Coronary CTA for Acute Chest Pain in the Emergency Department: Comparison of 64–Detector-Row Single-Source and Third-Generation Dual-Source Scanners

BACKGROUND. When coronary CTA is performed in the emergency department (ED), the use of a contemporary scanner with improved temporal resolution may eliminate the need to administer β-blockers for heart rate (HR) control, thereby expediting workup. OBJECTIVE. The purpose of this study was to compare ED length of stay (LOS), image quality, frequency of nondiagnostic examinations, and other clinical outcomes between patients undergoing coronary CTA in the ED on a single-source CT (SSCT) scanner with HR control versus on a dual-source CT (DSCT) scanner without HR control. METHODS. This retrospective study included 509 patients (283 men, 226 women; mean age, 52.1 ± 15.1 [SD] years) at low to intermediate risk for acute coronary syndrome who underwent coronary CTA for acute chest pain during off-hours in a single ED from March 1, 2020, to April 25, 2022. A total of 205 patients initially underwent CTA using a 64-detector-row SSCT scanner with HR control (oral β-blocker administration if HR was > 65 beats/min); after scanner replacement on April 26, 2021, 304 patients underwent CTA using a third-generation DSCT without HR control. Groups were compared in terms of ED LOS and CT completion time (defined as time from ordering CTA to completion of acquisition) using propensity score matching and additional endpoints including image quality and nondiagnostic examinations based on radiology reports. RESULTS. The DSCT group, compared with the SSCT group, showed no significant difference in median ED LOS (505 vs 457 minutes, respectively; p = .37) but showed shorter median CT completion time (95 vs 117 minutes, p < .001); on the basis of a mediation analysis, 89% of the reduction in CT completion time for DSCT was attributed to the absence of HR control. The DSCT group, compared with the SSCT group, showed higher frequency of examinations with good or excellent image quality (87.8% vs 60.0%, p < .001) and lower frequency of nondiagnostic examinations (1.6% vs 6.3%, p = .01) but showed no significant difference in frequencies of emergent cardiology consultation, invasive angiography, ED disposition, or coronary revascularization (all p > .05). No patient in either group experienced 30-day all-cause mortality or a major adverse cardiovascular event. CONCLUSION. The use of a DSCT scanner for coronary CTA can eliminate the need for β-blocker administration for HR control while decreasing nondiagnostic examinations. CLINICAL IMPACT. A DSCT scanner can expedite clinical processes in the ED.