐ก๐ข๐๐.
๐๐ฉ๐ข๐ต ๐ต๐ฉ๐ฆ ๐ฉ๐ฆ๐ค๐ฌ ๐ช๐ด ๐๐๐๐๐๐?
๐๐ฉ๐ข๐ต ๐ต๐ฉ๐ฆ ๐ฉ๐ฆ๐ค๐ฌ ๐ช๐ด ๐๐๐๐๐๐?
7/15 ๐๐บ๐ฐ๐ค๐ข๐ณ๐ฅ๐ช๐ข๐ญ ๐ช๐ฏ๐ง๐ข๐ณ๐ค๐ต๐ช๐ฐ๐ฏ ๐ธ๐ช๐ต๐ฉ ๐ฏ๐ฐ ๐ฐ๐ฃ๐ด๐ต๐ณ๐ถ๐ค๐ต๐ช๐ท๐ฆ ๐ค๐ฐ๐ณ๐ฐ๐ฏ๐ข๐ณ๐บ ๐ข๐ต๐ฉ๐ฆ๐ณ๐ฐ๐ด๐ค๐ญ๐ฆ๐ณ๐ฐ๐ด๐ช๐ด = MINOCA, and accounts for 6% of MIs. It is much more common in women than men.
8/15 Mechanisms of MINOCA vary, but patients typically present with symptoms of acute MI โ which can even include a STEMI! โ but are found to have non-obstructive or no CAD and all other causes of myocardial injury are ruled out.
9/15 If your patient has no signs, symptoms, or findings of myocardial ischemia, you are dealing with ๐บ๐๐ผ๐ฐ๐ฎ๐ฟ๐ฑ๐ถ๐ฎ๐น ๐ถ๐ป๐ท๐๐ฟ๐ w/o ischemia, which comes in 2 flavors: acute or chronic depending on the serial troponin variability.
10/15 In the case of our patient, he most likely has ๐ค๐ฉ๐ณ๐ฐ๐ฏ๐ช๐ค ๐ฎ๐บ๐ฐ๐ค๐ข๐ณ๐ฅ๐ช๐ข๐ญ ๐ช๐ฏ๐ซ๐ถ๐ณ๐บ without ischemia.
You may have learned that high troponins in ESRD is from decreased clearance. If that were true, troponins should change pre vs. post dialysis, right?
You may have learned that high troponins in ESRD is from decreased clearance. If that were true, troponins should change pre vs. post dialysis, right?
11/15 The data is mixed here. Some studies show no troponin change pre/post dialysis; others show slight decrease. https://pubmed.ncbi.nlm.nih.gov/10085490/
12/15 
clearance alone doesn't explain the whole picture of asymptomatic troponin elevation in ESRD.
Myocardial microinjury from osmolarity/ion fluxes, preload/afterload changes, calcium deposition are at play as well.
clearance alone doesn't explain the whole picture of asymptomatic troponin elevation in ESRD. Myocardial microinjury from osmolarity/ion fluxes, preload/afterload changes, calcium deposition are at play as well.
13/15 Ever wonder why patients with stroke can have high troponins? Is it cardioembolic? Or catecholamine mediated?
๐๐๐๐๐๐ found that patients with ischemic strokes were less likely to have obstructive CAD compared to matched NSTEMI patients. https://pubmed.ncbi.nlm.nih.gov/26933082
๐๐๐๐๐๐ found that patients with ischemic strokes were less likely to have obstructive CAD compared to matched NSTEMI patients. https://pubmed.ncbi.nlm.nih.gov/26933082
14/15 The study hypothesized catecholamine-mediated injury, but was small in size.
More recent studies have suggested possible cardioembolic etiologies (ie. MINOCA). https://pubmed.ncbi.nlm.nih.gov/29167390
injury, but was small in size. More recent studies have suggested possible cardioembolic etiologies (ie. MINOCA). https://pubmed.ncbi.nlm.nih.gov/29167390
15/15
๐ง๐ฎ๐ธ๐ฒ๐ฎ๐๐ฎ๐๐:
1.Abandon the term โtroponinemiaโ.
2.Not all troponin elevations are โMIโs. The term MI should be reserved only for ischemic causes.
3.When there are no findings of ischemia, you are dealing with myocardial injury.
๐ง๐ฎ๐ธ๐ฒ๐ฎ๐๐ฎ๐๐:
1.Abandon the term โtroponinemiaโ.
2.Not all troponin elevations are โMIโs. The term MI should be reserved only for ischemic causes.
3.When there are no findings of ischemia, you are dealing with myocardial injury.
