NewYork-Presbyterian Healthcare System To Institute Cardiac Protocol
Jun 16, 2003
Each year more than 5 million people go to emergency rooms with complaints of chest pain. Doctors assess which of them is having a heart attack through electrocardiograms (EKGs) and blood tests so they can be treated quickly.
But it is unclear what should be done for the patients with chest pain who are not having a heart attack. Some patients' chest pain can be traced to anxiety or lifting something heavy, but chest pain could be a sign of heart disease.
Now, a study by physicians and scientists at Columbia University College of Physicians Surgeons and NewYork-Presbyterian Hospital/Columbia University Medical Center finds that patients with chest pain who undergo a stress test have a significantly lower death rate than those who do not take a stress test. The results of the study are published in the June 15 issue of the American Journal of Cardiology.
During three months following a chest pain episode, patients who did not take a stress test combined with imaging of the blood flow to the heart were six times more likely to die than those who took the test (3% vs. 0.5%), the study found.
"The study demonstrates that stress tests can identify patients with underlying coronary artery disease," says Dr. Steven R. Bergmann, Margaret Milliken Hatch Professor of Medicine and professor of radiology at Columbia University College of Physicians Surgeons, director of nuclear cardiology at NewYork-Presbyterian Hospital/Columbia and the study's co-principal investigator. "Patients who appear normal following EKGs and blood tests are usually sent home, missing an opportunity to diagnose and treat underlying cardiac problems."
A stress test is given to show deficiencies in blood flow in the heart. The test requires that a patient either walk on a treadmill or take medications that simulate the effect of exercise on the heart. A small amount of a radioactive substance is given at peak stress to measure maximum blood flow to the heart. By contrast, an EKG is administered when a patient is at rest.
"Because some blood flow problems only show up when the heart's workload is increased, stress tests are a better means to measure cardiac abnormalities than EKGs," says Dr. LeRoy E. Rabbani, associate professor of clinical medicine at Columbia University College of Physicians Surgeons, director of the cardiac intensive care unit and the chest pain program at NewYork-Presbyterian Hospital/Columbia and the study's co-principal investigator.
The study tracked 1,195 chest pain patients that showed EKG and blood tests in the normal range for three months. While a stress test was recommended for all patients meeting the criteria, each medical team was allowed to decide if stress tests were necessary. Of the patients studied, 43 percent received a stress test.
Of patients taking the imaging stress test, 63 percent were shown to have no evidence of heart disease. Four percent returned to the hospital but none of them returned with a heart attack. Abnormal stress test results were detected in 37 percent of those tested, indicating evidence of coronary artery disease. Of those, 19 percent returned to the hospital and 3 percent experienced a heart attack.
By contrast, of the 630 patients who did not receive a stress test, the return rate was nearly 15 percent and the rate of return with a heart attack was 2 percent.
The authors hope to continue their research and follow patients for longer periods of time. "We'd like to examine whether after ruling out a heart attack, patients could go home and return at a later date for a stress test," says Dr. Bergmann.
Based on the early findings of this study, a chest pain protocol, which includes recommendations for stress tests, was put in place at Columbia University Medical Center, NewYork Weill Cornell Medical Center and the Allen Pavilion at NewYork-Presbyterian Hospital. The NewYork-Presbyterian Healthcare System is working with the cardiac leadership of its 31 general acute hospital member institutions to further the implementation of these protocols throughout the system.