Coronary CT angiography with iterative reconstruction in early triage of patients with acute chest pain

BackgroundPatients who present to the emergency department (ED) complaining of acute chest pain are of clinical concern because a small percentage will have acute coronary syndrome (ACS). The American College of Cardiology (ACC) and the American Heart Association (AHA) recommend hospitalization for patients with a low-to-intermediate risk of ACS who have initial negative ECG and enzyme test results. A negative coronary CT angiography (CCTA) during the triage has a very high negative predictive value for ruling out ACS decreasing the length of hospital stay. Recent techniques e.g. ASiR in CCTA should be used to decrease the radiation dose as low as possible.ObjectiveThe aim of this study is to evaluate the role of low radiation dose CCTA with ASiR in triage of low-risk patients with acute chest pain in emergency department. A negative CCTA early in the workup may enable a shorter length of stay.Subjects and methodsWe studied 54 selected patients (55.6% men; mean age 48 ± 6 years) with chest pain who were awaiting hospital admission to rule out ACS despite the absence of diagnostic ECG changes and normal cardiac enzymes on ED presentation. Patients underwent CCTA before hospital admission. Afterward, patients received standard clinical care (SCC). ER physicians involved in the patient’s care were blinded to the results of CCTA. An expert panel established the presence or absence of ACS based on AHA guidelines. The CCTA images were evaluated for the presence of significant coronary artery stenosis (diameter reduction >50%) and were used to make a triage decision.ResultsFour patients (7.4%) with chest pain had at least one significant coronary stenosis on CCTA (sensitivity 100%, specificity 96%, accuracy 96.3%, positive predictive value (PPV) 66.7% and negative predictive value (NPV) 100%). Significant coronary stenosis was excluded in 48 of the 54 patients by CCTA (88.9%), potentially saving about 71.6% of unnecessary hospital admission hours.ConclusionCCTA based detection of significant coronary stenosis has potential role to decrease the length of hospital stay, without reducing appropriate patient care, in low risk patients with acute chest pain. CCTA should be done with lowest radiation possible using recent techniques.