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Background: Cerebrospinal fluid creatine kinase BB isoenzyme (CSF CK-BB) after cardiac arrest (CA) has been shown to have a high positive predictive value for poor neurological outcome, but it has not been evaluated in the setting of targeted temperature management (TTM) and modern CA care. We aimed to evaluate CSF CK-BB as a prognostic biomarker after CA. Methods: We performed a retrospective cohort study of patients with CA admitted between 2010 and 2020 to a three-hospital health system who remained comatose and had CSF CK-BB assayed between 36 and 84 h after CA. We examined the proportion of patients at hospital discharge who achieved favorable or intermediate neurological outcome, defined as Cerebral Performance Category score of 1–3, compared with those with poor outcome (Cerebral Performance Category score 4–5) for various CSF CK-BB thresholds. We also evaluated additive value of bilateral absence of somatosensory evoked potentials (SSEPs). Results: Among 214 eligible patients, the mean age was 54.7 ± 4.8 years, 72% of patients were male, 33% were nonwhite, 17% had shockable rhythm, 90% were out-of-hospital CA, and 83% received TTM. A total of 19 (9%) awakened. CSF CK-BB ≥ 230 U/L predicted a poor outcome at hospital discharge, with a specificity of 100% (95% confidence interval [CI] 82–100%) and sensitivity of 69% (95% CI 62–76%). When combined with bilaterally absent N20 response on SSEP, specificity remained 100% while sensitivity increased to 80% (95% CI 73–85%). Discordant CK-BB and SSEP findings were seen in 13 (9%) patients. Conclusions: Cerebrospinal fluid creatine kinase BB isoenzyme levels accurately predicted poor neurological outcome among CA survivors treated with TTM. The CSF CK-BB cutoff of 230 U/L optimizes sensitivity to 69% while maintaining a specificity of 100%. CSF CK-BB could be a useful addition to multimodal neurological prognostication after CA. [ABSTRACT FROM AUTHOR]

Purpose of Review: The athlete's heart exhibits unique structural and functional adaptations in the setting of strenuous and repetitive athletic training which may be similarly found in pathologic states. The purpose of this review is to highlight the morphologic and functional changes associated with the athlete's heart, with a focus upon the insights that echocardiography provides into exercise-induced cardiac remodeling. Recent Findings: Recent studies are aiming to investigate the long-term effects and clinical consequences of an athlete's heart. The "gray-zone" continues to pose a clinical challenge and may indicate scenarios where additional imaging modalities, or longitudinal follow-up, provide a definitive answer. Summary: Echocardiography is likely to remain the first-line imaging modality for the cardiac evaluation of elite athletes. Multimodality imaging combined with outcome and long-term follow-up studies both during training and after retirement in both men and women may help further clarify the remaining mysteries in the coming years. [ABSTRACT FROM AUTHOR]

A new luminescent three dimensional (3D) supramolecular coordination polymer (CP) with formula [Cd2(L)2(bib)(H2O)2] (1) (H2L = 4,4′-(1,2-phenlenebis(methyleneoxy))dibenzoic acid and bib = 1,4- bis(1-imidazoly)benzene), has been synthesized and characterized. The single crystal X-ray analysis revealed that 1 possess one-dimensional (1D) ribbon-like motifs. Through intermolecular hydrogen bonding, the motifs produced a 2D supramolecular layer and further, π···π interactions generated a 3D supramolecular framework. In addition, the bib linkers stretch across the loop to generate a polyrotaxane-like structure. Polymer 1 behaves as a luminescent sensor for antibiotics, it sensitively and selectively detects sulfamethazine (SMZ) with a low detection limit of 1.05 ppm and a high KSV value of 2.98 × 103 M− 1. With the aid of theoretical calculations plausible luminescence sensing mechanism of 1 to detect antibiotics has been proposed. It is suggested that electron/energy transfer and weak CP-antibiotics interactions are responsible for variation in luminescence intensity of the polymer. A 3D supramolecular Cd(II)-coordination polymer synthesized and used as a luminescent sensor for detection of sulfamethazine. [ABSTRACT FROM AUTHOR]

Echocardiographic evaluation of left ventricular diastolic function relies on a multi-pronged algorithm, which incorporates Doppler-based and volumetric parameters. Integration of clinical data in diastolic assessment is recommended, though not clearly outlined. We sought to develop an automated tool for diastolic function, compare its performance to human-generated diagnoses and identify the common sources of error. Our software tool is based on the 2016 diastolic guidelines algorithm, which uses 8 parameters as input, with 10 conditions as the logic and 5 possible outputs as final diagnoses. Initially, we prospectively studied 563 patients whose diastolic function was independently evaluated by an expert echocardiographer and by the automated tool. Incongruent cases were further analyzed, after which features of myocardial disease were integrated into a refined version of the software that was tested in an independent cohort of 1106 patients. In the initial analysis, 202/563 grades (36%) were incongruent between the automated and human reads, with the highest rate of discordance for mild and indeterminate categories. In 17% of cases, human diagnoses differed from that dictated by the algorithm due to integration of clinical factors. Follow-up analysis using the refined automated tool did not improve the discordance rate (440/1106; 40%). There was more discordance in cases of: age > 40 years, impaired mitral inflow patterns (E/A < 0.8) and reduced mitral e' values. Further analysis revealed differences in how readers interpreted the interaction between these factors and diastolic function, which could not be incorporated into the automated tool. In conclusion, although assessment of diastolic function relies on an algorithm that can be automated, this algorithm does not include clear guidance on how to incorporate age, or age-related changes in Doppler-based parameters, often resulting in discordant diagnoses. Standardized interpretation of these factors is needed to improve the reproducibility of diastolic function grading by human readers and the accuracy of the automated classification. [ABSTRACT FROM AUTHOR]

Background: Tracheostomy represents one important and value-laden treatment decision after severe acute brain injury (SABI). Whether to pursue this life-sustaining treatment typically hinges on intense conversations between family and clinicians. The aim of this study was, among a cohort of patient who had undergone tracheostomy after SABI, to explore the long-term reflections of patients and their families as they look back on this decision. Methods: For this qualitative study, we reviewed the electronic medical records of patients with SABI who underwent tracheostomy. We included all patients who were admitted to our 30-bed neuro-intensive care unit with SABI and underwent tracheostomy between November 2017 and October 2019. Using purposive sampling, we invited survivors and family members to participate in telephone interviews greater than 3 months after SABI until thematic saturation was reached. Interviews were audiotaped, transcribed, and analyzed by using thematic analysis. Results: Overall, 38 patients with SABI in the neuro-intensive care unit underwent tracheostomy. The mean age of patients was 49 (range 18–81), with 19 of 38 patients diagnosed with traumatic brain injury and 19 of 38 with stroke. We interviewed 20 family members of 18 of 38 patients at a mean of 16 (SD 9) months after hospitalization. The mean patient age among those with an interview was 50 (range 18–76); the mean modified Rankin Scale score (mRS) was 4.7 (SD 0.8) at hospital discharge. At the time of the interview, ten patients lived at home and two in a skilled nursing facility and had a mean mRS of 2.6 (SD 0.9), and six had died. As families reflected on the decision to proceed with a tracheostomy, two themes emerged. First, families did not remember tracheostomy as a choice because the uncertain chance of recovery rendered the certain alternative of death unacceptable or because they valued survival above all and therefore could not perceive an alternative to life-sustaining treatment. Second, families identified a fundamental need to receive supportive, consistent communication centering around compassion, clarity, and hope. When this need was met, families were able to reflect on the tracheostomy decision with peace, regardless of their loved one's eventual outcome. Conclusions: After SABI, prognostic uncertainty almost transcends the concept of choice. Families who proceeded with a tracheostomy saw it as the only option at the time. High-quality communication may mitigate the stress surrounding this high-stakes decision. [ABSTRACT FROM AUTHOR]

Transillumination (TI) is a new 3D rendering tool that uses a freely movable virtual light source to enhance depth, contours, and image detail. The TI model was recently modified to allow the operator adjust the degree of transparency of both cardiac and extra-cardiac structures. While the addition of transparency was shown to significantly improve quality in 3D transesophageal imaging, this has not yet been shown for transthoracic (TTE) imaging. We prospectively studied 35 patients who underwent clinically indicated TTE with standard 3D acquisition, as well as TI with and without transparency. Six experienced echocardiographers were shown images of all three display types in random order. Each image was scored independently using a Likert Scale while assessing each of the following aspects: ability to identify anatomy or pathology, depth perception, degree of anatomic detail, and border delineation. All experts perceived an incremental value of the transparency mode, compared to TI without transparency and standard 3D rendering, in terms of ability to identify anatomy or pathology (4.15 ± 0.97 vs. 3.88 ± 0.99 vs. 2.52 ± 1.41, p < 0.01), depth perception (4.33 ± 0.78 vs. 3.88 ± 0.82 vs. 2.29 ± 1.07, p < 0.01), degree of anatomic detail (4.08 ± 1.0 vs. 3.89 ± 0.79 vs. 2.31 ± 1.08, p < 0.01), and border delineation (4.44 ± 0.80 vs. 3.90 ± 0.78 vs. 2.42 ± 1.13, p < 0.01). Compared to standard 3D and TI renderings of TTE images, the addition of transparency significantly improves both image quality and diagnostic confidence. [ABSTRACT FROM AUTHOR]

As clinicians have gained experience in treating patients with the novel SARS-CoV-2 (COVID-19) virus, mortality rates for patients with acute COVID-19 infection have decreased. The Centers for Disease Control (CDC) has identified the African American population as having increased risk of COVID-19 associated mortality, however little is known about echocardiographic markers associated with increased mortality in this patient population. We aimed to compare the clinical and echocardiographic features of a predominantly African American patient cohort hospitalized with acute COVID-19 infection during the first (March–June 2020) and second (September–December 2020) waves of the COVID-19 pandemic, and to investigate which parameters are most strongly associated with composite all-cause mortality. We performed consecutive transthoracic echocardiograms (TTEs) on 105 patients admitted with acute COVID-19 infection during the first wave and 129 patients admitted during the second wave. TTE parameters including left ventricular ejection fraction (LVEF), left ventricular global longitudinal strain (LVGLS), right ventricular global longitudinal strain (RVGLS), right ventricular free-wall strain (RVFWS), and right ventricular basal diameter (RVBD) were compared between the two groups. Clinical and demographic characteristics including underlying co-morbidities, biomarkers, in-hospital treatment regimens, and outcomes were collected and analyzed. Univariable and multivariable analyses were performed to determine variables associated with all-cause mortality. There were no significant differences between the two waves in terms of age, gender, BMI, or race. Overall all-cause mortality was 35.2% for the first wave compared to 14.7% for the second wave (p < 0.001). Previous medical conditions were similar between the two waves with the exception of underlying lung disease (41.9% vs. 29.5%, p = 0.047). Echocardiographic parameters were significantly more abnormal in the first wave compared to the second: LVGLS (− 17.1 ± 5.0 vs. − 18.9 ± 4.8, p = 0.02), RVGLS (− 15.7 ± 5.9% vs. − 19.0 ± 5.9%, p < 0.001), RVFWS (− 19.5 ± 6.8% vs. − 23.2 ± 6.9%, p = 0.001), and RVBD (4.5 ± 0.8 vs. 3.9 ± 0.7 cm, p < 0.001). Stepwise multivariable logistic analysis showed mechanical ventilation, RVFWS, and RVGLS to be independently associated with mortality. In a predominantly African American patient population on the south side of Chicago, the clinical and echocardiographic features of patients hospitalized with acute COVID-19 infection demonstrated marked improvement from the first to the second wave of the pandemic, with a significant decrease in all-cause mortality. Possible explanations include implementation of evidence-based therapies, changes in echocardiographic practices, and behavioral changes in our patient population. Mechanical ventilation and right-sided strain-based markers were independently associated with mortality. [ABSTRACT FROM AUTHOR]

Cardiac sarcoidosis (CS) is known to be associated with ventricular tachycardia (VT); however, most investigations to date have focused on patients with known extra-cardiac sarcoidosis. The presence of CS is typically evaluated using 18F-fluorodeoxyglucose (18F-FDG) uptake on cardiac positron emission tomography (PET) or late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR). In this study, we sought to determine the prevalence of primary CS and the relationship between myocardial 18F-FDG uptake and LGE in patients with VT without known sarcoidosis. We retrospectively identified 67 patients without known sarcoidosis or active ischemic heart disease (i.e. significant ischemic disease that had not been previously revascularized) referred for both CMR and PET for evaluation of VT. Standard cine- and LGE- CMR and cardiac PET protocols were used. Myocardial LGE was defined as signal intensity > 5 SDs above the mean signal intensity of normal myocardium. Cardiac PET images were considered positive if there was focal myocardial 18F-FDG uptake having greater activity than the left ventricular blood pool. 45 patients (67%) had LGE, while only 4 (6%) had myocardial FDG uptake. Nine percent of patients with LGE had FDG-uptake while none without LGE did, and 10% of the cohort had indeterminate FDG uptake presumably from poor dietary preparation. Of those with both FDG uptake and LGE, 3/4 ultimately received a clinical diagnosis of CS. 4.5% of patients without previously known sarcoidosis or active ischemic heart disease presenting with VT have newly diagnosed CS. Detection of CS can be increased using a CMR first approach followed by cardiac PET for patients with non-ischemic LGE. [ABSTRACT FROM AUTHOR]

Purpose of the Review: The purpose of this review is to outline the role of echocardiography in identifying patients at increased cardiovascular risk for cancer treatment-associated cardiotoxicity. Recent Findings: With a wide array of cancer therapeutics, a variety echocardiographic cardiotoxicity phenotypes have been identified. Recent consensus statements from several professional societies have provided a framework for risk assessment prior to cancer therapy that involves assessment and optimization of cardiac risk factors but also involves echocardiographic evaluation of left ventricular (LV) function at baseline, during, and after treatment. While newer echocardiographic techniques such as global longitudinal strain are key to detecting subclinical cardiotoxicity, it is as yet unclear if strain-directed initiation of cardioprotective medications will result in better outcomes. This is the subject of an ongoing clinical trial, the results of which are eagerly awaited. Given the serial nature of echocardiographic assessments in the cancer population, the application of automated techniques for ejection fraction and strain may have the potential to further reduce measurement variability and are also subjects of ongoing research. Summary: Echocardiography is the preferred imaging modality for the detection of cardiotoxicity related to cancer therapy. Our expanded understanding of the cardiac side effects of cancer therapy and optimal surveillance strategies for those at risk is predicated on the ascertainment of cardiac outcomes in future clinical trials, for which echocardiography will undoubtedly play a pivotal role. [ABSTRACT FROM AUTHOR]

Global analysis of power system markets project frequency regulation as one of the most profitable ancillary services. It is associated with second-to-second balance of load and frequency within a control area and acquires a principal role in enabling power interchanges while offering better conditions for electricity exchange. In the light of the above, a novel control strategy, namely salp swarm algorithm (SSA)-based model predictive controller, is proposed for frequency regulation of an unequal two-area realistic power system, incorporating solar thermal power plant and conventional thermal plant. Governor dead band, generation rate constraint and transport delay are considered in each control area. Over the past few years, model predictive controller (MPC) has come forward as a prediction-based control strategy for stabilizing dynamical systems while considering non-linearities, system uncertainties and constraints. The MPC parameters are optimized using SSA. The performance of the proposed approach is validated by comparing the dynamic time responses of SSA-optimized MPC with the other SSA-optimized conventional controllers, namely PID, FOPID and cascade PIDN-FOPID controller. The simulation result analysis shows that the proposed optimal MPC outpaces the conventional controllers with respect to peak overshoot, undershoot and settling time of the time responses. A comparative study of various objective functions indicates that, as compared to other indices, integral square error is better for the considered test system. Further, sensitivity analysis reveals the robustiousness of MPC parameters obtained at nominal values and hence is not required to be retuned, against variations in system loading and inertia constant. [ABSTRACT FROM AUTHOR]

Vasodilator-stress CT perfusion imaging in addition to CT coronary angiography (CTCA) may provide a single-test alternative to nuclear stress testing, commonly used to assess hemodynamic significance of stenosis. Another alternative is fractional flow reserve (FFR) calculated from cardiac CT images. We studied the concordance between these two approaches and their relationship to outcomes. We prospectively studied 150 patients with chest pain, who underwent CTCA and regadenoson CT. CTCA images were interpreted for presence and severity of stenosis. Fused 3D displays of subendocardial X-ray attenuation with coronary arteries were created to detect stress perfusion defects (SPD) in each coronary territory. In patients with stenosis > 25%, CT-FFR was quantified. Significant stenosis was determined by: (1) combination of stenosis > 50% with an SPD, (2) CT-FFR ≤ 0.80. Patients were followed-up for 36 ± 25 months for death, myocardial infarction or revascularization. After excluding patients with normal arteries and technical/quality issues, in final analysis of 76 patients, CTCA depicted stenosis > 70% in 13/224 arteries, 50-70% in 24, and < 50% in 187. CT-FFR ≤ 0.80 was found in 41/224 arteries, and combination of SPD with > 50% stenosis in 31/224 arteries. Inter-technique agreement was 89%. Despite high incidence of abnormal CT-FFR (30/76 patients), only 7 patients experienced adverse outcomes; 6/7 also had SPDs. Only 1/9 patients with CT-FFR ≤ 0.80 but normal perfusion had an event. Fusion of CTCA and stress perfusion can help determine the hemodynamic impact of stenosis in one test, in good agreement with CT-FFR. Adding stress CT perfusion analysis may help risk-stratify patients with abnormal CT-FFR. [ABSTRACT FROM AUTHOR]

The linker 1,4-bis(2-methyl-imidazole-yl)-butane (bib) was used to construct two coordination polymers, specifically [Cd(bib)(ipa)]n (1) and [Zn(bib)(tpa)]n (2), in the presence of isophthalic acid (H2ipa) and terephthalic acid (H2tpa), respectively, under solvothermal conditions. Topological analyses reveal that the crystal of complex 1 consists of a 3D threefold interpenetrating network with Schläfli symbol {65.8}, while complex 2 possesses a 2D wavelike layer structure with Schläfli symbol {66}. The photocatalytic properties of both complexes for the degradation of methyl violet have been explored, revealing that complex 2 is a better photocatalyst than 1. A mechanism for the photocatalytic properties of the complexes is proposed, based on the results of density of states (DOS) and partial DOS calculations. [ABSTRACT FROM AUTHOR]

Echocardiographic assessment of left ventricular (LV) filling pressures is performed using a multi-parametric algorithm. Left atrial (LA) strain was recently found to accurately classify the degree of diastolic dysfunction. We hypothesized that LA strain could be used as a stand-alone marker and sought to identify and test a cutoff, which would accurately detect elevated LV pressures. We studied 76 patients with a spectrum of LV function who underwent same-day echocardiogram and invasive left-heart catheterization. Speckle tracking was used to measure peak LA strain. The protocol involved a retrospective derivation group (N = 26) and an independent prospective validation cohort (N = 50) to derive and then test a peak LA strain cutoff which would identify pre-A-wave LV diastolic pressure > 15 mmHg. The guidelines-based assessment of filling pressures and peak LA strain were compared side-by-side against invasive hemodynamic data. In the derivation cohort, receiver-operating characteristic analysis showed area under curve of 0.76 and a peak LA strain cutoff < 20% was identified as optimal to detect elevated filling pressure. In the validation cohort, peak LA strain demonstrated better agreement with the invasive reference (81%) than the guidelines algorithm (72%). The improvement in classification using LA strain compared to the guidelines was more pronounced in subjects with normal LV function (91% versus 81%). In summary, the use of a peak LA strain to estimate elevated LV filling pressures is more accurate than the current guidelines. Incorporation of LA strain into the non-invasive assessment of LV diastolic function may improve the detection of elevated filling pressures. [ABSTRACT FROM AUTHOR]

The current climate in healthcare is increasingly emphasizing a value-based approach to diagnostic testing. Cardiac imaging, including echocardiography, has been a primary target of ongoing reforms in healthcare delivery and reimbursement. The Appropriate Use Criteria (AUC) for echocardiography is a physician-derived tool intended to guide utilization in optimal patient care. To date, the AUC have primarily been employed solely as justification for reimbursement, though evolving broader applications to guide clinical decision-making suggest a far more valuable role in the delivery of high-quality and high-value healthcare. [ABSTRACT FROM AUTHOR]

Purpose of Review: Computed tomography (CT) coronary angiography is a well-validated non-invasive technique for accurate and expedient diagnosis of coronary artery disease (CAD). However, a limitation of coronary CT angiography (CCTA) is its limited capability to identify physiologically significant stenoses, which may eventuate the need for further functional testing. Stress CT myocardial perfusion imaging (CT-MPI) is an emerging technique that has the ability to identify flow-limiting stenoses. Recent Findings: The combination of CCTA coronary and CT-MPI has transformed the modality from a tool to assess anatomy and morphology to a modality capable of simultaneous assessment of coronary stenoses and their physiologic significance. A growing number of studies have demonstrated the feasibility and diagnostic accuracy of CT-MPI in comparison to a number of reference standard modalities for CAD diagnosis, including single-photon emission CT, cardiovascular magnetic resonance imaging, and invasive coronary angiography with and without fractional flow-reserve testing. Summary: While there is still a need for consensus regarding acquisition techniques as well as analysis and interpretation of CT-MPI, with further validation, it is likely to become a powerful adjunctive tool to CCTA in the management of patients with suspected coronary disease. [ABSTRACT FROM AUTHOR]

Opinion statement: With the advent of noninvasive 24-hour ambulatory blood pressure monitoring (ABPM), clinicians have access to a wealth of individualized data for the hypertensive patient. This has led to a greater understanding of the pathophysiology of hypertension and its complications. This tool has provided more precise diagnostic criteria for hypertension and helped discover those with white coat and masked hypertension. Patterns noted on ABPM and correlated with outcomes have allowed for more accurate identification of patients at high risk of cardiovascular (CV) events, and have offered an additional prognostic tool. In addition, ABPM allows for the assessment of the efficacy and adequacy of blood pressure treatment. In the current paper, we will describe the essential components of ABPM, review the evidence detailing the prognostic information that can be derived from its use, highlight clinical scenarios wherein ABPM can offer invaluable diagnostic information, and describe applications of ABPM that evaluate the efficacy of treatment of the hypertensive patient. [ABSTRACT FROM AUTHOR]

Triglycerides are routinely obtained with standard lipid testing, but their role in cardiovascular risk is controversial. An excess of triglycerides is commonly encountered in patients with the metabolic syndrome or diabetes, and represents an excess burden of small, dense low-density lipoproteins (LDLs), which confers additive risk for cardiovascular disease. Current guidelines prioritize LDL targets first, but treatment of triglycerides once LDL targets are achieved bears consideration. Beyond lifestyle modification, potential pharmacologic therapies include statins, fibrates, niacin, omega-3 fatty acids and antidiabetic drugs. There are few trials to date comparing these agents directly in the management of hypertriglyceridemia, but available data seems to demonstrate that the greatest benefit of triglyceride lowering is experienced in a subgroup of patients with an atherogenic lipid profile (elevated triglycerides, low high-density lipoprotein (HDL), elevated small, dense LDL particles). Here, we discuss the current understanding of how triglyceride elevations impart cardiovascular risk, current therapies and the data supporting their use, and ongoing studies to elucidate the degree to which treatment of triglycerides modifies risk of future cardiovascular events. [ABSTRACT FROM AUTHOR]

In this paper we present a novel four parameter continuous univariate distribution that can be motivated from at least two approaches. The first one views the distribution as a generalization of the uniform one that allows for uncertainty specification at the vicinity of its bounds (gradually) represented via two Pareto tails. The second one is that of an asymmetric heavy-tailed, peaked distribution with an unbounded domain with the property that the location of the mode is not uniquely determined but rather is described by a uniform range. Properties of the distribution are described and a maximum likelihood estimation (MLE) procedure for the mode location and the Pareto tails parameters is presented. The procedure is illustrated by means of an i.i.d. sample of standardized log-differences of quarterly monthly US certificate deposit interest rates for the period 1964–2004. The sample is constructed utilizing the Auto-Regressive Conditional Heteroscedastic (ARCH) time series model devised by the Nobel Laureate R.F. Engle (1982). [ABSTRACT FROM AUTHOR]