WEDNESDAY, Nov. 15, 2017 (HealthDay News) -- ER doctors frequently use pricey but unnecessary tests to determine whether people with chest pain are having a heart attack, a new study reveals.
Results show that patients don't do any better when CT scans or treadmill stress tests are tacked onto the standard battery of diagnostic tests for chest pain patients.
"You don't need all this imaging just to rule out the diagnosis of a heart attack," said senior researcher Dr. David Brown, a professor with Washington University School of Medicine in St. Louis. "They provide no additional value."
Around 10 million Americans land in the emergency room each year with chest pain that could indicate a heart attack, the researchers said.
Doctors typically evaluate heart attack using blood tests, an EKG, a medical history and a physical examination, Brown said. The blood test looks for troponin, a protein released by the heart when it has been damaged.
But many patients also receive a CT scan to see if arteries that deliver blood to the heart are blocked, or a heart stress test to see if their physical ability is impaired, the study authors said.
"The predominant goal in patients that show up in the emergency department with chest pain is to make sure they're not having a heart attack, because no one wants to send home a patient in the midst of a heart attack," Brown said.
To see whether CT scans or stress tests added anything to the accuracy of a diagnosis, Brown and his team randomly assigned 1,000 chest pain patients at nine U.S. hospitals to either receive the extra testing or undergo the usual panel of heart attack tests. About 88 percent of patients received the extra tests.
Patients who didn't get the extra testing got out of the hospital sooner, with an average stay of 20 hours compared with 28 hours for those who also underwent CT scans and stress tests, according to the report.
During the month following their ER visit, no significant difference appeared between the two groups in terms of who needed heart bypass surgery or a procedure to reopen a blocked artery, the findings showed.
There also was no difference between the two groups in terms of who later returned to the ER or suffered a major cardiac event, such as a heart attack, Brown said.
On the other hand, patients who received extra testing racked up $500 more in hospital bills during their ER visit. They also were more likely to get follow-up tests within the next month, adding another $300 in health care costs, the researchers said.
The problem is that the CT scans and stress tests are not meant to be used to diagnose a heart attack, Brown explained. Those tests help determine whether a person has heart disease -- plaque buildup in their arteries that is damaging their heart health.
"Even if you have a diagnosis of coronary disease, it doesn't mean you're having a heart attack," Brown said. "That diagnosis is not an immediately life-threatening diagnosis."
Studies like this have led ERs and chest pain centers across the United States to question their diagnostic processes, said Dr. Richard Chazal, immediate past president of the American College of Cardiology. He is also medical director of the Lee Health Heart and Vascular Institute in Fort Myers, Fla.
Doctors likely are tempted to use the extra tests as a form of "defensive medicine" that reduces their risk of a malpractice suit, Brown and Chazal said.
"If I miss one heart attack, I'm going to be sued," Chazal said. "Even if the patient has a low risk, I still have a liability. Physicians are fearful of this. You could do the right thing for the right reasons, and still find yourself in trouble."
The need for these extra tests will be further diminished by new high-precision troponin blood tests that are headed for the U.S. market, Chazal added.
"A negative high-sensitive troponin test shows the prognosis is extremely good regardless of what else you do," Chazal said. "It puts one in a position to discharge and postpone workup."
However, Chazal said he would like to see longer-term follow-up in patients from this study, to see if problems crop up beyond the month following their ER visit.
Chazal also was troubled by the percentage of study patients who wound up back in the ER during follow-up. Even though the number was not statistically significant, 6 percent of those who underwent standard testing returned to the ER later in the month, compared with about 3 percent of patients who got the extra tests.
Although chest pain patients don't need these extra tests in the ER, both Brown and Chazal said they should discuss the tests with their family doctor after the immediate danger has passed, to see if they have heart disease.
"We think those patients should be sent home with instructions to follow up with their primary care doctor to discuss this event, and the primary care doctor should then decide what follow-up testing should be performed," Brown said.
Chazal agreed that these patients "still need a follow-up visit with a qualified physician to determine if they are at increased long-term risk. That doesn't necessarily mean that needs to take up time in the emergency department or the hospital, but it also doesn't mean they can say, 'I have no problem and don't have to worry about it.' "
The study was published online Nov. 14 in the journal JAMA Internal Medicine, to coincide with a planned presentation of the findings at the American Heart Association's annual meeting, in Anaheim, Calif.
For more on heart attacks, visit the American Heart Association.