Prognostication in the era of a new stressor for myocardial perfusion imaging

Review of Cardiovascular Imaging in the Journal of Nuclear Cardiology in 2015-Part 2 of 2: Myocardial perfusion imaging

In 2015, the Journal of Nuclear Cardiology (®) published many high-quality articles. In this series, we will summarize key articles that have appeared in the Journal last year to provide for the interested reader a quick review of the advancements that have recently occurred in the field. In the first article of this 2-part series, we concentrated on publications dealing with plaque imaging, cardiac positron emission tomography, computed tomography, and magnetic resonance. This review will focus on myocardial perfusion imaging summarizing advances in the field including in diagnosis, prognosis, and appropriate use.

Comparison of the prognostic value of regadenoson and adenosine myocardial perfusion imaging

BACKGROUND

Regadenoson is now widely used in single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). However, the prognostic value of abnormal stress perfusion findings with regadenoson vs adenosine are unclear. The aim of this study was to evaluate the prognostic value of regadenoson SPECT and to compare it to that of adenosine SPECT.

METHODS AND RESULTS

3698 consecutive patients undergoing either adenosine or regadenoson SPECT were assessed at 1 year for the endpoints of cardiovascular death and a composite endpoint of cardiovascular death or MI. Weighted Cox proportional hazards regression modeling with the inverse probability weighted (IPW) estimators method adjusting to propensity for agent was used to account for differences in baseline characteristics. Patients undergoing adenosine SPECT MPI had a significantly higher prevalence of smoking history, diabetes, hypertension, and prior myocardial infarction (P < .05, all). At 1 year of follow-up, there were 154 cardiovascular deaths and 204 with the composite endpoint of cardiovascular death or MI. Using IPW adjustment to propensity for agent in a model with stress agent, summed stress score (SSS) remained a significant predictor of the composite endpoint of cardiovascular death or MI (HR 1.36 CI 1.28-1.46; P < .0001) as well as cardiovascular death (HR 1.38 CI 1.28-1.49; P < .0001). The interaction of SSS with agent was not significant. Similar findings were seen with summed difference score (SDS).

CONCLUSIONS

SSS derived from either adenosine or regadenoson SPECT MPI is a significant predictor of events and provides incremental prognostic information beyond basic clinical variables. We have shown for the first time that use of regadenoson vs adenosine as stress agent does not modify the prognostic significance of SSS. Similar findings were seen with SDS.