Hi i have inappropriate sinus tachycardia and how do doctors know if its the sinus node or nervous system? is that why some ablations don't work?

EP Test/workup: Rare to really have it. Rule out hormonal and other causes and deconditioning first. Thoughtful ep workup with monitoring and ep study including blockade of adrenergic and cholinergic nervous system a must before considering ablation, which should be thought of as a last ditch option.

Combination: Inappropriate sinus tachycardia (ist) is a difficult entity to treat with ablation. You want to be able to reduce the heart rate enough without leaving the person requiring a pacemaker. A newer medication ivabradine may be used off-label for ist. Good luck.