If you're like most people, you tend to take your heart for granted. Typically, it does its job with little fanfare: beating 100,000 times a day, pumping 2,000 gallons of blood through every organ and system in your body. If you live to a ripe old age, your heart may beat more than 3 billion times.

But millions of hearts never make it that far. The most common reason: coronary heart disease. Occurring when fat and cholesterol combine with other materials to form crusty curds known as "plaques" inside artery walls, the disease narrows and hardens the blood vessels. The condition not only chokes off the heart's supply of oxygen-rich blood, but can contribute to the formation of blood clots that further block arteries, causing a heart attack. Coronary heart disease claims more than half a million American lives every year.

Because one in four Americans has some type of heart disease, it could well affect you or a loved one--possibly sooner than you expect. That's why you should be talking with your doctor now about heart disease. "Heart disease is best managed through a partnership between patient and physician," says Thomas Ryan, MD, director of the Heart Center. "Because so many factors contribute to heart health, the lifestyle choices people make are as important as the diagnostic tools, medication, and surgical and non-surgical interventions that doctors provide. All of these things work together."

According to Ryan, here are eight of the key things you should know about your heart--or, if you're at high risk for heart disease, be working directly with a cardiologist to find out.

1. How can I find out if I'm at increased risk for heart disease or if I have early signs of heart disease?

   If you don't have any symptoms of heart disease (see question #2), the first step is to review your blood cholesterol, blood pressure, age, gender, and family history, as well as your weight, level of physical activity, diet, and tobacco use. Accounting for 50 to 60 percent of your likelihood of developing heart disease, these established risk factors are now often combined with newer risk factors, including inflammatory markers (proteins associated with plaque buildup) and detailed analysis of blood lipids (fats).

   Until very recently, it wasn't possible to find out how much plaque had built up in coronary arteries without undergoing cardiac catheterization, an invasive procedure typically performed only after a patient has had symptoms of heart disease. Today, however, a state-of-the-art imaging technology called cardiovascular CT (computerized tomography) screening can provide what's known as a coronary calcification score, which quantifies the amount of plaque buildup in your arteries. Cardiovascular CT screening is a painless, quick, and highly accurate way for individuals who don't yet have symptoms of heart disease--but are concerned about their risk for developing it--to find out how healthy their arteries are.

   Since a coronary calcification score alone isn't enough to predict a heart event, you should seek a complete risk assessment to help you determine next steps. Duke offers CT screening as part of its Program for Prevention and Treatment of Heart and Vascular Disease, which provides a detailed cardiovascular exam, thorough analysis of additional risk factors, appropriate medication, recommendations for preventive lifestyle strategies, and regular follow-up.

2. What are the symptoms of heart disease?

   Angina (chest pain), fatigue, and/or shortness of breath are often the earliest signs of coronary heart disease. Symptoms may also include a feeling of heaviness, burning, pressure, or tightness in the upper body. Women are more likely to experience sensations such as nausea, heartburn, or stomach pain. If you have one or more of these symptoms, especially if you have other risk factors for heart disease, you should seek expert medical attention. If any of these symptoms is very severe and lasts longer than 10 or 15 minutes, a heart attack could be in progress, so call 911 to request an ambulance immediately--and take an aspirin on the way to the hospital.

   Frighteningly, the vast majority of the million Americans who suffer heart attacks each year have no previous symptoms or history of heart disease. That's why cardiovascular CT screening offers such enormous potential to help head off heart disease. Another new diagnostic technology, cardiovascular MRI (magnetic resonance imaging), can identify damage to the heart caused by previously undiagnosed, "silent" heart attacks. Duke has the only dedicated cardiovascular MRI facility in the Southeast.

3. What does my blood pressure reveal about my heart?

   Blood pressure is the force exerted against artery walls as blood is carried through the circulatory system. The first number on your blood pressure reading is the systolic pressure, or the pressure of blood in the vessels as the heart beats. The second number is the diastolic pressure--the pressure of the blood between heartbeats. Hypertension (high blood pressure) means that the force required for blood flow is greater than normal, and is diagnosed when repeated measurements are greater than 140/90.

   One in four adult Americans have high blood pressure, although nearly a third of them don't know it. (Recent Duke studies have discovered links between high caffeine consumption and high blood pressure, as well as new insights into the significance of "pulse pressure," the difference between the systolic and diastolic readings.) Because untreated high blood pressure raises the risk of heart attack, stroke, and other diseases, you should have your blood pressure screened regularly to facilitate early diagnosis and treatment of related conditions.

4. What should my blood cholesterol be?

   Cholesterol is one of several types of fats, or lipids, that are essential to hormone production and healthy cell function. But excess amounts of cholesterol and triglycerides (another blood fat) in your bloodstream raise your risk of heart attack and stroke. High-density lipoproteins (HDL, the "good" cholesterol, which eats up vascular plaques) should account for up to 60 (or at least 25 percent) of your cholesterol count, and low-density lipoproteins (LDL, the "bad" cholesterol, which deposits plaque within arteries) should not exceed 160. The goal for most adults is a total blood cholesterol level of less than 200--but if a substantial amount of "good" cholesterol pushes the total count above that, a higher overall reading may be just fine.

   Triglycerides are basically fats that float in your blood. Higher levels of triglycerides--caused by fats, sugars, and alcohol intake--have been linked to elevated risk for heart disease. If your lipid profile shows that you have high LDL cholesterol and a triglyceride count of more than 100, you may wish to seek help from a cardiologist.

5. If I do develop heart disease, what medications will I need to take?

   Medications typically prescribed for coronary heart disease include beta-blockers, which lower the heart rate; nitroglycerine and calcium-channel blockers, which relax the arteries; and other drugs that lower cholesterol, reduce blood pressure, break up blood clots, and decrease fluid retention. One of the best heart medicines is also one of the most common: A whole or half aspirin per day can help keep blood from clotting and thus reduce the chances of having a heart attack or stroke--or make a heart attack less severe. As with any other medication, however, don't start taking aspirin without talking to your doctor first.

   New medications, as well as new dosages and combinations of medications, are constantly being investigated in clinical trials at Duke, and the results of this research are tracked in Duke's cardiovascular database--the world's largest. Duke cardiologists practice what is known as evidence-based medicine, which means that they base their care choices on the findings of these and many other scientific studies. Some physicians, however, are not familiar with or do not prescribe the very latest therapies, so be sure to choose a doctor who is aware of the latest studies and uses good science to make important decisions.

6. What other ways is heart disease treated?

   Despite early diagnostics, enhanced prevention strategies, and medical advances, many heart patients require direct intervention to open blocked blood vessels. One of the most popular ways to do this is balloon angioplasty. Performed on more than half a million patients each year, the procedure involves threading a catheter into a coronary artery, then inflating a tiny balloon at the tip to push plaque out of the way.

   Angioplasty has an excellent record of success, but sometimes causes cell inflammation and proliferation that reclogs arteries, a process known as restenosis. The introduction a decade ago of stents--tiny cages that help keep the artery open (including several models that were developed at Duke)--vastly lowered restenosis rates. Today, new types of stents, including several now being tested at Duke, show real promise to further improve angioplasty outcomes by inhibiting restenosis through small doses of radiation or medication.

7. Will I need open-heart surgery?

   Many people can control coronary heart disease with lifestyle changes and medication. For those who have frequent episodes of chest pain or severe blockages in their coronary arteries, however, open-heart surgery--also known as coronary bypass--may be the best option. To perform a coronary bypass, a surgeon removes a section of blood vessel from the leg or chest, then sews it to the clogged artery to carry blood around the blocked section.

   Each year, more than 336,000 Americans undergo open-heart surgery, and for most of them, the procedure is highly successful in clearing blocked arteries and relieving the symptoms of angina. However, bypass is major surgery that requires extensive recuperation, which is why Duke surgeons are among those leading efforts to find less invasive, equally effective alternatives (see box).

8. What are my long-term chances for avoiding--or surviving--heart disease?

   Even the most careful analysis of risk factors--and the most rigorous prevention plan--can't prevent every instance of coronary artery disease. A fundamental puzzle of cardiovascular medicine is why one person can seem like a "walking risk factor" and never have a heart problem, while another can do everything right and have a life-threatening heart event.

   Ultimately, genetics may hold the key to enhancing heart health for everyone. Says Pascal Goldschmidt, MD, chief of cardiology and director of the Duke Center for Cardiovascular Genetics, "When we unravel the genetics of heart disease, physicians will be able to use simple tests to define a patient's susceptibility to heart disease, then select one or two drugs that will work best with their specific genetic makeup." Because genetic factors interact closely with the many other components of heart disease, this leading-edge research will ultimately lead right back to the real heart of the matter: the importance of prevention.