Coronary Computed Tomography Angiography Versus Radionuclide Myocardial Perfusion Imaging in Patients With Chest Pain Admitted to Telemetry: A Randomized Trial

Abstract

Background: The role of coronary computed tomography angiography (CCTA) in the management of symptomatic patients suspected of having coronary artery disease is expanding. However, prospective intermediate-term outcomes are lacking.

Objective: To compare CCTA with conventional noninvasive testing.

Design: Randomized, controlled comparative effectiveness trial. (ClinicalTrials.gov: NCT00705458).

Setting: Telemetry-monitored wards of an inner-city medical center.

Patients: 400 patients with acute chest pain (mean age, 57 years); 63% women; 54% Hispanic and 37% African-American; and low socioeconomic status.

Intervention: CCTA or radionuclide stress myocardial perfusion imaging (MPI).

Measurements: The primary outcome was cardiac catheterization not leading to revascularization within 1 year. Secondary outcomes included length of stay, resource utilization, and patient experience. Safety outcomes included death, major cardiovascular events, and radiation exposure.

Results: Thirty (15%) patients who had CCTA and 32 (16%) who had MPI underwent cardiac catheterization within 1 year. Fifteen (7.5%) and 20 (10%) of these patients, respectively, did not undergo revascularization (difference, -2.5 percentage points [95% CI, -8.6 to 3.5 percentage points]; hazard ratio, 0.77 [CI, 0.40 to 1.49]; P = 0.44). Median length of stay was 28.9 hours for the CCTA group and 30.4 hours for the MPI group (P = 0.057). Median follow-up was 40.4 months. For the CCTA and MPI groups, the incidence of death (0.5% versus 3%; P = 0.12), nonfatal cardiovascular events (4.5% versus 4.5%), rehospitalization (43% versus 49%), emergency department visit (63% versus 58%), and outpatient cardiology visit (23% versus 21%) did not differ. Long-term, all-cause radiation exposure was lower for the CCTA group (24 versus 29 mSv; P < 0.001). More patients in the CCTA group graded their experience favorably (P = 0.001) and would undergo the examination again (P = 0.003).

Limitation: This was a single-site study, and the primary outcome depended on clinical management decisions.

Conclusion: The CCTA and MPI groups did not significantly differ in outcomes or resource utilization over 40 months. Compared with MPI, CCTA was associated with less radiation exposure and with a more positive patient experience.

Primary funding source: American Heart Association.

Figure 1

CONSORT Flow Diagram. Footnote: CAD, coronary artery disease; CT, coronary computed tomography angiography; ED, emergency department; ICD, implanted cardioverter/defibrillator; MI, myocardial infarction; MPI, radionuclide stress myocardial perfusion imaging. *Recent imaging means coronary CT, MPI or cardiac catheterization within 6 months †MD preference means the managing physician had already chosen a non-invasive imaging modality and would not allow the patient to be randomized. ‡Other reasons for exclusion are listed in Supplementary Online Table 1. CT was not performed in 13 patients because of patient refusal (9), physician decision (1), technical difficulty (1) and safety concerns (2); of these, 7 patients received MPI. MPI was not performed in 11 patients because of patient refusal (6), physician decision (4), and technical difficulty (1); of these, 0 patients received CT. During hospitalization, 6 patients that received initial CT had additional MPI and 4 patients that received initial MPI underwent additional CT. Lost patients could not be contacted by any means including identification and inquiry of any treating physicians. All patients were included in the primary analysis (Cox proportional hazards model).