Aortoiliac calcification correlates with 5-year survival after abdominal aortic aneurysm repair.

BACKGROUND: An anatomic severity grade (ASG) score to categorize and to define anatomic factors for abdominal aortic aneurysm (AAA) repair was proposed. Other studies have previously reported that aortic anatomic complexity is a marker of survival and resource utilization after repair, although it remains unclear whether individual components of the ASG score independently contribute to survival. This study analyzed and validated an aortic and iliac artery calcium scoring system that can potentially predict survival after AAA repair. METHODS: Patients who underwent infrarenal AAA repairs from July 2007 to May 2012 were analyzed using complete 5-year records. Those who died ≤30 days of surgery were excluded. Calcium score (CS) was defined using the ASG scoring system for its basis by preoperative imaging <6 months before surgery. A CS for any patient was 0 to 5 points, the sum of the points assigned to aortic neck (2 points total) and iliac artery (3 points total) calcification. A receiver operating characteristic curve was used to determine a CS threshold for mortality. The 5-year survivors and deaths were compared in regard to comorbidities, pharmacology, and CS at or above the defined threshold. Each variable with a P value <.1 between the groups was then placed into a Cox proportional hazards model, with statistical significance of P < .05. RESULTS: There were 356 patients who underwent AAA repair with complete 5-year follow-up data; 26% died within 5 years of surgery. Of these, 13% had CS of 0 with 15% mortality, 28% had CS of 1 with 21% mortality, 24% had CS of 2 with 24% mortality, 23% had CS of 3 with 35% mortality, 10% had CS of 4 with 40% mortality, and 2% had CS of 5 with 17% mortality. The receiver operating characteristic curve demonstrated an appropriate threshold of CS 3. Of these patients, 65% had a CS <3, whereas 35% had a CS ≥3. Patients with a CS ≥3 had a lower 5-year survival probability (P = .003). Comparing 5-year survivors and deaths in a Cox proportional hazards analysis, CS ≥3 was associated with a hazard ratio of 1.579 (95% confidence interval, 1.038-2.402; P = .0328). CONCLUSIONS: A CS ≥3 is linked to a lower 5-year survival after AAA repair in our population. This system potentially can be another measure for risk stratification and serve as a means to predict midterm mortality in AAA repairs. Future study will be needed for further validation to predict midterm mortality and to better guide surgical decision-making.

TREO Aortic Endograft Demonstrates Significant Aneurysmal Sac Shrinkage.

BACKGROUND: Aneurysmal sac shrinkage is associated with successful aneurysm repair after endovascular aortic repair (EVAR). There are a variety of approved aortic endografts, with a recent study demonstrating increased sac shrinkage in certain endografts compared with others. The TREO endograft (Terumo Aortic Ltd, Renfrewshire, Scotland, UK) is being evaluated for use in EVAR, with preliminary data demonstrating high rates of success. The objective of this study is to evaluate sac shrinkage of the TREO endograft. METHODS: This is a retrospective analysis of EVARs at a single institution by a high-volume surgeon over a 1-year period in which the TREO graft was used. The change in sac size and rate of sac shrinkage (mm/mo) were evaluated between TREO and non-TREO grafts. All TREO grafts were included in the analysis. Non-TREO grafts were matched a priori for TREO indications for use anatomic specifications. Non-TREO grafts were also excluded for traumatic or emergent cases. The primary outcome was sac shrinkage, and secondary outcomes were composite complication profile within 30 d of operation. RESULTS: Six TREO grafts and 16 non-TREO grafts were included for analysis. The groups were similar in age, gender, and race. The groups were also similar in aortic anatomy before EVAR. The aneurysm sac shrinkage rate (mm/mo) is significantly greater in the TREO group than in the non-TREO group (0.484 ± 0.107 versus 0.018 ± 0.112, P = 0.033). The total average size of sac shrinkage was also greater for the TREO group (-0.688 ± 2.262 versus 12.00 ± 2.78, P < 0.001). The composite complication profile of stroke, myocardial infarction, death, and respiratory complications was not different between groups. CONCLUSIONS: TREO aortic endografts for aneurysm repair are being used in Europe. However, their application in the United States is limited. Our data demonstrate the significant advantage the TREO graft has with increased sac shrinkage and minimal complications, compared with other grafts. This study adds to the growing body of literature supporting TREO graft use for EVAR.

Bundling of Reimbursement for Inferior Vena Cava Filter Placement Resulted in Significantly Decreased Utilization between 2012 and 2014.

BACKGROUND: On January 1, 2012, reimbursement for inferior vena cava filters (IVCFs) became bundled by the Centers for Medicare and Medicaid Services. This resulted in ICVF placement (CPT code 37191) now yielding 4.71 relative value units (RVUs), a decrease from 15.6 RVUs for placement and associated procedures (CPT codes 37620, 36010, 75825-26, 75940-26). Our hypothesis was that IVCF utilization would decrease in response to this change as other procedures had done once they had become bundled. METHODS: Including data from 2010 to 2011 (before bundling) and 2012 to 2014 (after bundling), we utilized 5% inpatient, outpatient, and carrier files of Medicare limited data sets and analyzed IVCF utilization before and after bundling across specialty types, controlling for total diagnosis of deep vein thrombosis (DVT) and pulmonary embolism (PE) (ICD-9 codes 453.xx and 415.xx, respectively) and placement location. RESULTS: In 2010 and 2011, the rates/10,000 DVT/PE diagnoses were 918 and 1,052, respectively (average 985). In 2012, 2013, and 2014, rates were 987, 877, and 605, respectively (average 823). Comparing each year individually, there is a significant difference (P < 0.0001) with 2012, 2013, and 2014 having lower rates of ICVF utilization. Comparing averages in the 2010-2011 and 2012-2014 groups, there is also a significant decrease in utilization after bundling (P < 0.0001). CONCLUSIONS: Following the bundling of reimbursement for IVCF placement, procedural utilization decreased significantly. More data from subsequent years will be needed to show if this decrease utilization continues to persist.

Increased initial cement-bone interlock correlates with reduced total knee arthroplasty micro-motion following in vivo service.

Aseptic loosening of cemented tibial components in total knee arthroplasty (TKA) has been related to inadequate cement penetration into the trabecular bone bed during implantation. Recent postmortem retrieval work has also shown there is loss of interlock between cement and bone by resorption of trabeculae at the interface. The goal of this study was to determine if TKAs with more initial interlock between cement and bone would maintain more interlock with in vivo service (in the face of resorbing trabeculae) and have less micro-motion at the cement-bone interface. The initial (created at surgery) and current (after in vivo service) cement-bone interlock morphologies of sagittal implant sections from postmortem retrieved tibial tray constructs were measured. The implant sections were then functionally loaded in compression and the micro-motion across the cement-bone interface was quantified. Implant sections with less initial interdigitation between cement and bone and more time in service had less current cement-bone interdigitation (r(2)=0.86, p=0.0002). Implant sections with greater initial interdigitation also had less micro-motion after in vivo service (r(2)=0.36, p=0.0062). This work provides direct evidence that greater initial interlock between cement and bone in tibial components of TKA results in more stable constructs with less micro-motion with in vivo service.