Hi,
About 1.5 years ago I started to have episodes of tachycardia, with palpitations, fatigue, shortness of breath, etc. My resting heart rate was usually around 80-100 bpm, but I would have random episodes where my heart rate would race around 150 or higher. After being evaluated by a cardiologist where tests (echo, 24 holter monitor) all came back inconclusive, my problem was simply passed off as anxiety. My general practitioner who also followed my situation, wanted to lower my heart rate to eliminate the symptoms of palpitations, etc and prescribed Propranolol (60 mg extended release) about a year later. The beta blocker made me feel much better and significantly lowered my baseline heart rate, eliminating the horrible symptoms as well as the instances in which my heart would race. However, I did notice that I had skipped beats while on the Propranolol. About 5 months after starting the beta blocker, I had an episode of SVT that landed me in the hospital (240 bpm). I had never had a similar episode before. The cardiologists and electrophysiologists at the hospital switched me to Verapamil and scheduled me for an EP study and ablation. The Verapamil did not lower my heart rate at all and I suffered terrible bouts of tachycardia, much worse than I had ever had before. It has now been 5 days since my EP study and ablation, which was said to be successful. However, I am still having constant tachycardia, with a resting HR of 80-100, which is elevated to 100-150 upon standing, walking around, minimal exertion, etc. The electrophysiologists that did the ablation mentioned that they noticed that I have a very irregular heart rate that is very sensitive to any kind of vagal changes. Does this mean I possibly have IST? They also said I should start taking the Propranolol again if my heart rate was elevated/bothering me. Could my heart rate be elevated due to the ablation procedure itself or is it likely that I have IST? Since the tachycardia is still causing symptoms, should I go back on the Propranolol even though it had previously caused my to feel more skipped beats? I should also mention that I stopped taking birth control pills after many years shortly before having the episode of SVT and that the tachycardia worsens depending on where I am in the monthly cycle. Could my heart rate therefore also be sensitive to hormonal changes?
Thanks so much in advance!