An ambulatory, vascular surgery office-based approach to bariatric artery embolization

Abstract

Bariatric artery embolization (BAE) is a minimally invasive therapy for obesity that has primarily been described with postprocedural inpatient monitoring. Whether this procedure can safely be performed without mandatory inpatient monitoring remains unknown. We, therefore, herein report on a retrospective case series evaluating the safety and feasibility of BAE in an ambulatory, vascular surgery office-based setting. As such, six consecutive patients with class II obesity or greater underwent BAE at a single QUAD A-accredited office-based laboratory between December 2024 and August 2025. Five patients were female with a median age of 71 (range, 50-82) and a median body mass index of 42.6 (range, 35.2-49.3). Technical success, defined as cessation of flow within the targeted gastric fundal arteries on completion angiography, was achieved in all. Procedural success, defined as same-day discharge without unplanned hospitalization, was achieved in all. No adverse events of Society of Interventional Radiology grade 1 or higher were observed during the median follow-up duration of 9 months (range, 4-15 months). These findings suggest that BAE can be performed safely and feasibly in an ambulatory, office-based setting in appropriately selected patients, supporting further prospective evaluation of the outpatient BAE model.

Obesity represents a major health care challenge associated with cardiovascular morbidity and metabolic dysfunction, including diabetes mellitus and nonalcoholic fatty liver disease.¹ Current treatment paradigms focus on lifestyle changes, pharmacologic management, or bariatric surgery. Lifestyle changes may achieve modest weight reduction, but long-term durability is limited, and weight regain is common.² Pharmacotherapy provides improved efficacy but with limited broad access, high cost, known and serious side effects, and rebound weight gain on cessation.³ Bariatric surgery is the most durable and effective treatment for severe obesity. However, it is invasive, resource intensive, and may not be appropriate or acceptable for all.⁴ These limitations highlight the necessity for safe and effective, minimally invasive weight-loss interventions that bridge the gap between medical and surgical therapy with broader availability at a reasonable cost.

Bariatric artery embolization (BAE) has emerged as a novel endovascular intervention that promotes weight loss through selective embolization of the arteries supplying the stomach fundus—primarily, though not always exclusively, through the left gastric artery (LGA).⁵ The first-in-human experience with BAE was established by Kipshidze et al⁶ who reported the performance of gastric artery embolization for weight loss. Weiss et al⁷ at Johns Hopkins established the technical framework of the procedure. These experiences culminated in the Bariatric Embolization of Arteries for the Treatment of Obesity (BEAT) trial, a prospective single-arm study demonstrating clinically meaningful weight reduction with an acceptable safety profile at 1 year, establishing BAE as a viable endovascular intervention for obesity management.⁸ Early prospective studies and recent meta-analyses have demonstrated clinically meaningful weight reduction with acceptable safety profiles.^5,9 However, existing reports have primarily described BAE performed in inpatient or short-stay hospital settings. As health care systems continue to shift toward value-based care and ambulatory models, the question of whether BAE requires routine inpatient monitoring remains largely unanswered.

In this study, we present our experience with an ambulatory, vascular surgery office-based approach to BAE, focusing on procedural safety and feasibility, short-term outcomes, and preliminary weight loss signaling.

Methods

Study design

Six consecutive patients with class 2 or greater obesity underwent BAE by a single vascular surgeon (N.N.) at a single QUAD A-accredited office-based laboratory (OBL) between December 2024 and August 2025. Baseline patient characteristics collected included age, sex, baseline weight, body mass index (BMI), and obesity-related comorbidities, including hypertension, diabetes, hyperlipidemia, obstructive sleep apnea, and nonalcoholic fatty liver disease. Patient obesity was classified based on the World Health Organization’s definition predicated on BMI. Referred patients for BAE underwent multidisciplinary evaluation that determined bariatric surgery to be contraindicated, declined by patients, or inappropriate based on operative risk profile. Treatment with a glucagon-like peptide-1 receptor agonist was considered for all patients, but BAE was selected in the context of documented intolerance, contraindication, access limitations, or patient preference for a procedure rather than chronic pharmacologic intervention. These criteria align with published recommendations on patient selection.¹⁰

Inclusion criteria consisted of adults with class 2 obesity or greater who completed a prescribed and comprehensive nutritional counseling at an affiliated, dedicated hospital-based bariatric center, and those who were able to tolerate conscious sedation. In addition, all patients had documented failure of sustained weight loss despite completion of a structured, multidisciplinary weight management program prior to consideration for BAE. Exclusion criteria included prior gastric or upper gastrointestinal surgery altering vascular anatomy, prior bariatric procedures, current or pre-existing hepatobiliary pathology, history of pancreatitis, and noncompliance with mandatory preprocedural nutritional counseling. Follow-up duration was defined from the procedure to the most recent clinical evaluation. An institutional review board exemption was obtained for the retrospective review of the cases. All patients agreed to participate in the study.

Procedure

All procedures were performed under conscious sedation via a transradial approach under systemic heparinization to minimize inadvertent thromboembolic complications. Flush abdominal aortography in various obliquities was performed to identify and study aortic zones 6 to 8 visceral branch anatomy as demonstrated in Fig, A. Once the decision was made to proceed following initial aortography, a long, 5-French introducer sheath was placed into zone 6, and selective engagement of the celiac trunk was performed utilizing an angled catheter of choice—typically a Berenstein catheter (Cook Medical). Thorough selective celiac trunk angiography was performed in various orientations, examining the upper gastrointestinal and gastric arterial anatomy, paying careful attention to the fundal perfusion, and identifying the right and left gastric arteries, the common and proper hepatic arteries, the gastroduodenal artery, the splenic artery, the gastroepiploic arteries, and the pancreaticoduodenal arcades. Any vascular anomalies or anatomic variants (such as a replaced hepatic artery, various origins of the gastric arteries, the presence of the Arc of Buhler embryonic remnants, etc) were identified and taken into consideration prior to embolization so as to avoid the risk of inadvertent nontarget embolization. The senior operator has found that the best orientation for identifying the ostium of the LGA in the majority of cases to date is a caudal, left anterior oblique projection, as shown in Fig, C. That said, anatomy can be highly variable from patient to patient, and careful evaluation of arterial anatomy is mandatory. Once identified and road mapped, the LGA was then superselectively microcatheterized with a 2.4- or 2.5-French steerable microcatheter and a 0.014-inch guidewire (Asahi Intecc). Superselective angiography in anteroposterior projection confirmed proper placement within the terminal aspect of the LGA or other target vessels supplying the stomach fundus, which would be angiographically demonstrated on visceral phase runs. Once here, bland embolization was performed to stasis via 300- to 500-micron trisacryl gelatin microspheres (Embosphere Microspheres; Merit Medical Systems) to achieve adequate embolization while minimizing the risk of nontarget embolization. Completion angiograms showed preservation of the main trunk of the LGA with decreased fundal perfusion and no evidence of nontarget embolization as seen in Fig, E. A radial band was then applied following access removal, and heparin was partially reversed.

Fig.

A, Flush abdominal angiography reveals the celiac trunk and superior mesenteric artery. The splenic and common hepatic branches of the celiac trunk are visualized. B, Selective catheterization of the celiac trunk in caudal, left anterior oblique projection reveals the splenic, common, and proper hepatic, gastroduodenal, right gastroepiploic, and left gastric arteries (LGAs) coursing toward the stomach fundus and the right gastric artery. C, Steep caudal and left anterior oblique projections reveal the ostium and tortuous course of the LGA. D, Selective engagement of the LGA reveals extensive perfusion to the gastric fundus. E, Postembolization angiogram reveals the maintained main trunk of the artery with profoundly diminished gastric fundal flow.

Postprocedural regimen included the use of proton pump inhibitors for a minimum of 2 weeks postprocedurally, antinausea medications as needed, oral steroids for 48 hours to help mitigate local inflammation, promotility agents, and mucosal protectants. Narcotics were specifically avoided in favor of acetaminophen only for analgesia. Patients were maintained on a liquid-soft diet for 2 weeks postprocedurally with gradual progression to a Mediterranean-based diet as counseled preprocedurally.

Outcome measures

Technical success was defined as cessation of flow within the targeted LGA branches with angiographically confirmed reduction in fundal blush on completion angiography without evidence of significant residual fundal perfusion through collateral pathways. Procedural success was defined as uncomplicated same-day discharge without unplanned 30-day hospital admission. Procedural radiation metrics were recorded from the angiographic suite dose report for each case. Patients were monitored for weight loss, percent of total body weight loss (%TBWL), and change in BMI during follow-up. Weight measurements and BMI calculations were made during routine outpatient follow-up visits. Preliminary weight loss outcomes were assessed at the most recent follow-up visit, with follow-up duration reported individually given the nonstandardized intervals inherent to the retrospective nature of the study. Safety outcomes were categorized using the Society of Interventional Radiology classification system for adverse events.¹¹ Complications were identified through medical record review. Continuous variables were summarized as medians with ranges.

Results

Six patients were included in the review, five of whom were women, with a median age of 71 years (range, 50-82 years). The patients had a median preprocedural BMI of 42.6 kg/m² (range, 35.2-49.3 kg/m²) and a weight of 118 kg (range, 96-142 kg). Four patients were class III obese, whereas the remaining patients were class II. Preprocedural patient characteristics along with comorbidities are listed in Table I. Technical and procedural success was achieved in all six patients. There were no periprocedural or late Society of Interventional Radiology grade 1 or greater adverse events. Median fluoroscopy time was 25.9 minutes (range, 16.2-48.1 minutes). Median radiation dosimetry was 933.5 mGy (range, 514-1810 mGy). Preliminary weight loss outcomes are summarized in Table II. At a median follow-up of 9 months (range, 4-15 months), patients saw a median absolute weight loss of 12.7 kg (range, 8.4-23.5 kg), %TBWL of 9.9% (range, 7-24.5%), and a decrease in BMI of 4.2 kg/m² (range, 3-8.6 kg/m²).

Table I.

Baseline characteristics and comorbidities by patient prior to BAE in an ambulatory setting

Patient	Age	Sex	Preprocedure weight (kg)	Preprocedure BMI (kg/m2)	Hypertension	Type 2 diabetes	Hyperlipidemia	Obstructive sleep apnea
1	81	F	118	43.3	Yes	Yes	Yes	Yes
2	81	M	133.3	43.4	Yes	Yes	Yes	Yes
3	50	F	142	49.3	Yes	Yes	Yes	Yes
4	82	F	103.4	38	Yes	No	Yes	No
5	66	F	96	35.2	Yes	Yes	Yes	No
6	72	F	118	42	Yes	Yes	Yes	Yes

BAE, Bariatric artery embolization; BMI, body mass index; F, female; M, male.

Table II.

Weight loss data by patient after BAE

Patient	Postprocedure weight (kg)	Postprocedure BMI (kg/m2)	Follow-up length (mo)	%TBWL	Total weight loss (kg)
1	108.9	39.9	9	7.7	9.1
2	117.9	38.4	9	11.6	15.4
3	132	47.4	9	7	10
4	95	36	9	8.1	8.4
5	72.5	26.6	4	24.5	23.5
6	95	33.9	15	19.5	23

BAE, Bariatric artery embolization; BMI, body mass index; %TBWL, percent of total body weight loss.

Discussion

No prior published series has specifically evaluated the safety and feasibility of BAE performed in an ambulatory, vascular surgery OBL setting. The weight reduction observed in this cohort is consistent with prior prospective series of hospital-based BAE.^9,12, 13, 14, 15 From a safety standpoint, the absence of adverse events noted in our cohort aligns with published safety data, demonstrating predominantly self-limited gastritis without procedure-related mortality.12, 13, 14, 15, 16 These procedural radiation metrics are consistent with published BAE dosimetry data ranging from 1369 mGy in the ambulatory GET LEAN series to 5255 mGy in the hospital-based BEAT trial.⁵

The mechanism underlying BAE relies on selective reduction of blood flow to the gastric fundus, the primary anatomic source of ghrelin.^5,17 Ghrelin is a peptide hormone produced by fundal oxyntic gland endocrine cells that mediates orexigenic signaling to the central nervous system, which in turn regulates food intake and adipose deposition. Reduction in fundal perfusion attenuates ghrelin production, resulting in appetite modulation and early satiety. This mechanism is supported by ghrelin suppression demonstrated across prospective clinical series.^5,9

The procedural foundation of BAE was pioneered by Kipshidze et al⁶ as well as Weiss et al⁷ at Johns Hopkins, whose landmark pilot series demonstrated the safety and technical feasibility of LGA embolization for weight loss. The subsequent BEAT trial confirmed clinically meaningful weight reduction with an acceptable safety profile at a 1-year follow-up.⁸ These studies established the technical parameters and patient selection, subsequently replicated by independent groups across multiple centers.12, 13, 14, 15, 16 These findings were synthesized in a 2023 international review by Ravetta et al, which confirmed a mean weight loss of 8.68 kg at 1 year, with sustained reductions of 7.7% to 9.0% TBWL at 2 years. This study reinforced that BAE is intended as a minimally invasive counterpart for patients with class II or greater obesity who are ineligible for surgical intervention, a patient selection framework consistent with the present study.⁵ Despite this growing evidence base, no prior series has evaluated the feasibility of BAE in an ambulatory OBL setting. The present series directly addresses this gap, demonstrating that the safety and technical success established in hospital-based series can be replicated in the ambulatory environment.

BAE is an elective procedure performed on a well-defined and anatomically predictable vascular target. Published adverse events have been predominantly mild, and only a single major complication of acute pancreatitis requiring intensive care admission has been reported across the BAE literature.¹⁵ One study demonstrated the feasibility of BAE with same-day discharge from a freestanding interventional center, which showed similar results and had no major adverse outcomes.¹⁶ In our cohort, no patients demonstrated hemodynamic instability, delayed adverse events, or need for escalation of care. Collectively, these data suggest that routine inpatient monitoring may not be required in appropriately selected patients undergoing BAE in the ambulatory setting.

The economic implications of an ambulatory office-based model for BAE merit dedicated consideration. Site-of-service payment differentials have systematically incentivized the migration of procedural care toward higher-cost hospital-based settings, driven by revenue generation rather than care quality or efficiency.^18,19 In the context of obesity management, the cost differential between treatment modalities is substantial. Bariatric surgery carries a substantial cost ranging from $14,000 to $35,000, whereas chronic glucagon-like peptide-1 receptor agonist therapy accrues a cost of $4200 to $12,000 annually without definitive treatment end points.^20,21 The OBL setting offers a structurally lower-cost alternative with reduced facility overhead, lower anesthesia requirements, and the elimination of inpatient stay costs.²² A vascular quality initiative analysis of over 66,000 endovascular interventions demonstrated no significant differences in hospital admission rates, cardiac, pulmonary, or renal complications, or technical success across hospital outpatient, ambulatory surgery center, and OBL settings.²³ These findings provide objective infrastructure support for the ambulatory model. Formal health economic analysis remains a priority end point for future prospective trials of ambulatory BAE.

The study is limited by its small sample size, single-center design, and variable follow-up intervals, and the absence of a control arm precludes assessment of relative effectiveness compared with other more established therapies. Furthermore, our median follow-up time of 9 months precludes assessment of long-term durability beyond the early postprocedural period. These findings are appropriately interpreted as preliminary and hypothesis generating. Larger multicenter studies with standardized follow-up are necessary to establish durability of outcomes, define risk profiles, and create appropriate patient selection criteria for the ambulatory setting.

This series suggests that BAE performed in an ambulatory, vascular surgery office-based setting can provide similar early clinical outcomes without the resource burden of mandatory inpatient monitoring. Transitioning this procedure into the ambulatory setting could represent a financial benefit to the ever-increasing cost of the treatment of obesity. These findings support further prospective evaluation of ambulatory BAE and its potential role in the evolving multidisciplinary management of obesity.

Funding

None.

Disclosures

None.