Although Wikipedia will do in a pinch, in the long run you really do have to dig deeper.
So where do you start, if a sentence reads like a web of jargon? Don’t panic. Remind yourself that somewhere in there are subjects, verbs, and objects. Google unfamiliar words. Then try to summarize that whopper out loud. Make a list of acronyms and what they mean. And move on to the next one.
Think about how the terms can be categorized. For example, there is a spectrum of symptomatic heart disease. On the low end, you have stable angina (chest pain that predictably appears during strain or exercise). Next comes unstable angina (chest pain that pops up out of nowhere), followed by what is commonly called a ‘heart attack.’ Myocardial infarction (MI) itself can be divided according to its severity based on ECG results: non-ST-segment elevation MI and ST-segment elevation MI (aka NSTEMI and STEMI). Everything worse than unstable angina can be grouped as acute coronary syndromes (ACS).
I could probably recite this in my sleep by now, but at one point it had me in knots. And reading the paragraph I just wrote, I understand why. Whew.