Month: September 2022

Love isn’t the only reason your heart may skip a beat. While abnormal heartbeats can be alarming, they’re usually harmless. They occur for different reasons. Which types are common — and when should you be concerned?

Palpitations

Your heartbeat normally keeps a predictable pace: speeding up when you’re active and slowing down when you rest. But many people notice odd heart sensations called palpitations at least once in a while. People usually say it feels as though their heart has skipped a beat, or is racing or pounding.

“One common scenario is a person who feels their heart is racing, but if you look at their electrocardiogram (ECG), It’s totally normal,” says cardiologist Alfred E. Buxton, professor of medicine at Harvard Medical School.

A heightened awareness of normal heart rhythms may occur more in people who wear smartwatches with heart rate monitors, he adds. “People with a resting heart rate of 60 beats per minute are concerned when their heart rate goes up to 90, but that’s still in the normal range,” he says.

Ectopic beats

The sensation that your heart has skipped a beat also occurs when the heart’s upper chambers (atria) or lower chambers (ventricles) contract slightly earlier than normal.

During the next beat, the atria pause a bit longer to get back into a normal rhythm. The heart’s lower chambers (ventricles) then squeeze forcefully to clear out the excess blood that accumulates during that pause. They also can contract earlier than usual, which may make you feel like your heart has briefly stopped and restarted.

Known as ectopic beats, both types of these premature contractions may cause a brief pounding sensation. However, this is nothing to worry about. “I often tell my patients that the fact they feel these beats is usually a sign that their heart is healthy. A weak, sick heart can’t exert a forceful beat,” says Dr. Buxton.

AV block and bundle branch block

Electrical impulses tell your heart to pump. They travel through the right and left sides of your heart. But sometimes the impulses travel more slowly than normal or irregularly, causing a condition called AV block. There are various degrees of AV block, some benign, others associated with extremely slow heart rates that may be dangerous.

Another electrical conduction irregularity is a bundle branch block. This results from an abnormal activation pattern of the ventricles that squeeze blood out of the heart to the rest of the body. The most common is right bundle branch block, which usually doesn’t cause obvious symptoms. It may be spotted during an ECG, and can simply reflect the gradual aging of the heart’s conduction system. However, sometimes a right bundle branch block is caused by underlying damage from a heart attack, heart inflammation or infection, or high pressure in the pulmonary arteries.

A left bundle branch block may occur as an isolated phenomenon, or may be caused by a variety of underlying conditions. In some cases, left bundle branch block may lead to abnormal function of the left ventricle, a condition that is sometimes corrected by special pacemakers.

Atrial fibrillation

An electrical misfire in the atria can cause atrial fibrillation, an uncoordinated quivering of the atria that raises the risk for stroke. Commonly known as afib, this heart rhythm problem can come and go, lasting only a few minutes or sometimes for days or even longer. And while some people report a fluttering sensation in their chest or a rapid, irregular heartbeat during an episode of afib, other people don’t have any symptoms.

Certain smartwatches that can record a brief ECG may be able to detect afib. But Dr. Buxton says they’re not sensitive or specific enough to reliably diagnose the problem. “Sometimes the watch tells you that you have afib when you don’t, or vice versa,” he says.

The heart rate monitoring feature may be helpful, however. In people younger than 65, the heart rate can soar to 170 beats per minute or higher during a bout of afib. But for those in their 70s and 80s, who are more likely to have afib, the heart rate usually doesn’t get that high.

When should you be concerned about irregular heartbeats?

An irregular heartbeat, such as racing, fluttering, or skipping a beat, is usually harmless. Even in cases when palpitations are frequent and bothersome (which occurs rarely), reassurance may be the only treatment needed.

But you should contact your doctor if you notice other symptoms accompanying an unusual heartbeat, such as feeling

• chest pain
• dizzy
• lightheaded
• tired
• breathless
• as though you’re going to faint.

People who have been told they have a bundle branch block may need periodic ECGs to monitor their condition. They should also be alert to symptoms such as dizziness or fainting, which can happen if the blockage worsens or occurs on both sides and causes a low heart rate.

About the Author

Julie Corliss, Executive Editor, Harvard Heart Letter

Julie Corliss is the executive editor of the Harvard Heart Letter. Before working at Harvard, she was a medical writer and editor at HealthNews, a consumer newsletter affiliated with The New England Journal of Medicine. She … See Full Bio View all posts by Julie Corliss

About the Reviewer

Robert H. Shmerling, MD,

Senior Faculty Editor, Harvard Health Publishing; Editorial Advisory Board Member, Harvard Health Publishing

Dr. Robert H. Shmerling is the former clinical chief of the division of rheumatology at Beth Israel Deaconess Medical Center (BIDMC), and is a current member of the corresponding faculty in medicine at Harvard Medical School. … See Full Bio View all posts by Robert H. Shmerling, MD

Hot flashes and sleep or mood changes are well-known, troublesome symptoms that may occur during perimenopause and menopause. Now, one survey suggests nearly 80% of midlife women use cannabis to ease certain symptoms, such as mood issues and trouble sleeping.

Mounting numbers of US states have legalized marijuana for medical or recreational use in recent years. This wave of acceptance runs alongside skepticism in some quarters concerning FDA-approved menopause treatment options, including hormone therapy. But a lack of long-term research data surrounding cannabis use has led one Harvard expert to question how safe it may be, even while acknowledging its likely effectiveness for certain menopause woes.

“More and more patients tell me every year that they’ve tried cannabis or CBD (cannabidiol, an active ingredient in cannabis), particularly for sleep or anxiety,” says Dr. Heather Hirsch, head of the Menopause and Midlife Clinic at Harvard-affiliated Brigham and Women’s Hospital. “Adding to its appeal is that cannabis is now legal in so many places and works acutely for a couple of hours. You don’t need a doctor’s prescription. Socially, it may be easier to justify than using a medication. But why is there a movement toward saying okay to something that has unknown long-term effects, more than something that’s been studied and proven safe?” she asks.

Survey reports on who uses cannabis, why, and how

The new Harvard-led survey, published in the journal Menopause, looked at patterns of cannabis use in 131 women in perimenopause — the often years-long stretch before periods cease — along with 127 women who had passed through menopause. Participants were recruited through online postings on social media sites and an online recruitment platform. Nearly all survey respondents were white and most were middle-class, according to income reporting.

The vast majority (86%) were current cannabis users. Participants were split on whether they used cannabis for medical reasons, recreational purposes, or both. Nearly 79% endorsed it to alleviate menopause-related symptoms. Of those, 67% said cannabis helps with sleep disturbance, while 46% reported it helps improve mood and anxiety.

Perimenopausal women reported worse menopausal symptoms than their postmenopausal peers, as well as greater cannabis use to address their symptoms. More than 84% of participants reported smoking cannabis, while 78% consumed marijuana edibles, and nearly 53% used vaping oils.

One glaring limitation of the analysis is its self-selected group of participants, which lacked diversity and might skew results. But Dr. Hirsch wasn’t surprised by the high proportion reporting regular cannabis use. “I wouldn’t be surprised if those numbers reflect the broader population,” she says.

How might cannabis help menopause symptoms?

It makes sense that midlife women reported cannabis improves anxiety, mood, and sleep, Dr. Hirsch says. The drug likely helps all of these symptoms by “dimming the prefrontal cortex, the decision-making part of our brain.”

For many women, anxiety spikes during perimenopause, she notes. Common stressors during that time, such as aging parents or an emptying nest, add to the effects of dipping hormones. “It’s that feeling of, ‘I can’t turn my brain off.’ It’s really disturbing because they get in bed and can’t fall asleep, so they’re more tired, moody, and cranky the next day,” she explains. Dimming the prefrontal cortex enables people to calm down.

Hot flashes, often cited as the most common menopause symptom, did not improve as much from cannabis use, according to survey respondents. That too makes sense, Dr. Hirsch says, because the hypothalamus — the brain region considered the body’s thermostat — isn’t believed to be significantly affected by the drug.

No research yet on long-term effects

Given a lack of clinical trials objectively testing the effectiveness and safety of cannabis to manage menopause symptoms, more research is clearly needed.

“If people are finding relief from cannabis, great. But is it safe? We think so, but we don’t know,” she says. “There are no studies of middle-aged women using cannabis for 10 years, for as long as menopause symptoms often last. Are there going to be long-term effects on memory? On lung function? We don’t know.”

About the Author

Maureen Salamon, Executive Editor, Harvard Women's Health Watch

Maureen Salamon is executive editor of Harvard Women’s Health Watch. She began her career as a newspaper reporter and later covered health and medicine for a wide variety of websites, magazines, and hospitals. Her work has … See Full Bio View all posts by Maureen Salamon