Routine use of Coronary CTA Cuts Down on ED Patients Admitted for Chest Pain

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Compared with standard evaluation, which often includes nothing but observation and discharge, use of coronary computed tomographic angiography (CTA) in patients presenting to the emergency department (ED) with chest pain significantly reduces the rate of hospital admission. According to results of a study scheduled to be published online May 14, 2013, ahead of print in the Journal of the American College of Cardiology, routine coronary CTA use also reduces ED or hospital recidivism and invasive angiography without subsequent revascularization.

Researchers led by Michael Poon, MD, of Stony Brook University Medical Center (Stony Brook, NY), conducted a retrospective analysis of 1,788 risk-matched patients who presented to their ED with chest pain between January 2008 and April 2010. Coronary CTA was introduced at their center in January 2009 as an alternative to standard evaluation and was available 12 hours a day, 7 days per week. Patients were assessed by standard evaluation before introduction of coronary CTA and by either standard evaluation or coronary CTA thereafter at the physician’s discretion.

CTA Lowers Admissions, Returns to ED

The primary endpoint of hospital admission rate was lower with coronary CTA compared with standard evaluation (14% vs. 40%; P ≤ 0.0001). Furthermore, patients examined by standard evaluation were more likely to be admitted, return to the ED within 30 days for recurrent chest pain, and undergo coronary angiography without revascularization compared with coronary CTA (table 1).

Table 1. Standard Evaluation vs. Coronary CTA


OR (95% CI)

P Value

Admission Rate

5.53 (3.8-8.0)

≤ 0.001

Return to ED for Chest Pain

5.06 (1.3-20.3)


Angiography Only

7.17 (2.5-20.6)

≤ 0.001

Coronary CTA had the most significant impact on length of stay during times of peak ED volume—12:00 pm to 8:00 pm. During these times, the mean length of stay was 7.7 hours for the coronary CTA group vs. 11.5 hours for the standard evaluation group.

No cardiac deaths occurred in either group, and the odds of acute MI were similar between coronary CTA and standard evaluation (OR 4.26; 95% CI 0.3-71.4; P ≤ 0.313).

Fewer coronary CTA patients than standard evaluation patients returned to the hospital within 30 days of the index admission (1.3% vs. 3.6%; P = 0.002). However, after risk adjustment, the difference was no longer significant (OR 8.53; 95% CI 0.4-179.9; P = 0.168).

Frustration Fueled Research Effort

In a telephone interview with TCTMD, Dr. Poon said the findings agree with those of the 3 randomized trials conducted to date but add a more ‘real-world’ sense of how patients and hospitals can benefit from the routine use of coronary CTA.

“The randomized trials have shown that coronary CTA is cost efficient compared with standard of care but the standard of care approach for the most part in these studies was not realistic,” Dr. Poon observed. “We all know that what happens in the real world with these patients in terms of evaluation is for the most part, nothing. They go home. That’s it.”

Dr. Poon said part of the impetus for the study was frustration by the lack of widespread coronary CTA use, adding that he has heard colleagues describe using the method in randomized trials only to return to standard evaluation after trial completion even after seeing significant enhancements in care.

“What is the point of the randomized trials proving that it’s superior if no one is using it afterward? This is something you have to continue to work on and perfect just like anything else,” Dr. Poon said.

Radiation Doses Lowered

While a variety of issues have led to the limited use of coronary CTA for chest pain patients in the ED, the most controversial and criticized aspect is the radiation dose. In some randomized trials, including ROMICAT II, the radiation doses “were insanely high,” at a cumulative dose of 14.3 ± 10.9 mSv in the coronary CTA arm, Dr. Poon reported. In contrast, the 5.88 mSv mean dose in the current study is proof, he said, that with routine use, even in a busy setting, the radiation dose can be kept low.

“This has been a big problem in the randomized trials and you have people constantly saying that coronary CTA carries a high radiation exposure and it’s just not true. It doesn’t have to be the case if it is being performed correctly,” Dr. Poon noted. In fact, he has begun reaching out to nearby hospitals to teach them proper use of coronary CTA.

“I really hope that this paper will encourage others to adopt it,” Dr. Poon said. “You cannot do nothing for these patients. This paper is timely because we need ways that are safe and cost-effective more than ever to get patients in and out quickly without taking a chance and letting them go home and saying, ‘well, they’ll be okay.’”

Experience Shows

In a telephone interview with TCTMD, Matthew J. Budoff, MD, of Harbor-UCLA Medical Center (Torrance, CA), said the study “certainly adds strength to the observation that CT angiography is at least as effective, if not more so, than standard of care imaging and is very concordant with all of the other studies so far.”

He noted that the inclusion of admission data in this study improves the clinical relevance because previous studies, including the randomized trials, have looked primarily at time to diagnosis or time to discharge.

Echoing Dr. Poon, Dr. Budoff said randomized trials are not always conducted at centers that are the most up-to-date. “It might be a great clinical trial center but have very little experience with coronary CTA,” he observed. “This paper is showing you how an experienced group is using it on a daily basis and getting good results. I believe as we see more and more ongoing experience from groups such as this one we will see more and more separation of the curves from standard of care … and will be able to see the evolution of both the technology and the users.”

In fact, although there was no difference between standard evaluation and coronary CTA at 30 days for cardiac death and acute MI in this study, Dr. Poon reported that unpublished 6-month data show “a significant reduction in MACE events with coronary CTA compared with standard of care.”

Study Details 

Patients without ST-segment elevation, ST-depression of ≥ 1 mm, or positive cardiac troponin I (> 0.04 pg/mL) were assessed by standard evaluation before coronary CTA introduction and by either standard evaluation or CTA after introduction based on ED physician discretion.


Poon M, Cortegiano M, Abramowicz AJ, et al. Routine coronary computed tomographic angiography reduces unnecessary hospital admissions, length of stay, recidivism rates, and invasive coronary angiography in the emergency department triage of chest pain. J Am Coll Cardiol. 2013;Epub ahead of print.



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  • The study contains no statement regarding conflicts of interest for Dr. Poon.
  • Dr. Budoff reports no relevant conflicts of interest.