Palpitations are often not serious. However, it depends on whether or not the sensations represent an abnormal heart rhythm (called an arrhythmia). You are more likely to have an abnormal heart rhythm if you have: Known heart disease at the time the palpitations begin, Significant risk factors for heart disease, An abnormal heart valve, or An electrolyte abnormality -- for example, low potassium.
Heart palpitations can be caused by: Exercise, Anxiety, stress, fear, Fever,Caffeine, nicotine, cocaine, diet pills, Overactive thyroid, Anemia, Hyperventilation, Low levels of oxygen in your blood, Medications such as thyroid pills, asthma drugs, beta blockers for high blood pressure or heart disease, or anti-arrhythmics (medications to treat an irregular heart rhythm can sometimes cause a different irregular rhythm) Mitral valve prolapse -- the valve that separates the left upper chamber (atrium) from the left lower chamber (ventricle) of the heart does not close properly, and Heart disease.
Reducing stress and anxiety can help lessen your heart palpitations. Try breathing exercises or deep relaxation (a step-by-step process of tensing and then relaxing every muscle group in your body) at the time of your heartbeat sensations. Also, consider practicing yoga or tai chi on a regular basis to reduce the frequency of your palpitations.
Keep a record of how often you have palpitations, when they happen, how long they last, your heart rate at the time of the palpitations, and what you are feeling at the time. This information may help your doctor figure out both their seriousness and the cause.
Once a serious cause has been ruled out by your doctor, try NOT to pay attention to heart palpitations, unless you notice a sudden increase or a change in them.
However Call 911 if you have fainted or lose consciousness. You have shortness of breath, chest pain, unusual sweating, dizziness, or lightheadedness.
Call your doctor right away if: You feel frequent extra heartbeats (more than 6 per minute or coming in runs of 3 or more). You have risk factors for heart disease like high cholesterol, diabetes, or high blood pressure. You have new or different heart palpitations. Your pulse is more than 100 beats per minute (without exercise, anxiety, or fever).
I had heart palpitations for years, then was diagnosed with both Hyper/Graves'and MVP. Treatment for my hyperthyroidism corrected the palpitations and I have no longer suffer with it since.
Hope this helps.