Heart Health

The heart beats about 2.5 billion times over the average lifetime, pushing millions of gallons of blood to every part of the body. This steady flow carries with it oxygen, fuel, hormones, other compounds, and a host of essential cells. It also whisks away the waste products of metabolism. When the heart stops, essential functions fail, some almost instantly.

Given the heart's never-ending workload, it's a wonder it performs so well, for so long, for so many people. But it can also fail, brought down by a poor diet and lack of exercise, smoking, infection, unlucky genes, and more.

A key problem is atherosclerosis. This is the accumulation of pockets of cholesterol-rich gunk inside the arteries. These pockets, called plaque, can limit blood flow through arteries that nourish the heart — the coronary arteries — and other arteries throughout the body. When a plaque breaks apart, it can cause a heart attack or stroke.

Although many people develop some form of cardiovascular disease (a catch-all term for all of the diseases affecting the heart and blood vessels) as they get older, it isn't inevitable. A healthy lifestyle, especially when started at a young age, goes a long way to preventing cardiovascular disease. Lifestyle changes and medications can nip heart-harming trends, like high blood pressure or high cholesterol, in the bud before they cause damage. And a variety of medications, operations, and devices can help support the heart if damage occurs.

Heart Health Articles

Implantable Cardioverter Defibrillator (ICD)

An implantable cardioverter defibrillator (ICD) is a potentially lifesaving medical device that is placed inside the body. An ICD treats life-threatening abnormal heart rhythms (called arrhythmias), including ventricular fibrillation, which makes the heart's large muscular chambers (the ventricles) quiver without actually squeezing and pumping. When this happens, there is no real heartbeat and not enough blood flows to the brain or other organs, including the heart. As a result, a person with ventricular fibrillation passes out and can die within minutes. An ICD is made of two parts. The pulse generator looks like a small box. It is implanted under the skin below the collarbone. The box contains a lithium oxide battery (which lasts about five to nine years) and electrical components that analyze the heart's electrical activity. Connected to the pulse generator are one or more electrodes, which travel to the heart. When the ICD senses an abnormal heart rhythm, it administers a brief, intense electrical shock to the heart, correcting the abnormal rhythm. Many people say that the shock feels like being punched in the chest, although the amount of discomfort varies. (Locked) More »

Cardiac Catheterization

Cardiac catheterization is a procedure in which a heart specialist inserts a small tube (catheter) through a large blood vessel in the arm or leg, and then passes the tube into the heart. Once inside the heart, doctors use the catheter to evaluate how the heart is working by measuring pressure and oxygen levels within the heart's chambers. Through the catheter, doctors inject a special dye that provides an X-ray image of the heart's internal structure and blood flow patterns. The procedure is often done to look for narrowed and blocked coronary arteries. The X-ray dye also is injected into each of the three largest coronary arteries. This is called coronary angiography. (Locked) More »

Holter Monitor and Event Monitor

A Holter monitor is a portable EKG device that records your heart rhythm over time, outside the hospital or doctor's office. Whereas a regular EKG examines your heart's electrical activity for a few seconds, the Holter monitor examines changes over a sustained period of time-usually a 24- to 48-hour period-while you go about your daily activities and even while you sleep. One type of Holter monitor, called an "event monitor," can be used to record rhythms over a longer time, such as a 30-day period. Doctors use Holter monitor or event monitor tests to evaluate symptoms that come and go and that might be related to heart-rhythm changes or coronary artery disease. (Locked) More »

Heart Valve Replacement

Sometimes a natural heart valve that is not working properly needs to be replaced surgically with a prosthetic valve. A prosthetic valve is a synthetic or tissue substitute for the natural valve. It is designed to mimic the natural valve's normal opening and closing motions. A prosthetic valve can replace any of the three heart valves – aortic, pulmonary or tricuspid. Prosthetic heart valves are divided into two basic categories: synthetic mechanical valves and biological valves made of human or animal tissue. What It's Used For The reasons for a heart valve replacement vary slightly, depending on which of the four heart valves is involved. As a general guide, however, you may need a valve replacement for any of the following reasons: You have significant valve narrowing (stenosis) or leaking (regurgitation) that is causing severe cardiac symptoms, such as angina (chest pain), shortness of breath, syncope (fainting spells) or symptoms of heart failure. Although your cardiac symptoms are not yet severe, diagnostic tests show that you have valve stenosis or regurgitation that is beginning to seriously affect your heart function. You have milder valve stenosis or regurgitation, but you need open heart surgery for another reason (such as coronary artery bypass). Your problematic heart valve can be replaced during this open-heart procedure, correcting the situation before it has the chance to deteriorate. Your heart valve has been damaged severely by endocarditis (infection of the heart valve), or you have endocarditis that is resistant to antibiotics. You already have a prosthetic heart valve, but it needs to be replaced because it is leaking or malfunctioning, because you are having recurring blood clots or infection on the heart valve, or because you are having bleeding problems related to anticoagulants. (Locked) More »

Coronary Artery Bypass Surgery

Coronary artery bypass surgery is a procedure that detours (or bypasses) blood around a blocked section of one or more coronary arteries. It is also called coronary artery bypass grafting or CABG (pronounced "cabbage"). Coronary arteries are the blood vessels that supply the heart with oxygen and nutrients. You have several coronary arteries. They are named for their location. For example, your doctor may speak of the left main coronary artery, left anterior descending artery or the right coronary artery. Coronary artery disease is any illness that damages these arteries. Coronary artery disease is often called "coronary atherosclerosis." Atherosclerosis is the narrowing of arteries caused by the buildup of fat and cholesterol. This buildup is called plaque. Plaque can decrease the amount of blood that reaches the heart. The plaque can tear and cause a blood clot. The clot can block your artery and stop the flow of blood to your heart. This can cause a heart attack. (Locked) More »

Long QT Syndrome

Long QT syndrome is an uncommon inherited condition — meaning it's caused by genes passed on to you from your parents. The electrical activity of heart cells is controlled by a set of channels that pump minerals, such as sodium and potassium, in and out of cells. If you inherit genes that cause alterations in these channels, it can affect the action of heart cells. Normally, an electrical impulse starts in the sinus node, located in the upper chamber of the heart. The electrical impulse then travels down to the lower chambers of the heart, called the ventricles, causing contraction of the ventricles' muscle cells. This contraction causes the blood to flow out of your heart, like how squeezing a balloon filled with water, but not tied at the top, causes the water to squirt out the top. (Locked) More »


Pericarditis is an inflammation of the pericardium, the saclike membrane around the heart. Pericarditis can be triggered by many, very different medical conditions. Often the exact cause cannot be identified. Doctors call this idiopathic pericarditis. In many people with pericarditis, the initial trigger is a viral infection. However, the inflammation may not be a direct result of the infection. Instead, the virus may stimulate the immune system to attack and inflame the pericardium.   (Locked) More »

Cardiac Arrhythmias

Symptoms of specific arrhythmias include: Sinus node dysfunction - There may not be any symptoms, or it may cause dizziness, fainting and extreme fatigue. Supraventricular tachyarrhythmias - These can cause palpitations (awareness of a rapid heartbeat), low blood pressure and fainting. Atrial fibrillation - Sometimes, there are no symptoms. This can cause palpitations; fainting; dizziness; weakness; shortness of breath; and angina, which is chest pain caused by a reduced blood supply to the heart muscle. Some people with atrial fibrillation alternate between the irregular heartbeat and long periods of completely normal heartbeats. A-V block or heart block - First-degree A-V block does not cause any symptoms. Second-degree A-V block causes an irregular pulse or slow pulse. Third-degree A-V block can cause a very slow heartbeat, dizziness and fainting. VT - Non-sustained VT may not cause any symptoms or cause a mild fluttering in the chest. Sustained VT usually causes lightheadedness or loss of consciousness and can be lethal. Ventricular fibrillation - This causes absent pulse, unconsciousness and death. (Locked) More »

Secondary Hypertension

In most cases of high blood pressure (hypertension), there is no known cause. About 6% of the time, however, high blood pressure is caused by another condition or disease. When this happens, it is called secondary hypertension. Most of the conditions that cause secondary hypertension involve the overproduction of one of the body's hormones. Some of the medical problems that can cause secondary hypertension include: Kidney disease. Secondary hypertension can be related to damaged kidneys or to an abnormal narrowing of one or both renal arteries. The renal arteries are the major blood vessels that bring blood to each kidney. When the kidney's blood supply is reduced by a narrowing (called renal artery stenosis), the kidney produces high levels of a hormone called renin. High levels of renin trigger the production of other substances in the body that raise blood pressure, particularly a molecule called angiotensin II. Adrenal disease. The adrenal glands sit on top of the kidneys and produce several hormones that help regulate blood pressure. Sometimes, one or both adrenal glands make and secrete an excess of one of these hormones.   (Locked) More »

Immune Thrombocytopenic Purpura (ITP)

Immune thrombocytopenic purpura (ITP), also known by the shorter name Immune Thrombocytopenia (same abbreviation ITP), can be understood by looking at the three terms that make up its name: Immune indicates that the illness is caused by the immune system, which makes cells and antibodies that attack the person's own platelets — the parts of the blood that help the blood to clot. Thrombocytopenic means that the illness is related to low levels of thrombocytes, another name for platelets. Platelets are produced in the bone marrow (the central lining of the bones). The body needs adequate numbers of functioning platelets to allow blood to clot and to limit bleeding if you are cut or experience other types of trauma. Purpura means that the illness produces a red or purple rash that is caused by bleeding under the skin. This is only one manifestation of the disease In short, ITP is an illness in which unusually low levels of platelets lead to purpura and other forms of abnormal bleeding. (Locked) More »