News Review From Harvard Medical School -- CT Shows Mixed Results for Chest Pain
If you have chest pain, but aren't having a heart attack, an advanced CT scan can help get you out of the emergency room sooner, a study finds. But it might not be worth the extra radiation and later tests. The study included 1,000 people with chest pain. All had electrocardiograms and blood tests that suggested a heart attack was unlikely. Then they were randomly divided into 2 groups. People in one group got standard tests, such as a stress test. The others got a type of CT scan that gives a detailed view of arteries around the heart. People spent an average of 23 hours in the hospital with the CT scans and 30 hours with standard tests. About 47% were sent home after the CT scans, compared with 12% who had standard tests. The others were admitted. But those in the CT group received 3 times as much radiation as the standard-care group. They also were more likely to have expensive tests later, so their total testing costs were a bit higher. The Journal of the American Medical Association published the study. The Associated Press wrote about it July 26.
By Robert H. Shmerling, M.D.
Harvard Medical School
What Is the Doctor's Reaction?
It's amazing how often people come to emergency rooms with chest pain. In the United States, it's about 6 million times each year.
A heart attack is the most common concern. So emergency room doctors have a big challenge. How can they tell whether a person with chest pain is one of the 5% to 10% who are actually having a heart attack?
Doctors do a standard evaluation. This includes:
- Detailed questions about symptoms
- A physical examination
- Tests to look for evidence of heart injury or strain, such as:
- An electrocardiogram (EKG)
- Blood tests
- A stress test
Some people are sent home without all of these tests. For example, a young, healthy person with no risk factors (such as smoking) has a very low risk of heart attack. But, for the rest, the tests are common procedure. This can take hours. Some people stay overnight.
This new study assesses whether another test can speed things up. It's a type of CT scan called coronary computed tomographic angiography (CCTA). The test provides images of the arteries around the heart.
The New England Journal of Medicine published results of the new study. It included 1,000 people, ages 40 to 74, who had chest pain. All had EKGs and blood tests that did not indicate a heart attack. Half were randomly assigned to have CCTA as well.
The researchers found that:
- Only 8% of study subjects had an acute coronary syndrome. This means blood flow to the heart is blocked. The term includes a heart attack, if the blockage has already damaged heart muscle.
- Among those admitted to the hospital, the ones assigned to have a CCTA were discharged a bit sooner (by 7.6 hours).
- About 47% of people assigned to CCTA (47%) went home without hospital admission. This compares with 12% of those assigned to standard care alone.
These results do suggest CCTA may be helpful. But there were other results to consider:
- People assigned to CCTA were exposed to more radiation.
- They also had more tests after the emergency room visit. The cost of all tests combined was slightly higher in the CCTA group.
So, the results were mixed. Is the improved chance of having no hospital stay or a slightly shorter stay worth the added radiation, slightly higher cost and increased downstream testing? I'm not convinced it is.
An editorial published with this research suggests another approach. Every person in this study had blood tests and EKG results that were reassuring. So they were already at very low risk of heart attack. The editorial says it may not have been necessary to do any other tests. Maybe we should change standard care, and send more people home with no further tests at all. It's a good point!
Then again, it's a challenge to strike the right balance between avoiding tests you don't need and making sure you don't miss something important.
What Changes Can I Make Now?
We need more research to figure out the best way to evaluate chest pain in the emergency room. In the meantime, you can make changes to reduce the chance you'll ever have a heart attack. Here's what you can do:
- Don't smoke.
- Keep your cholesterol and blood pressure in a good range. Loss of excess weight, exercise and medicines can help.
- Improve your diet. Choose a well-balanced diet that's low in total, saturated and trans fats. The DASH diet limits salt intake and encourages eating more fruits, vegetables and low-fat dairy products. This diet may reduce your risk of high blood pressure, a risk factor for heart disease.
- Reduce your risk of diabetes. Keep your weight in a healthy range. If you already have diabetes, weight loss, exercise and medicines can reduce your risk of further problems, such as heart disease.
- Exercise more. This can reduce the chances that you'll develop high cholesterol, high blood pressure or diabetes.
If you already have coronary artery disease, you can take further steps to prevent a heart attack.
- Take your medicines as prescribed, and follow up regularly with your doctors.
- Let your doctor know of any symptoms you have, such as chest pain or shortness of breath.
- Talk to your doctor about whether you should take aspirin and/or take nitroglycerin for chest pain.
Have a plan in place in case you have lasting chest pain that could be caused by a heart attack. For example, know where the closest emergency room is from your home or work.
What Can I Expect Looking to the Future?
There's much we could do better to treat chest pain in emergency rooms. Future research should help to sort out:
- Which patients can safely go home without tests or hospital admission
- Which tests are the safest and most cost-effective
- Whether there is a role for CCTA in evaluating chest pain
It's clear that some people receive care in emergency rooms that could be provided just as well in their doctors' office or even at home. Others delay seeking care, with tragic results. I hope we'll soon do a better job getting people to the emergency room at the right time and reducing the number who don't need to be there.