Prognostic utility of ischemic response in functional imaging tests (SPECT or stress echocardiography) in low-risk unstable angina patients

Cardiol J. 2015;22(2):160-4. doi: 10.5603/CJ.a2014.0052. Epub 2015 Feb 23.

Abstract

Background: The aim of this study is to determine the ability of ischemic response in imaging stress tests (single-photon emission computed tomography [SPECT] or stress echocardiography [SE]) to predict events in low-risk unstable angina patients.

Methods: Three hundred and fifty-nine patients with unstable angina (< 24 h), asymptomatic at admission, without ST-segment elevation or depression, normal troponins, and undergoing SPECT (n = 188) or SE (n = 171) during hospitalization (median = 1 day) were included. A positive imaging test (IMAGING+) was defined as the presence of reversible perfusion defects or wall motion abnormalities in at least 2 contiguous segments. Multivariate models were constructed using these results and clinical variables to predict events at 6 months.

Results: Ninety-nine (27%) patients had IMAGING+, 72/188 (38%) in SPECT and 27/17 (16%) in SE (p < 0.0001). Events occurred in 84 (23%) patients: 4 had myocardial infarction, 47 new hospitalizations due to angina and 33 coronary artery revascularizations. Independent predictors of coronary artery disease were: IMAGING+ (OR: 6.4, 95% CI: 3.4-11.8, p < 0.0001), history of coronary artery disease (OR: 2.5, 95% CI: 1.2-5.2, p < 0.02) and TIMI risk (OR: 1.5, 95% CI: 1.1-2.2, p < 0.03).

Conclusions: In low-risk unstable angina patients, an ischemic response in functional stress tests (SPECT or SE) was associated with adverse events and severe coronary artery disease.

MeSH terms

  • Aged
  • Angina, Unstable / diagnosis*
  • Angina, Unstable / diagnostic imaging
  • Angina, Unstable / therapy
  • Chi-Square Distribution
  • Coronary Artery Disease / diagnosis*
  • Coronary Artery Disease / diagnostic imaging
  • Coronary Artery Disease / therapy
  • Echocardiography, Stress*
  • Female
  • Humans
  • Length of Stay
  • Logistic Models
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Myocardial Revascularization
  • Odds Ratio
  • Predictive Value of Tests
  • Prognosis
  • Risk Assessment
  • Risk Factors
  • Severity of Illness Index
  • Time Factors
  • Tomography, Emission-Computed, Single-Photon*