In-depth

Causes

Diabetic hypoglycemia

Diabetic hypoglycemia — Comprehensive overview covers causes, symptoms and treatment of low blood sugar.

Hyperthyroidism

Hyperthyroidism occurs when your thyroid gland produces too much of the hormone thyroxine — speeding up your metabolism and sometimes leading to serious complications.

Hypoglycemia

Hypoglycemia occurs when you have an abnormally low level of blood sugar (glucose) — your body's main energy source. Various underlying conditions can cause

Long QT syndrome

Long QT syndrome is an electrical disturbance that can cause sudden, rapid heart rates. It can be genetic or a side effect of medication.

Sick sinus syndrome

Sick sinus syndrome is the name for a group of heart rhythm problems in which the heart's natural pacemaker isn't working properly.

Complications

Aortic valve regurgitation

In aortic valve regurgitation, the aortic valve doesn't close tightly, causing blood to leak back into your heart.

Aortic valve stenosis

In aortic valve stenosis, the aortic valve narrows, blocking blood flow. The aortic valve connects your heart to the aorta, your body's main artery.

Atrial fibrillation

Atrial fibrillation is a common heart disorder. Find out more about this heart rhythm problem, including its symptoms, causes and treatments.

 

Eisenmenger syndrome

Eisenmenger syndrome, a complication of congenital heart defects, can be life-threatening if not properly treated. Find out more.

Mitral valve regurgitation

Mitral valve regurgitation occurs when blood flows backward in your heart because the mitral valve closes improperly.

Mitral valve stenosis

In mitral valve stenosis, the mitral valve is narrowed, obstructing blood flow between the chambers on the left side of the heart.

Pulmonary edema

Pulmonary edema occurs when air sacs in the lungs fill with fluid. It's often a life-threatening emergency.

Pulmonary hypertension

High blood pressure affecting only the arteries in your lungs is known as pulmonary hypertension. Discover the symptoms, risk factors and treatment for this condition.

Spontaneous coronary artery dissection

Find out about this rare cause of heart attack in young, healthy people.

Sudden cardiac arrest

Sudden cardiac arrest is a medical emergency. Rapid treatment improves your chances of survival.

Lifestyle and home remedies

Coping with job stress

High stress levels at work can steal the joy from life. Learn how to turn the tables on job stress, starting today.

Relaxation techniques

Relaxation techniques can help reduce stress symptoms and improve your quality of life. Learn simple relaxation techniques you can practice almost anywhere.

Symptoms

Dizziness

Dizziness is one of the most common health concerns. However, few cases of dizziness are due to serious conditions.

Heart palpitations

Heart palpitations are skipped, fluttering or racing heartbeats that aren't usually a symptom of a serious heart problem. Discover the causes and symptoms of this condition.

Shortness of breath

Shortness of breath can be frightening. Most of the time, a heart or lung condition is the cause.

Tachycardia

Tachycardia, a rapid heart rate, is caused by an abnormality in your heart's electrical impulses. Tachycardia can cause serious complications, including sudden cardiac arrest.

Vasovagal syncope

Vasovagal syncope (fainting) is a sudden and brief loss of consciousness that occurs when the blood flow to your brain is markedly reduced.

Tests and diagnosis

Chest X-rays

Even with today's high-tech medical devices, the basic chest X-ray remains an important tool in diagnosing various conditions. Here's a look at how it works.

Echocardiogram

Echocardiogram allows your doctor to see your heart in motion. Here's what you need to know about the test.

Electrocardiogram

An electrocardiogram (ECG or EKG) is a test that provides valuable clues about your heart health. Here's what you need to know about the test.

Apr. 02, 2014