I think they might be describing angina...not sure. TXA2 is responsible for platelet aggregation,so it may be contributing to thrombosis, thus ischemia to the cardiac tissue.
Seems like I did what most of you did. I read the "symptom" as pain and went for PGE2.
Turns out if I had just read the 2008 paper Undiscovered role of endogenous thromboxane A2 in activation of cardiac sympathetic afferents during ischaemia I would have known that TXA2 MAY be a cause of MI pain. https://www.ncbi.nlm.nih.gov/pubmed?term=18483073
There are also theories that the pain is from adenosine/bradykinin/acid/ROS/5-HT which you can read about here:
I found these via the UpToDate page Angina pectoris: Chest pain caused by coronary artery obstruction which does say the mechanism is "complex and not entirely understood."
This is actually describing myocardial infarction I think, from this article: https://www.ncbi.nlm.nih.gov/pubmed/6485997
We conclude that generation of thromboxane A2 occurs during the early stages of AMI and may be an important pathophysiologic phenomenon in AMI.
Damaged endothelial cells cannot produce PGI1 and prostacyclin => platelets begin to aggregate and release TXA2
LD4 = vasoconstriction + bronchoconstriction - does it have a role in prinzmetal? I picked this thinking vasospasm due to atherosclerosis.
PGE2 = pain + fever. so i suppose because it's ischemia and not an inflammation, that's not the answer?
TXA2 = PLT aggregation --> thrombus --> ischemia? But i figured that would be more relevant to a stroke or a PE. But I guess TXA2 does play a role in atherosclerosis so it's the biggest contributor.