Cardiology Q&A by Dr. Kulick
It is very common to sense your heart beat while lying in bed - rarely is it anything serious, but certainly this sensation will be aggravated if your blood pressure is high. If your blood pressure is normal, it most likely is not a cause of concern. It may also be intensified by any heightened "catecholamine" release (for example, adrenaline) state, such as caffeine consumption, anxiety, fear, etc..
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Last Editorial Review: 12/19/2006