What is your "increased heart rate" at? How many beats per minute?
You say some swollen ankles at the end of the day, are you on your feet a lot? How is your weight? Just thinking swelling may be due to physical stress, not heart problems.
Sugar and caffeine can (do) cause an increase in HR in many (most) people.
I have no specific knowledge of ARVD, perhaps someone else will comment on that point.
ARVD is a condition where the right ventricle is infiltrated by fatty-fibrous tissue. This creates electrical circuits, which conduct electricity. This then leads to lots of PVCs, and tachycardia.
An exprerienced Electrophysiologist can tell from an EKG the likely location of the origin of the PVCs. If the EKG shows PVCs from multiple places and multitple shapes, then ARVD is suspected and an MRI is appropriate. You should ask your Cardio the reason for checking for ARVD. I think an MRI is about $2000.
Thank you for your comments. I am not overweight, and my ankles are not so swollen that it is bothersome--yet, I'm just trying to include all symptoms. I was actually diagnosed with RBBB which the cardio said was the reason for the PVCs. Now, I don't know why she is insistant on the MRI. She said it was to "rule out" ARVD, but I have not experienced the tachycardia and can easily tolerate exertion without symptoms.
Your cardiologist is just trying to be "safe". ARVD is a serious condition and should be diagnosed as early as possible. There are several tests, most cost less than an MRI I think, that could help, including an echocardiogram. This gives a very good picture of the heart physically. I think it cost at least $1,000, maybe more, so it may not be a lot less costly than an MRI, and perhaps not as effective.
I can't recommend not getting an MRI, but if it were me I'd probably be thinking first about how I might get insurance, including seeing what comes out of Washington this year. This is not my recommendation for you as it has risks, but I think that might be what I'd do. In retrospect I've had a job that included pretty good health insurance, so I always had that back-stop. As is the case with most insurance, there are deductibles, and now that I have heart problems it still cost me a few thousand each year even with insurance.
Johns Hopkins is conducting ARVD research and has pinpointed several EKG abnormalities that specifically indicate ARVD as a posslbe diagnosis. It might be more economical for you to send your info (ekg etc) to them and get their opinion about the need for a further investigation. If they tell you ARVD is possible/likely etc then you can find a way to pay for the Cardiac MRI, if not then you could feel good about delaying/modifying your current Dr's treatment suggestions. Just a thought. The lead Dr. for ARVD at Hopkins is Hugh Calkins. Best of luck.