3D fusion between SPECT myocardial perfusion imaging and invasive coronary angiography to guide the treatment for patients with stable CAD

Objective We evaluated the value of three-dimensional (3D) fusion of SPECT myocardial perfusion imaging (MPI) with invasive coronary angiography (ICA) to guide coronary revascularization for patients with stable coronary artery disease (CAD). Methods A retrospective observational study of 621 patients who underwent SPECT MPI and ICA was conducted. Based on the location of perfusion deficit on SPECT MPI and stenosis on ICA, patients were classified into matched, unmatched, or normal groups via the fusion or side-by-side analysis. The treatments recommended by the fusion or side-by-side analysis were compared with those that the patients actually received. The treatment was defined as concordant if there was revascularization in concordance with the recommendation by the fusion or side-by-side analysis or if patient did not require revascularization; otherwise, it is classified as discordant. Major adverse cardiac events (MACE) were defined as all-cause and cardiac death, myocardial infarction, unstable angina requiring hospitalization or ICA, or unplanned revascularization. Results Over a five-year follow-up, 15.9% of patients experienced MACE. The MACE rates in the fusion and side-by-side groups were 19.8% and 24.4% for matched findings, 14.4% and 14.0% for unmatched findings, and 7.2% and 8.2% for normal findings, respectively (P<0.01). Among the 366 patients with at least one vessel stenosis of >50%, those who received the treatment concordant with fusion had significantly better outcomes compared to those who did not (16.8% vs 27.0%, P<0.05), particularly in the sub-group with intermediate stenosis (stenosis: 50-80%) (10.8% vs 26.5%, P<0.01). The treatment concordant with fusion is an independent protective factor against MACE (HR:0.48, CI:0.28-0.83 P<0.01) while the treatment concordant with the side-by-side analysis is not. The concordant group showed a significantly higher lesion vessel rate in the left circumflex artery (LCX) (31.2% vs. 14.3%, P<0.01) compared to the discordant group as classified by fusion. Conclusions 3D fusion before coronary revascularization can guide the treatment to improve outcomes among patients with known or suspected CAD, particularly those with intermediate stenosis. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial NCT04554134 ### Funding Statement This research was supported by a seed grant from Michigan Technological University Health Research Institute (PI: Weihua Zhou), and a grant from the National Nature Science Foundation of China (PI: Cheng Wang, 82100338). ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This study complied with the Helsinki declaration and local regulations and was approved by the ethics committee of the First Affiliated Hospital of Nanjing Medical University. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Data available on request from the authors