Abstract Body: Introduction
Individuals with a non-dominant right coronary artery (RCA) have a high incidence of false positive reversible perfusion defects in the inferior wall on SPECT MPI. This phenomenon is attributed to the reduced perfusion territory supplied by a non-dominant RCA, leading to relative hypoperfusion. However, it is not well known whether the use of PET MPI is associated with a similar incidence of false positive reversible perfusion defects in the inferior wall for individuals with a non-dominant coronary anatomy. It is assumed that PET MPI has a higher sensitivity for detecting coronary artery disease (CAD) when compared to SPECT MPI. The purpose of our study was to determine the prevalence of individuals with non-dominant coronary anatomy who experienced false positive reversible perfusion defects with PET MPI stress tests.

Hypothesis
We addressed the hypothesis that the use of PET MPI, a statistically superior imaging modality for identifying obstructive CAD as compared to SPECT MPI, would eliminate the occurrence of false positive reversible perfusion defects in the RCA territory with non-dominant coronary anatomy.

Methods
Our study screened 259 patients who underwent PET MPI from 2018 to 2023 and had reversible perfusion defects in the RCA territory. Those with obstructive CAD on angiography were excluded, so statistical analysis was performed on 94 patients without obstructive or with non-obstructive CAD (false positive). The prevalence of non-dominant RCA in the cohort was established using frequency and percentage statistics. Chi-square and t-tests were used to compare the RCA groups on demographic and clinical parameters.

Results
Within the false positive cohort, 21 patients had non-dominant RCA (22.3%). There was no difference between the dominant and non-dominant RCA groups for age (p=0.41), sex (p=0.41), ethnicity (p=0.90), BMI (p=0.73), or history of CABG (p=0.68).

Conclusion
In conclusion, even with PET MPI, there is a high incidence of false positive reversible perfusion defects in the RCA territory in patients with non-dominant coronary anatomy.