Characterized as abnormal heart rates or rhythms, cardiac arrhythmias have numerous causes. Identifying the root cause of the arrhythmia determines the course of treatment and types of medications used to correct the arrhythmia. Frequently a physician will require the patient to undergo diagnostic tests to determine the exact cause and identify any other facts that may have contributed to the cardiac arrhythmia, or which may cause future disruptions in heart rate and rhythm.
Electrolyte Imbalances
When delicate balances of calcium, potassium, sodium and magnesium become unbalanced, cardiac arrhythmias can occur. Unbalanced electrolytes can speed up or slow down heart rate, create dangerous heart rhythms and even cause death, according to the American Heart Association. Blood test results confirm which electrolyte(s) requires correction, and which oral or intravenous (IV) medication the doctor needs to prescribe.
Dehydration can also throw the heart out of rhythm and manifest a high heart rate. More common in the elderly, this imbalance usually only needs an IV infusion of fluids, according to "Pathophysiology: A 2-in- Reference for Nurses."
Coronary Artery Disease
The plaque from coronary artery disease builds up in the arteries, blocks the free flow of blood in the blood vessels, and drives the heart rate up and creates arrhythmias. When the vessel is again unblocked through medication, lifestyle change, or in-patient procedure, the heart rate and rhythm should return to normal.
Fitness
A healthy heart challenged aerobically by regular cardio exercise functions efficiently at a lower heart rate. A heart that must perfuse a body with extra pounds and a stressed lifestyle, works harder, even at rest, than a fit heart, according to "Pathophysiology." The normal heart rate for a person with excess weight will typically be higher than a fit person's heart rate. The heart rhythm for an unfit person may beat in a constant cardiac arrhythmia.
Illness
A person running a fever will also run a high heart rate. In an effort to pump enough blood to fight the invading organism, the heart will step up its action which raises the heart rate. Illnesses that raise the core body temperature will raise the heart rate, according to "Pathophysiology."
Injury
A heart suffering heart attack or stroke will most likely result in a cardiac arrhythmia. Injury to the heart occurs through a blockage and tissue death results. A heart muscle damaged by tissue death does not pump effectively. Over time, the heart may adapt to its new limitations and regular heart rate and rhythm reestablished with medications and lifestyle changes.
References
- American Heart Association: What Can Arrhythmias Do?
- American Heart Association: What Are Arrhythmias?
- "Pathophysiology: A 2-in-1 Reference for Nurses"; Lippincott Williams & Watkins; 2005
