Causal network topology analysis: Characterizing causal context for risk management.

The ways that risk assessments are commonly performed in organizations have limitations that undermine their quality. They typically focus on individual risk events one at a time but are weak at integrating their relevant causal context, into decision-making processes. Network topology analysis has previously been applied to address this weakness through quantitatively characterizing the importance of the causal interactions of risk events. However, there remains a lack of both clarity and consistency in terminology, methods, and interpretation of the results of this approach. This paper presents and formalizes causal network topology analysis, a methodology that contributes to (1) characterizing the causal context of a risk event to inform its management, (2) articulating the ontological concepts underpinning a repeatable topology network analysis, and (3) justifying the selection and usage of network metrics for this purpose. The theory and methodology are discussed, and an exemplar application to a mining project feasibility study is presented.

Physician assessment of aortic stenosis severity, quantitative parameters, and long-term outcomes: Results from the KP-VALVE project.

BACKGROUND: Contemporary outcomes for aortic stenosis (AS) and the association between physician-assessed AS severity and quantitative parameters is poorly understood. We aimed to evaluate AS natural history, compare outcomes for physicians' AS assessment vs. quantitative parameters, and identify AS parameters with the most explanatory power. METHODS: We ascertained physician-assessed AS severity, echocardiographic parameters, and clinical data for 546,769 patients from 2008-2018, examined multivariable associations of physician-assessed AS severity and number of quantitative severe AS parameters with death, cardiovascular hospitalization, and aortic valve replacement, and estimated the relative contribution of different quantitative AS parameters on outcomes. RESULTS: Among 49,604 AS patients (mean [SD] age 77 [11] years), 17.6% had moderate, 3.6% moderate-severe, and 9.4% severe AS. During median 3.7 [IQR 1.7-6.8] years, physician-assessed AS severity strongly correlated with outcomes, with moderate AS patients tracking closest to mild AS, and moderate-to-severe AS patients more comparable to severe AS. Although the number of quantitative severe AS parameters strongly predicted outcomes (adjusted HR [95% CI] for death 1.40 [1.34-1.46], 1.70 [1.56-1.85], and 1.78 [1.63-1.94] for 1, 2, and 3 parameters, respectively), aortic valve area <1.0 cm2 was the most frequent severe AS parameter, explained the largest relative contribution (67%), and was common in patients classified as moderate (21%) or moderate-severe (56%) AS. CONCLUSIONS: Physician-assessed AS severity predicts outcomes, with cumulative effects for each severe AS parameter. Moderate AS includes a wide spectrum of patients, with discordant AVA <1.0 cm2 being both common and predictive. Better identification of non-classical severe AS phenotypes may improve outcomes.

Varietal and environmental influences on organoleptic and cooking quality of water yam (Dioscorea alata) landraces.

BACKGROUND: Yam is a major staple food that provides both energy (starch) and bioactive compounds. However, there is a lack of knowledge on its cooking quality. We have determined the cooking quality of five varieties of water yam (among those most appreciated by consumers), when they were steamed or boiled. The yams were grown in two contrasting locations with regard to pedoclimatic conditions. RESULTS: Ratio of length to mean circumference of the tuber, difficulty to peel, cooking time, color attributes, hardness of steamed pulp, and dry matter (DM) and starch contents significantly varied among varieties. Cooking time and hardness of the cooked pulp, either steamed or boiled, were higher for tubers grown at the drier location, with vertisols, than at the rainy one, with a ferralitic soil. The raw pulp was richer in starch at the rainy location. We found no correlation between either textural properties or DM and the cooking time. A slight (r = 0.44) but significant correlation was recorded between the DM of the raw pulp and the hardness of the steamed product. CONCLUSION: We propose a comprehensive multicriteria approach for determination of yam cooking quality, textural properties, color attributes and chemical composition, along with varietal and environmental influences. This approach takes into consideration the complexity of food quality, allows a better understanding of its determinants and provides a basis for useful guidelines for breeders. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Outcomes of Adults with Severe Aortic Stenosis Undergoing Urgent or Emergent vs. Elective Transcatheter Aortic Valve Replacement Within an Integrated Health Care Delivery System.

Background: Transcatheter aortic valve replacement (TAVR) may be used to urgently or emergently treat severe aortic stenosis, but outcomes for this high-risk population have not been well-characterized. We sought to describe the incidence, clinical characteristics, and outcomes of patients undergoing urgent or emergent vs. elective TAVR. Methods: We identified all adults who received TAVR for primary aortic stenosis between 2013 and 2019 within an integrated health care delivery system in Northern California. Elective or urgent/emergent procedure status was based on standard Society of Thoracic Surgeons definitions. Data were obtained from electronic health records, the Society of Thoracic Surgeons-American College of Cardiology Transcatheter Valve Therapy Registry, and state/national reporting databases. Logistic regression and Cox proportional hazard models were performed. Results: Among 1564 eligible adults that underwent TAVR, 81 (5.2%) were classified as urgent/emergent. These patients were more likely to have heart failure (63.0% vs. 47.4%), reduced left ventricular ejection fraction (21.0% vs. 11.8%), or a prior aortic valve balloon valvuloplasty (13.6% vs. 5.0%) and experienced higher unadjusted rates of 30-day and 1-year morbidity and mortality. Urgent/emergent TAVR status was independently associated with non-improved quality of life at 30-days (hazard ratio, 4.87; p < 0.01) and acute kidney injury within 1-year post-TAVR (hazard ratio, 2.11; p = 0.01). There was not a significant difference in adjusted 1-year mortality with urgent/emergent TAVR. Conclusions: Urgent/emergent TAVR status was uncommon and associated with high-risk clinical features and higher unadjusted rates of short- and long-term morbidity and mortality. Procedure status may be useful to identify patients less likely to experience significant short term improvement in health-related quality of life post-TAVR.

Temporal trends in the prevalence and severity of aortic stenosis within a contemporary and diverse community-based cohort.

BACKGROUND: Data on the epidemiology of aortic stenosis (AS) are primarily derived from single center experiences and administrative claims data that do not delineate by degree of disease severity. METHODS: An observational cohort study of adults with echocardiographic AS was conducted January 1st, 2013-December 31st, 2019 at an integrated health system. The presence/grade of AS was based on physician interpretation of echocardiograms. RESULTS: A total of 66,992 echocardiogram reports for 37,228 individuals were identified. The mean ± standard deviation (SD) age was 77.5 ± 10.5, 50.5% (N = 18,816) were women, and 67.2% (N = 25,016) were non-Hispanic whites. The age-standardized AS prevalence increased from 589 (95% Confidence Interval [CI] 580-598) to 754 (95% CI 744-764) cases per 100,000 during the study period. The age-standardized AS prevalences were similar in magnitude among non-Hispanic whites (820, 95% CI 806-834), non-Hispanic blacks (728, 95% CI 687-769), and Hispanics (789, 95% CI 759-819) and substantially lower for Asian/Pacific Islanders (511, 95% CI 489-533). Finally, the distribution of AS by degree of severity remained relatively unchanged over time. CONCLUSIONS AND RELEVANCE: The population prevalence of AS has grown considerably over a short timeframe although the distribution of AS severity has remained stable.

Prioritization of hazards for risk and resilience management through elicitation of expert judgement.

Risk assessment in communities or regions typically relies on the determination of hazard scenarios and an evaluation of their impact on local systems and structures. One of the challenges of risk assessment for infrastructure operators is how to identify the most critical scenarios that are likely to represent unacceptable risks to such assets in a given time frame. This study develops a novel approach for prioritizing hazards for the risk assessment of infrastructure. Central to the proposed methodology is an expert elicitation technique termed paired comparison which is based on a formal mathematical technique for quantifying the range and variance in the judgements of a group of stakeholders. The methodology is applied here to identify and rank natural and operational hazard scenarios that could cause serious disruption or have disastrous effects to the infrastructure in the transnational Øresund region over a period of 5 years. The application highlighted substantial divergences of views among the stakeholders on identifying a single 'most critical' natural or operational hazard scenario. Despite these differences, it was possible to flag up certain cases as critical among the natural hazard scenarios, and others among the operational hazards.

Improved temporal contrast of streak camera measurements with periodic shadowing.

Periodic shadowing, a concept used in spectroscopy for stray light reduction, has been implemented to improve the temporal contrast of streak camera imaging. The capabilities of this technique are first proven by imaging elastically scattered picosecond laser pulses and are further applied to fluorescence lifetime imaging, where more accurate descriptions of fluorescence decay curves were observed. This all-optical approach can be adapted to various streak camera imaging systems, resulting in a robust technique to minimize space-charge induced temporal dispersion in streak cameras while maintaining temporal coverage and spatial information.

ST-Segment Elevation Myocardial Infarction and Out-of-Hospital Cardiac Arrest: Contemporary Management From the Multicenter START Registry.

BACKGROUND: Recent studies suggest that primary percutaneous coronary intervention (PCI) and targeted temperature management (TTM) improve outcome in ST-segment elevation myocardial infarction (STEMI) complicated by out-of-hospital cardiac arrest (OHCA). The objective of this study was to evaluate a contemporary series of patients with STEMI and OHCA to characterize treatment approaches and predictors of neurologic outcome. METHODS: From January 2009 through November 2012, a total of 239 patients who underwent emergent coronary angiography at 10 medical centers across the United States were enrolled. All patients suffered OHCA with STEMI on either the prehospital or post-resuscitation electrocardiogram. Neurologic outcome was assessed using the cerebral performance category (CPC) score. Predictors of neurologic outcome were determined using multivariate logistic regression analysis. The primary endpoint was in-hospital survival with good neurologic function (CPC score 1 or 2). RESULTS: Mean age was 60 ± 13 years, 72% were male, and the majority of patients had a history of cardiovascular event. Initial rhythm was ventricular fibrillation in 72%. At hospital presentation, 76% of patients were intubated, 37% were in cardiogenic shock, and 33% were receiving vasopressors. Primary PCI was performed in 74%, with an average door-to-balloon time of 95 ± 77 minutes, and TTM was used in 51%. Forty-four percent of patients had full neurologic recovery (CPC score 1) and 55% had good neurologic function. Overall in-hospital survival rate was 66%. Independent predictors of in-hospital survival with good neurologic function were: receiving bystander cardiopulmonary resuscitation, location of arrest, receiving drug-eluting stents, and not experiencing a recurrent cardiac arrest. CONCLUSIONS: Short-term survival for patients with STEMI and OHCA undergoing emergent coronary angiography and revascularization with TTM in this contemporary, multicenter registry was high and neurologic outcome was good in more than half of patients.

Cancellation of the Cardiac Catheterization Lab After Activation for ST-Segment-Elevation Myocardial Infarction.

BACKGROUND: Prehospital ECG-based cardiac catheterization laboratory (CCL) activation for ST-segment-elevation myocardial infarction reduces door-to-balloon times, but CCL cancellations (CCLX) remain a challenging problem. We examined the reasons for CCLX, clinical characteristics, and outcomes of patients presenting as ST-segment-elevation myocardial infarction activations who receive emergent coronary angiography (EA) compared with CCLX. METHODS AND RESULTS: We reviewed all consecutive CCL activations between January 1, 2012, and December 31, 2014 (n=1332). Data were analyzed comparing 2 groups stratified as EA (n=466) versus CCLX (n=866; 65%). Reasons for CCLX included bundle branch block (21%), poor-quality prehospital ECG (18%), non-ST-segment-elevation myocardial infarction ST changes (18%), repolarization abnormality (13%), and arrhythmia (8%). A multivariate logistic regression model using age, peak troponin, and initial ECG findings had a high discriminatory value for determining EA versus CCLX (C statistic, 0.985). CCLX subjects were older and more likely to be women, have prior coronary artery bypass grafting, or a paced rhythm ( P<0.0001 for all). All-cause mortality did not differ between groups at 1 year or during the study period (mean follow-up, 2.186±1.167 years; 15.8% EA versus 16.2% CCLX; P=0.9377). Cardiac death was higher in the EA group (11.8% versus 3.0%; P<0.0001). After adjusting for clinical variables associated with survival, CCLX was associated with an increased risk for all-cause mortality during the study period (hazard ratio, 1.82; 95% CI, 1.28-2.59; P=0.0009). CONCLUSIONS: In this study, prehospital ECG without overreading or transmission lead to frequent CCLX. CCLX subjects differ with regard to age, sex, risk factors, and comorbidities. However, CCLX patients represent a high-risk population, with frequently positive cardiac enzymes and similar short- and long-term mortality compared with EA. Further studies are needed to determine how quality improvement initiatives can lower the rates of CCLX and influence clinical outcomes.

A Decade of Progress in Regional ST-Segment Elevation Myocardial Infarction Systems of Care: A Tale of Two Cities.

Over the past 20 years, care for patients with ST-elevation myocardial infarction (STEMI) has rapidly evolved, not just in terms of how patients are treated, but where patients are treated. The advent of regional STEMI systems of care has decreased the number of "eligible but untreated" patients while improving access to primary percutaneous coronary intervention for patients. These regional STEMI systems of care have consistently demonstrated that rapid transport of STEMI patients is safe and effective, and have shown marked improvements in a variety of clinical outcomes. However, no two STEMI systems are alike, and each must be tailored to the unique geographic, political, and socioeconomic challenges of the region. This article takes an in-depth look at two of the earliest STEMI systems within the United States: the Minneapolis Heart Institute and the Los Angeles County STEMI receiving network.

A Closer Look at Fractional Flow Reserve in Complex Anatomic Subsets: Left Main Disease, Bifurcation Lesions, and Saphenous Vein Grafts.

Fractional flow reserve (FFR) is a well-validated tool for determining the functional significance of a coronary artery stenosis, facilitating clinical decisions regarding the need for revascularization. FFR-guided revascularization improves clinical and economic outcomes. However, its application remains challenging in certain complex anatomic subsets, including left main coronary artery stenosis, bifurcation disease, and saphenous vein graft disease. This article reviews recent data supporting the use of FFR in these complex anatomic subsets.

False Activations for ST-Segment Elevation Myocardial Infarction.

First-medical-contact-to-device (FMC2D) times have improved over the past decade, as have clinical outcomes for patients presenting with ST-elevation myocardial infarction (STEMI). However, with improvements in FMC2D times, false activation of the cardiac catheterization laboratory (CCL) has become a challenging problem. The authors define false activation as any patient who does not warrant emergent coronary angiography for STEMI. In addition to clinical outcome measures for these patients, STEMI systems should collect data regarding the total number of CCL activations, the total number of emergency coronary angiograms, and the number revascularization procedures performed.

A "prospective" and "retrospective" view of the hazards of a career in interventional cardiology.

Surveyed interventional cardiologists reported frequent occupation-related health hazards including orthopedic injury (49.4%), radiation-related skin disease (4.8%), cataracts (5.5%), and hematologic and malignant conditions (4.8%) Further advances are needed to increase operator and staff safety to prevent future orthopedic injuries and radiation-related diseases. Each individual interventional cardiologist needs to weigh the hazards of the profession with the benefits which are substantial as well.

Novel Biomarkers of Cardiac Stress, Cardiovascular Dysfunction, and Outcomes in HIV-Infected Individuals.

OBJECTIVES: This study sought to determine whether biomarkers ST2, growth differentiation factor (GDF)-15, N-terminal pro-B-type natriuretic peptide (NT-proBNP), and high-sensitivity troponin I are elevated in patients infected with human immunodeficiency virus (HIV) and are associated with cardiovascular dysfunction and all-cause mortality. BACKGROUND: HIV-infected patients have high rates of cardiovascular disease. Markers of myocardial stress may identify at-risk patients and provide additional prognostic information. METHODS: Biomarkers and echocardiograms were assessed in 332 HIV-infected patients and 50 age- and sex-matched control subjects. Left ventricular systolic dysfunction was defined as ejection fraction <50%, diastolic dysfunction (DD) as stage 1 or higher, and pulmonary hypertension as pulmonary artery systolic pressure ≥35 mm Hg. Mortality data were obtained from the National Death Index. RESULTS: Patients with HIV had a median age of 49 years, and 80% were male. Compared with control subjects, HIV-infected patients had higher adjusted percent estimates of all biomarkers except ST2 and interleukin-6. Among HIV-infected patients, 45% had DD; only ST2 was associated with DD (relative risk [RR]: 1.36; p = 0.047). Left ventricular systolic dysfunction was rare in this cohort (5%). Pulmonary hypertension was present in 27% of HIV-infected patients and was associated with GDF-15 (RR: 1.18; p = 0.04), NT-proBNP (RR: 1.18; p = 0.007), and cystatin C (RR: 1.54; p = 0.03). Thirty-eight deaths occurred among HIV-infected patients over a median of 6.1 years. In adjusted analysis, all-cause mortality was independently predicted by ST2 (hazard ratio [HR]: 2.04; p = 0.010), GDF-15 (HR: 1.42; p = 0.0054), high-sensitivity C-reactive protein (HR: 1.25; p = 0.023), and D-dimer (HR: 1.49; p = 0.029). Relationships were unchanged when analyses were restricted to virally suppressed HIV-infected patients receiving antiretroviral therapy. CONCLUSIONS: Among HIV-infected patients, ST2 and GDF-15 were associated with both cardiovascular dysfunction and all-cause mortality, and these variables may be useful at identifying those at risk for developing cardiovascular events and death.

Mitral Annular and Coronary Artery Calcification Are Associated with Mortality in HIV-Infected Individuals.

BACKGROUND: HIV infection increases cardiovascular risk. Coronary artery calcification (CAC) and mitral annular calcification (MAC) identify patients at risk for cardiovascular disease (CVD). The purpose of this study was to examine the association between MAC, CAC and mortality in HIV-infected individuals. METHODS AND RESULTS: We studied 152 asymptomatic HIV-infected individuals with transthoracic echocardiography (TTE) and computed tomography (CT). MAC was identified on TTE using standardized criteria. Presence of CAC, CAC score and CAC percentiles were determined using the modified Agatston criteria. Mortality data was obtained from the Social Security and National Death Indices (SSDI/NDI). The median age was 49 years; 87% were male. The median duration of HIV was 16 years; 84% took antiretroviral therapy; 64% had an undetectable viral load. CVD risk factors included hypertension (35%), smoking (62%) and dyslipidemia (35%). Twenty-five percent of individuals had MAC, and 42% had CAC. Over a median follow-up of 8 years, 11 subjects died. Subjects with CAC had significantly higher mortality compared to those with MAC only or no MAC. The Harrell's C-statistic of CAC was 0.66 and increased to 0.75 when MAC was added (p = 0.05). MAC, prior CVD, age and HIV viral load were independently associated with higher age- and gender-adjusted CAC percentiles in an adjusted model (p < 0.05 for all). CONCLUSION: In HIV patients, the presence of MAC, traditional risk factors and HIV viral load were independently associated with CAC. Presence of CAC and MAC may be useful in identifying HIV-infected individuals at higher risk for death.