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Coronary Heart Disease




Palpitations or irregular-feeling heartbeats.

Shortness of breath.

Chest pain.

Dizziness, lightheadedness, and fainting spells.

Mental confusion.

Loss of consciousness.

In some cases there may be no symptoms.

When To Call Your Doctor

Call an ambulance if you experience severe chest pain, shortness of breath, or prolonged palpitations.

Call an ambulance if someone loses consciousness. If heartbeat or breathing has stopped, perform cardiopulmonary resuscitation (CPR).


What Are They?

Arrhythmias are disturbances in the normal rhythm of the heartbeat. An occasional palpitation or fluttering is usually not serious, but a persistent arrhythmia may be life-threatening.

There are many different types of arrhythmias. The heart may beat too rapidly (tachycardia) or too slowly (bradycardia), or it may beat irregularly. Atrial fibrillation and atrial flutter are common arrhythmias, which lead to an irregular and sometimes rapid heart rate. These atrial arrhythmias may interfere with the heart’s ability to pump blood properly from its upper chambers (atria). The atria may not always empty completely, and blood remaining there too long may stagnate and clot. Such clots may travel to other parts of the body, where they may cause blockages in the blood vessels that lead to the limbs, brain, or heart.

In ventricular fibrillation, the lower chambers of the heart (ventricles) quiver feebly instead of contracting powerfully. This is the most severe type of arrhythmia, causing death in minutes unless medical assistance is obtained immediately.

What Causes Them?

Disorders that damage the heart or its valves, such as endocarditis, myocarditis, and rheumatic fever.

Disorders of the thyroid gland.

Chest- or heart-surgery patients may develop an arrhythmia soon after the operation.

Dehydration or depletion of potassium or other electrolytes.

Some drugs, including digitalis, stimulants, and diuretics, as well as overdoses of cocaine, marijuana, or antidepressants.

Injury to the heart due to a heart attack.

Risk increases with smoking, excess consumption of caffeine or alcohol, advancing age, high blood pressure, kidney disease, and stress.


Engage in regular aerobic exercise. Avoid cigarettes, illegal drugs, and excessive amounts of alcohol and caffeine. Try to reduce emotional stress.

Carefully follow instructions for prescription drugs.


Electrocardiography (ECG) is performed to monitor the electrical impulses that control heartbeat; Holter monitoring (portable ECG) may be required for a brief period (usually 24 hours).

Blood pressure and blood tests.

Exercise stress test.

Chest x-rays and angiography (injection of a contrast material into an artery to produce a clear x-ray image of the blood vessels).

Echocardiography (use of ultrasound to map the heart’s movements and structure).

An electrophysiology study (a sophisticated electrical test of the heart involving electrical monitoring and stimulation inside the heart) may be performed.


Antiarrhythmic drugs (such as a beta-blockers, calcium channel blockers, amiodarone, or procainamide) may be prescribed.

Anticoagulants (such as aspirin or warfarin) may be prescribed to prevent the formation of blood clots, particularly for atrial arrhythmias.

Digitalis (a drug that slows the response of the ventricles to the rapid impulses coming from the atria) may be prescribed for those with atrial arrhythmias.

Defibrillation—a jolt of electricity applied to the chest by an emergency medical team—may restore normal heart rhythm if administered within a few minutes of the onset of ventricular fibrillation. An electric shock (cardioversion) may also be administered under nonemergency conditions to correct atrial arrhythmias.

A pacemaker may be implanted in the chest if the heart rate is dangerously slow.

An ablation procedure (destruction of heart tissue responsible for the arrhythmia) may be recommended. It can often be performed during an electrophysiology study.

Surgery may be done to interrupt an abnormal electrical pathway in the heart, replace a damaged heart valve, or bypass blocked coronary arteries.


From Johns Hopkins Symptoms and Remedies, the complete home medical reference. You can order this book now on our secure server.



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