Complications

Unless a heart condition is causing your heart palpitations, there's little risk of complications. For palpitations caused by a heart condition, possible complications include:

• Fainting. If your heart beats rapidly, your blood pressure can drop, causing you to faint. This might be more likely if you have a heart problem, such as congenital heart disease or certain valve problems.
• Cardiac arrest. Rarely, palpitations can be caused by life-threatening arrhythmias and can cause your heart to stop beating effectively.
• Stroke. If palpitations are due to a condition in which the upper chambers of the heart quiver instead of beating properly (atrial fibrillation), blood can pool and cause clots to form. If a clot breaks loose, it can block a brain artery, causing a stroke.
• Heart failure. This can result if your heart is pumping ineffectively for a prolonged period due to an arrhythmia, such as atrial fibrillation. Sometimes, controlling the rate of an arrhythmia that's causing heart failure can improve your heart's function.