Author + information
- Milena Henzlova,
- John Savino,
- Elliot J. Levine,
- Lori Croft,
- Andrew Einstein,
- Luke Hermann and
- William Duvall
Recent studies have compared CTA to stress testing and MPI using older Na-I SPECT cameras and traditional rest-stress protocols. We compared CTA to stress testing with modern SPECT MPI using high-efficiency CZT cameras and stress-first protocols in an ED population.
In a retrospective, non-randomized study all patients who underwent CTA or stress testing [exercise treadmill testing (ETT) or Tc-99m sestamibi SPECT MPI] as part of their ED assessment in 2010-2011 driven by ED attending preference and equipment availability were evaluated for their disposition from the ED (admission vs discharge, length of time to disposition), subsequent visits to the ED and diagnostic testing (within 3 months), and radiation exposure. CTA was performed on a 64-slice scanner (GE Lightspeed VCT) and MPI was performed on a CZT SPECT camera (GE Discovery 530c). Data was obtained from prospectively acquired electronic medical records and effective doses were calculated from published conversion factors.
Over the 2 years, 1,458 patients underwent testing in the ED with 192 CTA's and 1,266 stress tests (327 ETT's and 939 MPI's). The CTA patients were a lower risk cohort based on age, risk factors, and known heart disease. In the MPI group, 708 (75%) underwent stress-only imaging with 853 (91%) imaged on a CZT camera. Non-significantly more patients were discharged directly from the ED in the stress testing group than the CTA group (82% vs 73%, p = 0.28) but their time to disposition was significantly longer (20.5 ± 7 vs 11.0 ± 5 hrs, p < 0.0001). There were more cardiac return visits to the ED with CTA than stress testing (47% vs 10%, p = 0.0002), and more follow-up studies in the CTA group (14% vs 7%, p = 0.001). The mean effective dose of 13.5 ± 9 mSv for the CTA group was higher (p < 0.0001) than 5.0 ± 4 mSv for the stress-testing group (ETT and MPI) and 6.4 ± 3 mSv for CZT SPECT MPI studies.
Stress testing with ETT, high-efficiency SPECT MPI, and stress-only protocols had a significantly lower patient radiation dose, fewer cardiac return visits, and less follow-up diagnostic testing than CTA. CTA had a shorter time to disposition, but there was a trend towards more discharges from the ED with stress testing.
Poster Sessions, Expo North
Saturday, March 09, 2013, 10:00 a.m.-10:45 a.m.
Session Title: Imaging: CT/Multimodality II
Abstract Category: 20. Imaging: CT/Multimodality
Presentation Number: 1141-338
- 2013 American College of Cardiology Foundation