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Background: The electrophysiological mechanism connecting mitral valve prolapse (MVP), premature ventricular complexes and life-threatening ventricular arrhythmia is unknown. A common hypothesis is that stretch activated channels (SACs) play a significant role. SACs can trigger depolarizations or shorten repolarization times in response to myocardial stretch. Through these mechanisms, pathological traction of the papillary muscle (PM), as has been observed in patients with MVP, may induce irregular electrical activity and result in reentrant arrhythmia. Methods: Based on a patient with MVP and mitral annulus disjunction, we modeled the effect of excessive PM traction in a detailed medical image-derived ventricular model by activating SACs in the PM insertion region. By systematically varying the onset of SAC activation following sinus pacing, we identified vulnerability windows for reentry with 1 ms resolution. We explored how reentry was affected by the SAC reversal potential ( E SAC ) and the size of the region with simulated stretch (SAC region). Finally, the effect of global or focal fibrosis, modeled as reduction in tissue conductivity or mesh splitting (fibrotic microstructure), was investigated. Results: In models with healthy tissue or fibrosis modeled solely as CV slowing, we observed two vulnerable periods of reentry: For E SAC of -10 and -30 mV, SAC activated during the T-wave could cause depolarization of the SAC region which lead to reentry. For E SAC of -40 and -70 mV, SAC activated during the QRS complex could result in early repolarization of the SAC region and subsequent reentry. In models with fibrotic microstructure in the SAC region, we observed micro-reentries and a larger variability in which times of SAC activation triggered reentry. In these models, 86% of reentries were triggered during the QRS complex or T-wave. We only observed reentry for sufficiently large SAC regions ( > = 8 mm radius in models with healthy tissue). Conclusion: Stretch of the PM insertion region following sinus activation may initiate ventricular reentry in patients with MVP, with or without fibrosis. Depending on the SAC reversal potential and timing of stretch, reentry may be triggered by ectopy due to SAC-induced depolarizations or by early repolarization within the SAC region.

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Fragmentation/loss of the structural protein elastin represents the precipitating event translating to aortic expansion and subsequent aneurysm formation. The present study tested the hypothesis that greater protein expression of tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) and neointimal growth secondary to a reduction of medial elastin content represent sex-dependent events limiting aortic vessel expansion in females. TIMP-1 protein levels were higher in the ascending aorta of female versus male patients diagnosed with a bicuspid aortic valve (BAV). The latter paradigm was recapitulated in the aorta of adult male and female rats complemented by greater TIMP-2 expression in females. CaCl2 (0.5 M) treatment of the infrarenal aorta of adult male and female rats increased the in situ vessel diameter and expansion was significantly smaller in females despite a comparable reduction of medial elastin content. The preferential appearance of a neointimal region of the CaCl2-treated infrarenal aorta of female rats may explain in part the smaller in situ expansion and neointimal growth correlated positively with the % change of the in situ diameter. Neointimal formation was secondary to a significant increase in the density of medial/neointimal vascular smooth muscle cells (VSMCs) that re-entered the G2-M phase whereas VSMC cell cycle re-entry was attenuated in the CaCl2-treated infrarenal aorta of male rats. Thus, greater TIMP-1 expression in the aorta of female BAV patients may prevent excessive elastin fragmentation and preferential neointimal growth following CaCl2-treatment of the infrarenal aorta of female rats represents a sex-dependent biological event limiting vessel expansion secondary to a significant loss of the structural protein.

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In seeking to improve upon CTO percutaneous coronary intervention (PCI) success rates and minimize risk, CTO modification procedures (investment procedures) have been developed and utilized with increasing frequency. Two key techniques have emerged: subintimal tracking and re-entry (STAR) and subintimal plaque modification (SPM). Both require a staged approach with an index procedure for plaque modification and a second procedure weeks later for stenting. Both approaches require entry and wiring with a polymer jacketed wire in the extra plaque space (EPS), yet unlike SPM which exclusively requires angioplasty of the EPS throughout the CTO segment, STAR also involves re-entry into the true lumen distal to the CTO before angioplasty. STAR and SPM in many ways represent a paradigm shift in our approach to CTO PCI from a 1-step to 2-step approach in complex cases. In this review, we discuss the technical aspects of the procedures, as well as controversies and ongoing trials pointing to the future of these techniques. We also highlight non-device-based and intravascular ultrasound-based approaches to antegrade dissection and re-entry, which add to the CTO operator's toolkit for challenging cases.

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Background: Aortic dissection is the most common acute aortic syndrome, and renal artery is the most common involved artery. The size and location of the re-entry tear directly affect the blood flow enhancement of the false lumen branch artery after surgery. In this study, the morphology and hemodynamics of the re-entry tear were comprehensively analyzed, and the location and size of the re-entry tear were quantitatively evaluated to calculate the re-entry tear index (RTI). This study aimed to assess the predictive capability of a comprehensive quantitative RTI for improvement in renal perfusion following thoracic endovascular aortic repair (TEVAR) in cases of acute and subacute Stanford type B aortic dissection with renal artery involvement. Methods: In this prospective cohort study, 137 patients diagnosed with acute or subacute type B aortic dissection with concomitant renal artery involvement who underwent TEVAR at Anzhen Hospital in Beijing from October 2017 to November 2021 were enrolled. Renal blood flow was estimated quantitatively with ultrasound. Based on the ultrasound findings of renal artery flow, the patients were classified into two groups: group A [postoperative volume flow (VolFlow) reduced compared to preoperative VolFlow] and group B (postoperative VolFlow increased compared to preoperative VolFlow). All re-entry tears present in the aortic trunk according to reconstructed computed tomography angiography (CTA) obtained preoperatively were included in the analysis. The general information of patients, whether the involved renal artery arose partially or wholly from the false lumen, the proximal diameter and length of the covered stent, the diameter of primary entry tear, the RTI, etc. were analyzed. Univariate and multivariate logistic regression analyses were executed to assess the risk factors associated with increased renal arterial blood flow subsequent to TEVAR. Additionally, receiver operating characteristic (ROC) curve analysis was used to ascertain the optimal cutoff value and predictive efficacy of the RTI. Results: A total of 137 patients, comprising of 32 with acute and 105 with subacute type B aortic dissection accompanied by renal artery involvement, underwent TEVAR. Among these patients, 44 (32.1%) were assigned to group A and 93 (67.9%) to group B. Renal blood flow exhibited an increase in 67.9% of the patients after TEVAR. The results of multivariate analysis indicated that the RTI is an independent risk factor for postoperative renal perfusion improvement [odds ratio =17.66; 95% confidence interval (CI): 2.13-78.55; P=0.020]. The optimal cutoff value for RTI, determined to be 0.033, demonstrated the ability to identify renal perfusion improvement in patients without hypertension with a sensitivity of 53.7% and a specificity of 68.9%. In patients with concomitant hypertension, RTI exhibited a sensitivity of 96.6% and a specificity of 60.0%, with an area under the ROC curve (AUC) of 0.792 (95% CI: 0.643-0.941; P=0.021) for identifying renal perfusion improvement. Conclusions: RTI demonstrated a favorable predictive value for improving renal malperfusion following TEVAR in cases of aortic dissection with renal artery involvement.

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OBJECTIVE: Concerns exist about clinical and operative skill decay in surgery residents when they dedicate time away from clinical training to pursue research. However, it remains undetermined how to best prevent these negative impacts. Our study evaluated the perspectives of surgical research residents on interventions to improve their reentry into clinical training. DESIGN, SETTING, AND PARTICIPANTS: An anonymous web-based survey was distributed between 5/01/2023 and 6/01/2023 to 102 current and former (within the previous 3 years) general surgery research residents from 4 academic medical centers in Boston, MA. RESULTS: Survey response rate was 35.3% (36/102 residents). About 22 of 36 residents (61.1%) felt that their clinical aptitude decreased during the research years, whereas 33 of 36 (91.7%) reported reduced surgical skills. When reflecting on their re-entry to residency, former research residents reported feeling anxious and less confident (3.84/5 on a 1-5 Likert scale) as well as being below the expected level of clinical performance (3.42/5). Most of them (12 of 17; 70.6%) reported that it took up to 6 months, whereas 5 of them (29.4%) up to 12 months to feel at the expected level. When compared to nonmoonlighting residents, those who moonlighted often and operated during moonlighting, denied a decrease in clinical and surgical skills, and reported less anxiety, higher confidence, and a quicker return to the expected level of performance. Interventions proposed for improving their clinical re-entry included individualized development plans for 3 months before returning to clinical training, established curriculum for clinical work throughout the research years, clinical preceptorships throughout the research years, and simulation curriculum throughout the research years. CONCLUSIONS: General surgery residents feel that their clinical and surgical skills decreased during the research years, leading to anxiety and lack of confidence when returning to residency. Therefore, comprehensive interventions are needed to improve the reentry of the research residents into clinical training.

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Sternal reentry for repair of aortic pseudoaneurysms poses a unique technical challenge to prevent exsanguination. Initiation of peripheral cardiopulmonary bypass and deep hypothermic circulatory arrest prior to reentry are the cornerstones of a successful surgical approach. Adjunctive bilateral antegrade cerebral perfusion increases safe arrest time and reduces neurologic morbidity. Herein, we describe our safe reentry technique for aortic pseudoaneurysm repair in two patients.

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The goal was to study the implementation of rapid BINAX COVID-19 testing at criminal justice reentry sites, focusing on framework-guided implementation outcomes. We implemented rapid COVID-19 testing at nine reentry sites in four states (Massachusetts, New Hampshire, Rhode Island, and New York) and collected test results to measure the (1) adoptability and (2) implementability of COVID-19 testing at reentry sites. We collected data on the acceptability, appropriateness, and feasibility of the implementation of COVID-19 testing using an anonymous employee Qualtrics survey. Testing was available to symptomatic and exposed residents and employees. COVID-19 testing results were collected from October 2021 to March 2022. Guided by the Expert Recommendations in Implementing Change (ERIC) framework, we chose nine implementation strategies to address barriers during the implementation process. Acceptability, appropriateness, and feasibility outcomes were captured from employees using validated measures. A total of 302 BINAX COVID-19 tests were used and 26 positive cases were identified. Forty-seven percent of employees participated in the survey. More than half of respondents either agreed or completely agreed with statements about the acceptability, appropriateness, or feasibility of COVID-19 testing. Funding and attention toward COVID-19 testing at reentry sites should be provided to help prevent the spread of COVID-19 in these sites.

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Myocardial edema is a common symptom of pathological processes in the heart, causing aggravation of cardiovascular diseases and leading to irreversible myocardial remodeling. Patient-based studies show that myocardial edema is associated with arrhythmias. Currently, there are no studies that have examined how edema may influence changes in calcium dynamics in the functional syncytium. We performed optical mapping of calcium dynamics on a monolayer of neonatal rat cardiomyocytes with Fluo-4. The osmolality of the solutions was adjusted using the NaCl content. The initial Tyrode solution contained 140 mM NaCl (1T) and the hypoosmotic solutions contained 105 (0.75T) and 70 mM NaCl (0.5T). This study demonstrated a sharp decrease in the calcium wave propagation speed with a decrease in the solution osmolality. The successive decrease in osmolality also showed a transition from a normal wavefront to spiral wave and multiple wavelets of excitation with wave break. Our study demonstrated that, in a cellular model, hypoosmolality and, as a consequence, myocardial edema, could potentially lead to fatal ventricular arrhythmias, which to our knowledge has not been studied before. At 0.75T spiral waves appeared, whereas multiple wavelets of excitation occurred in 0.5T, which had not been recorded previously in a two-dimensional monolayer under conditions of cell edema without changes in the pacing protocol.

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Captan dislodgeable foliar residues (DFRs) were determined by following the applications of this fungicide in an apple orchard. The study comprised an investigation of the variability of captan DFR values and 14 days of DFR monitoring to assess kinetic modeling. A method combining solid-phase microextraction (SPME) gas chromatography and high-resolution mass spectrometry (GC-QTOF-MS) was developed for the quantification of captan residues from DFR aqueous extracts. The results evidenced that (1) sampling parameters such as the position of the tree in a row and the height of foliar significantly influenced captan DFR levels (247-1450 ng·cm-2), highlighting the need to implement a comprehensive sampling strategy; (2) the DFR captan dissipation kinetic model best matched with a biphasic one, with half-lives of DFRcaptan of 3.4 and 12.8 days, respectively, for the initial rapid phase 1 decline (day 0-5) and the slower phase 2 decline phase (day 6-14). Furthermore, through DFR measurements, the potential dermal exposure (PDE) of workers was assessed using transfer coefficients (TCs) from the literature. Compared to the acceptable operator exposure levels (AOELs), the results showed that the re-entry interval for captan may not sufficiently protect workers whose arms, hands, and legs are not covered.

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BACKGROUND: Ten to fifteen percent of chronic total occlusion (CTO) percutaneous coronary interventions (PCIs) are unsuccessful in contemporary practice. Subintimal tracking and re-entry (STAR) (one form of "investment procedure") with staged reattempt and stenting may further increase the ultimate success and safety of CTO as a bailout strategy. The optimal timing for staged stenting after STAR is unknown. METHODS AND RESULTS: We designed a six-center, prospective randomized trial with a planned enrollment of 150 patients where STAR is utilized in case of impending failure. The primary aim is to evaluate the optimal timing of the staged PCI after STAR by randomizing the timing to earlier (5-7 weeks) versus later (12-14 weeks) staged PCI. The primary endpoint of the study is the technical success rate of the staged procedure. The secondary endpoints include: (1) the rate of thrombolysis in myocardial infarction 3 flow at the start of staged intervention, (2) rate of partial technical and procedural success of the staged procedure, (3) rate of in-hospital and 12-month major cardiac and cerebrovascular adverse events, and (4) change in patient-reported quality at 30 days, 6 months, and 12 months assessed by Seattle Angina Questionnaire. CONCLUSION: This study will ascertain the optimal timing of staged stenting after bail-out STAR approach in contemporary CTO PCI (ClinicalTrials.gov NCT05089864).

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Introduction: Fibrotic scar in the heart is known to act as a substrate for arrhythmias. Regions of fibrotic scar are associated with slowed or blocked conduction of the action potential, but the detailed mechanisms of arrhythmia formation are not well characterised and this can limit the effective diagnosis and treatment of scar in patients. The aim of this computational study was to evaluate different representations of fibrotic scar in models of 2D 10 × 10 cm ventricular tissue, where the region of scar was defined by sampling a Gaussian random field with an adjustable length scale of between 1.25 and 10.0 mm. Methods: Cellular electrophysiology was represented by the Ten Tusscher 2006 model for human ventricular cells. Fibrotic scar was represented as a spatially varying diffusion, with different models of the boundary between normal and fibrotic tissue. Dispersion of activation time and action potential duration (APD) dispersion was assessed in each sample by pacing at an S1 cycle length of 400 ms followed by a premature S2 beat with a coupling interval of 323 ms. Vulnerability to reentry was assessed with an aggressive pacing protocol. In all models, simulated fibrosis acted to delay activation, to increase the dispersion of APD, and to generate re-entry. Results: A higher incidence of re-entry was observed in models with simulated fibrotic scar at shorter length scale, but the type of model used to represent fibrotic scar had a much bigger influence on the incidence of reentry. Discussion: This study shows that in computational models of fibrotic scar the effects that lead to either block or propagation of the action potential are strongly influenced by the way that fibrotic scar is represented in the model, and so the results of computational studies involving fibrotic scar should be interpreted carefully.

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Accumulation of advanced glycation end-products (AGEs) in the brain contributes significantly to cognitive impairment in patients with diabetes by disrupting the post-mitotic state of neuronal cells, thereby triggering ectopic cell cycle re-entry (CCR) and subsequent neuronal apoptosis. Cinnamaldehyde (CINA), a potential mitigator of cognitive impairment due to its blood glucose-lowering properties, warrants exploration for its role in counteracting diabetes-related neurological damage. In this study, we examined the neuroprotective effect of CINA on AGE-damaged SH-SY5Y human neuroblastoma cells differentiated in vitro. We investigated the impact of CINA on AGE-induced neuronal CCR and apoptosis, finding that it substantially suppressed aberrant DNA replication, precluded cells from entering the mitotic preparatory phase, and diminished apoptosis. Additionally, CINA inhibited the expression of eIF4E without altering S6K1 phosphorylation. These findings indicate that CINA safeguards neuronal cells from AGE-related damage by preventing abnormal CCR, preserving the post-mitotic state of neuronal cells, and reducing AGE-induced apoptosis, potentially through the inhibition of eIF4E-controlled cell proliferation. Our results highlight the prospective utility of CINA in managing diabetic neuropathy.

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OBJECTIVE: To examine the challenges faced by Asian working mothers with a focus on re-entry to the workplace. In addition, we highlight potential supports that retain women in the workforce. DESIGN: A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations and registered with PROSPERO database (CRD42022341130). METHODS: Three independent reviewers were involved in the study selection to screen the search results sequentially by title, abstract, and full text using predefined inclusion and exclusion criteria. The methodological quality of each article was assessed via the Critical Appraisal Skills Programme (CASP) tool. RESULTS: We analysed a total of 36 studies conducted across different regions: 30 from the East and 6 from Southeast Asia. Among these studies, 20 were quantitative in nature, 15 were qualitative, and one intervention. The 36 studies cover five themes: 1) policies, 2) external support sources, 3) external pressure, 4) breastfeeding and 5) health status. Within each theme the same factor can have a positive or negative impact on the mother depending on her having a pro-career or pro-family mindset. Companies can take various initiatives to support working mothers, such as providing facilities for expressing breast milk at the workplace, educating staff to promote breastfeeding and accommodate childcare needs, and extending maternity leaves. However, there is a lack of literature that directly addresses the barriers and concrete support available to working mothers in Asia, beyond the scope of breastfeeding. CONCLUSIONS: Our findings underscore several obstacles that can impede a woman's seamless return to work. Pro-family and pro-career mothers have differing needs that cannot be addressed at the same time. There is a lack of comprehensive understanding regarding effective strategies or interventions that can support a positive reintegration into the workforce.

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A 70-year-old man with hypertensive heart disease underwent catheter ablation of persistent atrial fibrillation. After completing the pulmonary vein isolation, atrial burst pacing induced an annular atrial tachycardia (AT). Overdrive pacing exhibited constant fusion, indicating a macroreentrant mechanism of the AT. However, the CARTO3 activation map created using the Octaray catheter (both Biosense Webster, Irvine, CA) exhibited a centrifugal spread with the earliest activation site at the 4 o'clock position of the tricuspid annulus. In contrast, the Ripple map revealed a clear reentrant circuit with its isthmus located at the 4-6 o'clock position of the tricuspid annulus. The local electrograms in these areas recorded systolic and diastolic potentials simultaneously, and the misannotation of the large far-field potentials caused this discrepant result. Handling low-amplitude complex fractionated electrograms remains a challenge in creating a precise activation mapping. The Ripple map, especially when combined with the Octaray catheter, was effective in dynamically visualizing all these electrograms and accurately delineating the reentrant circuit.

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BACKGROUND: The period of community re-entry following residential substance use treatment is associated with elevated risk for return to substance use. Although continuity of care is best practice, many individuals do not engage in follow-up treatment, struggle to engage in follow-up treatment, or continue to use substances while participating in follow-up treatment. There is a need to both characterize treatment engagement during community re-entry following residential substance use treatment as well as understand how treatment impacts substance use during this high-risk period. METHOD: This observational study used retrospective self-report to examine treatment engagement and substance use among individuals who had exited residential substance use treatment. Participants completed a Timeline Follow-back interview reporting substance use and treatment engagement in the 30 days following residential treatment. RESULTS: Most participants (83.1 %) reported engaging in substance use treatment following discharge. The most common treatments were Alcoholics Anonymous/Narcotics Anonymous (61.1 %), medication for addiction treatment (40 %), and outpatient therapy (29.2 %). Participants were less likely to use substances on a day in which they engaged in outpatient therapy (OR = 0.32, 95 % CI [0.12, 0.90], p = 0.030) and more likely on days they engaged in medication treatment (OR = 21.49, 95 % CI [1.46, 316.74], p = 0.025). CONCLUSION: Findings characterize engagement in substance use treatment in the month following residential treatment. Treatment engagement was common during community re-entry; however, only outpatient therapy was found to reduce substance use during this high-risk period. Findings may inform intervention efforts during the high-risk period of community re-entry.

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BACKGROUND: Epicardial unipolar mapping has not been thoroughly investigated in Brugada syndrome (BrS). OBJECTIVES: This study aims to examine the characteristics of epicardial unipolar potentials in BrS and investigate the differences from overt cardiomyopathy. METHODS: Epicardial mapping was performed in 8 patients with BrS and 6 patients with cardiomyopathy. We investigated the J-wave amplitudes using unipolar recordings at delayed potential (DP) sites via bipolar recordings. The repolarization time (RT) at and around the DP recording sites was measured, and maximum dispersion of the RT divided by the distance was defined as the RT dispersion index. RESULTS: Epicardial mapping at baseline revealed significantly higher J-wave amplitude with bipolar DP in patients with BrS than in patients with cardiomyopathy. J-wave amplitude ≥0.42 mV had 99.1% sensitivity and 100% specificity for diagnosing BrS. The RT dispersion index was significantly higher in patients with BrS than in patients with cardiomyopathy at baseline. In all patients with BrS, coved-type unipolar electrograms without negative T waves (short RT) appeared close to coved-type electrograms with negative T waves (long RT) at the DP recording sites after pilsicainide administration. Thus, a steep RT dispersion was observed in this region, and ventricular arrhythmias emerged from this shorter RT area in all 3 patients with BrS in whom ventricular arrhythmias were induced. CONCLUSIONS: Bipolar DP-related prominent unipolar J waves and steep repolarization gradients may be more specific for characterizing BrS than for overt cardiomyopathy. Ventricular arrhythmias in BrS are associated with a steep repolarization gradient, indicating phase 2 re-entry as a possible cause.

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Traumatic brain injury (TBI) is a serious public health concern and overrepresented among justice-involved populations. An emerging area of research focuses on the complex, interrelated and unmet health and social needs of justice-involved women and youth with TBI. Evidence of these needs continues to grow, yet the health and justice systems continue to underperform in supporting the health and social care of justice-involved women and youth. This commentary is a call to action to begin to redress these gaps. We first provide an overview of the needs of women and youth with TBI that affect their transition from custody to community, including those related to victimization, trauma, mental health, substance use, and homelessness. We then highlight the current gaps in knowledge and practice with respect to interventions for women and youth with TBI at transition from custody. The available evidence for the impact of interventions on people with head injury who are justice-involved is sparse, especially studies of interventions focused on women and youth. We conclude with a call for implementation science studies to support translation from research to practice, emphasizing that researchers, practitioners, policy makers, and women and youth at transition should collaborate to develop, implement, and evaluate accommodations and interventions for TBI. To have meaningful, positive impacts on the systems that serve these women and youth, interdisciplinary service delivery approaches should aim to prevent, raise awareness, identify, and provide timely support and services for the varied needs of women and youth with TBI in transition.