Bradycardia (Bradyarrhythmia)

Advancing ageHypothyroidism Drugs such as (most commonly used for): Clonidine and other centrally acting alpha-2 adrenergic agonists ( high blood pressure ) Cholinesterase inhibitors ( Alzheimers disease ) Calcium antagonists (high blood pressure, heart disease) Digitalis and other cardiac glycosides (heart failure and arrhythmias ) LithiumBeta-blockers (high blood pressure, heart disease), also used in some eye dropsExposure to certain toxins Cardiac disease, such as: Heart attackDegeneration, calcification, or wearing out of the conduction systemCongestive heart failureValvular failureHeart conditions that are inherited or present at birth (congenital heart defects)Electrolyte imbalances (high or low potassium levels)Sleep apnea Rarely seen with lupus or other collagen vascular diseases Head injuriesHypothermiaHypoglycemia Infectious diseases, such as: DiphtheriaRheumatic feverViral myocarditisLyme diseaseChagas disease Symptoms Some types of bradycardia produce no symptoms. Others may cause noticeable symptoms, such as:

Fainting or loss of consciousness (syncope)Dizziness, sensation of light-headednessWeaknessMild fatigueSensation of your heart fluttering (palpitations)Shortness of breathChest painLow blood pressure (hypotension) Serious forms of bradycardia, such as complete heart block, are medical emergencies. They can lead to loss of consciousness or sudden cardiac arrest . DiagnosisThe doctor will ask about your symptoms and medical history, and perform a physical exam. In particular, the doctor will listen to your heart with a stethoscope.Tests may include:Blood teststo look for certain abnormalities that may explain the bradycardia (eg, electrolytes, glucose, thyroid function, and drug levels)Electrocardiogram (ECG, EKG)a test that records the hearts activity by measuring electrical currents through the heart muscle. Echocardiogram a test that uses high-frequency sound waves (ultrasound) to examine the size, shape, and motion of the heart. Holter monitor or event monitora portable, continuous heart rhythm monitor that you wear as you perform normal daily activities.Exercise stress test a test that records the hearts electrical activity during increased physical activity. Nuclear scanningradioactive material is injected into a vein and observed as it is distributed through the heart muscleto look for coronary artery disease.Coronary angiography x-rays taken after a dye is injected into the arteries; this allows the doctor to look for abnormalities in the coronary arteries of the heart. TreatmentIf no underlying heart disease is detected, the hearts response to exercise is normal, and there are no symptoms of low cardiac output, treatment may not be required. Your doctor may choose to monitor your heart rate and rhythm periodically. People with cardiac symptoms and conditions usually receive treatment.

Treatment for symptomatic bradycardia may include: Discontinuing any medications that slow the heart rateDiagnosis and treatment of any underlying conditionsIntravenous (IV) atropinethis medication may be used to temporarily increase heart rateArtificial pacemakerthis device may be either temporarily or permanently implanted under the skin in the chest wall. Whenever the heart rate drops too low, the pacemaker takes over the job of providing the electrical impulses needed to establish and maintain a normal heart rhythm. Prevention To help prevent bradycardia: Treat underlying conditions that might lead to bradycardia.Carefully follow your doctors directions when using medications (especially those that can potentially cause bradycardia).Check with your physician or pharmacist before using any over-the-counter medication or natural supplement to assure that it will not interact with your other medications Follow general advice for preventing the development of heart disease, including: Maintain an appropriate weight.Consult your doctor about a safe exercise program.Stop smoking.Eat a healthful diet, one that is low in saturated fat and rich in whole grains, fruits, and vegetables. Treat your high blood pressure and/or diabetes . Treat your high cholesterol or triglycerides. RESOURCES:

American Heart Associationhttp://www.americanheart.org National Heart, Lung, and Blood Institute, National Institutes of Healthhttp://www.nhlbi.nih.gov CANADIAN RESOURCES: Heart and Stroke Foundation of Canadahttp://ww2.heartandstroke.ca University of Ottawa Heart Institutehttp://www.ottawaheart.ca/UOHI/Welcome.do References: American Heart Association website. Available at: http://www.americanheart.org . Cardiac arrhythmias. McGill University website. Available at: http://sprojects.mmi.mcgill.ca . Accessed November 21, 2002. Fleg J. Arrhythmias and conduction disturbances. In: Beers MH, Berkow R, eds. The Merck Manual of Geriatrics [online]. Merck & Co.; 2000:486. Hurst's The Heart . 11th ed; 2004. Livingston M. Sinus bradycardia. Emedicine Journal [serial online].2001 Jul 31; topic 534. National Heart, Lung and Blood Institute, National Institutes of Healthwebsite. Available at: http://www.nhlbi.nih.gov . Last reviewed February 2008 by Michael J. Fucci, DOPlease be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.