Comparing the compensatory reserve metric obtained from invasive arterial measurements and photoplethysmographic volume-clamp during simulated hemorrhage.

PURPOSE: The compensatory reserve metric (CRM) is a novel tool to predict cardiovascular decompensation during hemorrhage. The CRM is traditionally computed using waveforms obtained from photoplethysmographic volume-clamp (PPGVC), yet invasive arterial pressures may be uniquely available. We aimed to examine the level of agreement of CRM values computed from invasive arterial-derived waveforms and values computed from PPGVC-derived waveforms. METHODS: Sixty-nine participants underwent graded lower body negative pressure to simulate hemorrhage. Waveform measurements from a brachial arterial catheter and PPGVC finger-cuff were collected. A PPGVC brachial waveform was reconstructed from the PPGVC finger waveform. Thereafter, CRM values were computed using a deep one-dimensional convolutional neural network for each of the following source waveforms; (1) invasive arterial, (2) PPGVC brachial, and (3) PPGVC finger. Bland-Altman analyses were used to determine the level of agreement between invasive arterial CRM values and PPGVC CRM values, with results presented as the Mean Bias [95% Limits of Agreement]. RESULTS: The mean bias between invasive arterial- and PPGVC brachial CRM values at rest, an applied pressure of -45mmHg, and at tolerance was 6% [-17%, 29%], 1% [-28%, 30%], and 0% [-25%, 25%], respectively. Additionally, the mean bias between invasive arterial- and PPGVC finger CRM values at rest, applied pressure of -45mmHg, and tolerance was 2% [-22%, 26%], 8% [-19%, 35%], and 5% [-15%, 25%], respectively. CONCLUSION: There is generally good agreement between CRM values obtained from invasive arterial waveforms and values obtained from PPGVC waveforms. Invasive arterial waveforms may serve as an alternative for computation of the CRM.

Phage K exposure generates phage-neutralizing activity in a rabbit model-humoral receptiveness may impact efficacy of phage therapy.

Phage therapy has not been established in the clinical routine, in part due to uncertainties concerning efficacy and immunogenicity. Here, three rabbits were immunized against staphylococcal phage K to assess viral potency in the presence of immunized serum. Three rabbits received weekly intramuscular injections of ~1010±1 pfu/mL phage K. Phage K-specific IgG formation was measured by an enzyme-linked immunosorbent assay (ELISA); phage inactivation was assessed by calculating K-rates. Using transmission electron microscopy (TEM) and immunogold labeling, antibody binding to phage K was visualized. This was numerically assessed by objective imaging analysis comparing the relative distances of each gold particle to the nearest phage head and tail structure. Immunization led to a strong IgG response, plateauing 7 days after the last phage injection. There was no significant correlation between K-rate and antibody titer over time. TEM showed IgG binding to the head structure of phage K. Image analysis showed a significant reduction in relative distances between antibodies and phage head structures when comparing samples from day 0 and day 28 (P < 0.0001). These results suggest that while individual serum analysis for antibodies against therapeutic phage bears consideration prior to and with prolonged therapy, during phage application, the formation of specific antibodies against phage may only partially explain decreased phage potency in the presence of immunized serum. Instead, other factors may contribute to an individual's "humoral receptiveness" to phage therapy. Future investigations should be directed toward the identification of the humoral factors that have the most significant predictive value on phage potency in vivo.

MR Imaging Features of Critical Spinal Demyelinating Lesions Associated with Progressive Motor Impairment.

BACKGROUND AND PURPOSE: Progressive MS is typically heralded by a myelopathic pattern of asymmetric progressive motor weakness. Focal individual "critical" demyelinating spinal cord lesions anatomically associated with progressive motor impairment may be a compelling explanation for this clinical presentation as described in progressive solitary sclerosis (single CNS demyelinating lesion), progressive demyelination with highly restricted MR imaging lesion burden (2-5 total CNS demyelinating lesions; progressive paucisclerotic MS), and progressive, exclusively unilateral hemi- or monoparetic MS (>5 CNS demyelinating progressive unilateral hemi- or monoparetic MS [PUHMS] lesions). Critical demyelinating lesions appear strikingly similar across these cohorts, and we describe their specific spinal cord MR imaging characteristics. MATERIALS AND METHODS: We performed a retrospective, observational MR imaging study comparing spinal cord critical demyelinating lesions anatomically associated with progressive motor impairment with any additional "noncritical" (not anatomically associated with progressive motor impairment) spinal cord demyelinating lesions. All spinal cord MR images (302 cervical and 91 thoracic) were reviewed by an experienced neuroradiologist with final radiologic assessment on the most recent MR imaging. Anatomic association with clinical progressive motor impairment was confirmed independently by MS subspecialists. RESULTS: Ninety-one individuals (PUHMS, 37 [41%], progressive paucisclerosis 35 [38%], progressive solitary sclerosis 19 [21%]) with 91 critical and 98 noncritical spinal cord MR imaging demyelinating lesions were evaluated. MR imaging characteristics that favored critical spinal cord demyelinating lesions over noncritical lesions included moderate-to-severe, focal, lesion-associated spinal cord atrophy: 41/91 (45%) versus 0/98 (0%) (OR, 161.91; 9.43 to >999.9); lateral column axial location (OR, 10.43; 3.88-28.07); central region (OR, 3.23; 1.78-5.88); ventral column (OR, 2.98; 1.55-5.72); and larger lesion size of the axial width (OR, 2.01;1.49-2.72), transverse axial size (OR, 1.66; 1.36-2.01), or lesion area (OR, 1.14; 1.08-1.2). Multiple regression analysis revealed focal atrophy and lateral axial location as having the strongest association with critical demyelinating lesions. CONCLUSIONS: Focal, lesion-associated atrophy, lateral column axial location, and larger lesion size are spinal cord MR imaging characteristics of critical demyelinating lesions. The presence of critical demyelinating lesions should be sought as these features may be associated with the development of progressive motor impairment in MS.

Physiologic validation of the compensatory reserve metric obtained from pulse oximetry: A step towards advanced medical monitoring on the battlefield.

BACKGROUND: The Compensatory Reserve Metric (CRM) provides a time sensitive indicator of hemodynamic decompensation. However, its in-field utility is limited due to the size and cost-intensive nature of standard vital sign monitors or photoplethysmographic volume-clamp (PPGVC) devices used to measure arterial waveforms. In this regard, photoplethysmographic measurements obtained from pulse oximetry (PPGPO) may serve as a useful, portable alternative. This study aimed to validate CRM values obtained using PPGPO. METHODS: Forty-nine healthy adults (25 females) underwent a graded lower body negative pressure (LBNP) protocol to simulate hemorrhage. Arterial waveforms were sampled using PPGPO and PPGVC. The CRM was calculated using a one-dimensional convolutional neural network. Cardiac output and stroke volume were measured using PPGVC. A brachial artery catheter was used to measure intraarterial pressure. A 3-lead ECG was used to measure heart rate. Fixed-effect linear mixed models with repeated measures were used to examine the association between CRM values and physiologic variables. Log-rank analyses were used to examine differences in shock determination during LBNP between monitored hemodynamic parameters. RESULTS: The median LBNP stage reached was 70 mmHg (Range: 45-100 mmHg). Relative to baseline, at tolerance there was a 47±12% reduction in stroke volume, 64±27% increase in heart rate, and 21±7% reduction in systolic blood pressure (P<0.001 for all). CRM values obtained with both PPGPO and PPGVC were associated with changes in heart rate (P<0.001), stroke volume (P<0.001), and pulse pressure (P<0.001). Furthermore, they provided an earlier detection of hemodynamic shock relative to the traditional metrics of shock index (P<0.001 for both), systolic blood pressure (P<0.001 for both), and heart rate (P=0.001 for both). CONCLUSION: The CRM obtained from PPGPO provides a valid, time-sensitized prediction of hemodynamic decompensation, opening the door to provide military medical personnel noninvasive in-field advanced capability for early detection of hemorrhage and imminent onset of shock. LEVEL OF EVIDENCE: Diagnostic Tests or Criteria, Level IV.

γ-Glutamyl Transferase and Long-Term Survival in the SYNTAXES Trial: Is It Just the Liver?

BACKGROUND: Recently, machine learning algorithms have identified preprocedural γ-glutamyl transferase (GGT) as a significant predictor of long-term mortality after coronary revascularization in the SYNTAX (Synergy Between PCI [Percutaneous Coronary Intervention] With Taxus and Cardiac Surgery) trial. The aim of the present study is to investigate the impact of preprocedural GGT on 10-year all-cause mortality in patients with complex coronary artery disease after revascularization. METHODS AND RESULTS: The SYNTAX trial was a randomized trial comparing PCI with coronary artery bypass grafting in 1800 patients with complex coronary artery disease. The present report is a post hoc subanalysis of the SYNTAXES (Synergy Between PCI With Taxus and Cardiac Surgery Extended Survival) trial, an investigator-driven extended 10-year follow-up of the SYNTAX trial. The association between preprocedural GGT and 10-year all-cause mortality was investigated. The mean values of GGT for men and women were 43.5 (SD, 48.5) and 36.4 (SD, 46.1) U/L, respectively. In multivariable Cox regression models adjusted by traditional risk factors, GGT was an independent predictor for all-cause death at 10-year follow-up, and each SD increase in log-GGT was associated with a 1.24-fold risk of all cause death at 10-year follow-up (95% CI, 1.10-1.40). According to previously reported sex-related GGT thresholds, patients with higher GGT level had a 1.74-fold risk of all-cause death at 10-year follow-up (95% CI, 1.32-2.29) compared with patients with lower GGT level. CONCLUSIONS: Preprocedural GGT is an independent predictor of 10-year mortality after coronary revascularization in patients with complex coronary artery disease. In patients with elevated GGT, strong secondary prevention may be required after revascularization and must be studied prospectively. REGISTRATION: URL: https://clinicaltrials.gov/study/NCT03417050.

Automated Web-based Software for CT Quality Control Testing of Low-contrast Detectability using Model Observers.

The Channelized Hotelling observer (CHO) is well correlated with human observer performance in many CT detection/classification tasks but has not been widely adopted in routine CT quality control and performance evaluation, mainly because of the lack of an easily available, efficient, and validated software tool. We developed a highly automated solution - CT image quality evaluation and Protocol Optimization (CTPro), a web-based software platform that includes CHO and other traditional image quality assessment tools such as modulation transfer function and noise power spectrum. This tool can allow easy access to the CHO for both the research and clinical community and enable efficient, accurate image quality evaluation without the need of installing additional software. Its application was demonstrated by comparing the low-contrast detectability on a clinical photon-counting-detector (PCD)-CT with a traditional energy-integrating-detector (EID)-CT, which showed UHR-T3D had 6.2% higher d' than EID-CT with IR (p = 0.047) and 4.1% lower d' without IR (p = 0.122).

Disproportionately High Aortic Valve Calcium Scores in Atrial Fibrillation: Implications for Transcatheter Aortic Valve Replacement.

AIMS: Doppler mean gradient (MG) can underestimate aortic stenosis (AS) severity in patients with atrial fibrillation (AF) compared to patients in sinus rhythm (SR), potentially delaying intervention in AF. This study compared outcomes in patients with AF and SR following transcatheter aortic valve replacement (TAVR) and investigated delay in TAVR based on computed tomography aortic valve calcium score (AVCS). METHODS AND RESULTS: Patients who underwent TAVR from 2013 to 2017 for native valve severe AS were identified from an institutional database. Baseline characteristics and overall survival were compared between those in SR and AF. There were 820 patients (mean age 81 years; 41.6% female) included. AF was present in 356 patients. Patients in AF were older (82.2 vs. 80.5, p = 0.003), had lower MG compared to SR patients (42.0 vs. 44.9, p = 0.002) with similar indexed aortic valve area (0.4 vs. 0.4, p = 0.17). Median AVCS was higher in AF (males: AF 2850.0 vs. SR 2561.0, p = 0.044; females: AF 1942.0 vs. SR 1610.5, p = 0.025). Projected AVCS assuming same age of diagnosis was similar between AF and SR. Median survival post-TAVR was worse in AF compared to SR (3.2 vs 5.4 years, log rank p < 0.001). AF, lower MG, higher RVSP, dialysis, diabetes, and significant TR were associated with higher mortality (p < 0.05 for all). CONCLUSION: Older age and higher AVCS in patients with AF compared to SR suggests that AS was both underestimated and more advanced at TAVR referral.

Evaluating and improving the usability of a mHealth platform to assess postoperative dental pain.

Objectives: The use of interactive mobile health (mHealth) applications to monitor patient-reported postoperative pain outcomes is an emerging area in dentistry that requires further exploration. This study aimed to evaluate and improve the usability of an existing mHealth application. Materials and methods: The usability of the application was assessed iteratively using a 3-phase approach, including a rapid cognitive walkthrough (Phase I), lab-based usability testing (Phase II), and in situ pilot testing (Phase III). The study team conducted Phase I, while providers and patients participated in Phase II and III. Results: The rapid cognitive walkthrough identified 23 potential issues that could negatively impact user experience, with the majority classified as system issues. The lab-based usability testing yielded 141 usability issues.; 43% encountered by patients and 57% by dentists. Usability problems encountered during pilot testing included undelivered messages due to mobile phone carrier and service-related issues, errors in patients' phone number data entry, and problems in provider training. Discussion: Through collaborative and iterative work with the vendor, usability issues were addressed before launching a trial to assess its efficacy. Conclusion: The usability of the mHealth application for postoperative dental pain was remarkably improved by the iterative analysis and interdisciplinary collaboration.

Health Care Worker Education for Palliative Care in Africa: Narrative Review.

The demand for palliative care for terminally ill patients is rising globally. This review examines the potential of health worker education to enhance palliative care in Africa. A search of PubMed yielded 32 relevant articles published in English from 2013 to 2023 focused on African countries with WHO-categorized palliative care development and health care worker training. The findings underscore the pivotal role of health care worker education in elevating palliative care standards. Targeted initiatives equip health care workers with vital skills in pain management, symptom control, and communication. The integration of palliative care into public health systems is important for the sustainability of end-of-life care for terminally ill patients in Africa and around the world.

Comparative Costs to Medicare and Medicare Beneficiaries of Alternative AF Stroke Risk Reduction Strategies.

Background: As healthcare costs are increasingly being shifted from payers to patients, it is important to understand the economic consequences of therapeutic strategies to both payers and patients. Objective: To determine the relative costs to Medicare and Medicare beneficiaries (patients) of warfarin, non-vitamin K oral anticoagulants (NOACs), and left atrial appendage closure (LAAC) for stroke risk reduction in nonvalvular atrial fibrillation. Methods: An economic model was developed to assess costs at 5 and 10 years. For warfarin and NOACs, inputs were derived from published meta-analyses; for LAAC with the Watchman device, inputs were derived from pooled 5-year PROTECT AF and PREVAIL trial results. The model captured therapy costs vs clinical event costs, including procedural complications and follow-up clinical outcomes. Costs were based on 2023 Medicare reimbursement and copayment rates. Results: At 10 years, overall LAAC costs ($48,337) were lower than those of NOACs ($81,198) and warfarin ($52,359). Overall LAAC costs were lower than those of NOACs by year 5 and warfarin by year 9. At 5 years, patient LAAC costs were lowest at $4,764, compared to $7,146 and $6,453 for NOACs and warfarin, respectively. LAAC patient costs were lower than those of NOACs by year 3 and warfarin by year 4. Clinical events comprised 96% of overall warfarin costs vs 48% for LAAC and 40% for NOACs. Conclusion: LAAC yielded the lowest overall and patient costs. Warfarin costs were largely driven by clinical events, which may represent an unplanned financial burden for patients. These considerations should be incorporated into shared decision-making discussions about stroke prophylaxis strategies.

Patient and dentist perspectives on collecting patient reported outcomes after painful dental procedures in the National Dental PBRN.

BACKGROUND: Dental Patient Reported Outcomes (PROs) relate to a dental patient's subjective experience of their oral health. How practitioners and patients value PROs influences their successful use in practice. METHODS: Semi-structured interviews were conducted with 22 practitioners and 32 patients who provided feedback on using a mobile health (mHealth) platform to collect the pain experience after dental procedures. A themes analysis was conducted to identify implementation barriers and facilitators. RESULTS: Five themes were uncovered: (1) Sense of Better Care. (2) Tailored Follow-up based on the dental procedure and patient's pain experience. (3) Effective Messaging and Alerts. (4) Usable Digital Platform. (5) Routine mHealth Integration. CONCLUSION: Frequent automated and preferably tailored follow-up messages using an mHealth platform provided a positive care experience for patients, while providers felt it saved them time and effort. Patients thought that the mHealth questionnaires were well-developed and of appropriate length. The mHealth platform itself was perceived as user-friendly by users, and most would like to continue using it. PRACTICAL IMPLICATIONS: Patients are prepared to use mobile phones to report their pain experience after dental procedures. Practitioners will be able to close the post-operative communication gap with their patients, with little interruption of their workflow.

Coronary spasm and vasomotor dysfunction as a cause of MINOCA.

Increasing evidence has shown that coronary spasm and vasomotor dysfunction may be the underlying cause in more than half of myocardial infarctions with non-obstructive coronary arteries (MINOCA) as well as an important cause of chronic chest pain in the outpatient setting. We review the contemporary understanding of coronary spasm and related vasomotor dysfunction of the coronary arteries, the pathophysiology and prognosis, and current and emerging approaches to diagnosis and evidence-based treatment.

Impact of left ventricular ejection fraction on 10-year mortality in the SYNTAX trial.

BACKGROUNDS: The impact of reduced left ventricular ejection fraction (LVEF) on very long-term prognosis following percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) has been debated. The aim of this study was to investigate the impact of LVEF at baseline on 10-year mortality in the SYNTAX trial. METHODS: Patients (n = 1800) were categorized into three sub-groups: reduced (rEF ≤ 40 %), mildly reduced (mrEF 41-49 %), and preserved LVEF (pEF ≥ 50 %). The SYNTAX score 2020 (SS-2020) was applied in patients with LVEF<50 % and ≥ 50 %. RESULTS: Ten-year mortalities were 44.0 %, 31.8 %, and 22.6 % (P < 0.001) in patients with rEF (n = 168), mrEF (n = 179), and pEF (n = 1453). Although no significant differences were observed, the mortality with PCI was higher than with CABG in patients with rEF (52.9 % vs 39.6 %, P = 0.054) and mrEF (36.0 % vs. 28.6 %, P = 0.273), and comparable in pEF (23.9 % vs. 22.2 %, P = 0.275). Calibration and discrimination of the SS-2020 in patients with LVEF<50 % were poor, whilst they were reasonable in those with LVEF≥50 %. The proportion of patients eligible for PCI who had a predicted equipoise in mortality with CABG was estimated to be 57.5 % in patients with LVEF≥50 %. CABG was safer than PCI in 62.2 % of patients with LVEF<50 %. CONCLUSIONS: Reduced LVEF was associated with an increased risk of 10-year mortality in patients revascularized either surgically or percutaneously. Compared to PCI, CABG was safe revascularization in patients with LVEF≤40 %. In patients with LVEF≥50 % individualized 10-year all-cause mortality predicted by SS-2020 was helpful in decision-making whilst the predictivity in patients with LVEF<50 % was poor.

Targeted Training Reduces Search Errors but Not Classification Errors for Hepatic Metastasis Detection at Contrast-Enhanced CT.

RATIONALE AND OBJECTIVES: Methods are needed to improve the detection of hepatic metastases. Errors occur in both lesion detection (search) and decisions of benign versus malignant (classification). Our purpose was to evaluate a training program to reduce search errors and classification errors in the detection of hepatic metastases in contrast-enhanced abdominal computed tomography (CT). MATERIALS AND METHODS: After Institutional Review Board approval, we conducted a single-group prospective pretest-posttest study. Pretest and posttest were identical and consisted of interpreting 40 contrast-enhanced abdominal CT exams containing 91 liver metastases under eye tracking. Between pretest and posttest, readers completed search training with eye-tracker feedback and coaching to increase interpretation time, use liver windows, and use coronal reformations. They also completed classification training with part-task practice, rating lesions as benign or malignant. The primary outcome was metastases missed due to search errors (<2 seconds gaze under eye tracker) and classification errors (>2 seconds). Jackknife free-response receiver operator characteristic (JAFROC) analysis was also conducted. RESULTS: A total of 31 radiologist readers (8 abdominal subspecialists, 8 nonabdominal subspecialists, 15 senior residents/fellows) participated. Search errors were reduced (pretest 11%, posttest 8%, difference 3% [95% confidence interval, 0.3%-5.1%], P = .01), but there was no difference in classification errors (difference 0%, P = .97) or in JAFROC figure of merit (difference -0.01, P = .36). In subgroup analysis, abdominal subspecialists demonstrated no evidence of change. CONCLUSION: Targeted training reduced search errors but not classification errors for the detection of hepatic metastases at contrast-enhanced abdominal CT. Improvements were not seen in all subgroups.

The medical device development ecosystem: Current regulatory state and challenges for future development: A review.

BACKGROUND/PURPOSE: There has been increasing emphasis on the development of new technology to mitigate unmet clinical needs in cardiovascular disease. This emphasis results in part from recognition that many devices, although being initially developed in the United States, were studied, and then eventually approved abroad before being returned to the U.S. for clinical application. The FDA (Food and Drug Administration) guidance document on Early Feasibility Studies (EFS) and then the 21st Century Cures Act from 2013 to 2016 focused on these issues. MATERIALS/METHODS: There are multiple components of medical device translational pathways to be considered in continuing to reach the goal of providing early access to safe and effective products to the U.S. POPULATION: This review article documents the various stages from early idea innovation to device design and iteration to clinical testing and then potential approval and application in the wide clinical practice of cardiovascular health care. RESULTS: The CDRH (Centers for Devices and Radiological Health) has focused on key components including EFS, Breakthrough Devices Program, Total Product Life Cycle, the Unique Device Identification Program, the establishment of a Digital Health Center of Excellence, and leveraging Collaborative Communities. Each of these initiatives focuses on improving the Medical Device Development Ecosystem. CONCLUSIONS: Major changes in device translational research have improved the device research climate in the United States. Goals remain including increased training and education for constituencies aspiring to work in the field of device development and regulation as part of a continuous health care learning system.

Comparative genomics sheds light on transcription factor-mediated regulation in the extreme acidophilic Acidithiobacillia representatives.

Extreme acidophiles thrive in acidic environments, confront a multitude of challenges, and demonstrate remarkable adaptability in their metabolism to cope with the ever-changing environmental fluctuations, which encompass variations in temperature, pH levels, and the availability of electron acceptors and donors. The survival and proliferation of members within the Acidithiobacillia class rely on the deployment of transcriptional regulatory systems linked to essential physiological traits. The study of these transcriptional regulatory systems provides valuable insights into critical processes, such as energy metabolism and nutrient assimilation, and how they integrate into major genetic-metabolic circuits. In this study, we examined the transcriptional regulatory repertoires and potential interactions of forty-three Acidithiobacillia complete and draft genomes, encompassing nine species. To investigate the function and diversity of Transcription Factors (TFs) and their DNA Binding Sites (DBSs), we conducted a genome-wide comparative analysis, which allowed us to identify these regulatory elements in representatives of Acidithiobacillia. We classified TFs into gene families and compared their occurrence among all representatives, revealing conservation patterns across the class. The results identified conserved regulators for several pathways, including iron and sulfur oxidation, the main pathways for energy acquisition, providing new evidence for viable regulatory interactions and branch-specific conservation in Acidithiobacillia. The identification of TFs and DBSs not only corroborates existing experimental information for selected species, but also introduces novel candidates for experimental validation. Moreover, these promising candidates have the potential for further extension to new representatives within the class.

Towards a Lightweight Classifier to Detect Hypovolemic Shock.

Predicting the ability of an individual to compensate for blood loss during hemorrhage and detect the likely onset of hypovolemic shock is necessary to permit early clinical intervention. Towards this end, the compensatory reserve metric (CRM) has been demonstrated to directly correlate with an individual's ability to maintain compensatory mechanisms during loss of blood volume from onset (one-hundred percent health) to exsanguination (zero percent health). This effort describes a lightweight, three-class predictor (good, fair, poor) of an individual's compensatory reserve using a linear support-vector machine (SVM) classifier. A moving mean filter of the predictions demonstrates a feasible model for implementation of real-time hypovolemia monitoring on a wearable device, requiring only 408 bytes to store the models' coefficients and minimal processor cycles to complete the computations.

Identification of Sleep Patterns via Clustering of Hypnodensities.

Sleep patterns vary widely between individuals. We explore methods for identifying populations exhibiting similar sleep patterns in an automated fashion using polysomnography data. Our novel approach applies unsupervised machine learning algorithms to hypnodensities graphs generated by a pre-trained neural network. In a population of 100 subjects we identify two stable clusters whose characteristics we visualize graphically and through estimates of total sleep time. We also find that the hypnodensity representation of the sleep stages produces more robust clustering results than the same methods applied to traditional hypnograms.

Cerebral emboli detection and autonomous neuromonitoring using robotic transcranial Doppler with artificial intelligence for transcatheter aortic valve replacement with and without embolic protection devices: a pilot study.

BACKGROUND: Periprocedural ischemic stroke remains a serious complication in patients undergoing transcatheter aortic valve replacement (TAVR). We used a novel robotic transcranial Doppler (TCD) system equipped with artificial intelligence (AI) for real-time continuous intraoperative neuromonitoring during TAVR to establish the safety and potential validity of this tool in detecting cerebral emboli, report the quantity and distribution of high intensity transient signals (HITS) with and without cerebral protection, and correlate HITS occurrence with various procedural steps. METHODS: Consecutive patients undergoing TAVR procedures during which the robotic system was used between October 2021 and May 2022 were prospectively enrolled in this pilot study. The robotic TCD system included autonomous adjustment of the TCD probes and AI-assisted post-processing of HITS and other cerebral flow parameters. Basic demographics and procedural details were recorded. Continuous variables were analyzed by a two-sample Mann-Whitney t-test and categorical variables by a χ2 or Fisher test. RESULTS: Thirty-one patients were prospectively enrolled (mean age 79.9±7.6 years; 16 men (51.6%)). Mean aortic valve stenotic area was 0.7 cm2 and mean aortic-ventricular gradient was 43 mmHg (IQR 31.5-50 mmHg). Cerebral protection was used in 16 cases (51.6%). Significantly fewer emboli were observed in the protection group than in the non-protection group (mean 470.38 vs 693.33; p=0.01). Emboli counts during valve positioning and implantation were significantly different in the protection and non-protection groups (mean 249.92 and 387.5, respectively; p=0.01). One (4%) transient ischemic attack occurred post-procedurally in the non-protection group. CONCLUSION: We describe a novel real-time intraoperative neuromonitoring tool used in patients undergoing TAVR. Significantly fewer HITS were detected with protection. Valve positioning-implantation was the most significant stage for intraprocedural HITS.

DAPT Is Comparable to OAC Following LAAC With WATCHMAN FLX: A National Registry Analysis.

BACKGROUND: Left atrial appendage occlusion (LAAO) is an approved alternative for stroke prevention in atrial fibrillation for patients with an "appropriate rationale" to avoid long-term oral anticoagulation (OAC). Many patients undergoing LAAO are at high risk of bleeding. OBJECTIVES: This study sought to investigate whether dual antiplatelet therapy (DAPT) is a safe alternative to OAC (direct oral anticoagulation [DOAC] or warfarin) with aspirin after LAAO. METHODS: Using National Cardiovascular Data Registry LAAO registry data, patients undergoing Watchman FLX (Boston Scientific) implantation (August 5, 2020-September 30, 2021) were included in 1:1 propensity-matched analyses comparing discharge medication regimens (DAPT, DOAC/aspirin, or warfarin/aspirin). A composite endpoint (death, stroke, major bleeding, and systemic embolism), its components, and device-related thrombus between discharge and 45 days were evaluated. RESULTS: In 49,968 patients implanted with the Watchman FLX during the study period, the mean age was 77 years, and 40% were women. Postimplant DOAC/aspirin was prescribed in 24,497 patients, warfarin/aspirin in 3,913, and DAPT in 4,155. DAPT patients had more comorbid conditions than patients receiving OAC/aspirin. After propensity score matching, the 45-day composite endpoint rates were similar among the groups (DAPT = 3.44% vs DOAC/aspirin: 4.06%; P = 0.13 and DAPT = 3.23% vs warfarin/aspirin: 3.08%; P = 0.75). Death, stroke, and device-related thrombus were also similar; major bleeding was slightly increased in DOAC/aspirin patients (DAPT = 2.48% vs DOAC/aspirin = 3.25%; P = 0.04 and DAPT = 2.25% vs warfarin/aspirin = 2.22%; P = 0.93). CONCLUSIONS: In a large registry, DAPT had a similar safety profile compared with current Food and Drug Administration-approved postimplant drug regimens of OAC with aspirin following LAAO with the Watchman FLX. Shared decision making for nonpharmacologic stroke prevention should include a discussion of postprocedure medical therapy options.