Risk stratification with pre-operative myocardial perfusion imaging

Area of Science:

• Cardiology
• Cardiovascular Imaging
• Peri-operative Medicine

Background:

• Myocardial perfusion imaging (MPI) is utilized for cardiac risk stratification in patients undergoing non-cardiac surgery.
• Existing data supporting MPI's role is limited to single-center studies and predates contemporary coronary artery disease (CAD) therapies.
• The clinical utility of pre-operative MPI in the current therapeutic landscape requires re-evaluation.

Purpose of the Study:

• To assess the association between pre-operative testing indications and cardiovascular outcomes (death or myocardial infarction [MI]).
• To identify predictors of death or MI in patients undergoing non-cardiac surgery who received pre-operative MPI.
• To evaluate the impact of pre-operative MPI referral on patient outcomes.

Main Methods:

• Analysis of the international, multicenter REFINE-SPECT registry, including 32,711 patients.
• Classification of patients into pre-operative testing indication and non-pre-operative testing groups.
• Evaluation of the association between pre-operative testing and the incidence of death or MI, with further analysis in the pre-operative testing cohort.

Main Results:

• Patients referred for pre-operative testing had a significantly higher incidence of death or MI (4.4% vs. 1.6%, p < 0.001).
• In the pre-operative testing group, stress, rest, and ischemic total perfusion deficits were associated with death or MI.
• Resting total perfusion deficit independently predicted death or MI (aHR 1.25, 95% CI 1.07-1.45), while pharmacologic stress testing did not (aHR 0.88, 95% CI 0.70-1.12).

Conclusions:

• Pre-operative SPECT MPI identifies patients at increased cardiovascular risk, potentially due to selection bias or unmeasured confounders.
• Resting perfusion abnormalities on MPI are valuable in identifying high-risk patients.
• These findings can inform peri-operative care strategies for surgical patients.