Heart Health Archive

Heart attacks are responsible for most cases of cardiac arrest. Know the warning signs—and what to if you witness a cardiac arrest.

Recently, a Harvard Heart Letter reader sent us an email asking about sudden cardiac arrest. This much-feared event occurs when the heart abruptly and unexpectedly stops beating. Each year, nearly 380,000 people in the United States experience cardiac arrest, and only about 10% survive.

"What are the causes and contributing factors? Are there early symptoms before the arrest occurs? And can it occur in a seemingly healthy middle-aged person?" she asked. Sudden cardiac arrest remains challenging to both predict and prevent. But there are definitely ways to lower your risk — and things that everyone should know (see "Recognize and react to sudden cardiac arrest").

Most people don't need an electrocardiogram before a minor, low-risk procedure. Major surgery is different.

If you've ever had surgery, you may recall having a preoperative evaluation, sometimes referred to as "clearance" for surgery. These check-ups often occur days or weeks prior to a planned, non-cardiac surgery and typically involve a physical exam. You also may get blood tests, x-rays, and an electrocardiogram (ECG) — a quick, painless test that records your heart's electrical activity.

"These evaluations are designed to assess your chances of experiencing a heart-related problem during the surgery," says Dr. Brendan Everett, director of the general cardiology inpatient service at Harvard-affiliated Brigham and Women's Hospital. The term "clearance" is misleading, as there is no way to guarantee you won't have complications. Still, knowing ahead of time about any heart-related risks you may have enables the surgeon to better prepare for possible complications and have a backup plan available, says Dr. Everett.

Until recently, cardiac amyloidosis was considered rare and untreatable.

As America's population ages, heart failure diagnoses are on the rise — especially the type caused by a stiff, thickened heart muscle. The heart pumps adequately but can't relax, causing fluid to back up into the lungs, leading to symptoms such as breathlessness and fatigue.

Doctors refer to this form of heart failure as "heart failure with preserved ejection fraction," or HFpEF. About half of all heart failure diagnoses fall into this category, yet the condition has proved challenging to treat. But cardiologists are now recognizing that about 10% to 15% of people with stiff, failing hearts may have cardiac amyloidosis.

Sunflower seeds, which are harvested from the centers of large, yellow-petaled flowers, have a long and interesting history. Native American Indians cultivated sunflowers some 8,000 years ago, using the seeds to make meal for bread.

Today, farmers grow two main types of sunflowers. Those with solid black hulls have extra-oily seeds, which are pressed into sunflower oil or used in bird feeders. Those with black-and-white-striped hulls are used in food. In the late 1960s, chewing a mouthful to extract the small seeds became popular among baseball players, allegedly as a substitute for chewing tobacco. In the 1970s, hulled sunflower seeds gained a following among vegetarians and natural-food enthusiasts.

The COVID-19 pandemic has shown that people are capable of changing their behavior— surprisingly fast—when the stakes are high. Can we apply that resolve to other persistent issues that affect our health and quality of life?

People with disease of the left main coronary artery usually have the option of bypass surgery or angioplasty and placement of a stent. Two recent studies comparing these choices came to different conclusions about which is more effective.

Millions of Americans have trouble sleeping, a factor that is key to cardiovascular health. Two recent studies examined the relationship between sleep and heart health, and between sleep and dietary choices.

Most people with type 2 diabetes also have obesity. Weight-loss surgery has a positive impact on risk factors for heart disease, and a recent study found that this surgery significantly reduced the risk of death in people with obesity and diabetes.

New studies shed light on the role of aspirin for people without a previous heart attack or stroke.

 Image: © dszc/Getty Images

It costs just pennies per pill, doesn't require a prescription, and may be lifesaving for some people. But daily low-dose aspirin doesn't make sense for everyone. Now, three major studies that examined the benefits and risks of this widely used drug may alter the advice about who should take aspirin.

"Aspirin remains a cornerstone of treatment after a heart attack or stroke. But the question of whether people with a low to moderate risk of heart disease should take aspirin is a really important one," says Dr. Christopher Cannon, a cardiologist at Brigham and Women's Hospital and professor of medicine at Harvard Medical School. Tens of millions of people in the United States fall into that low-to-moderate-risk category. But until now, there weren't many large trials that included those people, he notes.

You can begin to reduce your "bad" LDL cholesterol naturally by making a few simple changes in your diet.

If your cholesterol is creeping upward, your doctor has probably told you that diet and exercise—the traditional cornerstones of heart health—could help to bring it down. And if you'd prefer to make just one change at a time to lower your cholesterol naturally, you might want to begin with your diet. A major analysis of several controlled trials involving hundreds of men and women found that dietary changes reduced LDL and total cholesterol while exercise alone had no effect on either. (However, adding aerobic exercise did enhance the lipid-lowering effects of a heart-healthy diet.)