Endoprosthesis

Data were retrieved from the vascular unit database, SecuTrial^® (interActive Systems GmbH, Berlin, Germany) and the CHUV electronic patient database. All data were anonymized.
Data from CTAs were analyzed with Vue-PACS^® (Carestream Health, Ontario, ON, Canada). Preoperative CTAs were compared to postoperative CTAs, both with 1 mm slices and centerline measurements using outer-to-outer diameters. If more than one postoperative CTA was done, the second of the two scans was considered the index CTA compared to the preoperative CTA.
Briefly, the following imaging data, taken from CTAs, were examined: neck diameter with four measurements starting from the level of the lowest renal artery with the calculation of the maximum diameter; neck length calculated as the distance between the lowest renal artery and the beginning of the aneurysm sac; degree of suprarenal neck angulation, calculated according to van Keulen, et al. [14 (link)] as the angle between the longitudinal axis of the suprarenal aorta and the longitudinal axis of the abdominal aortic aneurysm. In addition, thrombi and calcification at the aneurysm neck were measured according to wall extent. Thrombi or calcification present in one quadrant of the neck circumference was coded 25%, 50% in two quadrants, 75% in three quadrants and 100% in four quadrants.
The maximum aneurysm sac diameter was measured using the centerline. Aneurysm sac calcification was measured, as neck calcification, as a percentage of the circumference covered. We measured the maximum aortic diameter (MAD) of the sac, and the size of the flow lumen maximum diameter (FLMD), to calculate the thrombus index (TI) of the sac, using the formula TI = [(MAD − FLMD)/MAD]. Patency of the inferior mesenteric artery (IMA), and the number of patent lumbar arteries within the sac, were also evaluated by CTA, together with the maximum diameter of each common iliac artery (CIA). According to Rouby, et al. [15 (link)], any CIA of a maximum diameter ≥17 mm was classified as an aneurysm.
Finally, endoleaks were classified as Type I, Type II, or Type III. Compliance with the instructions for use (IFU) for Endurant^® endoprosthesis (https://www.medtronic.com/us-en/healthcare-professionals/products/cardiovascular/aortic-stent-grafts/endurantii/indications-safety-warnings.html, accessed on 27 May 2022) was analyzed, including neck length ≥10 mm, neck angulation ≤60 degrees, neck diameter 19–32 mm, and iliac diameter 8–25 mm. IFU were coded as a single binary variable. Any EVAR procedure with a single unmet IFU instruction was classified as non-compliant. Patient demographics; clinical features; and preoperative cardiological [16 (link)], respiratory [17 (link)] and renal [18 (link)] assessments were evaluated with ASA scoring, and entered into the database.

WRAPSODY Endoprosthesis (Merit Medical Systems, Inc.; South Jordan, Utah, USA) is a self-expanding, cell-impermeable endoprosthesis. The endoprosthesis is composed of a helically wound nitinol wire stent fully encapsulated in a multilayer fluoropolymer covering (Fig. 2). The covering’s luminal layer is composed of a spun polytetrafluoroethylene (spun PTFE) designed to limit fibrin deposition and thrombus formation. The cell-impermeable middle layer is designed to prevent transmural cell growth. The outer layer is made of a traditional expanded polytetrafluoroethylene (ePTFE), permitting cell-ingrowth for device anchoring. The device is offered in various sizes, ranging in diameter from 6.0–16.0 mm (allowing treatment of vessels from 4.6–14.4 mm in diameter) and ranging in length from 30−125 mm.Fig. 2

Study device. (A) Representative image of a 14 mm diameter x 30 mm device. (B) Cross-sectional schematic surrounding a single nitinol wire illustrating the organization of the multilayer graft covering. Similar to other stent grafts, the abluminal layer is composed of ePTFE to facilitate cell-ingrowth to anchor the device in place. Directly adjacent to the nitinol wire are layers of cell-impermeable fluoropolymer to prevent transmural cell migration through the graft covering. Below the innermost cell-impermeable layer is a second layer of porous ePTFE. The luminal surface of the graft is composed of a spun PTFE designed to reduce fibrin deposition and subsequent thrombus formation

In the period June–October 2022, data were collected from the National Endoprosthesis Registry on the total number of beneficiaries of elective primary and revision surgeries from the 120 orthopedic-traumatology hospitals/departments in Romania, after which their statistical processing was performed. The data were collected, preprocessed and filtered in Microsoft Excel, then transferred to GNU PSPP and Matlab for further processing.
For the elective hip and knee procedures: cemented hip, uncemented hip, partial hip, hybrid and reverse hybrid, cemented knee, hip revision, and knee revision, we examined the monthly trend in the number of surgeries in 2019 (Table 2), 2020 (Table 3), 2021 (Table 4), and 2022 until 1 September (Table 5).
We also collected the number of patients who presented monthly on an outpatient basis and who had surgery recommendations, for each of the 7 types of elective interventions, from which by combining we obtained the total number of recommended interventions in outpatient wards at ECCH. Then, for the patients who underwent one of the 7 surgical interventions studied, we collected the duration of hospitalization of the operated patient and the number of cases discharged at home.
At the end, from the financial reports of the hospitals, we extracted the average costs of the 7 types of elective interventions that we used in the economic calculation regarding the revenues recorded by the hospitals.
The methodology for processing the collected data consisted of a separate analysis for each of the seven studied issues.
In the analysis of the volumes of elective procedures of hip and knee, as there was a strong effect of the month of the year, we also calculated the three-month moving average (MA) of the number of cases of each of the 7 types of elective procedures of hip and knee to more easily examine any potential time trend during the quarter. In the analysis of the length of the operated patient’s hospital stay we calculated the average values of the hospitalization durations.
Statistical analysis was performed with Statistics and Machine Learning Toolbox Version 12.3 from Matlab R2022a (The Math Works, Inc., Natick, MA, USA).

The methodology of this study consisted of a retrospective analysis of the patients’ beneficiaries of primary and revision elective hip and knee surgery from 120 orthopedic-traumatology hospitals/departments in Romania. All patients, regardless of gender, who benefited from elective hip and knee interventions, namely: cemented hip, uncemented hip, partial hip, hybrid and reverse hybrid, cemented knee, hip revision, and knee revision, were recruited and included in the study.
For this we used 100% the data on payment requests for health care services for arthroplasty operations between 1 January 2019 and 1 September 2022 with the support of the data recorded in the National Endoprosthesis Registry [14 ]. A number of 53,748 subjects were included in the studies, who were diagnosed in the outpatient ward with the recommendation of elective surgery and who followed this intervention. Table 1 shows the gender of the patients participating in the study, of which 20,149 (37.49%) were men and 33,599 (62.51%) were women.
The study was approved by the Emergency County Clinical Hospital, from Targu Mures (ECCH).