High or Low Potassium Levels & Bradycardia

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Although most of the potassium in your body is located inside your cells, approximately 5 percent of the potassium is located in fluid outside your cells, including your blood. In a healthy individual, this blood potassium level ranges from 3.6 to 4.8 mEq/L. If the amount of potassium in your blood exceeds 4.8 mEq/L, it can lead to an abnormal heart rhythm, called bradycardia.


A normal adult heartbeat ranges from 60 to 100 beats per minute. Bradycardia is a slower-than-normal heartbeat characterized by less than 60 beats per minute. When the heart pumps slower than normal, it does not pump enough blood to meet the needs of your body. As a result, your tissues become starved of oxygen and you may experience weakness, fatigue, dizziness, chest pains, shortness of breath, confusion and memory problems.


MayoClinic.com notes that if bradycardia is severe enough to cause physical symptoms, it also has a high potential to cause serious side effects. Someone with bradycardia may experience fainting spells and eventually develop heart failure. Bradycardia may trigger a sudden heart attack and even cause death. If you experience any of the symptoms of bradycardia, it is important to seek proper medical treatment immediately.


In many cases, correcting potassium levels can treat bradycardia caused by high potassium levels. Treatment may consist of diuretic medications, which trigger your body to release sodium, potassium and water, and intravenous administration of calcium, glucose and insulin, which helps restore mineral balance in the blood. Dialysis may be necessary for those with severe hyperkalemia or for those whose kidneys are not working properly and cannot remove potassium on their own. If treatment for hyperkalemia does not restore normal heartbeat, you may need a pacemaker. A pacemaker is a battery-operated, surgically-inserted medical device that sends electrical signals to your heart to control normal heart rhythm.


Low potassium levels, or blood potassium below 3.6 mEq/L, can lead to an abnormally fast heart rhythm called tachycardia. Tachycardia is characterized by a heart rhythm of more than 100 beats per minute. When the heart pumps too fast, it does not allow ample time for the heart chambers to fill up with enough blood to meet your body’s needs. As with bradycardia, tachycardia causes your body tissues to become starved of oxygen.