Hello and thanks for the query
It seems by reading your mail that your main concern is your tachycardia
. You are already taking beta-blockers but not getting any relief. So try using Calcium channel blockers like Dilzem and Verapamil with beta- blockers in a dose you can tolerate. Consult your cardiologist for this.
These type of tachycardia are not life threatening unless it is associated with chest pain
. But you have a valve prolapse so you have to take care that you don't do any thing that cause chest pain or heaviness like running, heavy Weight lifting etc.
As you ECG recorded HR of 150, I don't thing you need any other examination other than holter which you have already done.
Repeat Holter study after taking Beta-blocker and Calcium Channel blocker to note that they are not causing any bradycardia
. You may need Pacemaker Implantation
in future. So repeat Holter study every year.
Hope you got your answer.