Sinus tachycardia refers to a heartbeat of over 100 beats per minute. While this is typically a response to stress and not a cause for concern, it can sometimes arise without an immediate explanation which may be indicative of other underlying health conditions. Symptoms may include chest palpitations and pain, shortness of breath, fatigue, dizziness, and fainting. While it can generally be managed with a healthy lifestyle, some people may require medication, medical procedures, or therapy to control their sinus tachycardia.