Well, that's scary! your resting heart rate is taken on a wearable? This is routinely 177? Wowza, that probably doesn't feel good. I assume you gave up all of the good stuff, caffeine, alcohol, smoking, and you are working on sleep? Those are the lifestyle things they always recommend. So, there are three types of tachycardia. You seem to be saying they ruled out sinus which would leave superventricular and ventricular. They do have treatment options for both of those. Albeit I'm sure nothing you really want to hear or do at 32 years old!! They are saying you had an infarction? Wow. That's scary. That is involved in tachycardia sometimes especially ventricular. The rest of your numbers see to be normal or near normal? Correct?
I would continue to follow up with your cardiologist or go to see one if you haven't yet. There is a possibility your tachycardia is related to the possible heart attack that was indicated on the ekg but that type of result can actually be a false positive result simply because the tech did not put the electrodes on correctly. You really should have further testing, another ekg and an echo to rule out damage to the heart. You may also need to see a heart rhythm cardiologist to determine the source of the tachycardia. It can be from a number of causes from the simple, low electrolytes or dehydration to something more serious but usually tachycardia isn't anything to worry about but it is important to get to the root of things so that you don't put excessive stress on your heart over time. Best of luck getting it sorted out and keep us posted but do continue to follow up with your doctor to get answers. Take care.