July 24, 2014
News Review From Harvard Medical School -- Taking Pulse May Help Track Stroke Risk
People who have had strokes and their family members can help detect an increased risk of a second stroke, a new study suggests. The technique used was a simple one: checking the pulse. The study included 256 people. Each person had a prior stroke caused by a blood clot. Stroke survivors and close family members were trained to detect atrial fibrillation by taking the pulse. This irregular heart rhythm can increase the risk of blood clots forming in the heart. A clot that travels to the brain may cause a stroke. All of the stroke survivors received EKG tests. They found that 57 people had atrial fibrillation. The EKG results were compared with pulse readings performed by stroke survivors, relatives and health professionals. Pulse readings done by patients correctly detected 54% of the cases of atrial fibrillation. Relatives detected 77% and health professionals 97%. The groups were 93% to 96% accurate in identifying a normal rhythm. The journal Neurology published the study. HealthDay News wrote about it July 23.
By Robert H. Shmerling, M.D.
Harvard Medical School
What Is the Doctor's Reaction?
Imagine a free, painless test you can do yourself in 30 seconds, a test that can tell you whether you're at risk for stroke.
There is such a test. It's called checking your pulse. And it's the subject of a study just published in the medical journal Neurology.
In this study, 256 people who had suffered a stroke were taught how to monitor their own pulse for an irregular (abnormal) rhythm. Some family members were also trained.
Why is it important to detect an irregular rhythm? The rhythm of your pulse reflects the rhythm of your heart. And a common abnormal heart rhythm, called atrial fibrillation, is a major, treatable factor that increases the risk of stroke.
This new study compared patients or their relatives with health-care professionals. The goal was to see how well each group could detect an irregular pulse. EKG recordings confirmed whether an abnormal heart rhythm was occurring. After receiving training:
- Patients were able to detect an abnormal pulse in 54% of cases when an abnormal rhythm was present. Relatives detected 77% of cases. This compares with 97% of health-care professionals.
- Patients accurately identified a normal pulse in 96% of cases. The rate was 93% for family members and 94% for health-care professionals.
Checking for an irregular heart rhythm after stroke is nothing new. It's a routine part of the evaluation of any stroke patient. This usually includes recordings of the heart's electrical activity by EKG or by monitoring over many hours or days. One recent study found that an implantable recording device was better than standard methods for detecting atrial fibrillation in people with recent stroke.
But training people who have had strokes or their family members to monitor the pulse is a novel, low-tech approach. Based on this study, it also seems reasonably accurate.
What Changes Can I Make Now?
If you have had a stroke in the past, talk to your doctor about the results of this research. Together, you can decide whether you should learn to monitor your pulse.
Know the factors that increase the risk of stroke. You can take action to reduce some of these risks. Here's what you can do:
- Smoking -- Make quitting a priority.
- A "high risk" cholesterol profile, such as high total and LDL cholesterol -- Reduce high numbers through diet, exercise and, when necessary, medicines. These steps can reduce your risk of heart and blood vessel disease, including stroke.
- High blood pressure (hypertension) -- Medicines to lower blood pressure can reduce stroke risk.
- Diabetes -- Treatments to control blood sugar and combat blood vessel complications may lessen stroke risk.
- Atrial fibrillation -- When the heart is beating irregularly, blood clots can form. Clots can travel from the heart to the brain, causing a stroke. A blood thinner, such as warfarin (Coumadin), can reduce stroke risk by preventing clots from forming.
- A diseased carotid artery -- Plaque deposits (atherosclerosis) involving this major artery in the neck can lead to stroke. Surgery to open it up can lessen stroke risk.
Changes in what you eat also may reduce stroke risk. Aim for a diet that is high in fruits and vegetables and low in saturated and trans fats. Try to include several servings of fish per week.
Low-dose aspirin also may be recommended for those with prior stroke or multiple risk factors for stroke, such as those above.
A strong family history of heart and blood vessel disease also increases the risk of stroke. Of course, it can't be changed, but a family history of stroke makes it even more important to take steps to modify the other risk factors.
What Can I Expect Looking to the Future?
If other researchers confirm the findings of this study, taking your pulse on a regular basis after stroke could become routine. It could even become commonplace for people who haven't yet had a stroke, especially for those with multiple risk factors for stroke.
At a time when expensive and invasive medical testing is increasingly common, it's important not to overlook simpler options that may be effective. Involving patients in their own monitoring is one such approach. And when patients are unable to monitor themselves, family members may be recruited to do so.
Self-monitoring may take advantage of technology, such as the use of an activity-tracking bracelet. Or patients may simply be taught to check the rhythm of their own pulses. You can expect both approaches to become more common in the future.