Thanks for posting your query.
As you had mentioned that you had an episode of SVT
that means you were admitted in ICU
for control of heart rate
. Kindly check the discharge card which the hospital might have provided you at the time of discharge.
It is very difficult to name you the precise name of the medicine , because the medicines which are used to decrease heart rate are many & it depends on the patients condition at the time of admission which medicine to be given.
Please consult cardiologist
who had treated you at that time to get the details of your medicine.
Wish you a Good Health.