A retrospective cost analysis of angioplasty compared to bypass surgery for lower limb arterial disease in an Australian tertiary health service

Therapeutic Potential for Beta-3 Adrenoreceptor Agonists in Peripheral Arterial Disease and Diabetic Foot Ulcers

Annually, peripheral arterial disease is estimated to cost over USD 21 billion and diabetic foot disease an estimated at USD 9-13 billion. Mirabegron is a TGA-approved beta-3 adrenoreceptor agonist, shown to be safe and effective in the treatment of overactive bladder syndrome by stimulating bladder smooth muscle relaxation. In this review, we discuss the potential use of beta-3 adrenoreceptor agonists as therapeutic agents repurposed for peripheral arterial disease and diabetic foot ulcers. The development of both conditions is underpinned by the upregulation of oxidative stress pathways and consequential inflammation and hypoxia. In oxidative stress, there is an imbalance of reactive oxygen species and nitric oxide. Endothelial nitric oxide synthase becomes uncoupled in disease states, producing superoxide and worsening oxidative stress. Agonist stimulation of the beta-3 adrenoreceptor recouples and activates endothelial nitric oxide synthase, increasing the production of nitric oxide. This reduces circulating reactive oxygen species, thus decreasing redox modification and dysregulation of cellular proteins, causing downstream smooth muscle relaxation, improved endothelial function and increased angiogenesis. These mechanisms lead to endothelial repair in peripheral arterial disease and an enhanced perfusion in hypoxic tissue, which will likely improve the healing of chronic ulcers.

The Effect of Patient and Hospital Characteristics on Total Costs of Peripheral Bypass in New York State

INTRODUCTION

With the aging U.S. population, peripheral vascular procedures will become increasingly common. The objective of this study is to characterize the factors associated with increased total costs after peripheral bypass surgery.

METHODS

Data for 34,819 patients undergoing peripheral bypass surgery in NY State were extracted using the Statewide Planning and Research Cooperative System (SPARCS) database for years 2009-2017. Patient demographics, All Patient Refined Diagnostic Related Groups (APR) severity score, mortality risk, hospital volume, and length of stay data were collected. Primary outcomes were total costs and length of stay. Data were analyzed using univariate and multivariate analysis.

RESULTS

28.1% of peripheral bypass surgeries were performed in New York City. 7.9% of patients had extreme APR severity of illness whereas 32.0% had major APR severity of illness. 6.3% of patients had extreme risk of mortality and 1 in every 5 patients (20%) had major risk of mortality. 24.9% of patients were discharged to a facility. The mean length of stay (LOS) was 9.9 days. Patient LOS of 6-11 days was associated with +$2,791.76 total costs. Mean LOS of ≥ 12 days was associated with + $27,194.88 total costs. Multivariate analysis revealed risk factors associated with an admission listed in the fourth quartile of total costs (≥$36,694.44) for peripheral bypass surgery included NYC location (2.82, CI 2.62-3.04), emergency surgery (1.12, CI 1.03-1.22), extreme APR 2.08, 1.78-2.43, extreme risk of mortality (2.73, 2.34-3.19), emergency room visit (1.68, 1.57-1.81), discharge to a facility (1.27, CI 1.15-1.41), and LOS in the third or fourth quartile (11.09, 9.87-12.46).

CONCLUSION

The cost of peripheral bypass surgery in New York State is influenced by a variety of factors including LOS, patient comorbidity and disease severity, an ER admission, and discharge to a facility.

Treatment of bypass failure in patients with chronic limb threatening ischemia – open surgery vs. percutaneous mechanical thrombectomy

Summary: Background: Lower limb bypass occlusion in patients with chronic limb threating ischemia remains a challenge. We can choose between different treatment options: open surgery, local thrombolysis, thrombectomy/atherectomy devices. In this pilot study, we compare clinical outcomes and treatment costs between open surgery (OS) and percutaneous mechanical thrombectomy (pMTH). Patients and methods: This pilot study represents a retrospective analysis of hospital data of 48 occluded bypasses admitted from 2013 to 2018. Only patients presenting with severe ischemia and recrudescence of symptoms (Rutherford 4–6) were included in the current analysis. Two cohorts of patients were analysed: patients who underwent OS and patients that underwent pMTH. Primary clinical outcomes were one-year cumulative patency and limb salvage rates. Total cost was calculated as a sum of intra- and post-operative costs. To weigh clinical benefits against the economic consequences of OS versus pMTH a cost-effectiveness framework was adopted. Results: We analysed a series of 48 occluded bypasses 17 treated with open surgery and 31 with pMTH. Procedural success was 100% in both groups. When comparing one-year death rates ( p-value = .22) and re-occlusion rates ( p-value = .43), no statistically significant differences were observed between the two cohorts. Mean patency duration in the surgery cohort was significantly shorter ( p-value < .05). Primary patency (OS 41.2% vs. pMTH 48.4%) and limb salvage rate (OS 88.2% vs. pMTH 90.3%) at one year are similar in both groups. The total cost of surgery was substantially higher (OS 10,159€ vs. pMTH 8,401€) Conclusions: This pilot study, although limited to 48 occluded bypasses, demonstrates that endovascular treatment with pMTH is less invasive, less time consuming and less expensive, and produces greater health benefits than traditional OS.

Comparison of Outcomes and Cost of Endovascular Management Versus Surgical Bypass for the Management of Lower Extremities Peripheral Arterial Disease

The management of lower extremities peripheral arterial disease (LE-PAD) has always been debatable. We sought to explore in-hospital outcomes in hospitalizations that underwent endovascular or bypass surgery for LE-PAD from nation's largest, publicly available database. The National Inpatient Sample from 2012 to 2014 was queried to identify adult hospitalizations underwent endovascular management and bypass surgery for LE-PAD. Appropriate International Classification of Diseases, Ninth Revision, Clinical Modification diagnostic and procedural codes were utilized to identify hospitalizations. A total of 89,256 hospitalizations were identified having endovascular management or bypass surgery for LE-PAD. More hospitalizations underwent endovascular intervention as compared with bypass surgery. Overall, hospitalizations for endovascular management had higher baseline co-morbidities and older age. A propensity score matched analysis was performed to compare in-hospital outcomes. After matching, 28,791 hospitalizations were included in each group. In-hospital mortality was significantly lower with endovascular intervention procedure as compared with surgical bypass group (1.5% vs 2.5%, p ≤0.001). All other secondary outcomes were noted lower with endovascular management except stroke and postprocedural infection. Taken together, these may account for higher discharges to home, lower length of stay, and less cost of hospitalizations associated with endovascular management. In conclusion, endovascular management is associated with lower in-hospital morbidity, mortality, length of stay, and cost when compared with bypass surgery in this study.