Mild aortic insufficiency following transcatheter aortic valve replacement: A systematic review and meta-analysis.

BACKGROUND: Post-procedural aortic insufficiency (AI) continues to be prevalent following transcatheter aortic valve replacement (TAVR). While several studies have assessed the outcomes of moderate-severe AI following TAVR, the incidence, predictors, and outcomes of mild AI remain unclear. METHODS: A systematic literature review was performed to identify studies reporting on mild AI following TAVR. The primary outcome was pooled incidence of post-TAVR mild AI. Secondary outcomes included pooled incidence of mild AI at 30 days and long term. The pooled incidence of midterm mortality in patients with post-TAVR mild AI was also evaluated. The random effect generalized linear mixed-effects model with logit-transformed proportions and Hartung-Knapp adjustment was used to calculate pooled incidence rates. Meta-regression was performed to identify predictors of mild AI. RESULTS: The pooled analysis included 19,241 patients undergoing TAVR across 50 studies. The mean age of patients ranged from 73 to 85 years, and female patients ranged from 20.0% to 83.3%. The overall pooled incidence of post-TAVR mild AI was 56.1% (95% confidence interval [CI] 0.31-0.64). The pooled incidence of mild AI at 30 days was 33.7% (95% CI 0.12-0.37). At mean follow-up of 1.15 years, the pooled incidence of mild AI was 37.0% (95% CI 0.16-0.45). The overall pooled incidence of Midterm mortality (mean follow-up 1.22 years) in patients with mild AI was 14.8% (95% CI 0.10-0.25). At meta-regression, none of the explored variables correlated with a difference in mild AI incidence. CONCLUSIONS: In published studies to date, 50% of patients undergoing TAVR develop mild AI postoperatively. In 37% of patients, this persists in long term. Though the incidence of AI is likely improving with newer generation TAVR valves, the prevalence and outcomes of mild AI should be closely monitored as TAVR volume and indications expand to younger patients with long life expectancy. The long-term outcomes of mild AI remain unclear. Further dedicated studies on post-TAVR mild AI are needed.

Neighborhood Socioeconomic Status Independently Predicts Outcomes After Mitral Valve Surgery.

BACKGROUND: Socioeconomic status has increasingly recognized influence on outcomes after cardiac surgery. However, singular metrics fail to fully capture the socioeconomic context within which patients live, which vary greatly between neighborhoods. We sought to explore the impact of neighborhood-level socioeconomic status on patients undergoing mitral valve surgery in the United States. METHODS: Adults undergoing first-time, isolated mitral valve surgery were queried from The Society of Thoracic Surgeons Adult Cardiac Surgery Database between 2012 and 2018. Socioeconomic status was quantified using the Area Deprivation Index, a weighted composite including average housing prices, household incomes, education, and employment levels. The associations between regional deprivation, access to mitral surgery, valve repair rates, and outcomes were evaluated using logistic regression. RESULTS: Among 137,100 patients included, patients with socioeconomic deprivation had fewer elective presentations, more comorbidity burden, and more urgent/emergent surgery. Patients from less disadvantaged areas received operations from higher volume surgeons and had higher repair rates (highest vs lowest quintile: 72% vs 51%, P < .001, more minimally-invasive approach (33% vs 20%, P < .001), lower composite complication rate (42% vs 50%, P < .001), and lower 30-day mortality (1.8% vs 3.9%, P < .001). After hierarchical multivariable adjustment, the Area Deprivation Index significantly predicted 30-day mortality and repair rate (P < .001). CONCLUSIONS: In a risk-adjusted national analysis of mitral surgery, patients from more deprived areas were less likely to undergo mitral repair and more likely to have complications. Further work at targeting neighborhood-level disparity is important to improving mitral surgical outcomes in the United States.

Pot-bellied Vietnamese pig with visceral mast cell tumors and mastocytemia.

An approximately 12-year-old female Vietnamese Pot-Bellied Pig was presented to the Mississippi State College of Veterinary Medicine Food Animal Service for anorexia of 2 days duration. On physical examination, the patient appeared depressed and lethargic with significantly pale mucus membranes, open mouth breathing, and nostril flaring. On abdominal palpation, the abdomen was tense and uncomfortable. A complete blood count (CBC) and chemistry profile were performed. The CBC revealed significant anemia and mild leukocytosis characterized by mild neutrophilia with a left shift. Mast cells were rarely observed. Hematocrit = 8.1% (RI 22-50), RBC = 1.25 × 106 /µL (RI 3.6-7.8), WBC = 19.85 × 103 /µL (RI 5.2-17.9), Neutrophils = 15.08 × 103 /µL (RI 0-11.4), and Bands = 0.993 × 103 /µL (RI 0-0.019). The chemistry profile was unremarkable with a mildly elevated BUN and slightly decreased total protein and albumin (BUN = 39 mg/dL [RI 4.2-15.1], total protein = 6.2 g/dL [RI 6.6-8.9], and albumin = 2.5 g/dL [RI 3.6-5.0]). An abdominal ultrasound revealed numerous hypoechoic nodules diffusely scattered throughout the hepatic parenchyma. An FNA of one of the hepatic nodules was performed. A mild suppurative component and numerous variably granulated mast cells were observed. A presumptive cytologic diagnosis of mast cell tumor was made. Histopathology was performed, confirming the cytologic interpretation.

CSF from a puppy with a cerebral vascular hamartoma.

A 9-week-old puppy with refractory seizures and a dome-shaped head presented to the Mississippi State College of Veterinary Medicine Specialty Center for suspected hydrocephalus. Computerized tomography (CT) findings included transtentorial herniation and an intra-axial mass with dystrophic mineralization. Cerebrospinal fluid analysis revealed an increased nucleated cell count of 1100/µl (RI < 5/µl), erythrocyte count of 2.2 × 106 /µl, and markedly increased microprotein of 1939 mg/dl (RI < 30 mg/dl). On cytologic examination of the CSF, numerous erythrophagocytic, and hemosiderin-laden macrophages were observed, which indicated chronic active hemorrhage. Many neutrophils, macrophages, and lymphocytes that contained numerous intracytoplasmic, pleomorphic, bright yellow crystals were observed. Considering the ongoing hemorrhage, the crystals were presumed to be hematoidin. A biopsy with histopathology was performed on the intra-axial mass, and the results were consistent with a vascular hamartoma. We speculate that the formation of these crystals was related to the ongoing hemorrhage associated with the vascular hamartoma. Identification of these crystals may be useful to aid in the identification of chronic hemorrhage associated with vascular malformations or lesions within the central nervous system.

Disrupting drive-by download networks on Twitter.

This paper tests disruption strategies in Twitter networks containing malicious URLs used in drive-by download attacks. Cybercriminals use popular events that attract a large number of Twitter users to infect and propagate malware by using trending hashtags and creating misleading tweets to lure users to malicious webpages. Due to Twitter's 280 character restriction and automatic shortening of URLs, it is particularly susceptible to the propagation of malware involved in drive-by download attacks. Considering the number of online users and the network formed by retweeting a tweet, a cybercriminal can infect millions of users in a short period. Policymakers and researchers have struggled to develop an efficient network disruption strategy to stop malware propagation effectively. We define an efficient strategy as one that considers network topology and dependency on network resilience, where resilience is the ability of the network to continue to disseminate information even when users are removed from it. One of the challenges faced while curbing malware propagation on online social platforms is understanding the cybercriminal network spreading the malware. Combining computational modelling and social network analysis, we identify the most effective strategy for disrupting networks of malicious URLs. Our results emphasise the importance of specific network disruption parameters such as network and emotion features, which have proved to be more effective in disrupting malicious networks compared to random strategies. In conclusion, disruption strategies force cybercriminal networks to become more vulnerable by strategically removing malicious users, which causes successful network disruption to become a long-term effort.

Coronary Endarterectomy: Analysis of The Society of Thoracic Surgeons Adult Cardiac Surgery Database.

BACKGROUND: Coronary endarterectomy (CE) is an uncommon and often unplanned technique used to approach difficult targets during coronary artery bypass grafting (CABG). We evaluated the outcomes of CABG with CE (CE-CABG) using The Society of Thoracic Surgeons Adult Cardiac Surgery Database. METHODS: All isolated, first-time, elective or urgent CABG cases from July 2011 to September 2019 in the Adult Cardiac Surgery Database were retrospectively reviewed. Because of a higher risk profile in the patients undergoing CE-CABG, we performed propensity score matching. Primary outcomes included operative mortality and postoperative myocardial infarction. For patients ≥65 years, long-term mortality and rehospitalization were evaluated using linked data from Centers for Medicare and Medicaid Services. RESULTS: Of the total 1 111 792 patients included, 32 164 (2.9%) had CE-CABG and 1 079 628 (97.1%) underwent CABG alone. The majority of CE-CABG involved a single-vessel endarterectomy (86.9%; n = 27 945); the left anterior descending was most common (40.9%; n = 13 161). Compared with propensity score-matched CABG, CE-CABG had increased operative mortality (3.2% vs 1.7%; P < .0001; odds ratio, 1.81; 95% CI, 1.63-2.01) and postoperative myocardial infarction (6.8% vs 3.9%; P < .0001; odds ratio, 1.80; 95% CI, 1.68-1.93). CE-CABG had higher risk of mortality in the first year and rehospitalization for myocardial infarction in the first 3 years but was comparable to CABG alone thereafter. Subgroup analysis showed no difference between CE-CABG of the left anterior descending compared with CE-CABG of other coronary arteries. CONCLUSIONS: This analysis demonstrates that CE-CABG has acceptable long-term outcomes and serves as a benchmark for what can be expected when this rare procedure is used.

Neighborhood socioeconomic status is associated with differences in operative management and long-term survival after coronary artery bypass grafting.

OBJECTIVE: We sought to characterize differences in operative management and surgical outcomes after coronary artery bypass grafting associated with the socioeconomic context in which a patient lives. METHODS: We used a validated index of 17 variables derived from the US Census Bureau to assign socioeconomic status at the block group level to patients who underwent isolated coronary artery bypass grafting at a single institution over a 16-year period. Operative mortality, stroke, renal failure, prolonged ventilation, sternal wound infection, reoperation, composite morbidity or mortality, long-term survival, and use of arterial conduits were the outcomes assessed. RESULTS: This study was composed of 6751 patients. Lower socioeconomic status was significantly associated with increased rates of stroke, renal failure, prolonged ventilation, and composite morbidity or mortality in a multivariable analysis. Low socioeconomic status was significantly associated with poorer long-term adjusted survival (hazard ratio, 1.26; 95% confidence interval, 1.03-1.55). Finally, lower socioeconomic status was significantly associated with decreased use of more than 1 arterial conduits in a multivariable analysis. CONCLUSIONS: The socioeconomic context in which a patient lives is significantly associated with short- and long-term outcomes after coronary artery bypass grafting. There may also be variation in operative management, demonstrated by decreased use of arterial conduits. Lower rates of arterial revascularization among socioeconomically disadvantaged patients who undergo coronary artery revascularization may provide a target for intervention.

Thirty-Year Trends in Graft Survival After Heart Transplant: Modeled Analyses of a Transplant Registry.

BACKGROUND: Heart failure is an epidemic in the United States, and transplantation remains the most definitive therapy. We describe multidecade trends in posttransplant graft survival, adjusted for concurrent changes in the population, over the 30 years antecedent to the most recent heart allocation policy change. METHODS: Scientific Registry of Transplant Recipients data were used to identify all primary adult heart recipients from 1989 to 2017. We described temporal changes in population characteristics (recipient and donor demographics and comorbidities, pretransplant interventions, clinical transplant measures, and providers). The primary outcome was graft survival, defined as freedom from all-cause death and graft failure, within 6 months posttransplant. Modified Poisson logistic regression estimated relative changes in risk of outcomes compared with 1989, with and without adjustment for changing population characteristics. We identified risk factors, quantified by associated risk ratios. RESULTS: Among 56,488 primary adult heart recipients, we observed 5529 (9.8%) all-cause deaths and 1933 (3.4%) graft failure events within 6 months posttransplant. Prevalence of known recipient risk factors increased over time. Unadjusted modeling demonstrated a significant 30-year improvement in graft survival, averaging 2.6% per year (95% confidence interval, 2.4-2.9; P for trend < .001). After adjusting for population changes the 30-year trend remained significant and graft survival improved on average 3.0% per year (95% confidence interval, 2.6-3.3). Regression modeling identified multiple predictors of graft survival. Modeling 2 additional outcomes of 6-month mortality and 6-month graft failure produced similar results. CONCLUSIONS: Short-term graft survival after heart transplantation has improved significantly leading up to the 2018 heart allocation policy change, despite concurrent increase in prevalence of higher risk population characteristics.

Clinical and Echocardiographic Results of Aortic Valve Replacement in the Failing Ventricle: Do Aortic Stenosis and Aortic Regurgitation Differ?

BACKGROUND: We hypothesized that long-term clinical and echocardiographic recovery of the impaired ventricle from pressure (aortic stenosis [AS]) and volume (aortic regurgitation [AR]) overload would be different after aortic valve replacement (AVR). METHODS: We compared the results of AVR in patients with a preoperative ejection fraction (EF) of 0.35 or less due to AS, AR, or mixed disease. We constructed a mixed-effects model of EF and left ventricular (LV) end-diastolic diameter (LVEDD) to understand ventricular recovery over the short- (in-hospital), intermediate- (3-6 months), and longer- (>24 months) terms. We sought to identify factors associated with clinical and echocardiographic recovery using multivariable analysis. RESULTS: Between July 2011 and 2017, 136 patients with a preoperative EF of 0.35 or less and severe AS (n = 83), severe AR (n = 18), or mixed AS and AR (n = 35) underwent AVR. There were 2 (1.5%) early deaths in the AS group. Survival at 1, 2, and 5 years did not differ between groups. Baseline EF did not differ between the groups but improved with markedly different trajectory and time course in the AS, AR, and mixed groups over time. LVEDD regressed in all patient cohorts, following a different pattern for AS and AR. Baseline EF and LVEDD predicted the long-term fate of the LV but did not determine survival. We identify factors associated with long-term survival. CONCLUSIONS: The pattern of LV recovery appears to be early in AS and delayed in AR. Baseline clinical factors, rather than echocardiographic status of the LV, appear to determine late survival.

Effect of washing units of canine red blood cells on storage lesions.

BACKGROUND: In humans, washing stored blood products before transfusion reduces storage lesions and incidence of transfusion reactions, but the effectiveness of washing canine blood is unknown. OBJECTIVES: The objective was to determine if manually washing units of stored blood would reduce storage lesions without adversely affecting erythrocytes. We hypothesized that washing stored units would reduce concentrations of storage lesions and cause minimal erythrocyte damage. ANIMALS: Eight healthy research dogs. METHODS: Repeated measure cohort study. Units of whole blood were stored for 28 days and washed 3 times with 0.9% NaCl. Blood samples were collected before and after storage, after each wash, and after being held at a simulated transfusion temperature. Variables measured included CBC variables, blood gas analysis, erythrocyte morphology, mean corpuscular fragility (MCF), and eicosanoid concentrations. A Friedman's test was used to evaluate changes in variables (P < .05 was considered significant). RESULTS: After the first wash, compared to values after storage, there was a significant decrease in potassium (4.3 mmol/L [4.0-4.7] to 1.2 mmol/L [1-1.6]; P < .0001, median [range]), lactate (1.45 mmol/L [1.07-1.79] to 0.69 mmol/L [0.39-0.93]; P = .002), and partial pressure carbon dioxide (102 mm Hg [80.2-119.2] to 33.7 mm Hg [24.5-44.5]; P < .0001), and increase in MCV (69.3 fL [65.7-72.3] to 74 fL [69.6-79.5]; P = .0003), and MCF (0.444 fL [0.279-0.527] to 0.491 fL [0.43-0.616]; P = .0006). CONCLUSIONS AND CLINICAL IMPORTANCE: A single wash of stored whole blood significantly reduces most extracellular storage lesions, and additional washing might cause hemolysis.

The learning curve of robotic coronary arterial bypass surgery: A report from the STS database.

BACKGROUND: There is limited data to inform minimum case requirements for training in robotically assisted coronary artery bypass grafting (RA-CABG). Current recommendations rely on nonclinical endpoints and expert opinion. OBJECTIVES: To determine the minimum number of RA-CABG procedures required to achieve stable clinical outcomes. METHODS: We included isolated RA-CABG in the Society of Thoracic Surgeons (STS) registry performed between 2014 and 2019 by surgeons without prior RA-CABG experience. Outcomes were approach conversion, reoperation, major morbidity or mortality, and procedural success. Case sequence number was used as a continuous variable in logistic regression with restricted cubic splines with fixed effects. Outcomes were compared between operations performed earlier versus later in case sequences using unadjusted and adjusted metrics. RESULTS: There were 1195 cases performed by 114 surgeons. A visual inflection point occurs by a surgeon's 10th procedure for approach conversion, major morbidity or mortality, and overall procedural success after which outcomes stabilize. There was a significant decrease in the rate of approach conversion (7.7% and 2.5%), reoperation (18.9% and 10.8%), and major morbidity or mortality (21.7% and 12.9%), as well as an increase in the rate of procedural success (72.9% and 85.3%) with increasing experience between groups. In a multivariable logistic regression model, case sequences of >10 were an independent predictor of decreased approach conversion (odds ratio [OR]: 0.27; 95% confidence interval [CI]: 0.09-0.84) and increased rate procedural success (OR: 1.96; 95% CI: 1.00-3.84). CONCLUSIONS: The learning curve for RA-CABG is initially steep, but stable clinical outcomes are achieved after the 10th procedure.

COVID-19 and cardiothoracic surgery: Effects on training and workforce utilization in a global pandemic.

BACKGROUND: The COVID-19 pandemic has disrupted all aspects of healthcare, including cardiothoracic surgery (CTS). We sought to determine the pandemic's impact on CTS trainees' educational experiences. METHODS: A survey was developed and distributed to members of the Thoracic Surgery Residents Association and other international CTS trainees. Trainees were asked to evaluate their cumulative experiences and share their overall perceptions of how CTS training had been impacted during the earliest months of the COVID-19 pandemic (i.e., since March 01, 2020). Surveys were distributed and responses were recorded June 25-August 05, 2020. In total, 748 surveys were distributed and 166 responses were received (overall response rate 22.2%). Of these, 126 of 166 responses (75.9%) met inclusion criteria for final analysis. RESULTS: Final responses analyzed included 45 of 126 (35.7%) United States (US) and 81 of 126 (64.3%) international trainees, including 101 of 126 (80.2%) senior and 25 of 126 (19.8%) junior trainees. Most respondents (76/126, 43.2%) lost over 1 week in the hospital due to the pandemic. Juniors (12/25, 48.0%) were more likely than seniors (20/101, 19.8%) to be reassigned to COVID-19-specific units (p < .01). Half of trainees (63/126) reported their case volumes were reduced by over 50%. US trainees (42/45, 93.3%) were more likely than international trainees (58/81, 71.6%) to report reduced operative case volumes (p < .01). Most trainees (104/126, 83%) believed their overall clinical acumen was not adversely impacted by the pandemic. CONCLUSIONS: CTS trainees in the United States and abroad have been significantly impacted by the COVID-19 pandemic, with time lost in the hospital, decreased operative experiences, less time on CTS services, and frequent reassignment to COVID-19-specific care settings.

Wisdom From Past Presidents of The Society of Thoracic Surgeons.

The Society of Thoracic Surgeons is a highly impactful professional organization in cardiothoracic surgery and an important network of mentors for trainees. Annually, presidents of The Society of Thoracic Surgeons deliver an address encapsulating their professional experiences, lessons learned, and future vision for the field. We sought to summarize these lessons into salient points for trainees. Transcriptions from 1964 to 2018 were reviewed by residents and expounded into categories of importance for readers. Six overarching themes were identified: (1) leadership, (2) education, (3) clinical excellence and innovation, (4) humanism and professionalism, (5) diversity and inclusion, and (6) the future of cardiothoracic surgery.

Characteristics and Attitudes of Aspiring Cardiothoracic Surgeons: A Survey Study.

BACKGROUND: Although recruiting highly qualified, diverse applicants into cardiothoracic surgery remains a national priority, their characteristics remain unknown. This study aims to describe current and future applicants in cardiothoracic surgery. METHODS: Aspiring cardiothoracic surgeons (students interested in matriculating in a North American training program) were voluntarily enrolled in the study through Twitter and email outreach. A 33-question survey evaluated their backgrounds, research experiences, attitudes, and interests within cardiothoracic surgery. Standard descriptive statistics were used. RESULTS: There were 111 participants, 40 of whom were female (36.0%) and 27 of whom identified as an underrepresented minority (24.3%). Of the total, 63 belonged to an institution with a cardiothoracic surgery training program (56.8%). A total of 91 students envisioned having a mostly operative career (82.0%) and 75 envisioned pursuing educational roles (67.6%). The most popular surgical specialties were heart transplantation (50.5%) and aortic surgery (47.8%). Participants selected having a high-intensity operative environment (81.2%) and an innovative academic environment (58.8%) as the most attractive qualities. Perceived lack of work-life balance (46%) and toxic training or work environment (28%) were the greatest deterrents. Finances during the application process were perceived as a potential barrier by 41 students (36.9%). Approximately 75% of students (83 of 111) had faculty as mentors; 46.8% (56 of 111) thought that cardiothoracic surgery faculty were approachable but had limited time for mentorship. CONCLUSIONS: This survey study characterized a nationally selected pool of aspiring cardiothoracic surgeons using social media. Future studies involving larger and more diverse cohorts are warranted to find areas for improvement in recruitment, retention, and diversity.

Recurrent aortic insufficiency after emergency surgery for acute type A aortic dissection with aortic root preservation.

OBJECTIVE: Patients with acute type A aortic dissection demonstrate a wide range of aortic insufficiency. Outcomes after valve resuspension and root repair are not well studied in the long term. We evaluated the long-term effects of preoperative aortic insufficiency in patients undergoing emergency root-preserving surgery for acute type A aortic dissection. METHODS: From 2002 to 2017, 558 of 776 patients with acute type A aortic dissection underwent native aortic valve resuspension and root reconstruction. Patients were stratified into 4 groups by preoperative aortic insufficiency grade (n = 539): aortic insufficiency less than 2+ (n = 348), aortic insufficiency = 2+ (n = 72), aortic insufficiency = 3+ (n = 49), and aortic insufficiency = 4+ (n = 70). Multivariable ordinal longitudinal mixed effects and multi-state transition models were used to assess risk factors for recurrent aortic insufficiency. RESULTS: The prevalence of cardiogenic shock in patients presenting with preoperative aortic insufficiency less than 2+, 2+, 3+, and 4+ was 53 of 348 (15.2%), 12 of 72 (16.7%), 10 of 49 (20.4%), and 24 of 70 (34.3%), respectively (P = .002). Postoperatively, 94.0% of patients had aortic insufficiency 1+ or less at discharge. Operative mortality was 34 of 348 (9.8%), 10 of 72 (13.9%), 6 of 49 (12.2%), and 12 of 70 (17.1%) (P = .303). In an ordinal mixed effects model, preoperative aortic insufficiency was associated with more severe postoperative aortic insufficiency. The multi-state transition model demonstrated that severe aortic insufficiency was associated with progression from no to mild aortic insufficiency (hazard ratio, 2.14; 95% confidence interval, 1.35-3.38), and progression from mild to moderate aortic insufficiency (hazard ratio, 5.70; 95% confidence interval, 1.88-17.30). CONCLUSIONS: Preoperative aortic insufficiency is an important predictor of recurrent aortic insufficiency in patients undergoing valve resuspension with root reconstruction for emergency acute type A aortic dissection repair. Increased echocardiographic surveillance for recurrent aortic insufficiency may be warranted in this cohort.

Coronary Artery Bypass Grafting in Cardiogenic Shock: Decision-Making, Management Options, and Outcomes.

Coronary artery bypass grafting is a highly efficacious mode of myocardial revascularization that reduces mortality from ischemic heart disease. The patient presenting after acute myocardial infarction in cardiogenic shock presents a unique challenge. Early revascularization is proven to reduce mortality, but many questions remain, including the optimal mode and extent of revascularization, the role of mechanical circulatory support, and which patients are candidates for surgical intervention. Unprecedented attention to the outcomes of cardiac surgery means decisions about the management of the acute myocardial infarction in cardiogenic shock patients are influenced by risk aversion. The authors here review this topic to arm the reader with a comprehensive understanding of the literature to better guide surgical decision-making and perioperative management.

Social media forensics applied to assessment of post-critical incident social reaction: The case of the 2017 Manchester Arena terrorist attack.

Forensic science is constantly evolving and transforming, reflecting the numerous technological innovations of recent decades. There are, however, continuing issues with the use of digital data, such as the difficulty of handling large-scale collections of text data. As one way of dealing with this problem, we used machine-learning techniques, particularly natural language processing and Latent Dirichlet Allocation (LDA) topic modeling, to create an unsupervised text reduction method that was then used to study social reactions in the aftermath of the 2017 Manchester Arena bombing. Our database was a set of millions of messages posted on Twitter in the first 24 h after the attack. The findings show that our method improves on the tools presently used by law enforcement and other agencies to monitor social media, particularly following an event that is likely to create widespread social reaction. For example, it makes it possible to track different types of social reactions over time and to identify subevents that have a significant impact on public perceptions.

Fate of the Preserved Sinuses of Valsalva After Emergency Repair for Acute Type A Aortic Dissection.

BACKGROUND: Patients with acute type A aortic dissection (ATAAD) present with heterogeneous involvement of the aortic root complex. Despite this variation, the aortic root can usually be preserved the majority of the time by Teflon (WL Gore, Newark, DE) inlay patch reconstruction of the dissected sinuses of Valsalva (SOV). In this study, we report the long term anatomic, functional, and clinical outcomes associated with the preserved SOV after surgery for ATAAD. METHODS: From 2002-2017, of 776 emergency ATAAD operations at a single institution, 558 (71.9%) underwent valve resuspension with SOV preservation. Echocardiography reports were reviewed to obtain postoperative SOV dimensions. Cumulative incidence of SOV dilation ≥ 4 5mm was calculated using the Fine-Gray method with death as a competing risk. Repeated-measures linear mixed effects model was used to determine risk factors for SOV growth over time. RESULTS: During the follow-up period, 62 of 558 (11.1%) patients developed SOV diameter ≥ 45 mm. Cumulative incidence of SOV dilation ≥ 45 mm at 1, 5, and 10 years was 5.5%, 12.4%, and 18.9% respectively. In a multivariable Cox regression model, preoperative SOV diameter ≥ 45 mm was associated with a hazard ratio of 14.11 (95% confidence interval 7.03-31.62) for postoperative SOV dilation ≥ 45 mm. In a repeated-measures linear mixed effects model, preoperative and discharge SOV diameter were significant predictors of SOV dilation. Postoperative time course was also identified as significant indicating growth over time. CONCLUSIONS: The preserved sinuses of Valsalva after surgery for ATAAD may be prone to progressive dilatation over time. Closer echocardiographic surveillance may be warranted in these patients.