Inappropriate sinus tachycardia

Inappropriate sinus tachycardia is when your heart beats too fast for no good reason. It's like when you run really fast for fun, but instead of stopping when you're tired, your heart keeps running fast even when you're just sitting still.

Normally, your heart beats faster when you're doing exercise or when you're excited. But with inappropriate sinus tachycardia, your heart beats fast even when you're sitting still or sleeping. This can make you feel dizzy, short of breath, and tired all the time.

Doctors aren't exactly sure why this happens, but they think it might be due to a problem with the part of your heart that controls your heart rate. There are different treatments for inappropriate sinus tachycardia, including medicines and surgery, but your doctor will help you decide which one is best for you.