Heart Health Archive

Implantable cardiac pacemakers help millions of people live longer and feel better.

Over the past several decades, permanent cardiac pacemakers have become a lifesaving staple of cardiovascular care. These tiny electronic devices consist of a miniature computer that is inserted under the skin of the chest. The unit sends impulses through wires (called leads) that stimulate the heart muscle to beat at regular intervals.

"There are many indications for getting a pacemaker, but nearly all involve correcting a slow heart rhythm or helping the heart to beat more efficiently," says Dr. Peter Zimetbaum, associate professor of medicine at Harvard Medical School. "In some situations, a pacemaker is needed in order to prevent death. In other cases, the device is used to improve overall heart function, which in turn also improves quality of life."

Most Americans don't get the recommended amount of these potentially heart-protecting fats.

Recently, a Harvard Heart Letter subscriber emailed us a question about omega-3 fatty acids, the unique fats abundant in many types of fish that may be linked to a lower risk of cardiovascular disease. Is there a difference, he wondered, between farm-raised and wild-caught salmon in terms of omega-3 fatty acid content?

It's a reasonable question, especially considering that wild salmon is often far more expensive than the farm-raised variety. But how much omega-3 fatty acid do we really need in our diets? And are fish the only source? Here's a brief summary of what you should know about omega-3s.

The longstanding "More Matters" campaign urges Americans to eat more fruits and vegetables (see www.fruitsandveggiesmorematters.org). Evidence to support this healthy habit keeps piling up, with the latest from a study that pooled dietary data from three large, long-term studies that followed more than 187,000 people for an average of over 20 years.

The researchers found that people who ate more whole fruits—especially apples, pears, grapes, and raisins—were less likely to develop high blood pressure than those who rarely ate those foods. As for vegetables, broccoli and carrots appeared to be the best choices for staving off high blood pressure. Fruits and vegetables provide minerals such as potassium and substances called flavonoids, both of which are linked to lower blood pressure. The study was published online in the Dec. 7, 2015, issue of Hypertension.

The strength of your hands may hold clues to the health of your heart. A study in the December 2015 American Journal of Preventive Medicine found that people with stronger handgrips had more favorable findings on measures of their cardiovascular health than those with weaker grips.

The study included more than 4,200 adults ages 20 and older who were part of a nationwide health study. Researchers used a device called a dynamometer to measure each participant's hand strength, adjusting the readings based on body mass index. They found that higher handgrip strength was associated with lower blood pressure, lower triglycerides (a type of fat in the blood), lower blood sugar, and higher HDL (good) cholesterol.

You may assume that there aren't any symptoms for sudden cardiac arrest (SCA), the deadly condition that occurs when your heart suddenly stops pumping. But a study published Jan. 5, 2016, in Annals of Internal Medicine suggests that warning signs are common and often ignored. The most common warning signs were chest pain, breathlessness, palpitations, lightheadedness or fainting, nausea, and vomiting.

Researchers looked at the health information of more than 800 people who experienced SCA, mostly middle-aged men, and discovered that about half of the people had warning signs during the four weeks leading up to SCA and even 24 hours before their hearts stopped. But most of those with warning signs ignored the symptoms. Thirty-two percent of those who called 911 before SCA survived, compared with only 6% among those who didn't call for help. That's because many of the symptoms that led people to call 911 occurred in the hours just before the SCA, so these people were likely to be in a medical care setting when their hearts stopped.

There's encouraging news for people who take dabigatran (Pradaxa), a newer type of blood thinner that's had a rare side effect of uncontrolled bleeding during surgery or accidents. In October 2015, the FDA approved an antidote called idarucizumab (Praxbind), which may be able to reverse dabigatran's blood-thinning effects.

Dabigatran was approved by the FDA in 2010 and welcomed as a convenient alternative to warfarin (Coumadin) for people with certain types of atrial fibrillation, deep-vein thrombosis, or pulmonary embolism. While warfarin is generally safe and inexpensive, it takes about a week for it to become effective, and dosing is so complicated that people taking warfarin need frequent blood tests to see if the dose needs to be adjusted. Dabigatran is effective within two hours and doesn't require dose adjustment or lab monitoring. But dabigatran has caused more episodes of major bleeding than had been expected, without a way to reverse the problem.

A new study suggests greater health benefits with a lower-than-standard number.

Blood pressure has long been one of the best markers of your health. It is a number you can remember and monitor. High blood pressure (hypertension) is linked to a greater risk of heart attacks and strokes.

About one out of three adults has high blood pressure, which is usually defined as a reading of 140/90 millimeters of mercury (mm Hg) or higher.

Sex does not appear to trigger a heart attack or increase your risk for a second one, suggests a study in the Sept. 21, 2015, issue of the Journal of the American College of Cardiology.

Experts looked at 536 heart attack survivors ages 30 to 70 and evaluated their sexual activity in the 12 months prior to their heart attack. Sexual activity was divided into three categories: less than once a month, less than once a week, and once or more per week.

Learning to deal with stress can lower your risk for anxiety, depression, and cardiovascular disease.

The more we learn about women's hearts, the more we realize that they are different from men's. One of the most dramatic differences is a rare heart condition called takotsubo cardiomyopathy, or broken-heart syndrome, that is nine times more common in women than in men. It has been cited as evidence that sudden emotional stress can actually cause death in some women.

Like a heart attack, takotsubo cardiomyopathy strikes suddenly with symptoms such as chest pain and shortness of breath; however, it does not involve clogged arteries. Takotsubo cardiomyopathy is brought on by a surge of stress hormones that literally bend the heart out of shape. As a result, when the main pumping chamber of the heart (the left ventricle) contracts, it balloons out, so it can't eject blood into the arteries effectively.

Women are not only more likely than men to overlook symptoms of heart disease, they are also more likely to skip rehab once they're diagnosed, even though completing the programs has been shown to reduce the risk of death by 26%.

The Cardiac Rehabilitation for Heart Event Recovery (CR4HER) study was designed to test three types of rehab programs to see which was more effective for—and attractive to—women. Researchers randomly assigned 169 female heart patients to 24 sessions over six months in one of three rehab programs. Women in one group were visited three times in their homes by physical therapists and instructed to complete exercises on their own thereafter. Those in the other two groups were assigned to either a mixed-sex or all-female program at a rehabilitation facility.