Coronary computed tomographic angiography to evaluate acute chest pain reduces hospital admissions

Hospital admissions at Stony Brook University Medical Center on Long Island were significantly reduced when using coronary computed tomographic angiography (CCTA) to evaluate patients presenting in the emergency department (ED) with acute chest pain (ACP), according to research results presented during a scientific session at the American College of Cardiology's 60th Annual Scientific Session and Expo in New Orleans on April 3. Michael Poon, M.D., Professor of Radiology and Medicine, Stony Brook University School of Medicine, and Director of the Center for Advanced Cardiovascular Imaging at SBUMC, presented the data, which stems from studies conducted at Stony Brook that applied CCTA with a 64-slice CT in evaluating the ACP patients.

CCTA is a noninvasive heart imaging test that helps determine if fatty or calcium deposits/plaques have narrowed a patient's coronary arteries. CCTA is a special type of x-ray examination that combines x-ray equipment with sophisticated computer hardware and software to produce high quality and diagnostic images or pictures of the heart.

"Our data showed that CCTA saved more than 30 percent of unnecessary admissions each year compared to stress testing," says Dr. Poon. "Without CCTA, approximately 50 percent of the ED chest pain patients were admitted. With CCTA, less than 15 percent were admitted. Each unnecessary admission costs the hospital approximately $5,000. Thus for every 250 patients, the hospital saved approximately $1.3 million," he explains.

"The nation's attention has been drawn to the costs of healthcare," says Steven L. Strongwater, M.D., CEO, Stony Brook University Hospital. "Dr. Poon's use of technology to improve diagnostic accuracy, while at the same time reducing the costs of healthcare through avoidable hospitalizations, is exactly the kind of innovation that reduces costs without compromising quality of care. We are very proud of Dr. Poon's work, which is also exemplary of the type of innovation sought by the healthcare Accountability Act."

In addition to avoiding many unnecessary hospital admissions, Dr. Poon points out that the study results indicated that with use of CCTA in the ED, physicians could evaluate more patients with ACP and streamline the care of this group of patients much more efficiently.

"Our clinical study results showed that we could safely discharge low-to-intermediate risk patients with acute chest pain from the ED following a negative CCTA without any adverse outcome for six months following the ED visit," says Dr. Poon. "Additionally, we are able to identify those patients with early coronary artery disease and recommend early medical intervention with the assistance of their primary care physicians."

Dr. Poon says that the study is the largest financial impact analysis to date on the use of CCTA. The study included the first 1,089 CCTAs performed for the evaluation of ACP in an ED with 90,000 visits per year.

Of the 1089 CCTA performed, 731 (67%) were normal, 251 (23 %) nonobstructive, 26 (2%) obstructive, and 81 (7%) nondiagnostic. Of those ACP patients with obstructive or nondiagnostic CCTA, 72 (67%) were admitted whereas only 89 (9%) of the normal or nonobstructive cases were admitted. Of those ACP patients who did not have CCTA as an initial test, 2283 (50%) were admitted and 792 (35%) were later discharged without specific cardiac diagnosis. Conversely, only 43 (27%) of those who had CCTA initially were discharged without specific cardiac diagnosis.

Dr. Poon contends that CCTA is a safe, cost-saving, and resource-efficient imaging modality for the daily evaluation of acute chest pain in the emergency centers of hospitals.

"Conventional diagnostic tests using treadmill exercise often diagnose obstructive coronary artery disease when it is too late to treat medically or through lifestyle modification," Dr. Poon explains. "Furthermore, conventional diagnostic tests often give false positive test results, leading to unnecessary invasive procedures and interventions, including coronary stenting and surgery."

The Journal of Thoracic Imaging reported in the August 2010 issue that technical development has substantially improved diagnostic performance of CCTA. Clinical evidence supports the significant role of CCTA in an increasing number of scenarios, including the detection of coronary disease in symptomatic patients who are at intermediate risk and the evaluation of coronary revascularization procedures.

"We strongly believe that we have developed a robust, revolutionary and state-of-the-art methodology for the evaluation of acute chest pain in the ED, and this can be done seven days a week with excellent clinical outcome and is cost-effective," says Dr. Poon.

Dr. Poon and colleagues plan to conduct more clinical research in the next few years to further evaluate the financial and clinical outcome benefits and the comparative effectiveness of various CT systems, innovative CT diagnostic techniques, and radiation dose saving techniques.

Ongoing studies will involve the use of a 320-slice CT that was installed in the ED in 2010, one the most advanced CT instruments in the world. SBUMC is the only institution on Long Island with a 320-slice CT. Also significant, he explains, is that the new 320-slice CT may allow significant reduction of radiation and contrast doses that are normally required to perform CCTA and further increase the throughput of the ED.