Lightheadedness
The brain and cognitive system heavily depend on blood pumped from your heart to work. Therefore, tachycardia can affect several brain regions, thus making you feel lightheaded. The symptom might last anywhere from several seconds to several minutes. However, it can occur many times during the day, depending on the underlying cause. In advanced cases, tachycardia can even trigger confusion and some mental issues. When you experience lightheadedness or fainting, it is important to call emergency care to prevent some permanent damages to your brain. [5]
