Comparing reliability of ICD-10-based COVID-19 comorbidity data to manual chart review, a retrospective cross-sectional study.

International Statistical Classification of Disease and Related Health Problems, 10th Revision codes (ICD-10) are used to characterize cohort comorbidities. Recent literature does not demonstrate standardized extraction methods. OBJECTIVE: Compare COVID-19 cohort manual-chart-review and ICD-10-based comorbidity data; characterize the accuracy of different methods of extracting ICD-10-code-based comorbidity, including the temporal accuracy with respect to critical time points such as day of admission. DESIGN: Retrospective cross-sectional study. MEASUREMENTS: ICD-10-based-data performance characteristics relative to manual-chart-review. RESULTS: Discharge billing diagnoses had a sensitivity of 0.82 (95% confidence interval [CI]: 0.79-0.85; comorbidity range: 0.35-0.96). The past medical history table had a sensitivity of 0.72 (95% CI: 0.69-0.76; range: 0.44-0.87). The active problem list had a sensitivity of 0.67 (95% CI: 0.63-0.71; range: 0.47-0.71). On day of admission, the active problem list had a sensitivity of 0.58 (95% CI: 0.54-0.63; range: 0.30-0.68)and past medical history table had a sensitivity of 0.48 (95% CI: 0.43-0.53; range: 0.30-0.56). CONCLUSIONS AND RELEVANCE: ICD-10-based comorbidity data performance varies depending on comorbidity, data source, and time of retrieval; there are notable opportunities for improvement. Future researchers should clearly outline comorbidity data source and validate against manual-chart-review.

Association of race/ethnicity and socioeconomic status with COVID-19 30-day mortality at a Philadelphia medical center using a retrospective cohort study.

COVID-19 has disproportionately affected low-income communities and people of color. Previous studies demonstrated that race/ethnicity and socioeconomic status (SES) are not independently correlated with COVID-19 mortality. The purpose of our study is to determine the effect of race/ethnicity and SES on COVID-19 30-day mortality in a diverse, Philadelphian population. This is a retrospective cohort study in a single-center tertiary care hospital in Philadelphia, PA. The study includes adult patients hospitalized with polymerase-chain-reaction-confirmed COVID-19 between March 1, 2020 and June 6, 2020. The primary outcome was a composite of COVID-19 death or hospice discharge within 30 days of discharge. The secondary outcome was intensive care unit (ICU) admission. The study included 426 patients: 16.7% died, 3.3% were discharged to hospice, and 20.0% were admitted to the ICU. Using multivariable analysis, race/ethnicity was not associated with the primary nor secondary outcome. In Model 4, age greater than 75 (odds ratio [OR]: 11.01; 95% confidence interval [CI]: 1.96-61.97) and renal disease (OR: 2.78; 95% CI: 1.31-5.90) were associated with higher odds of the composite primary outcome. Living in a "very-low-income area" (OR: 0.29; 95% CI: 0.12-0.71) and body mass index (BMI) 30-35 (OR: 0.24; 95% CI: 0.08-0.69) were associated with lower odds of the primary outcome. When controlling for demographics, SES, and comorbidities, race/ethnicity was not independently associated with the composite primary outcome. Very-low SES, as extrapolated from census-tract-level income data, was associated with lower odds of the composite primary outcome.

The mitochondrial inner membrane protein MPV17 prevents uracil accumulation in mitochondrial DNA.

Mitochondrial inner membrane protein MPV17 is a protein of unknown function that is associated with mitochondrial DNA (mtDNA)-depletion syndrome (MDS). MPV17 loss-of-function has been reported to result in tissue-specific nucleotide pool imbalances, which can occur in states of perturbed folate-mediated one-carbon metabolism (FOCM), but MPV17 has not been directly linked to FOCM. FOCM is a metabolic network that provides one-carbon units for the de novo synthesis of purine and thymidylate nucleotides (e.g. dTMP) for both nuclear DNA (nuDNA) and mtDNA replication. In this study, we investigated the impact of reduced MPV17 expression on markers of impaired FOCM in HeLa cells. Depressed MPV17 expression reduced mitochondrial folate levels by 43% and increased uracil levels, a marker of impaired dTMP synthesis, in mtDNA by 3-fold. The capacity of mitochondrial de novo and salvage pathway dTMP biosynthesis was unchanged by the reduced MPV17 expression, but the elevated levels of uracil in mtDNA suggested that other sources of mitochondrial dTMP are compromised in MPV17-deficient cells. These results indicate that MPV17 provides a third dTMP source, potentially by serving as a transporter that transfers dTMP from the cytosol to mitochondria to sustain mtDNA synthesis. We propose that MPV17 loss-of-function and related hepatocerebral MDS are linked to impaired FOCM in mitochondria by providing insufficient access to cytosolic dTMP pools and by severely reducing mitochondrial folate pools.

Onco-metabolism: defining the prognostic significance of obesity and diabetes in women with brain metastases from breast cancer.

PURPOSE: Metabolic dysregulation has been implicated as a molecular driver of breast cancer in preclinical studies, especially with respect to metastases. We hypothesized that abnormalities in patient metabolism, such as obesity and diabetes, may drive outcomes in breast cancer patients with brain metastases. METHODS: We retrospectively identified 84 consecutive patients with brain metastases from breast cancer treated with intracranial radiation therapy. Radiation was delivered as whole-brain radiation to a median dose of 3000 cGy or stereotactic radiosurgery to a median dose of 2100 cGy. Kaplan Meier curves were generated for overall survival (OS) data and Mantel-Cox regression was performed to detect differences in groups. RESULTS: At analysis, 81 survival events had occurred and the median OS for the entire cohort was 21.7 months. Despite similar modified graded prognostic assessments, resection rates, and receptor status, BMI ≥ 25 kg/m2 (n = 45) was associated with decreased median OS (13.7 vs. 30.6 months; p < 0.001) and median intracranial progression-free survival (PFS) (7.4 vs. 10.9 months; p = 0.04) compared to patients with BMI < 25 kg/m2 (n = 39). Similar trends were observed among all three types of breast cancer. Patients with diabetes (n = 17) had decreased median OS (11.8 vs. 26.2 months; p < 0.001) and median intracranial PFS (4.5 vs. 10.3 months; p = 0.001) compared to non-diabetics (n = 67). On multivariate analysis, both BMI ≥ 25 kg/m2 [HR 2.35 (1.39-3.98); p = 0.002] and diabetes [HR 2.77 (1.454-5.274); p = 0.002] were associated with increased mortality. CONCLUSIONS: Elevated BMI or diabetes may negatively impact both overall survival and local control in patients with brain metastases from breast cancer, highlighting the importance of the translational development of therapeutic metabolic interventions. Given its prognostic significance, BMI should be used as a stratification in future clinical trial design in this patient population.

Injectable, Guest-Host Assembled Polyethylenimine Hydrogel for siRNA Delivery.

While siRNA has tremendous potential for therapeutic applications, advancement is limited by poor delivery systems. Systemically, siRNAs are rapidly degraded, may have off-target silencing, and necessitate high working concentrations. To overcome this, we developed an injectable, guest-host assembled hydrogel between polyethylenimine (PEI) and polyethylene glycol (PEG) for local siRNA delivery. Guest-host modified polymers assembled with siRNAs to form polyplexes that had improved transfection and viability compared to PEI. At higher concentrations, these polymers assembled into shear-thinning hydrogels that rapidly self-healed. With siRNA encapsulation, the assemblies eroded as polyplexes which were active and transfected cells, observed by Cy3-siRNA uptake or GFP silencing in vitro. When injected into rat myocardium, the hydrogels localized polyplex release, observed by uptake of Cy5.5-siRNA and silencing of GFP for 1 week in a GFP-expressing rat. These results illustrate the potential for this system to be applied for therapeutic siRNA delivery, such as in cardiac pathologies.

External validation of the COVID-19 4C mortality score in an urban United States cohort.

BACKGROUND: Identifying patients at risk for mortality from COVID-19 is crucial to triage, clinical decision-making, and the allocation of scarce hospital resources. The 4C Mortality Score effectively predicts COVID-19 mortality, but it has not been validated in a United States (U.S.) population. The purpose of this study is to determine whether the 4C Mortality Score accurately predicts COVID-19 mortality in an urban U.S. adult inpatient population. METHODS: This retrospective cohort study included adult patients admitted to a single-center, tertiary care hospital (Philadelphia, PA) with a positive SARS-CoV-2 PCR from 3/01/2020 to 6/06/2020. Variables were extracted through a combination of automated export and manual chart review. The outcome of interest was mortality during hospital admission or within 30 days of discharge. RESULTS: This study included 426 patients; mean age was 64.4 years, 43.4% were female, and 54.5% self-identified as Black or African American. All-cause mortality was observed in 71 patients (16.7%). The area under the receiver operator characteristic curve of the 4C Mortality Score was 0.85 (95% confidence interval, 0.79-0.89). CONCLUSIONS: Clinicians may use the 4C Mortality Score in an urban, majority Black, U.S. inpatient population. The derivation and validation cohorts were treated in the pre-vaccine era so the 4C Score may over-predict mortality in current patient populations. With stubbornly high inpatient mortality rates, however, the 4C Score remains one of the best tools available to date to inform thoughtful triage and treatment allocation.

Development and Validation of a Web-Based Severe COVID-19 Risk Prediction Model.

BACKGROUND: Coronavirus disease 2019 (COVID-19) carries high morbidity and mortality globally. Identification of patients at risk for clinical deterioration upon presentation would aid in triaging, prognostication, and allocation of resources and experimental treatments. RESEARCH QUESTION: Can we develop and validate a web-based risk prediction model for identification of patients who may develop severe COVID-19, defined as intensive care unit (ICU) admission, mechanical ventilation, and/or death? METHODS: This retrospective cohort study reviewed 415 patients admitted to a large urban academic medical center and community hospitals. Covariates included demographic, clinical, and laboratory data. The independent association of predictors with severe COVID-19 was determined using multivariable logistic regression. A derivation cohort (n=311, 75%) was used to develop the prediction models. The models were tested by a validation cohort (n=104, 25%). RESULTS: The median age was 66 years (Interquartile range [IQR] 54-77) and the majority were male (55%) and non-White (65.8%). The 14-day severe COVID-19 rate was 39.3%; 31.7% required ICU, 24.6% mechanical ventilation, and 21.2% died. Machine learning algorithms and clinical judgment were used to improve model performance and clinical utility, resulting in the selection of eight predictors: age, sex, dyspnea, diabetes mellitus, troponin, C-reactive protein, D-dimer, and aspartate aminotransferase. The discriminative ability was excellent for both the severe COVID-19 (training area under the curve [AUC]=0.82, validation AUC=0.82) and mortality (training AUC= 0.85, validation AUC=0.81) models. These models were incorporated into a mobile-friendly website. CONCLUSIONS: This web-based risk prediction model can be used at the bedside for prediction of severe COVID-19 using data mostly available at the time of presentation.

Delivery of progenitor cells with injectable shear-thinning hydrogel maintains geometry and normalizes strain to stabilize cardiac function after ischemia.

OBJECTIVES: The ventricle undergoes adverse remodeling after myocardial infarction, resulting in abnormal biomechanics and decreased function. We hypothesize that tissue-engineered therapy could minimize postischemic remodeling through mechanical stress reduction and retention of tensile myocardial properties due to improved endothelial progenitor cell retention and intrinsic biomechanical properties of the hyaluronic acid shear-thinning gel. METHODS: Endothelial progenitor cells were harvested from adult Wistar rats and resuspended in shear-thinning gel. The constructs were injected at the border zone of ischemic rat myocardium in an acute model of myocardial infarction. Myocardial remodeling, tensile properties, and hemodynamic function were analyzed: control (phosphate-buffered saline), endothelial progenitor cells, shear-thinning gel, and shear-thinning gel + endothelial progenitor cells. Novel high-resolution, high-sensitivity ultrasound with speckle tracking allowed for global strain analysis. Uniaxial testing assessed tensile biomechanical properties. RESULTS: Shear-thinning gel + endothelial progenitor cell injection significantly increased engraftment and retention of the endothelial progenitor cells within the myocardium compared with endothelial progenitor cells alone. With the use of strain echocardiography, a significant improvement in left ventricular ejection fraction was noted in the shear-thinning gel + endothelial progenitor cell cohort compared with control (69.5% ± 10.8% vs 40.1% ± 4.6%, P = .04). A significant normalization of myocardial longitudinal displacement with subsequent stabilization of myocardial velocity with shear-thinning gel + endothelial progenitor cell therapy compared with control was also evident (0.84 + 0.3 cm/s vs 0.11 ± 0.01 cm/s, P = .03). A significantly positive and higher myocardial strain was observed in shear-thinning gel + endothelial progenitor cell (4.5% ± 0.45%) compared with shear-thinning gel (3.7% ± 0.24%), endothelial progenitor cell (3.5% ± 0.97%), and control (8.6% ± 0.3%, P = .05). A resultant reduction in dynamic stiffness was noted in the shear-thinning gel + endothelial progenitor cell cohort. CONCLUSIONS: This novel injectable shear-thinning hyaluronic acid hydrogel demonstrates stabilization of border zone myocardium with reduction in adverse myocardial remodeling and preservation of myocardial biomechanics. The cellular construct provides a normalization of strain measurements and reduces left ventricular dilatation, thus resulting in improvement of left ventricular function.

Sustained release of endothelial progenitor cell-derived extracellular vesicles from shear-thinning hydrogels improves angiogenesis and promotes function after myocardial infarction.

Aims: Previous studies have demonstrated improved cardiac function following myocardial infarction (MI) after administration of endothelial progenitor cells (EPCs) into ischaemic myocardium. A growing body of literature supports paracrine effectors, including extracellular vesicles (EVs), as the main mediators of the therapeutic benefits of EPCs. The direct use of paracrine factors is an attractive strategy that harnesses the effects of cell therapy without concerns of cell engraftment or viability. We aim to reproduce the beneficial effects of EPC treatment through delivery of EPC-derived EVs within a shear-thinning gel (STG) for precise localization and sustained delivery. Methods and results: EVs were harvested from EPCs isolated from adult male Rattus norvegicus (Wistar) rats and characterized by electron microscopy, nanoparticle tracking analysis (NTA), and mass spectrometry. EVs were incorporated into the STG and injected at the border zone in rat models of MI. Haemodynamic function, angiogenesis, and myocardial remodelling were analyzed in five groups: phosphate buffered saline (PBS) control, STG control, EVs in PBS, EVs in STG, and EPCs in STG. Electron microscopy and NTA of EVs showed uniform particles of 50-200 nm. EV content analysis revealed several key angiogenic mediators. EV uptake by endothelial cells was confirmed and followed by robust therapeutic angiogenesis. In vivo animal experiments demonstrated that delivery of EVs within the STG resulted in increased peri-infarct vascular proliferation, preservation of ventricular geometry, and improved haemodynamic function post-MI. Conclusions: EPC-derived EVs delivered into ischaemic myocardium via an injectable hydrogel enhanced peri-infarct angiogenesis and myocardial haemodynamics in a rat model of MI. The STG greatly increased therapeutic efficiency and efficacy of EV-mediated myocardial preservation.

In Vivo Anastomosis and Perfusion of a Three-Dimensionally-Printed Construct Containing Microchannel Networks.

The field of tissue engineering has advanced the development of increasingly biocompatible materials to mimic the extracellular matrix of vascularized tissue. However, a majority of studies instead rely on a multiday inosculation between engineered vessels and host vasculature rather than the direct connection of engineered microvascular networks with host vasculature. We have previously demonstrated that the rapid casting of three-dimensionally-printed (3D) sacrificial carbohydrate glass is an expeditious and a reliable method of creating scaffolds with 3D microvessel networks. Here, we describe a new surgical technique to directly connect host femoral arteries to patterned microvessel networks. Vessel networks were connected in vivo in a rat femoral artery graft model. We utilized laser Doppler imaging to monitor hind limb ischemia for several hours after implantation and thus measured the vascular patency of implants that were anastomosed to the femoral artery. This study may provide a method to overcome the challenge of rapid oxygen and nutrient delivery to engineered vascularized tissues implanted in vivo.

Transplantation of "high-risk" donor hearts: Implications for infection.

BACKGROUND: Heart transplantation is the gold-standard treatment for end-stage heart failure. Short- and long-term outcomes have been excellent, but the shortage of organs persists. The number of potential recipients who die while awaiting orthotopic heart transplantation increases yearly. In 2004, the label "high-risk donor" (HRD) was applied, by the United Network for Organ Sharing (UNOS), to any organ donor who met the Centers for Disease Control (CDC) criteria for behavior that put them at high risk of infection. Despite organ shortages, grafts from HRD CDCs are often declined, because of concerns regarding infection. We undertook this study to analyze our extensive experience with orthotopic heart transplantation of grafts from HRD CDCs, and to determine the short- and long-term outcomes associated with recipients of hearts from HRD CDCs, particularly transmission of infection. METHODS: We performed 367 heart transplantations at our center from September 2008 to September 2014, a timeframe during which the HRD CDC labeling had been implemented. Of the total number of orthotopic heart transplantations performed, 55 patients (15%) received organs from HRD CDCs that had known negative serology for human immunodeficiency virus (HIV), hepatitis B, and hepatitis C. We reviewed demographic, perioperative, and short- and long-term outcomes. The recipients of grafts from HRD CDCs were followed closely, with 3- and 12-month surveillance laboratory testing of viral load for HIV, for hepatitis B, and for hepatitis C core- and surface-antigen serology. RESULTS: All 55 patients (72.7% were men) underwent a successful transplantation procedure. One patient was excluded from follow-up analysis because he was re-transplanted within 4 days owing to the posttransplant finding of metastatic lung adenocarcinoma within the donor. Primary etiology of heart failure was ischemic in 18 of the patients. The most common blood type was O positive, in 20 patients (37.1%), followed by A positive, in 19 patients (35.2%). A total of 19 (35.2%) patients were supported with a mechanical assist device before the transplantation. The average allograft ischemic time was 173 ± 96 minutes. The median length of hospital stay was 19.5 days. A low incidence was observed of the postoperative complications of stroke (1.9%), dialysis (3.9%), and complete heart block (3.9%). Kaplan-Meier analysis demonstrated excellent survival, both short-term (1 year; 94%) and long-term (3 years; 80%). Allograft function was excellent at time of discharge with a left ejection fraction of 67.8% ± 7.3%. Only one patient (1.9%) was noted to have hepatitis C seroconversion at 105 days after receiving the transplant. After antiviral treatment, the patient has had undetectable viral loads to date. All other patients had undetectable plasma viral loads of HIV, hepatitis C, and hepatitis B, determined using rigorous testing. CONCLUSIONS: We present the only single-center series on recipients of heart transplants from HRD CDCs. This potential source of suitable donor organs is shown to lead to excellent survival, without an increased incidence of perioperative or postoperative complications. Furthermore, the risk of transmission of infection from donors in this subgroup seems to be minimal.

HeartMate II Left Ventricular Assist Device Geometry on Chest Radiograph Does Not Correlate with Risk of Pump Thrombosis.

Pump thrombosis (PT) is a common and potentially life-threatening complication among HeartMate II (HMII; Thoratec, Pleasanton, CA) patients. There have been efforts to correlate HMII geometry with higher risk of PT. The aim of this study was to test the validity of using HMII inflow cannula angle (ICA) and pump pocket depth (PPD) to predict PT. We performed a retrospective analysis of patients implanted with HMII left ventricular assist devices (LVADs) from January 2011 to March 2014 at our institution. Three blinded reviewers measured ICA and PPD from chest x-rays at postimplantation and most recent follow-up time points. The diagnosis of PT was visually confirmed upon device explantation by benchtop evaluation. HeartMate II was implanted in 90 patients. Sixteen (20%) patients experienced PT. There was no statistical difference between PT and non-PT patients in their initial ICAs (56.0° ± 10.1 vs. 54.6° ± 10.8, p = 0.63) and PPD (86.7 ± 24.9 mm vs. 81.1 ± 32.2 mm, p = 0.46). Prediction of PT using ICA and PPD by receiving operating characteristic was negative (area under curve (AUC) = 0.54 and 0.55, respectively). Changes in HMII geometry were measured over 112.5 (interquartile range = 34.3-337.3) days. A decrease in PPD was observed (p = 0.0001). Initial ICA was a significant predictor of future angle change and suggested a convergence toward the mean (55.4°) (analysis of variance p = 0.002). Pump thrombosis recurred in four (25%) patients. Postoperative ICA and PPD do not appear to predict PT in HMII patients in our experience. HeartMate II geometry changes over time secondary to remodeling with a decrease in PPD and a convergence toward the median in ICAs. Further investigation into the role of geometric ventricular assist device conformation postimplant may be warranted.

Injectable shear-thinning hydrogels used to deliver endothelial progenitor cells, enhance cell engraftment, and improve ischemic myocardium.

OBJECTIVES: The clinical translation of cell-based therapies for ischemic heart disease has been limited because of low cell retention (<1%) within, and poor targeting to, ischemic myocardium. To address these issues, we developed an injectable hyaluronic acid (HA) shear-thinning hydrogel (STG) and endothelial progenitor cell (EPC) construct (STG-EPC). The STG assembles as a result of interactions of adamantine- and ß-cyclodextrin-modified HA. It is shear-thinning to permit delivery via a syringe, and self-heals upon injection within the ischemic myocardium. This directed therapy to the ischemic myocardial border zone enables direct cell delivery to address adverse remodeling after myocardial infarction. We hypothesize that this system will enhance vasculogenesis to improve myocardial stabilization in the context of a clinically translatable therapy. METHODS: Endothelial progenitor cells (DiLDL(+) VEGFR2(+) CD34(+)) were harvested from adult male rats, cultured, and suspended in the STG. In vitro viability was quantified using a live-dead stain of EPCs. The STG-EPC constructs were injected at the border zone of ischemic rat myocardium after acute myocardial infarction (left anterior descending coronary artery ligation). The migration of the enhanced green fluorescent proteins from the construct to ischemic myocardium was analyzed using fluorescent microscopy. Vasculogenesis, myocardial remodeling, and hemodynamic function were analyzed in 4 groups: control (phosphate buffered saline injection); intramyocardial injection of EPCs alone; injection of the STG alone; and treatment with the STG-EPC construct. Hemodynamics and ventricular geometry were quantified using echocardiography and Doppler flow analysis. RESULTS: Endothelial progenitor cells demonstrated viability within the STG. A marked increase in EPC engraftment was observed 1-week postinjection within the treated myocardium with gel delivery, compared with EPC injection alone (17.2 ± 0.8 cells per high power field (HPF) vs 3.5 cells ± 1.3 cells per HPF, P = .0002). A statistically significant increase in vasculogenesis was noted with the STG-EPC construct (15.3 ± 5.8 vessels per HPF), compared with the control (P < .0001), EPC (P < .0001), and STG (P < .0001) groups. Statistically significant improvements in ventricular function, scar fraction, and geometry were noted after STG-EPC treatment compared with the control. CONCLUSIONS: A novel injectable shear-thinning HA hydrogel seeded with EPCs enhanced cell retention and vasculogenesis after delivery to ischemic myocardium. This therapy limited adverse myocardial remodeling while preserving contractility.