Remote Acute Assessment of Cardiac Patients Post-Acute Coronary Syndrome (TELE-ACS): A Randomized Controlled Trial.

BACKGROUND: Telemedicine programmes can provide remote diagnostic information to aid clinical decision that could optimize care and reduce unplanned re-admissions post ACS. OBJECTIVES: TELE-ACS is a randomized controlled trial which aims to compare a telemedicine-based approach versus standard care in patients following ACS. METHODS: Patients were suitable for inclusion with at least one cardiovascular risk factor and presenting with ACS and were randomized (1:1) prior to discharge. The primary outcome was time to first readmission at 6-months. Secondary outcomes included emergency department (ED) visits, major adverse cardiovascular events and patient reported symptoms. The primary analysis was performed according to intention to treat. The trial was registered on ClinicalTrial.gov (NCT05015634). RESULTS: 337 patients were randomized from January 2022 to April 2023, with a 3.6% drop-out rate. The mean age was 58.1 years. There was a reduced rate of readmission over 6-months (hazard ratio [HR] 0.24; 95% confidence interval [CI] 0.13 to 0.44; p < 0.001) and ED attendance (HR 0.59; 95% CI 0.59; 95% CI 0.40 to 0.89) in the telemedicine arm, and fewer unplanned coronary revascularizations (3% in telemedicine arm versus 9% in standard therapy arm). The occurrence of chest pain (9% versus 24%), breathlessness (21% versus 39%) and dizziness (6% versus 18%) at 6-months was lower in the telemedicine group. CONCLUSIONS: The TELE-ACS study has shown that a telemedicine-based approach for the management of patients following ACS was associated with a reduction in hospital readmission, ED visits, unplanned coronary revascularization and patient reported symptoms.

Physiological Assessment with iFR prior to FFR Measurement in Left Main Disease.

Despite guideline-based recommendation of the interchangeable use of instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR) to guide revascularization decision-making, iFR/FFR could demonstrate different physiological or clinical outcomes in some specific patient or lesion subsets. Therefore, we sought to investigate the impact of difference between iFR and FFR-guided revascularization decision-making on clinical outcomes in patients with left main disease (LMD). In this international multicenter registry of LMD with physiological interrogation, we identified 275 patients in whom physiological assessment was performed with both iFR/FFR. Major adverse cardiovascular event (MACE) was defined as a composite of death, non-fatal myocardial infarction, and ischemia-driven target lesion revascularization. The receiver-operating characteristic analysis was performed for both iFR/FFR to predict MACE in respective patients in whom revascularization was deferred and performed. In 153 patients of revascularization deferral, MACE occurred in 17.0% patients. The optimal cut-off values of iFR and FFR to predict MACE were 0.88 (specificity:0.74; sensitivity:0.65) and 0.76 (specificity:0.81; sensitivity:0.46), respectively. The area under the curve (AUC) was significantly higher for iFR than FFR (0.74; 95%CI 0.62-0.85 vs. 0.62; 95%CI 0.48-0.75; p = 0.012). In 122 patients of coronary revascularization, MACE occurred in 13.1% patients. The optimal cut-off values of iFR and FFR were 0.92 (specificity:0.93; sensitivity:0.25) and 0.81 (specificity:0.047; sensitivity:1.00), respectively. The AUCs were not significantly different between iFR and FFR (0.57; 95%CI 0.40-0.73 vs. 0.46; 95%CI 0.31-0.61; p = 0.43). While neither baseline iFR nor FFR was predictive of MACE in patients in whom revascularization was performed, iFR-guided deferral seemed to be safer than FFR-guided deferral.

Automated echocardiographic left ventricular dimension assessment in dogs using artificial intelligence: Development and validation.

BACKGROUND: Artificial intelligence (AI) could improve accuracy and reproducibility of echocardiographic measurements in dogs. HYPOTHESIS: A neural network can be trained to measure echocardiographic left ventricular (LV) linear dimensions in dogs. ANIMALS: Training dataset: 1398 frames from 461 canine echocardiograms from a single specialist center. VALIDATION: 50 additional echocardiograms from the same center. METHODS: Training dataset: a right parasternal 4-chamber long axis frame from each study, labeled by 1 of 18 echocardiographers, marking anterior and posterior points of the septum and free wall. VALIDATION DATASET: End-diastolic and end-systolic frames from 50 studies, annotated twice (blindly) by 13 experts, producing 26 measurements of each site from each frame. The neural network also made these measurements. We quantified its accuracy as the deviation from the expert consensus, using the individual-expert deviation from consensus as context for acceptable variation. The deviation of the AI measurement away from the expert consensus was assessed on each individual frame and compared with the root-mean-square-variation of the individual expert opinions away from that consensus. RESULTS: For the septum in end-diastole, individual expert opinions deviated by 0.12 cm from the consensus, while the AI deviated by 0.11 cm (P = .61). For LVD, the corresponding values were 0.20 cm for experts and 0.13 cm for AI (P = .65); for the free wall, experts 0.20 cm, AI 0.13 cm (P < .01). In end-systole, there were no differences between individual expert and AI performances. CONCLUSIONS AND CLINICAL IMPORTANCE: An artificial intelligence network can be trained to adequately measure linear LV dimensions, with performance indistinguishable from that of experts.

An analysis of direct and indirect costs in Hidradenitis Suppurativa.

Background: Hidradenitis Suppurativa (HS) is a chronic inflammatory skin condition with recurrent nodules and abscesses that culminate in purulent discharge and scarring. It has significant physical, psychological and financial impact. Objectives: This study plans to analyse patient costs associated with HS. Direct costs include prescription items. Indirect or out-of-pocket costs include dressings, analgesia, and healthcare-related travel costs. This study will also assess disease impact on quality-of-life (QOL). Methods: Patients with HS diagnosis attending dermatology OPD at our public tertiary centre were invited to participate. Ethical approval was secured, and informed consent was obtained. Participants completed an anonymous survey which was analysed to identify costs associated with HS as well as demographics and QOL impact. Results: A total of 25 patients completed the survey; median age was 29% and 80% were female. Median time from HS onset to diagnosis was 2 years, with 24% waiting >10 years to be diagnosed. In the past 3 months, 20% spent >€200 in both categories; prescription and non-prescription items. In the non-prescription category, 36% of patients reported expenditure >€100 in the past 3 months. Dressings were the most common out-of-pocket expense (in 15/25 patients), followed by analgesia and protective clothing. Attendance at medical appointments cost 24% of patients €50-€200. Four participants reported difficulty accessing HS treatments due to associated costs. Mean number of absence days from work/education as result of HS was 8.7 in the past 3 months. Two patients reported being on disability allowance, and two on unemployment benefit as result of their skin disorder. In the QOL question; 96% reported disease impact on QOL, and 11 participants reported that it affected their life 'very much'. Conclusions: HS is a chronic inflammatory skin condition with significant financial burden alongside the well-analysed biopsychosocial disease impact. Financial burden can be divided into direct prescription costs and indirect costs such as non-prescription items, protective clothing and travel costs which we have explored in this study. Further research is needed in this area to identify and optimise both the financial and QOL implications of HS in acute flares and chronic disease management.

Aortic stenosis assessment from the 3-chamber cine: Ratio of balanced steady-state-free-precession (bSSFP) blood signal between the aorta and left ventricle predicts severity.

BACKGROUND: Cardiovascular magnetic resonance (CMR) imaging is an important tool for evaluating the severity of aortic stenosis (AS), co-existing aortic disease, and concurrent myocardial abnormalities. Acquiring this additional information requires protocol adaptations and additional scanner time, but is not necessary for the majority of patients who do not have AS. We observed that the relative signal intensity of blood in the ascending aorta on a balanced steady state free precession (bSSFP) 3-chamber cine was often reduced in those with significant aortic stenosis. We investigated whether this effect could be quantified and used to predict AS severity in comparison to existing gold-standard measurements. METHODS: Multi-centre, multi-vendor retrospective analysis of patients with AS undergoing CMR and transthoracic echocardiography (TTE). Blood signal intensity was measured in a ∼1 cm2 region of interest (ROI) in the aorta and left ventricle (LV) in the 3-chamber bSSFP cine. Because signal intensity varied across patients and scanner vendors, a ratio of the mean signal intensity in the aorta ROI to the LV ROI (Ao:LV) was used. This ratio was compared using Pearson correlations against TTE parameters of AS severity: aortic valve peak velocity, mean pressure gradient and the dimensionless index. The study also assessed whether field strength (1.5 T vs. 3 T) and patient characteristics (presence of bicuspid aortic valves (BAV), dilated aortic root and low flow states) altered this signal relationship. RESULTS: 314 patients (median age 69 [IQR 57-77], 64% male) who had undergone both CMR and TTE were studied; 84 had severe AS, 78 had moderate AS, 66 had mild AS and 86 without AS were studied as a comparator group. The median time between CMR and TTE was 12 weeks (IQR 4-26). The Ao:LV ratio at 1.5 T strongly correlated with peak velocity (r = -0.796, p = 0.001), peak gradient (r = -0.772, p = 0.001) and dimensionless index (r = 0.743, p = 0.001). An Ao:LV ratio of < 0.86 was 84% sensitive and 82% specific for detecting AS of any severity and a ratio of 0.58 was 83% sensitive and 92% specific for severe AS. The ability of Ao:LV ratio to predict AS severity remained for patients with bicuspid aortic valves, dilated aortic root or low indexed stroke volume. The relationship between Ao:LV ratio and AS severity was weaker at 3 T. CONCLUSIONS: The Ao:LV ratio, derived from bSSFP 3-chamber cine images, shows a good correlation with existing measures of AS severity. It demonstrates utility at 1.5 T and offers an easily calculable metric that can be used at the time of scanning or automated to identify on an adaptive basis which patients benefit from dedicated imaging to assess which patients should have additional sequences to assess AS.

A multimodal assessment of cementless tibial baseplate fixation using radiography, radiostereometric analysis, and magnetic resonance imaging.

Fixation in cementless total knee arthroplasty is provided by osseous integration. Radiography, radiostereometric analysis (RSA), and magnetic resonance imaging (MRI) were used simultaneously to investigate fixation. Relationships between RSA-measured implant micromotions and MRI-evaluated osseous integration at the component-bone interface were assessed in 10 patients up to 6 months postoperation. Supine MRI (using multispectral imaging sequences) and RSA exams were performed to evaluate osseous integration and measure longitudinal migration, respectively. Inducible displacement was measured from standing RSA exams. Radiolucent lines were detected on conventional radiographs. Of 10 patients, 6 had fibrous membranes detected on MRI. No fluid or osteolytic interfaces were found, and no components were scored loose. Of 10 patients, 6 had radiolucent lines detected. Average maximum total point motion (MTPM) for longitudinal migration at 6 months was 0.816 mm (range 0.344-1.462 mm). Average MTPM for inducible displacement at 6 months was 1.083 mm (range 0.553-1.780 mm). Fictive points located in fibrous-classified baseplate quadrants had greater longitudinal migration than fictive points located in baseplate quadrants with normal interfaces at 2 weeks (p = 0.031), 6 weeks (p = 0.046), and 3 months (p = 0.047), and greater inducible displacements at 3 months (p = 0.011) and 6 months (p = 0.045). Greater early micromotion may be associated with the presence of fibrous membranes at the component-bone interface. Clinical significance: This multimodal imaging study contributes knowledge of the fixation of modern cementless TKA, supporting the notion that osseous integration is important for optimal implant fixation.

Commercially available wearable health monitor in dogs is unreliable for tracking energy intake and expenditure.

OBJECTIVE: Assess the accuracy of predicted daily energy requirement (pDER) reported by a triaxial accelerometer and activity monitor for dogs (FitBark 2; FitBark Inc) and determine whether the activity monitor accurately estimates the observed daily energy requirement (oDER). We hypothesized that the activity monitor would accurately estimate oDER in dogs and meet standards established for human devices. ANIMALS: 23 dogs between the ages of 1 and 10 years and variable sex, breed, and body weight were enrolled from May 5, 2021, through July 23, 2021. METHODS: Dogs were weighed before and after the study period to ensure stable body weights. Owners recorded their dogs' daily caloric intake for the entire 28-day study period while the device monitored physical activity and calculated pDER. oDER was defined as the reported caloric intake required to maintain a stable body weight over a 28-day period. pDER and oDER were compared using Bland-Altman graphs, Passing-Bablock analysis, and Lin's Concordance correlation analysis. P ≤ .05 was considered significant. RESULTS: 23 apparently healthy dogs completed the study. There was no significant difference between starting body weights and ending body weights (P= .5). The activity monitor overpredicted 28-day pDER compared to 28-day oDER in the majority (18/23, 78.3%) of dogs. Based on Bland-Altman analysis, Passing-Bablok regression, and Lin's concordance correlation analysis, there was poor agreement between the pDER and oDER. CLINICAL RELEVANCE: The activity monitors consistently reported inaccurate pDER compared to oDER. Its usability for estimating pDER is of limited clinical and research utility based on the results of this study.

Racial and Socioeconomic Equity of Tecovirimat Treatment during the 2022 Mpox Emergency, New York, New York, USA.

We assessed tecovirimat treatment equity for 3,740 mpox patients in New York, New York, USA, during the 2022 mpox emergency; 32.4% received tecovirimat. Treatment rates by race/ethnicity were 38.8% (White), 31.3% (Black/African American), 31.0% (Hispanic/Latino), and 30.1% (Asian/Pacific Islander/other). Future public health emergency responses must prioritize institutional and structural racism mitigation.

The economic burden of individuals living with generalized myasthenia gravis and facing social determinants of health challenges.

Objective: Better understanding the impact of social determinants of health (SDOH) barriers from the patient perspective is crucial to improve holistic patient support in generalized myasthenia gravis (gMG), a rare autoimmune disorder with high disease and treatment burden. The objective of this study was to identify economic challenges experienced by individuals living with gMG and SDOH barriers to better address current unmet needs. Methods: Adults (18-75 years) living with gMG and experiencing SDOH barriers in the United States were recruited to a mixed-methods study including qualitative interviews and a web-based quantitative survey. Quotas were implemented to include a balanced spread of baseline demographic categories including insurance type, living environment, and employment status among the study sample. Direct and indirect economic challenges were identified by degree of concern. Results: The survey was completed by 38 individuals living with gMG, the majority of whom were enrolled in public insurance and not employed. The most commonly reported major economic concerns were managing funds for emergency care (66%), loss of income (61%), and non-medical expenses (58%), highlighting the diversity of economic challenges. Individuals who were using public insurance plans, living in non-urban environments, and unemployed experienced pronounced challenges around managing non-medical costs and accessing government assistance. Conclusion: Both direct and indirect costs were emphasized as major concerns among individuals living with gMG and SDOH barriers. Increasing access to relevant, personalized, and holistic resources, including care management, should be prioritized to improve disease management and outcomes for individuals living with gMG.

Development of artificial intelligence tools for invasive Doppler-based coronary microvascular assessment.

Aims: Coronary flow reserve (CFR) assessment has proven clinical utility, but Doppler-based methods are sensitive to noise and operator bias, limiting their clinical applicability. The objective of the study is to expand the adoption of invasive Doppler CFR, through the development of artificial intelligence (AI) algorithms to automatically quantify coronary Doppler quality and track flow velocity. Methods and results: A neural network was trained on images extracted from coronary Doppler flow recordings to score signal quality and derive values for coronary flow velocity and CFR. The outputs were independently validated against expert consensus. Artificial intelligence successfully quantified Doppler signal quality, with high agreement with expert consensus (Spearman's rho: 0.94), and within individual experts. Artificial intelligence automatically tracked flow velocity with superior numerical agreement against experts, when compared with the current console algorithm [AI flow vs. expert flow bias -1.68 cm/s, 95% confidence interval (CI) -2.13 to -1.23 cm/s, P < 0.001 with limits of agreement (LOA) -4.03 to 0.68 cm/s; console flow vs. expert flow bias -2.63 cm/s, 95% CI -3.74 to -1.52, P < 0.001, 95% LOA -8.45 to -3.19 cm/s]. Artificial intelligence yielded more precise CFR values [median absolute difference (MAD) against expert CFR: 4.0% for AI and 7.4% for console]. Artificial intelligence tracked lower-quality Doppler signals with lower variability (MAD against expert CFR 8.3% for AI and 16.7% for console). Conclusion: An AI-based system, trained by experts and independently validated, could assign a quality score to Doppler traces and derive coronary flow velocity and CFR. By making Doppler CFR more automated, precise, and operator-independent, AI could expand the clinical applicability of coronary microvascular assessment.

Smartphone-Based Remote Monitoring in Heart Failure With Reduced Ejection Fraction: Retrospective Cohort Study of Secondary Care Use and Costs.

BACKGROUND: Despite effective therapies, the economic burden of heart failure with reduced ejection fraction (HFrEF) is driven by frequent hospitalizations. Treatment optimization and admission avoidance rely on frequent symptom reviews and monitoring of vital signs. Remote monitoring (RM) aims to prevent admissions by facilitating early intervention, but the impact of noninvasive, smartphone-based RM of vital signs on secondary health care use and costs in the months after a new diagnosis of HFrEF is unknown. OBJECTIVE: The purpose of this study is to conduct a secondary care health use and health-economic evaluation for patients with HFrEF using smartphone-based noninvasive RM and compare it with matched controls receiving usual care without RM. METHODS: We conducted a retrospective study of 2 cohorts of newly diagnosed HFrEF patients, matched 1:1 for demographics, socioeconomic status, comorbidities, and HFrEF severity. They are (1) the RM group, with patients using the RM platform for >3 months and (2) the control group, with patients referred before RM was available who received usual heart failure care without RM. Emergency department (ED) attendance, hospital admissions, outpatient use, and the associated costs of this secondary care activity were extracted from the Discover data set for a 3-month period after diagnosis. Platform costs were added for the RM group. Secondary health care use and costs were analyzed using Kaplan-Meier event analysis and Cox proportional hazards modeling. RESULTS: A total of 146 patients (mean age 63 years; 42/146, 29% female) were included (73 in each group). The groups were well-matched for all baseline characteristics except hypertension (P=.03). RM was associated with a lower hazard of ED attendance (hazard ratio [HR] 0.43; P=.02) and unplanned admissions (HR 0.26; P=.02). There were no differences in elective admissions (HR 1.03, P=.96) or outpatient use (HR 1.40; P=.18) between the 2 groups. These differences were sustained by a univariate model controlling for hypertension. Over a 3-month period, secondary health care costs were approximately 4-fold lower in the RM group than the control group, despite the additional cost of RM itself (mean cost per patient GBP £465, US $581 vs GBP £1850, US $2313, respectively; P=.04). CONCLUSIONS: This retrospective cohort study shows that smartphone-based RM of vital signs is feasible for HFrEF. This type of RM was associated with an approximately 2-fold reduction in ED attendance and a 4-fold reduction in emergency admissions over just 3 months after a new diagnosis with HFrEF. Costs were significantly lower in the RM group without increasing outpatient demand. This type of RM could be adjunctive to standard care to reduce admissions, enabling other resources to help patients unable to use RM.

Ultrasound-Guided Motor-Sparing Knee Blocks for Postoperative Analgesia Following Total Knee Arthroplasty: A Cost Analysis.

Background: We recently performed a clinical trial comparing motor sparing blocks (MSB) to periarticular infiltration (PAI) following total knee arthroplasty (TKA). We found that MSBs provided longer analgesia (8.8 hours) than PAI with retention of quadriceps strength, and with similar function, satisfaction, and length hospital stay. However, its potential increased cost could serve as a barrier to its adoption. Therefore, our aim was to compare the costs of MSBs to PAI following TKA. Methods: We conducted a retrospective review of data from our previous RCT. There were 82 patients included in the RCT (n = 41 MSB group, n = 41 PAI group). We compared the mean total costs associated with each group until hospital discharge including intervention costs, health-care professional service fees, intraoperative medications, length of stay, and postoperative opioid use. Results: Seventy patients were included (n = 35 MSB group, n = 35 PAI group). The mean total costs for the MSB group were significantly higher ($1959.46 ± 755.4) compared to the PAI group ($1616.25 ± 488.33), with a mean difference of $343.21 (95% CI = $73.28 to $664.11, p = 0.03). The total perioperative intervention costs for performing the MSB was also significantly higher; however, postoperative inpatient costs including length of stay and total opioid use did not differ significantly. Conclusion: Motor sparing blocks had significantly higher mean total and perioperative costs compared to PAI with no significant difference in postoperative inpatient costs. However, its quadricep sparing nature and previously demonstrated prolonged postoperative analgesia can be used to facilitate an outpatient TKA pathway thereby offsetting its increased costs.

Conservative nonsurgical treatment for cranial cruciate ligament disease can be an effective management strategy in cats based on validated owner-based subjective assessment in some cases.

OBJECTIVE: To describe long-term outcomes of cats managed medically for cranial cruciate ligament disease (CCLD) via a validated owner-based questionnaire. ANIMALS: 18 client-owned cats. PROCEDURES: Retrospective review of medical records at 2 tertiary referral hospitals was conducted for records of cats diagnosed with CCLD for which medical management was pursued. History, physical examination findings, and medical management strategies were recorded. Owner follow-up was obtained via phone call or an email correspondence interview using a 2-part questionnaire. Part 1 consisted of 5 multiple-choice questions evaluating short-term outcomes following initiation of medical management. Part 2 assessed long-term outcomes via the validated Feline Musculoskeletal Pain Index-short form metrology instrument. RESULTS: Mean follow-up time was 66.5 ± 46.7 months (range, 7 to 154 months). Medical management included oral analgesics, activity restriction, and joint supplements. Of the 18 cats, 13 (72%) were always able to bear weight or became weight bearing within a week following initiation of medical management, and 15 (83%) were reportedly clinically normal within 3 months of initiating medical management, with complete resolution of lameness occurring in less than 2 months in 12 of those cats. Long term, 17 of the 18 (94%) owners reported they felt that their cat had a good to excellent outcome with medical management. The mean Feline Musculoskeletal Pain Index-short form score of all cats was 0.29 ± 0.53 (range, 0 to 2.13). CLINICAL RELEVANCE: Based on owner follow-up, conservative, nonsurgical management of CCLD can be an effective and appropriate management strategy for some cats; however, some may be best treated with surgical stabilization.

Phasic flow patterns of right versus left coronary arteries in patients undergoing clinical physiological assessment.

BACKGROUND: Coronary blood flow in humans is known to be predominantly diastolic. Small studies in animals and humans suggest that this is less pronounced or even reversed in the right coronary artery (RCA). AIMS: This study aimed to characterise the phasic patterns of coronary flow in the left versus right coronary arteries of patients undergoing invasive physiological assessment. METHODS: We analysed data from the Iberian-Dutch-English Collaborators (IDEAL) study. A total of 482 simultaneous pressure and flow measurements from 301 patients were included in our analysis. RESULTS: On average, coronary flow was higher in diastole both at rest and during hyperaemia in both the RCA and LCA (mean diastolic-to-systolic velocity ratio [DSVR] was, respectively, 1.85±0.70, 1.76±0.58, 1.53±0.34 and 1.58±0.43 for LCArest, LCAhyp, RCArest and RCAhyp, p<0.001 for between-vessel comparisons). Although the type of RCA dominance affected the DSVR magnitude (RCAdom=1.55±0.35, RCAco-dom=1.40±0.27, RCAnon-dom=1.35; standard deviation not reported as n=3), systolic flow was very rarely predominant (DSVR was greater than or equal to 1.00 in 472/482 cases [97.9%] overall), with equal prevalence in the LCA. Stenosis severity or microvascular dysfunction had a negligible impact on DSVR in both the RCA and LCA (DSVR x hyperaemic stenosis resistance R2 =0.018, p=0.03 and DSVR x coronary flow reserve R2 <0.001, p=0.98). CONCLUSIONS: In patients with coronary artery disease undergoing physiological assessment, diastolic flow predominance is seen in both left and right coronary arteries. Clinical interpretation of coronary physiological data should therefore not differ between the left and the right coronary systems.

Automated Identification of Orthopedic Implants on Radiographs Using Deep Learning.

Accurate identification of metallic orthopedic implant design is important for preoperative planning of revision arthroplasty. Surgical records of implant models are frequently unavailable. The aim of this study was to develop and evaluate a convolutional neural network for identifying orthopedic implant models using radiographs. In this retrospective study, 427 knee and 922 hip unilateral anteroposterior radiographs, including 12 implant models from 650 patients, were collated from an orthopedic center between March 2015 and November 2019 to develop classification networks. A total of 198 images paired with autogenerated image masks were used to develop a U-Net segmentation network to automatically zero-mask around the implants on the radiographs. Classification networks processing original radiographs, and two-channel conjoined original and zero-masked radiographs, were ensembled to provide a consensus prediction. Accuracies of five senior orthopedic specialists assisted by a reference radiographic gallery were compared with network accuracy using McNemar exact test. When evaluated on a balanced unseen dataset of 180 radiographs, the final network achieved a 98.9% accuracy (178 of 180) and 100% top-three accuracy (180 of 180). The network performed superiorly to all five specialists (76.1% [137 of 180] median accuracy and 85.6% [154 of 180] best accuracy; both P < .001), with robustness to scan quality variation and difficult to distinguish implants. A neural network model was developed that outperformed senior orthopedic specialists at identifying implant models on radiographs; real-world application can now be readily realized through training on a broader range of implants and joints, supported by all code and radiographs being made freely available. Supplemental material is available for this article. Keywords: Neural Networks, Skeletal-Appendicular, Knee, Hip, Computer Applications-General (Informatics), Prostheses, Technology Assess-ment, Observer Performance © RSNA, 2021.

Diagnostic accuracy of optical coherence tomography for surgical margin assessment of feline injection-site sarcoma.

The invasive, locally aggressive nature of feline injection-site sarcomas (FISSs) poses a unique challenge for surgeons to obtain complete margins with surgical excision. Optical coherence tomography (OCT), an imaging technology that uses light waves to generate real-time views of tissue architecture, provides an emerging solution to this dilemma by allowing fast, high-resolution scanning of surgical margins. The purpose of this study was to use OCT to assess surgical margins of FISS and to evaluate the diagnostic accuracy of OCT for detecting residual cancer using six evaluators of varying experience. Five FISSs were imaged with OCT to create a training set of OCT images that were compared with histopathology. Next, 25 FISSs were imaged with OCT prior to histopathology. Six evaluators of varying experience participated in a training session on OCT imaging after which each of the evaluators was given a dataset that included OCT images and videos to score on a scale from cancerous to non-cancerous. Diagnostic accuracy statistics were calculated. The overall sensitivity and specificity for classification of OCT images by evaluators were 78.9% and 77.6%, respectively. Correct classification rate of OCT images was associated with experience, while individual sensitivities and specificities had more variation between experience groups. This study demonstrates the ability of evaluators to correctly classify OCT images with overall low levels of experience and training and also illustrates areas where increased training can improve accuracy of evaluators in interpretation of OCT surgical margin images.

Automated Left Ventricular Dimension Assessment Using Artificial Intelligence Developed and Validated by a UK-Wide Collaborative.

BACKGROUND: requires training and validation to standards expected of humans. We developed an online platform and established the Unity Collaborative to build a dataset of expertise from 17 hospitals for training, validation, and standardization of such techniques. METHODS: The training dataset consisted of 2056 individual frames drawn at random from 1265 parasternal long-axis video-loops of patients undergoing clinical echocardiography in 2015 to 2016. Nine experts labeled these images using our online platform. From this, we trained a convolutional neural network to identify keypoints. Subsequently, 13 experts labeled a validation dataset of the end-systolic and end-diastolic frame from 100 new video-loops, twice each. The 26-opinion consensus was used as the reference standard. The primary outcome was precision SD, the SD of the differences between AI measurement and expert consensus. RESULTS: In the validation dataset, the AI's precision SD for left ventricular internal dimension was 3.5 mm. For context, precision SD of individual expert measurements against the expert consensus was 4.4 mm. Intraclass correlation coefficient between AI and expert consensus was 0.926 (95% CI, 0.904-0.944), compared with 0.817 (0.778-0.954) between individual experts and expert consensus. For interventricular septum thickness, precision SD was 1.8 mm for AI (intraclass correlation coefficient, 0.809; 0.729-0.967), versus 2.0 mm for individuals (intraclass correlation coefficient, 0.641; 0.568-0.716). For posterior wall thickness, precision SD was 1.4 mm for AI (intraclass correlation coefficient, 0.535 [95% CI, 0.379-0.661]), versus 2.2 mm for individuals (0.366 [0.288-0.462]). We present all images and annotations. This highlights challenging cases, including poor image quality and tapered ventricles. CONCLUSIONS: Experts at multiple institutions successfully cooperated to build a collaborative AI. This performed as well as individual experts. Future echocardiographic AI research should use a consensus of experts as a reference. Our collaborative welcomes new partners who share our commitment to publish all methods, code, annotations, and results openly.

A Randomized Trial Investigating the Cost-Utility of Patient-Specific Instrumentation in Total Knee Arthroplasty in an Obese Population.

BACKGROUND: Patient-specific instrumentation (PSI) has been introduced in total knee arthroplasty (TKA) with the goal of increased accuracy of component positioning by custom fitting cutting guides to the patient's bony anatomy. A criticism of this technology is the associated cost. The purpose of this randomized controlled trial was to determine the cost-utility of PSI compared with standard of care (SOC) instrumentation for TKA in an obese population. METHODS: Patients with body mass index greater than 30 with osteoarthritis and undergoing primary TKA were randomized to SOC or PSI. Patients completed a health care resource use diary and the EuroQol-5D at three, six, nine, and 12 months and the Western Ontario and McMaster Universities Osteoarthritis Index at three and 12 months postsurgery. We performed cost-utility and cost-effectiveness analyses from public health care payer and societal perspectives. RESULTS: One hundred seventy-three patients were included in the analysis with 86 patients randomized to PSI and 87 to SOC. PSI was dominated (more costly and less effective) by SOC from a health care payer perspective. From a societal perspective, an incremental cost-utility ratio was calculated at $11,230.00 per quality-adjusted life year gained, which is cost-effective at a willingness to pay threshold of $50,000. Net benefit analyses found PSI was not significantly cost-effective at any willingness to pay value from either perspective. CONCLUSION: Our results suggest that widespread adoption of PSI may not be economically attractive or clinically indicated. Future considerations are to compare long-term clinical outcomes and radiographic alignment between the groups.

The economic impact of periprosthetic infection in total knee arthroplasty.

Background: Currently, the gold standard treatment for periprosthetic joint infection (PJI) after total knee arthroplasty (TKA) is 2-stage revision, but few studies have looked at the economic impact of PJI on the health care system. The objective of this study was to obtain an accurate estimate of the institutional cost associated with the management of PJI in TKA and to assess the economic impact of PJI after TKA compared to uncomplicated primary TKA. Methods: We identified consecutive patients in our institutional database who had undergone 2-stage revision TKA for PJI between 2010 and 2014 and matched them on age and body mass index with patients who had undergone uncomplicated primary TKA over the same period. We calculated all costs associated with the 2 procedures and compared mean costs, length of stay, clinical visits and readmission rates between the 2 groups. Results: There were 73 patients (mean age 68.8 [range 48-91] yr) in the revision TKA cohort and 73 patients (mean age 65.9 [range 50-86] yr) in the primary TKA cohort. Two-stage revision surgery was associated with a significantly longer hospital stay (mean 22.7 d v. 3.84 d, p < 0.001), more outpatient clinic visits (mean 8 v. 3, p < 0.001), more readmissions (29 v. 0, p < 0.001) and higher overall cost (mean $35 429.97 v. $6809.94, p < 0.001) than primary TKA. Conclusion: Treatment for PJI after TKA has an enormous economic impact on the health care system. Our data suggest a fivefold increase in expenditure in the management of this complication compared to uncomplicated primary TKA.

Contexte: À l'heure actuelle, le traitement par excellence d'une infection de prothèse articulaire (IPA) survenant après une arthroplastie totale du genou (ATG) est l'arthroplastie de révision en 2 étapes. Toutefois, peu d'études se sont penchées sur les répercussions économiques de l'IPA sur le système de santé. La présente étude visait donc à estimer de façon précise le coût de prise en charge de l'IPA par les établissements, ainsi qu'à évaluer les répercussions économiques de l'IPA après une ATG, comparativement à celles d'une ATG primaire sans complications. Méthodes: Nous avons recensé, dans la base de données de notre établissement, tous les patients consécutifs ayant subi une ATG de révision en 2 étapes pour une IPA entre 2010 et 2014, puis les avons jumelés en fonction de l'âge et de l'indice de masse corporelle avec des patients ayant subi une ATG primaire sans complications durant la même période. Nous avons calculé tous les coûts associés aux 2 interventions, et avons comparé la moyenne des coûts, de la durée d'hospitalisation, des visites cliniques et des réadmissions entre les 2 groupes. Résultats: On comptait 73 patients (âge moyen 68,8 ans [plage 48­91 ans]) dans la cohorte d'ATG de révision, et 73 patients (âge moyen 65,9 ans [plage 50­86 ans]) dans la cohorte d'ATG primaire. L'ATG de révision en 2 étapes, comparativement à l'ATG primaire, a été associée à une durée d'hospitalisation significativement plus longue (moyenne 22,7 j c. 3,84 j; p < 0,001), à un plus grand nombre de visites en clinique externe (moyenne 8 visites c. 3 visites; p < 0,001), à un taux plus élevé de réadmission (29 réadmissions c. 0 réadmission; p < 0,001) et à des coûts globaux plus élevés (moyenne 35 429,97 $ c. 6809,94 $; p < 0,001). Conclusion: Le traitement de l'IPA après une ATG a d'énormes répercussions économiques sur le système de santé. Selon nos données, les dépenses liées à la prise en charge de cette complication pourraient être 5 fois plus élevées que celles liées à une ATG primaire sans complications.

Beta-blocker efficacy across different cardiovascular indications: an umbrella review and meta-analytic assessment.

BACKGROUND: Beta-blockers are widely used for many cardiovascular conditions; however, their efficacy in contemporary clinical practice remains uncertain. METHODS: We performed a prospectively designed, umbrella review of meta-analyses of randomised controlled trials (RCTs) investigating the evidence of beta-blockers in the contemporary management of coronary artery disease (CAD), heart failure (HF), patients undergoing surgery or hypertension (registration: PROSPERO CRD42016038375). We searched MEDLINE, EMBASE and the Cochrane Library from inception until December 2018. Outcomes were analysed as beta-blockers versus control for all-cause mortality, myocardial infarction (MI), incident HF or stroke. Two independent investigators abstracted the data, assessed the quality of the evidence and rated the certainty of evidence. RESULTS: We identified 98 meta-analyses, including 284 unique RCTs and 1,617,523 patient-years of follow-up. In CAD, 12 meta-analyses (93 RCTs, 103,481 patients) showed that beta-blockers reduced mortality in analyses before routine reperfusion, but there was a lack of benefit in contemporary studies where ≥ 50% of patients received thrombolytics or intervention. Beta-blockers reduced incident MI at the expense of increased HF. In HF with reduced ejection fraction, 34 meta-analyses (66 RCTs, 35,383 patients) demonstrated a reduction in mortality and HF hospitalisation with beta-blockers in sinus rhythm, but not in atrial fibrillation. In patients undergoing surgery, 23 meta-analyses (89 RCTs, 19,211 patients) showed no effect of beta-blockers on mortality for cardiac surgery, but increased mortality in non-cardiac surgery. In non-cardiac surgery, beta-blockers reduced MI after surgery but increased the risk of stroke. In hypertension, 27 meta-analyses (36 RCTs, 260,549 patients) identified no benefit versus placebo, but beta-blockers were inferior to other agents for preventing mortality and stroke. CONCLUSIONS: Beta-blockers substantially reduce mortality in HF patients in sinus rhythm, but for other conditions, clinicians need to weigh up both benefit and potential risk.