Office-based lab mesenteric angiography is safe for low- and moderate-risk patients

<h2>Abstract:</h2><h3>Objective</h3> There has been a significant shift of vascular care and intervention from the inpatient to outpatient setting. The office-based laboratory (OBL) is an increasingly adopted treatment model following the 2008 payor reimbursement modifications for outpatient vascular intervention by the Centers for Medicare and Medicaid Services (CMS). Reports on this phenomenon largely focus on the financial effects with a paucity of safety and outcomes data associated with this treatment setting. In this study, we examine treatment outcomes of elective mesenteric angiograms performed at an OBL, and factors affecting patient selection for safe outpatient intervention. <h3>Methods</h3> A retrospective study was performed of adult patients treated with diagnostic or interventional mesenteric angiography at a single OBL over 9 years. Patient and treatment variables were abstracted from outpatient and inpatient medical records. Primary outcomes of interest were 30-day adverse events (30D A/E) reported with the Clavien-Dindo (CD) classification system. Technical success was examined as a secondary outcome. <h3>Results</h3> Between September 2015 and February 2024, 80 patients underwent 115 mesenteric angiograms by 7 vascular surgeons. Patients were 73 years old on average (SD=9.3, range 44 to 89), predominantly female (53 of 80 patients), predominantly low risk (97 of 115 angiograms were performed on patients with SVS/AAVS MCS<2), with a mean BMI of 25.9 (range 14.1 to 50.6, SD=6). The overall incidence of 30D A/Es was 6.1% (7 of 115), with a 5.2% 30D rate of morbidity (6 of 115), and 0.9% 30D rate of mortality (1 of 115). 6 of 7 cases with 30D A/Es were CD grade 3 or greater. An univariable comparison of mesenteric angiograms resulting in a 30D A/E to those without demonstrated no significant differences in mean age, race distribution, mean BMI, preoperative SVS/AAVS MCS, smoking history, history of malignancy, use of antithrombotic medications, history of prior mesenteric stents, or whether the procedure was performed for reintervention. On multivariable regression, technical failure was a significant predictor for complications CD 3 or greater (Odds Ratio [OR], 6.36; 95% CI, 1.1-37.4, p=.04) when correcting for inter-operator variability. <h3>Conclusion</h3> Variable complexity mesenteric angiography for primary and repeat intervention is safely performed at an office-based lab on selected low and moderate risk patients. Further study of anatomic and patient selection factors predicting technical failure is required.