BACKGROUND:The Micra leadless pacemaker has demonstrated favorable outcomes in global trials, but its real-world performance and safety in a Japan-specific population is unknown. METHODS AND RESULTS:Micra Acute Performance (MAP) Japan enrolled 300 patients undergoing Micra VR leadless pacemaker implantation in 15 centers. The primary endpoint was the acute (30-day) major complication rate. The 30-day and 6-month major complication rates were compared to global Micra studies. All patients underwent successful implantation with an average follow-up of 7.23±2.83 months. Compared with previous Micra studies, Japanese patients were older, smaller, more frequently female, and had a higher pericardial effusion risk score. 11 acute major complications were reported in 10 patients for an acute complication rate of 3.33% (95% confidence interval: 1.61-6.04%), which was in line with global Micra trials. Pericardial effusion occurred in 4 patients (1.33%; 3 major, 1 minor). No procedure or device-related deaths occurred. Frailty significantly improved from baseline to follow-up as assessed by Japan Cardiovascular Health Study criteria. CONCLUSIONS:In a Japanese cohort, implantation of the Micra leadless pacemaker had a high success rate and low major complication rate. Despite the Japan cohort being older, smaller, and at higher risk, the safety and performance was in line with global Micra trials.

Background: Lead dislodgement (LD) has been one of the most common early complications after cardiovascular implantable electronic device implant. However, limited data are available on the clinical characteristics and long-term outcomes of LD events. The aim of this study was to examine the risk factors, clinical significance, and management strategies of LD events after cardiovascular implantable electronic device implant. Methods: This study was a retrospective cohort analysis of 20 683 patients who underwent cardiovascular implantable electronic device implant between January 1, 2010 and January 31, 2020 in Medtronic’s Product Surveillance Registry, with a mean follow-up time of 3.3±2.5 SD years. The study population was divided into 2 groups: group A with LD events (N=350) and group B without LD events (N=20 333). Results: During this period, 350 patients (1.69%) had LD events involving 371 leads (0.95%), among a total of 39 060 leads implanted. Passive fixation type (right atrium pacing lead, P=0.041), lower sensing amplitude (right ventricle defibrillating lead, P=0.020), and lower lead impedance at implant (right atrium pacing lead, P=0.009) were associated with increased LD risk. Multivariate analysis showed female sex (hazard ratio, 1.520, P=0.008) and higher body mass index (hazard ratio, 1.012, P=0.001) were independently associated with increased risk of LD events. LD events were not associated with significant changes in the long-term risks of cardiac and overall mortality. In group A, repositioning the dislodged leads increased the risk of a second LD event compared with implanting new leads (P=0.012). Conclusions: Female sex and higher body mass index were associated with higher risk of LD events in the Product Surveillance Registry. Among patients with dislodged leads, implanting new leads was associated with lower risk of future LD events. Further studies on how to reduce LD risk and to improve management of these events are needed. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01524276.

The implanted system for treprostinil has been described in previous publications. There is no information published about how to handle this system around lung or heart-lung transplantation. We present the experience from the DelIVery for Pulmonary Arterial Hypertension study. Seven subjects from five pulmonary arterial hypertension centers were included in this retrospective chart review. All subjects were participating in the previously described DelIVery for pulmonary arterial hypertension study. Seven subjects with implanted pumps have been listed for lung or heart-lung transplant. Six subjects underwent lung or heart-lung transplantation and one remains on the transplant list. Three different methods of patient management for transplant were used. In three subjects, the implanted system was filled with saline prior to transplantation and treprostinil was infused via an external system. Three subjects had their drug-filled implanted pump and catheter system explanted at the time of transplant. One patient had the drug-filled implanted system removed prior to being listed for transplantation. Four subjects were hospitalized while waiting for transplantation. In conclusion, the implanted system for treprostinil is an important advance in the care of pulmonary arterial hypertension subjects. The experience described here provides three effective strategies for managing the implanted system around lung or heart-lung transplantation. The optimal strategy will depend on patient characteristics and lung transplant program preferences and wait list times.

Lead dislodgement has been one of the most common early complications after cardiovascular implantable electronic device (CIED) implant. However, limited data is available on the clinical characteristics and outcomes of lead dislodgement events.

Background Many treatment protocols surrounding post-surgical pain management following total hip arthroplasty (THA) rely heavily on opioid medications and conventional formal physical therapy. We hypothesized that an expanded 90-day multimodal protocol could lead to a postoperative opioid-free or significantly reduced-opioid THA recovery with little or no need for formal physical therapy. Methods Prospective consecutive patients undergoing THA were enrolled in a 3 month long (6 weeks preoperatively and 6 weeks postoperatively) multimodal protocol including a robust education and optimization program with home-based physical therapy. All patients received a direct anterior approach THA on a Hana table by a single, fellowship-trained surgeon in a community practice. Opioid consumption was recorded at preoperative, postoperative, 3 week and 6 week timepoints. Results A total of 207 consecutive patients underwent THA and completed their 6-week follow-up evaluations. Seventy-nine patients (38%) required no opioid pills, 75 (36%) used 1-5 pills, 47 (23%) used 6-10 pills and 6 (3%) used more than ten pills. Overall 97% of patients undergoing DAA THA required 10 pills or less. Of those patients who reported taking at least one opioid pill, 92/128 (72%) took tramadol rather than stronger opioids. Average number of opioids was 3.5 pills per patient. Additionally, at 6 weeks, 95% of patients required no formal physical therapy. The percentage of patients discharged home the same day was 64% with 94% home by POD #1. Average length of stay was .42 days. Conclusion This study confirms that an expanded length multimodal protocol can significantly reduce or eliminate opioid consumption following outpatient DAA THA. It additionally confirms that the majority of patients may do well with a simple home exercise program.

Background Interest in direct anterior approach (DAA) has increased over the last decade. In our previously published study comparing DAA to posterolateral approach (PA), early 3-month benefits were noted in terms of pain and function. There was no difference noted at 6 or 12 months. This study reports average 5-year follow-up of our original study. Methods Originally there were 43 DAA patients and 44 PA patients. At an average 5-year follow-up, patients were evaluated clinically with a University of California at Los Angeles activity score, Harris hip score, and Hip Disability and Osteoarthritis Outcome Score Jr Survivorship analysis was calculated. Radiographs were evaluated for loosening and evidence of radiolucent lines. Results There were 2 deaths 1 in each group, neither was related to the implant or procedure. Four patients were lost to follow-up: 2 in the DAA group and 2 in the PA group. There was no statistical difference between surgical approaches in terms of Harris hip score, University of California at Los Angeles activity score, and Hip Disability and Osteoarthritis Outcome Score Jr. The 7-year survivorship was not significantly different. There were no loose implants at average 5-year follow-up. Conclusion Both DAA and PA yield good results at an average 5-year follow-up in terms of survivorship, function, rate of complications, and radiographic analysis.

BACKGROUND: Cerebrospinal fluid (CSF) shunt infection is a major cause of morbidity and mortality in the treatment of hydrocephalus and is associated with significant medical cost. Several studies have demonstrated the efficacy of antibiotic-impregnated (AI) shunt catheters in reducing CSF shunt infection; however, providers remain reluctant to adopt AI catheters into practice because of the increased upfront cost. The objective of this study was to determine if the use of AI catheters provided cost savings in a large nationwide database.METHODS: Hospital discharge and billing records from the Premier Perspective Database from 2003-2009 were retrospectively reviewed to identify all adult and pediatric patients undergoing de novo ventricular shunt placement. The incidence of shunt infection within 1 year of implantation was determined. Shunt infection-related cost was defined as all inpatient billing costs incurred during hospitalization for treatment of shunt infection.RESULTS: In 287 U.S. hospitals, 10,819 adult (AI catheters, 963; standard catheters, 9856) and 1770 pediatric (AI catheters, 229; standard catheters, 1541) patients underwent ventricular shunt placement. AI catheters were associated with significant reduction in infection for both adult (2.2% vs. 3.6%, P=0.02) and pediatric (2.6% vs. 7.1%, P < 0.01) patients. Total infection-related costs were $ 17,371,320 ($ 45,714 +/- $ 49,745 per shunt infection) for adult patients and $ 6,508,064 ($ 56,104 +/- $ 65,746 per shunt infection) for pediatric patients. Infection-related cost per 100 de novo shunts placed was $ 120,534 for AI catheters and $ 162,659 for standard catheters in adult patients and $ 165,087 for AI catheters and $ 395,477 for standard catheters in pediatric patients.CONCLUSIONS: In analysis of this large, nationwide database, AI catheters were found to be associated with a significant reduction in infection incidence, resulting in tremendous cost savings. AI catheters were associated with a cost savings of $ 42,125 and $ 230,390 per 100 de novo shunts placed in adult and pediatric patients, respectively.

Cross-linked bearings have been developed for use in total knee arthroplasty that exhibit improved wear properties, but at the expense of a decrease in mechanical strength of the cross-linked material. Adoption has been slow due to fears of mechanical failure secondary to this alteration in mechanical properties. This prospective, randomized study compared mid-term survivorship, clinical and radiographic results of a conventional polyethylene (GVF) to a cross-linked polyethylene (XLK) in total knee prostheses of the same design. At minimum 5-year follow-up there was no difference in survivorship, clinical performance or radiographic findings between the groups. There were no revisions for polyethylene wear, osteolysis or tibial insert dissociation. Most importantly, there were no revisions for mechanical failure or fracture of the polyethylene bearing in either group.

OBJECTThe real-world effectiveness of antibiotic-impregnated shunt catheters to reduce the incidence of shunt infections is still debated. The literature to date consists mostly of small, single-institution studies. The aim of this study was to assess the incidence of infection for antibiotic-impregnated catheters (AICs) versus standard shunt catheters in a large nationwide administrative database.METHODSThe authors retrospectively reviewed hospital discharge and billing records from the Premier Perspective Database from April 2003 to July 2009 to identify all adult and pediatric patients undergoing de novo ventricular shunt placement. The primary end point was the incidence of shunt infection within 1 year of implantation. Multivariate logistical regression was performed to determine factors associated with increased incidence of infection.RESULTSA total of 10,819 adult (AIC, 963; standard catheter, 9856) and 1770 pediatric (AIC, 229; standard catheter, 1541) patients underwent ventricular shunt placement in 287 US hospitals. Overall, the incidence of infection was 3.5% in adults (n=380) and 6.6% in pediatric patients (n=116). AICs were associated with significant reduction in infection for both adult (2.2% vs 3.6%, p=0.02) and pediatric (2.6% vs 7.1%, p<0.01) patients. AIC use was associated with reduced infection regardless of hospital size, annual shunt volume, hospital location, or patient risk factors and remained associated with a reduced infection in multivariate analysis for both adult (p=0.02) and pediatric (p=0.02) patients.CONCLUSIONSThe use of antibiotic-impregnated shunt catheters was associated with a reduction in shunt infections for both adult and pediatric patients. This provides further support that AICs may represent a reliable means of reducing shunt infections for both adult and pediatric patients.

Patient specific instrumentation (PSI) was developed to increase total knee arthroplasty (TKA) accuracy and efficiency. The study purpose was to compare immediate post-operative mechanical alignment, achieved using PSI, with conventional and computer assisted surgery (CAS) instruments in high volume TKA practices. This prospective, multicenter, non-randomized study accrued 66 TKA patients using PSI. A computed tomography (CT) based algorithm was used to develop the surgical plan. Sixty-two percent were females, 99% were diagnosed with osteoarthritis, average age at surgery was 66 years, and 33 was the average body mass index. A historical control group was utilized that underwent TKA using conventional instruments (n=86) or CAS (n=81), by the same set of surgeons. Postoperative mechanical alignment was comparable across the groups. Operative time mean and variance were significant.

From March 2006 to August 2008, 93 subjects (186 knees) underwent simultaneous bilateral total knee arthroplasty performed by eight surgeons at North American centers. This randomized study was conducted to determine whether non-weight-bearing passive flexion was superior for knees receiving a posterior stabilized high flexion device compared to a posterior stabilized standard device in the contra-lateral knee. Weight-bearing single leg active flexion was one secondary endpoint. Follow-up compliance was 92.5%. Results show small, but significant superiority in the motion metrics for the high flexion device compared to the standard device 12 months after surgery, especially for a subgroup of patients with pre-operative flexion less than 120° in both knees. Thus, the ideal candidate for the high flexion device may be one with lesser pre-operative flexion.

BACKGROUND:External ventricular drainage (EVD) catheters provide reliable and accurate means of monitoring intracranial pressure and alleviating elevated pressures via drainage of cerebrospinal fluid (CSF). CSF infections occur in approximately 9% of patients. Antibiotic-impregnated (AI) EVD catheters were developed with the goal of reducing the occurrence of EVD catheter-related CSF infections and their associated complications. OBJECTIVE:To present an international, prospective, randomized, open-label trial to evaluate infection incidence of AI vs standard EVD catheters. METHODS:Infection was defined as (1) proven infection, positive CSF culture and positive Gram stain or (2) suspected infection: (A) positive CSF culture with no organisms identified on initial Gram stain; (B) negative CSF culture with a gram-positive or -negative stain; (C) CSF leukocytosis with a white blood cell/red blood cell count >0.02. RESULTS:Four hundred thirty-four patients underwent implantation of an EVD catheter. One hundred seventy-six patients in the AI-EVD cohort and 181 in the standard EVD catheter cohort were eligible for evaluation of infection. The 2 groups were similar in all clinical characteristics. Proven infection was documented in 9 (2.5%) patients (AI: 4 [2.3%] vs standard: 5 [2.8%], P = 1.0). Suspected infection was documented in 31 (17.6%) patients receiving AI and 37 (20.4%) patients receiving standard EVD catheters, P = .504. Duration of time to suspected infection was prolonged in the AI cohort (8.8 ± 6.1 days) compared with the standard EVD cohort (4.6 ± 4.2 days), P = .002. CONCLUSION:AI-EVD catheters were associated with an extremely low rate of catheter-related infections. AI catheters were not associated with risk reduction in EVD infection compared to standard catheters. Use of AI-EVD catheters is a safe option for a wide variety of patients requiring CSF drainage and monitoring, but the efficacy of AI-EVD catheters was not supported in this trial.

Early post-operative clinical outcomes were analyzed for subjects having a rotating platform (RP) posterior stabilized (PS) total knee arthroplasty (TKA); a subset of which underwent in vivo kinematics and produced kinematic results that compare well with subjects in previous fluoroscopic studies that were deemed excellent in nature. In total, 153 subjects (180 knees) were enrolled in the prospective clinical study. TKAs were performed by three surgeons at three North American centers. Ten subjects were randomly chosen and evaluated under fluoroscopic surveillance. Average active flexion increased from 113.3 (SD=16.6) degrees before surgery to 118.3 (SD=9.9) degrees 12-months post-operatively. American Knee Society (AKS) function score increased from an average of 57.6 (SD=18.8) points pre-operatively to 85.3 (SD=16.6) points 12-months post-operatively. For the kinematic subset, post-operative weight-bearing flexion was 115.9 (SD=8.4),while subjects achieved an average posterior femoral rollback of their lateral condyle of −5.4 mm. The average femorotibial axial rotation from full extension to maximum weight-bearing flexion was 3.9 degrees (SD=3.9). Certain kinematic parameters were deemed statistically significant when determining early post-operative clinical success.

Interest in mobile-bearing knee prostheses is increasing in the US market. We studied results at 2 to 5 years with a mobile-bearing system that includes a cobalt-chrome tibial tray and femoral component with a polyethylene cruciate-retaining tibial component insert that allows rotation around a central axis and can be used with cruciate-retaining or posterior-stabilized femoral components. The inserts used in this study were cruciate retaining and did not include the posterior-stabilized design. The goal of this study was to demonstrate the function and safety of this prosthesis along with the lack of spinout, which is a major concern in the mobile-bearing knee. Four hundred thirty-five knees constituted the study cohort and underwent survivorship analysis and complication reporting. Routine clinic evaluations included pre- and postoperative radiographs and Knee Society knee and function scores at 6 and 12 weeks and every 2 years. The most recent follow-up data within 2 to 5 years was included for the study along with survey data. Flexion at most recent follow-up averaged 125°. Knee Society score at most recent visit averaged 88 of 100. Knee Society function score averaged 83 of 100. Radiographic results were available for 226 knees, with 97.3% assessed as normal and 6 with these issues: patella stress fracture (3), aseptic tibial loosening (1), patellar osteolysis (1), and patella aseptic loosening (1). In comparison with the fixed-bearing knee equivalent, this mobile-bearing knee demonstrated at least equivalent results in terms of survivorship, function, and patient satisfaction in the short- and mid-term.

Gender-specific total knee replacement has generated much interest recently. We reviewed 1970 Sigma knees implanted in 920 women and 592 men with a mean age of 69.7 years. At a mean follow-up of 7.3 years (minimum, five years), we found minimal differences in the outcome between genders. At the final follow-up, men had a higher overall Knee Society score and more osteolysis (3.8% vs 1.1%). However, there were no significant differences between men and women in terms of complications or improvements in knee function, pain score or range of movement. The estimated ten-year survivorship was 97% in women and 98% in men (p = 0.96). We concluded that there was little difference in outcome between the genders treated by a modern unisex design of total knee replacement in this large multicentre study.

Although the published studies on the outcomes of total hip arthroplasty (THA) performed with currently available ceramic components show high survivorship and low bearing wear at midterm followup, concern over ceramic fracture and squeaking persist. For these reasons, the use of ceramic is limited. Recently, a new alumina matrix composite material (Delta ceramic) with improved material properties was developed to address these concerns. We report the early outcomes and complications of a prospective, randomized, multicenter trial of 263 patients (264 hips) at eight centers, comparing a Delta ceramic-on-ceramic (COC) articulation with a Delta ceramic head-crosslinked polyethylene bearing combination (COP). There were 177 COC hips and 87 COP hips. Complications were reported for all patients, whereas clinical and radiographic results were provided for the 233 patients with minimum 2-year followup (average, 31.2 months; range, 21–49 months). The Harris hip scores and clinical, radiographic, and survivorship outcomes were similar in both groups. There were four (2%) revisions in the COC group and two (2%) in the COP group. We encountered three intraoperative ceramic liner-related events. In addition, one patient receiving the COC underwent revision for chipping of the ceramic liner, and a second had ceramic fragmentation on followup radiographs but has not undergone revision. These liner related complications remain a concern. No patient reported squeaking in either group; this leaves us hopeful the new material will lessen the frequency of squeaking. In the short term, the Delta COC articulation provided similar functional scores and survivorship and complication rates with the ceramic head mated with crosslinked polyethylene.

This retrospective study evaluated the midterm clinical and radiographic outcomes of a second-generation total knee replacement system. In a multicentre consecutive series of 1512 patients, 1970 knees were treated with the PFC Sigma knee system (Depuy, Warsaw, Indiana). The patients were reviewed for functional outcome, and underwent independent radiographic evaluation at a mean follow-up of 7.3 years (5 to 10). A total of 40 knees (2%) required revision, 17 (0.9%) for infection. The incidence of osteolysis was 2.2%. The ten-year survival with revision for any cause other than infection as the endpoint was 97.2% (95% CI 95.4 to 99.1). The PFC Sigma knee system appears to provide excellent results in the medium term.

This study compared the rate of wear-related failure between 2 large series of total knees using identical modular tibial trays and polyethylene inserts sterilized by different methods.

This study compared the midterm results of an all-polyethylene (AP) with a metal-backed (MB) modular tibial component with identical surface geometries. This is a retrospective, matched subset of patients evaluated by an independent radiographer.