Late Failure of a Polyethylene Unicompartmental Knee Insert -Retrieval Analysis Protocol and Results

This study reports the investigation of a degraded polyethylene insert retrieved after the catastrophic failure of a mobile bearing knee implant, occurred after a traumatic event and leading to a late revision. Understanding wear mechanisms of polyethylene components is important to improve the implants for joint replacement. This model of unicompartmental arthroplasty, due to its mobile, congruent insert and design, has the potential to attain low rates of wear, leading to an improved survival of the prosthesis over fixed-bearing knee implants. During the surgical technique, however, it is critical to avoid any source of impingement or incongruent articulation, as this are associated with increased rates of polyethylene wear and may contribute to the early necessity for revision surgery. The investigated insert presented a macroscopic fragmentation, surface and bulk defects and debris. Characterization of the retrieved polyethylene implant fragments was performed by macroscopic examination, by scanning electron microscopy and Fourier transform infrared spectroscopy. Due to a systematic retrieval analysis according to current standards, we can question that, in our case, third body wear is rarely pure bone or pure cement debris related but a combination of the two mentioned. The combination enhanced contribution of polyethylene debris in severe wear initiation and progression. Complete examination of the explants exhibiting breakage or severe wear may help in understanding pathogenic ways of failure in unicompartmental knee.

272 Combined rotational atherectomy and intravascular lithotripsy for heavy calcified coronary artery

Aims Percutaneous coronary intervention (PCI) of heavily calcified coronary lesions still represents a challenge for interventional cardiologists, with higher risk of immediate complications, late failure due to stent underexpansion or malapposition and consequent poor clinical outcome. Rotational atherectomy (RA) is a well-known calcium debulking modality. However, when coronary plaques present a significant amount of circumferential deep calcium, RA alone may not be able to achieve adequate lesion preparation. The combined use of intravascular lithotripsy (IVL) and RA, a technique called ‘Rotatripsy’, can be an effective approach in order to enable optimal stent implantation. We present a case of a calcific right coronary artery (RCA) PCI successfully treated by ‘Rotatripsy’ technique. Methods and results A 78-years-old man presented to our emergency department complaining of acute chest pain and dyspnoea. The electrocardiogram revealed ST-segment elevation in aVR and a diffuse ST-segment depression. Transthoracic echocardiography showed left ventricular anterior, septal, and apical walls akinesia. An urgent coronary angiography showed a critical distal left main (LM) stenosis involving the left anterior descending (LAD) artery ostium and a heavy calcified dominant RCA with two tandem sub-occlusive stenosis in the mid segment (Figure 1A). An immediate PCI with two drug eluting stents (DES) in the LM and LAD was performed. The patient was scheduled two days later for RCA PCI. RCA was engaged via left radial approach with a 6-Fr AL1 guiding catheter and the lesions were crossed with a Sion Blue wire. Using a Finecross MG microcatheter, an extra-support Rotawire was placed distally in the RCA. However, after multiple rotablation with 1.5 mm burr (Figure 1B), the mid segment lesion (Figure 1C) was still undilatable with a 3.5 mm non-compliant balloon (NCB) at 22 atm showing a partial dog bone effect (Figure 1D). We decided to attempt adjunctive IVL for calcium debulking. Using a Finecross MG and the trapping technique, a Gran Slam wire was placed distally; a 4.0 mm IVL balloon was delivered at the undilatable lesion and 80 pulses were applied (Figure 1E). Once the IVL treatment was completed (Figure 1F), a 4.0 mm NCB was inflated to 20 atm to further dilate the segment with an optimal expansion (Figure 1G). Finally, a DES Synergy 4.0 × 48 mm was implanted (Figure 1H) and it was post-dilated with a 4.5 mm NCB inflated to 22 atm (Figure 1I) with a perfect angiographic result (Figure 1J). Conclusions Coronary calcifications can lead to stent underexpansion, which is related to a higher rate of future complications, such as restenosis or thrombosis. If conventional lesion dilatations are not effective, alternative techniques should be considered (cutting balloon, scoring balloon, RA, orbital atherectomy, IVL). In case of circumferential deep calcium plaques, RA may not be able to achieve an adequate lesion preparation. RA allows the treatment of intimal calcium and permits to cross balloons or stents through severe lesions. However, when adequate expansion of the balloons is not achieved after RA, Shockwave IVL, that is not usually able to cross critical stenosis due to its bulky profile, represents an optimal complementary device, in order to fracture deep calcium and facilitate stent delivery and optimal expansion. In this case, we have successfully used the hybrid approach called ‘Rotatripsy’, which combines RA and IVL, in order to avoid more aggressive RA, which would have required the use of 7-Fr guiding catheter setting and may have increased the risk of complications.

The Dilemma after Sealing an Endovascular Aortic Aneurysm – Three Ways Out

Introduction Endovascular aneurysm sealing (EVAS) was commercially introduced in 2013. The initial results of EVAS were positive, leading to its widespread use. The mid- and long-term reports showed greater than expected rates of migration, which led to a recall of the device. In the present article, we describe our experience in managing type Ia endoleaks and migration occurring with the Nellix system in three different ways: open repair with Nellix explantation, Nellix-in-Nellix application (NINA technique), and the use of the multibranched Colt device originally dedicated to the treatment of thoracoabdominal aneurysms. Materials and Methods From February 2014 to June 2021, we performed 20 procedures for failed EVAS or ChEVAS (migration, type Ia endoleak, secondary aneurysm rupture). All patients treated for EVAS failure were male, aged 65 – 79. Results Seven Nellix explantations were performed. Three patients were admitted to our hospital with ruptured aneurysms that occurred 3 weeks to 4 years (mean 124 weeks) after EVAS, and another four with type Ia endoleak. In all but one case, removal of the Nellix system was easy. In two patients, tube grafts were implanted and in the remaining five cases, bifurcated grafts were implanted. In four patients, graft legs were anastomosed with the internal iliac arteries. One patient with secondary aneurysm rupture died from multiorgan failure on the 4th postoperative day. In two cases, transient renal failure was noticed in the perioperative period. All patients were admitted to the intensive care unit for 1 to 4 days (mean 2 days). The mean hospital stay was 9 days. All patients stayed in follow-up (3 – 56 months), but no other complications occurred. Eight patients were treated with the NINA technique: five for distal migration of the Nellix and three for failed ChEVAS. Four patients had a NINA procedure performed with three chimneys, three with two and one with one chimney. In one case, two iliac limbs were implanted to avoid kinking of the external iliac arteries. The median hospitalization time after the procedure was 9 days (range 3 – 12). Four patients developed transient acute renal insufficiency in the perioperative period. The follow-up ranged between 4 and 72 months. In one patient, deterioration of preexisting chronic renal insufficiency developed 5 months after the procedure, but dialysis was not required. One patient died from exacerbation of heart failure 7 months after the NINA procedure. The Colt device was implanted in five patients for the treatment of distal migration with type Ia endoleaks. None of the patients developed any signs of spinal cord ischemia. All patients were admitted to the intensive care unit for 1 or 2 days. In two cases, transient acute renal failure was noticed in the perioperative period. The mean hospital stay was 9 days. All patients remained in follow-up (6 – 22 months). In one case, the occlusion of the celiac trunk branch was found in contrast computed tomography 1 month after implantation of the Colt device, but without any symptoms. No other complications occurred. Conclusions Normal strategies for the management of complications for late failure of EVAR, including stent-graft extensions, are not suitable after EVAS; therefore, alternatives are necessary. Conversion to open repair carries an extensive burden on the patient, so it is not recommended for patients with high surgical risk. The use of a Nellix-in-Nellix application to treat late failure of EVAS is not within the instructions for use but could be an effective strategy for a type Ia endoleak with or without migration. The use of this technique has been extremely limited since the Nellix system was recalled from the market. The use of the Colt multibranched device may be an alternative option, but due to the small number of patients, this method needs further evaluation.

Late Failure of High-Flow Nasal Cannula May Be Associated with High Mortality in COVID-19 Patients: A Multicenter Retrospective Study in the Republic of Korea

The aim of this study was to determine whether the late failure of high-flow nasal cannula (HFNC) is associated with mortality in patients with coronavirus disease 2019 (COVID-19). This multicenter study included seven university-affiliated hospitals in the Republic of Korea. We collected the data of patients hospitalized with COVID-19 between 10 February 2020 and 28 February 2021. Failure of HFNC was defined as the need for mechanical ventilation despite HFNC application. According to the time of intubation, HFNC failure was divided into early failure (within 48 h) and late failure (after 48 h). During the study period, 157 patients received HFNC and 133 were eligible. Among them, 70 received mechanical ventilation. The median time from HFNC initiation to intubation of the early failure group was 4.1 h (interquartile range [IQR]: 1.1–13.5 h), and that of the late failure group was 70.9 h (IQR: 54.4–145.4 h). Although the ratio of pulse oximetry/fraction of inspired oxygen (ROX index) within 24 h of HFNC initiation tended to be lower in the early failure group than in the late failure group, the ROX index before two hours of intubation was significantly lower in the late failure group (odds ratio [OR], 5.74 [IQR: 4.58–6.98] vs. 4.80 [IQR: 3.67–5.97], p = 0.040). The late failure of HFNC may be associated with high mortality in COVID-19 patients with acute respiratory failure.

Factors associated with early and late digital revascularization and replantation failure: A retrospective cohort study

Factors associated with failure of digital revascularization and replantation procedures have been well characterized, but studies have not investigated failures occurring beyond the early postoperative period. A single-centre retrospective chart review included 284 patients (434 digits) who underwent digital revascularization or replantation. Patient-, injury- and surgery-related characteristics were compared among successful procedures, digits that failed while in hospital (early failure), and initially viable digits that failed after hospital discharge (late failure). Overall, 202 patients had successful procedures (71%). There were 51 early failures (18%) and 31 late failures (11%). Crush injuries and vein grafting were associated with early failure only. Complete amputations and leeching were strongly associated with both early and late failure. This study revealed that a substantial proportion of initially viable digits fail after discharge from hospital. Patients with signs of venous congestion may benefit from longer observation periods in hospital to avoid late failure. Level of evidence: IV

Comparison of postal and non-postal post-vasectomy semen sample submission strategies on compliance and failures: an 11-year analysis of the audit database of the Association of Surgeons in Primary Care of the UK

BackgroundVasectomy occlusive success is defined by the recommendation of ‘clearance’ to stop other contraception, and is elicited by post-vasectomy semen analysis (PVSA). We evaluated how the choice of either a postal or non-postal PVSA submission strategy was associated with compliance to PVSA and effectiveness of vasectomy.MethodsWe studied vasectomies performed in the UK from 2008 to 2019, reported in annual audits by Association of Surgeons in Primary Care members. We calculated the difference between the two strategies for compliance with PVSA, and early and late vasectomy failure. We determined compliance by adding the numbers of men with early failure and those given clearance. We performed stratified analyses by the number of test guidance for clearance (one-test/two-test) and the study period (2008–2013/2014–2019).ResultsAmong 58 900 vasectomised men, 32 708 (56%) and 26 192 (44%) were advised submission by postal and non-postal strategies, respectively. Compliance with postal (79.5%) was significantly greater than with non-postal strategy (59.1%), the difference being 20.4% (95% CI 19.7% to 21.2%). In compliant patients, overall early failure detection was lower with postal (0.73%) than with non-postal (0.94%) strategy (−0.22%, 95% CI −0.41% to −0.04%), but this difference was neither clinically nor statistically significant with one-test guidance in 2014–2019. There was no difference in late failure rates.ConclusionsPostal strategy significantly increased compliance to PVSA with similar failure detection rates. This resulted in more individuals receiving clearance or early failure because of the greater percentage of postal samples submitted. Postal strategy warrants inclusion in any future guidelines as a reliable and convenient option.

Hydrocephalus surveillance following shunt placement or endoscopic third ventriculostomy: a survey of surgeons in the Hydrocephalus Clinical Research Networks

OBJECTIVE Late failure is a well-documented complication of cerebrospinal fluid shunt placement and, less commonly, endoscopic third ventriculostomy (ETV). However, standards regarding the frequency of clinical and radiological follow-up in these patients have not been defined. Here, the authors report on their survey of surgeons at sites for the Hydrocephalus Clinical Research Network (HCRN) or its implementation/quality improvement arm (HCRNq) to provide a cross-sectional overview of practice patterns. METHODS A 24-question survey was developed using the Research Electronic Data Capture (REDCap) platform and was distributed to the 138 pediatric neurosurgeons across 39 centers who participate in the HCRN or HCRNq. Survey questions were organized into three sections: 1) Demographics (5 questions), 2) Shunt Surveillance (12 questions), and 3) ETV Surveillance (7 questions). RESULTS A total of 122 complete responses were obtained, for an overall response rate of 88%. The majority of respondents have been in practice for more than 10 years (58%) and exclusively treat pediatric patients (79%). Most respondents consider hydrocephalus to have stabilized 1 month (21%) or 3 months (39%) after shunt surgery, and once stability is achieved, 72% then ask patients to return for routine clinical follow-up annually. Overall, 83% recommend lifelong clinical follow-up after shunt placement. Additionally, 75% obtain routine imaging studies in asymptomatic patients, although the specific imaging modality and frequency of imaging vary. The management of an asymptomatic increase in ventricle size or an asymptomatic catheter fracture also varies widely. Many respondents believe that hydrocephalus takes longer to stabilize after ETV than after shunt placement, reporting that they consider hydrocephalus to have stabilized 3 (28%), 6 (33%), or 12 (28%) months after an ETV. Although 68% of respondents have patients return annually for routine clinical follow-up after an ETV, only 56% recommend lifelong follow-up. The proportion of respondents who perform lifelong follow-up increases with greater practice experience (p = 0.01). Overall, 67% of respondents obtain routine imaging studies in asymptomatic patients after an ETV, with “rapid” MRI the study of choice for most respondents. CONCLUSIONS While there is a general consensus among pediatric neurosurgeons across North America that hydrocephalus patients should have long-term follow-up after shunt placement, radiological surveillance is characterized by considerable variety, as is follow-up after an ETV. Future work should focus on evaluating whether any one of these surveillance protocols is associated with improved outcomes.

MO260PERFORMANCE ANALYSIS OF AN ARTIFICIAL NEURAL NETWORK TOOL TO PREDICT ESKD IN PATIENTS WITH IMMUNOGLOBULIN A NEPHROPATHY (IGAN)

Background During the last twenty years many tools, based on mathematical models, have been developed to predict ESKD at the time of kidney biopsy in patients with IgAN. The main limitation of these tools is the time frame to reach the ESKD. Recently, we have developed a Clinical Decision Support System (CDSS) (KI 2020) which includes 6 variables at the time of kidney biopsy: age, sex, hypertension, serum creatinine, daily proteinuria and score of the renal lesions according to the MEST-C classification. The tool (www.igan.poliba.it) is based on two different artificial neural networks of which the first predicts ESKD and the second one predicts the time to reach this outcome. Aim of our study has been to analyze the causes of discordance to predict or not ESKD in a cohort of 1116 IgAN patients (VALIGA cohort and external cohort) with a median follow-up of 88 months (49-135). To our knowledge this is the first report which analyzes the discrepant results of a toll to predict ESKD in IgAN patients. Method Demographic and laboratory data have been analyzed using means and standard deviations (SD) for continuous variables normally distributed, median in presence of non-normally distribution. Categorical variables are expressed as percentages. The means have been compared by the Student’s test and the medians using the Mann-Whitney U test. All the data were collected and stored in a standard Excel database. The statistical significance value p< 0.05 has been adopted. Results Discordance to reach or not ESKD was found in 216 patients (19.4%). In 77 patients with no prediction of ESKD, 25 patients with proteinuria > 0.5 g/day did not receive therapy after kidney biopsy or were cared very late. Failure of therapy (RASBs alone in 44 subjects and corticosteroids in 8 individuals) was observed in 52 patients. In 139 patients who did not reach ESKD but our tool predicted this outcome, interestingly, we found that 106 proteinuric patients (22 with GFR >50 ml/min/1.73 m2 and 84 with GFR < 50 ml/min/1.73 m2) had an improvement of the clinical course (reduction of proteinuria and stabilization of GFR value) after corticosteroid therapy. The remaining 33 patients benefited of RASB therapy. Among 84 patients with GFR< 50 ml/min/1.73 m2 36 had nephrotic proteinuria and were responsive to corticosteroids. These results suggest that we cannot rule out corticosteroid therapy in patients with reduced GFR and proteinuria > 3 g/day. Furthermore, our tool predicts the time frame to reach ESKD and indicates the potential effect of some drugs (RASBs, corticosteroids or their combination) to delay the outcome. We observed that corticosteroids combined with RASBs delayed more than 10 years the time to reach ESKD. Conclusions Our tool predicted ESKD in a percentage higher than that observed but, interestingly, it was found that a high number of patients benefited of corticosteroids in combination with RASBs. Furthermore, our tool predicted time to reach ESKD and indicated the potential benefit of therapy to delay the crude outcome. In fact, therapy delayed the outcome of more than 10 years when combination of corticosteroids and RASBs was administered. Therefore, our tool shows to physicians that their patients may delay the ESKD receiving corticosteroids alone or in combination with RASBs. This approach is important because in many cases it is a strengthen point to convince patients to accept the prescribed therapy. Moreover, this report shows for the first time that predicted ESKD may be delayed administering personalized therapy suggested by our tool. Essentially, in a high percentage of patients the failure of our tool is not an error but the positive effect of therapy or misconduct of patients management.

An Ex-Press implant versus trabeculectomy in a fibrotic bleb with late failure after previous trabeculectomy

AIM: To compare the outcome of an Ex-Press implant and subscleral trabeculectomy (SST) in the management of glaucoma after previous trabeculectomy on a fibrotic bleb. METHODS: This randomized prospective study included 28 eyes from 28 patients (age range: 42-55y) with primary open angle glaucoma (POAG) presented with elevated intraocular pressure (IOP) with fibrotic bleb despite previous SST for more than 4mo. The eyes enrolled in the study were divided into two groups: group I (subjected to Ex-Press implant surgery) and group II [subjected to SST with mitomycin C (MMC)]. The follow-up continued one year after surgery to evaluate IOP, visual acuity (VA), visual field (VF), and postoperative complications. RESULTS: A significant decrease in IOP was found in both groups with a higher reduction in Ex-Press implant surgery with the mean IOP of 14.50 mm Hg (P=0.001), while the SST group recorded the mean IOP of 16.50 mm Hg (P=0.001) after one year. However, the difference between the two groups in terms of the decrease in IOP was insignificant. Fewer postoperative complications were recorded in the Ex-Press implant surgery and more cases requiring further anti-glaucomatous medications were seen in the SST group. Both groups showed stability in terms of VA and VF. CONCLUSION: Ex-Press implant surgery and SST with MMC are two surgical alternatives for controlling IOP in late failure that occurs more than 4mo after previous SST with a fibrotic bleb. However, Ex-Press shunt is a safer surgery with fewer complications.

Managing Calcified Coronaries: the Bugaboo of Percutaneous Coronary Intervention

Background Percutaneous coronary intervention (PCI) of lesions with heavily coronary artery calcium (CAC) still represents a challenge for interventionists, with increased risk of immediate complications, late failure due to stent underexpansion and malapposition, and consequently poor clinical outcome. In this focused review, we provide the summary of principles, technique and contemporary evidence for various existing and emergent plaque modifying strategies. Main text PCI of lesions with heavy CAC still poses a challenge for the interventionists due to an increased risk of incomplete lesion preparation with subsequent suboptimal stent deployment and higher rates of acute and chronic stent failure. With the emergence of many novel devices and technologies, the treatment of lesions with heavy CAC has become increasingly feasible, safe and predictable. It seems likely that combining enhanced intravascular imaging modalities with traditional or new dedicated tools for the treatment of such lesions grant better lesion preparation. This optimizes delivery and deployment of drug-eluting stents translating into improved patient outcome. Conclusion The lesions with significant CAC are likely to surge due to aging population and increased rates of diabetes and chronic renal disease. The optimal therapy for such lesions is multi-adjunctive and requires the availability of several modalities including intracoronary imaging which could impact the clinical outcome favourably.