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Enzymes are being increasingly exploited for their potential as industrial biocatalysts. Establishing a portfolio of useful biocatalysts from large and diverse protein family is challenging and a systematic method for candidate selection promises to aid in this task. Moreover, accurate enzyme functional annotation can only be confidently guaranteed through experimental characterisation in the laboratory. The selection of catalytically diverse enzyme panels for experimental characterisation is also an important step for shedding light on the currently unannotated proteins in enzyme families. Current selection methods often lack efficiency and scalability, and are usually non-systematic. We present a novel algorithm for the automatic selection of subsets from enzyme families. A tabu search algorithm solving the maximum diversity problem for sequence identity was designed and implemented, and applied to three diverse enzyme families. We show that this approach automatically selects panels of enzymes that contain high richness and relative abundance of the known catalytic functions, and outperforms other methods such as k-medoids.
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Algoritmos , Proteínas , Proteínas/genética , Proteínas/metabolismo , CatálisisRESUMEN
OBJECTIVES: Coronavirus disease 2019 is associated with high mortality rates and multiple organ damage. There is increasing evidence that these patients are at risk for various cardiovascular insults; however, there are currently no guidelines for the diagnosis and management of such cardiovascular complications in patients with coronavirus disease 2019. We share data and recommendations from a multidisciplinary team to highlight our institution's clinical experiences and guidelines for managing cardiovascular complications of coronavirus disease 2019. DESIGN SETTING AND PATIENTS: This was a retrospective cohort study of patients admitted to one of six ICUs dedicated to the care of patients with coronavirus disease 2019 located in three hospitals within one academic medical center in Atlanta, Georgia. MEASUREMENTS/INTERVENTIONS: Chart review was conducted for sociodemographic, laboratory, and clinical data. Rates of specific cardiovascular complications were assessed, and data were analyzed using a chi-square or Wilcoxon rank-sum test for categorical and continuous variables. Additionally, certain cases are presented to demonstrate the sub committee's recommendations. MAIN RESULTS: Two-hundred eighty-eight patients were admitted to the ICU with coronavirus disease 2019. Of these, 86 died (29.9%), 242 (84.03%) had troponin elevation, 70 (24.31%) had dysrhythmias, four (1.39%) had ST-elevation myocardial infarction, eight (2.78%) developed cor pulmonale, and 190 (65.97%) with shock. There was increased mortality risk in patients with greater degrees of troponin elevation (p < 0.001) and with the development of arrhythmias (p < 0.001), cor pulmonale (p < 0.001), and shock (p < 0.001). CONCLUSIONS: While there are guidelines for the diagnosis and management of pulmonary complications of coronavirus disease 2019, there needs to be more information regarding the management of cardiovascular complications as well. These recommendations garnered from the coronavirus disease 2019 cardiology subcommittee from our institution will add to the existing knowledge of these potential cardiovascular insults as well as highlight suggestions for the diagnosis and management of the range of cardiovascular complications of coronavirus disease 2019. Additionally, with the spread of coronavirus disease 2019, our case-based recommendations provide a bedside resource for providers newly caring for patients with coronavirus disease 2019.
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Background "Financial toxicity" is a concern for patients, but little is known about how patients consider out-of-pocket cost in decisions. Sacubitril-valsartan provides a contemporary scenario to understand financial toxicity. It is guideline recommended for heart failure with reduced ejection fraction, yet out-of-pocket costs can be considerable. Methods and Results Structured interviews were conducted with 49 patients with heart failure with reduced ejection fraction at heart failure clinics and inpatient services. Patient opinions of the drug and its value were solicited after description of benefits using graphical displays. Descriptive quantitative analysis of closed-ended responses was conducted, and qualitative descriptive analysis of text data was performed. Of participants, 92% (45/49) said that they would definitely or probably switch to sacubitril-valsartan if their physician recommended it and out-of-pocket cost was $5 more per month than their current medication. Only 43% (21/49) would do so if out-of-pocket cost was $100 more per month ( P<0.001). At least 40% across all income categories would be unlikely to take sacubitril-valsartan at $100 more per month. Participants exhibited heterogeneous approaches to cost in decision making and varied on their use and interpretation of probabilistic information. Few (20%) participants stated physicians had initiated a conversation about cost in the past year. Conclusions Out-of-pocket cost variation reflective of contemporary cost sharing substantially influenced stated willingness to take sacubitril-valsartan, a guideline-recommended therapy with mortality benefit. These findings suggest a need for cost transparency to promote shared decision making. They also demonstrate the complexity of cost discussion and need to study how to incorporate out-of-pocket cost into clinical decisions.
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Aminobutiratos/economía , Toma de Decisiones Conjunta , Costos de los Medicamentos , Gastos en Salud/estadística & datos numéricos , Insuficiencia Cardíaca/tratamiento farmacológico , Tetrazoles/economía , Adulto , Anciano , Aminobutiratos/uso terapéutico , Compuestos de Bifenilo , Análisis Costo-Beneficio , Estudios Transversales , Combinación de Medicamentos , Femenino , Insuficiencia Cardíaca/economía , Humanos , Masculino , Persona de Mediana Edad , Años de Vida Ajustados por Calidad de Vida , Tetrazoles/uso terapéutico , Estados Unidos , ValsartánRESUMEN
OBJECTIVES: The aim of this study was to prospectively evaluate the impact of blood pressure management on stroke rates in patients receiving the HeartWare HVAD System. BACKGROUND: The ENDURANCE trial demonstrated noninferiority of the HeartWare HVAD System versus control (HeartMate II) in patients with advanced heart failure ineligible for heart transplantation. However, stroke was more common in HVAD subjects. Post hoc analyses demonstrated increased mean arterial blood pressure as a significant independent risk factor for stroke. METHODS: The ENDURANCE Supplemental Trial was a prospective, multicenter evaluation of 465 patients with advanced heart failure ineligible for transplantation, randomized 2:1 to HVAD (n = 308) or control (n = 157). The primary endpoint was the 12-month incidence of transient ischemic attack or stroke with residual deficit 24 weeks post-event. Secondary endpoints included the composite of freedom from death, disabling stroke, and need for device replacement or urgent transplantation, as well as comparisons of stroke or transient ischemic attack rates in HVAD cohorts in ENDURANCE Supplemental and ENDURANCE. RESULTS: The enhanced blood pressure protocol significantly reduced mean arterial blood pressure. The primary endpoint was not achieved (14.7% with HVAD vs. 12.1% with control, noninferiority [margin 6%] p = 0.14). However, the secondary composite endpoint demonstrated superiority of HVAD (76.1%) versus control (66.9%) (p = 0.04). The incidence of stroke in HVAD subjects was reduced 24.2% in ENDURANCE Supplemental compared with ENDURANCE (p = 0.10), and hemorrhagic cerebrovascular accident was reduced by 50.5% (p = 0.02). CONCLUSIONS: The ENDURANCE Supplemental Trial failed to demonstrate noninferiority of HVAD versus control regarding the pre-specified primary endpoint. However, the trial confirmed that BP management is associated with reduced stroke rates in HVAD subjects. HVAD subjects, relative to control subjects, more commonly achieved the composite endpoint (freedom from death, disabling stroke, and device replacement or urgent transplantation). (A Clinical Trial to Evaluate the HeartWare™ Ventricular Assist System [ENDURANCE SUPPLEMENTAL TRIAL] [DT2]; NCT01966458).
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Antihipertensivos/uso terapéutico , Insuficiencia Cardíaca/terapia , Corazón Auxiliar , Hipertensión/tratamiento farmacológico , Ataque Isquémico Transitorio/epidemiología , Accidente Cerebrovascular/epidemiología , Anciano , Anticoagulantes/uso terapéutico , Presión Arterial , Monitoreo Ambulatorio de la Presión Arterial , Estudios de Equivalencia como Asunto , Femenino , Insuficiencia Cardíaca/epidemiología , Humanos , Hipertensión/epidemiología , Masculino , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/uso terapéutico , Estudios ProspectivosRESUMEN
OBJECTIVES: This study sought to estimate the rate of progression to Stage D heart failure (HF) among outpatients with Stage C HF and to identify risk factors for progression. BACKGROUND: The pool of patients who may be candidates for advanced HF therapies is growing. METHODS: We estimated 3-year progression to clinically determined Stage D HF and competing mortality among 964 outpatients with Stage C heart failure with reduced ejection fraction (HFrEF), where ejection fraction is ≤40%. RESULTS: The mean age of patients was 62 ± 15 years; 35% were women; 47% were white; 46% were black, and 7% were of other races; median baseline ejection fraction was 28% (25th to 75th percentile: 20% to 35%); and 47% had ischemic heart disease. After 3.0 years (25th to 75th percentile: 1.7 to 3.2 years), 112 patients progressed to Stage D (3-year incidence: 12.2%; 95% confidence interval [CI]: 10.2% to 14.6%; annualized: 4.5%; 95% CI: 3.8% to 5.5%), and 116 patients died before progression (3-year competing mortality: 12.9%; annualized: 4.7%; 95% CI: 3.9% to 5.6%). By 3 years, 25.1% of patients (95% CI: 22.2% to 28.1%) had either progressed to Stage D or died (annualized: 9.2%; 95% CI: 8.1% to 10.5%). Annualized progression rates were higher in black versus white patients (6.3% vs. 2.7%, respectively; p < 0.001), nonischemic versus ischemic patients (6.1% vs. 2.9%, respectively; p < 0.001), and in New York Heart Association functional class III to IV versus I to II patients (7.5% vs. 1.9%, respectively; p < 0.001) but were similar for men and women (4.7% vs. 4.2%, respectively; p = 0.53). Lower ejection fraction and blood pressure, renal and hepatic dysfunction, and chronic lung disease rates were additional predictors of progression. Predictors of competing mortality were different from those of disease progression. CONCLUSIONS: Among patients with Stage C HFrEF receiving care in a referral center, 4.5% progressed to Stage D HF each year, with earlier progression among black and nonischemic patients. These findings have implications for healthcare planning and resource allocation for these patients.
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Progresión de la Enfermedad , Insuficiencia Cardíaca/terapia , Atención Ambulatoria/estadística & datos numéricos , Terapia de Resincronización Cardíaca/estadística & datos numéricos , Cardiotónicos/uso terapéutico , Femenino , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/fisiopatología , Corazón Auxiliar , Humanos , Masculino , Persona de Mediana Edad , Volumen Sistólico/fisiologíaRESUMEN
BACKGROUND: Trachoma is a blinding disease caused by conjunctival infection with Chlamydia trachomatis (Ct). Mass drug administration (MDA) for trachoma control is administered based on the population prevalence of the clinical sign of trachomatis inflammation - follicular (TF). However, the prevalence of TF is often much higher than the prevalence of Ct infection. The addition of a clinical sign specific for current ocular Ct infection to TF could save resources by preventing unnecessary additional rounds of MDA. METHODS: Study participants were aged between 1-9 years and resided on 7 islands of the Bijagos Archipelago, Guinea Bissau. Clinical grades for trachoma and corneal pannus and ocular swab samples were taken from 80 children with TF and from 81 matched controls without clinical evidence of trachoma. Ct infection testing was performed using droplet digital PCR. RESULTS: New pannus was significantly associated with Ct infection after adjustment for TF (P = 0.009, OR = 3.65 (1.4-9.8)). Amongst individuals with TF, individuals with new pannus had significantly more Ct infection than individuals with none or old pannus (75.0% vs 45.5%, Chi(2) P = 0.01). TF and new pannus together provide a highly specific (91.7%), but a poorly sensitive (51.9%) clinical diagnostic test for Ct infection. CONCLUSIONS: As we move towards trachoma elimination it may be desirable to use a combined clinical sign (new pannus in addition to TF) that is highly specific for current ocular Ct infection. This would allow national health systems to obtain a more accurate estimate of Ct population prevalence to inform further need for MDA without the expense of Ct molecular diagnostics, which are currently unaffordable in programmatic contexts.
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Antibacterianos/uso terapéutico , Infecciones por Chlamydia/diagnóstico , Chlamydia trachomatis/aislamiento & purificación , Tracoma/diagnóstico , Animales , Profilaxis Antibiótica , Niño , Preescolar , Infecciones por Chlamydia/tratamiento farmacológico , Infecciones por Chlamydia/prevención & control , Conjuntiva/microbiología , Ojo/microbiología , Femenino , Guinea Bissau/epidemiología , Humanos , Lactante , Inflamación , Masculino , Prevalencia , Tracoma/tratamiento farmacológico , Tracoma/prevención & controlRESUMEN
BACKGROUND: Current-generation left ventricular assist devices provide circulatory support that is minimally or entirely nonpulsatile and are associated with marked increases in muscle sympathetic nerve activity (MSNA), likely through a baroreceptor-mediated pathway. We sought to determine whether the restoration of pulsatile flow through modulations in pump speed would reduce MSNA through the arterial baroreceptor reflex. METHODS AND RESULTS: Ten men and 3 women (54 ± 14 years) with Heartmate II continuous-flow left ventricular assist devices underwent hemodynamic and sympathetic neural assessment. Beat-to-beat blood pressure, carotid ultrasonography at the level of the arterial baroreceptors, and MSNA via microneurography were continuously recorded to determine steady-state responses to step changes (200-400 revolutions per minute) in continuous-flow left ventricular assist device pump speed from a maximum of 10,480 ± 315 revolutions per minute to a minimum of 8500 ± 380 revolutions per minute. Reductions in pump speed led to increases in pulse pressure (high versus low speed: 17 ± 7 versus 26 ± 12 mm Hg; P<0.01), distension of the carotid artery, and carotid arterial wall tension (P<0.05 for all measures). In addition, MSNA was reduced (high versus low speed: 41 ± 15 versus 33 ± 16 bursts per minute; P<0.01) despite a reduction in mean arterial pressure and was inversely related to pulse pressure (P=0.037). CONCLUSIONS: Among subjects with continuous-flow left ventricular assist devices, the restoration of pulsatile flow through modulations in pump speed leads to increased distortion of the arterial baroreceptors with a subsequent decline in MSNA. Additional study is needed to determine whether reduction of MSNA in this setting leads to improved outcomes.
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Barorreflejo/fisiología , Corazón Auxiliar , Hemodinámica/fisiología , Presorreceptores/fisiología , Flujo Pulsátil/fisiología , Función Ventricular Izquierda/fisiología , Adulto , Anciano , Femenino , Corazón Auxiliar/tendencias , Humanos , Masculino , Persona de Mediana Edad , Sistema Nervioso Simpático/fisiologíaRESUMEN
BACKGROUND: Peripartum cardiomyopathy (PPCM) remains a major cause of maternal morbidity and mortality. OBJECTIVES: This study sought to prospectively evaluate recovery of the left ventricular ejection fraction (LVEF) and clinical outcomes in the multicenter IPAC (Investigations of Pregnancy Associated Cardiomyopathy) study. METHODS: We enrolled and followed 100 women with PPCM through 1 year post-partum. The LVEF was assessed by echocardiography at baseline and at 2, 6, and 12 months post-partum. Survival free from major cardiovascular events (death, transplantation, or left ventricular [LV] assist device) was determined. Predictors of outcome, particularly race, parameters of LV dysfunction (LVEF), and remodeling (left ventricular end-diastolic diameter [LVEDD]) at presentation, were assessed by univariate and multivariate analyses. RESULTS: The cohort was 30% black, 65% white, 5% other; the mean patient age was 30 ± 6 years; and 88% were receiving beta-blockers and 81% angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. The LVEF at study entry was 0.35 ± 0.10, 0.51 ± 0.11 at 6 months, and 0.53 ± 0.10 at 12 months. By 1 year, 13% had experienced major events or had persistent severe cardiomyopathy with an LVEF <0.35, and 72% achieved an LVEF ≥0.50. An initial LVEF <0.30 (p = 0.001), an LVEDD ≥6.0 cm (p < 0.001), black race (p = 0.001), and presentation after 6 weeks post-partum (p = 0.02) were associated with a lower LVEF at 12 months. No subjects with both a baseline LVEF <0.30 and an LVEDD ≥6.0 cm recovered by 1 year post-partum, whereas 91% with both a baseline LVEF ≥0.30 and an LVEDD <6.0 cm recovered (p < 0.00001). CONCLUSIONS: In a prospective cohort with PPCM, most women recovered; however, 13% had major events or persistent severe cardiomyopathy. Black women had more LV dysfunction at presentation and at 6 and 12 months post-partum. Severe LV dysfunction and greater remodeling at study entry were associated with less recovery. (Investigations of Pregnancy Associated Cardiomyopathy [IPAC]; NCT01085955).
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Cardiomiopatías/fisiopatología , Complicaciones Cardiovasculares del Embarazo/fisiopatología , Adolescente , Adulto , Cardiomiopatías/epidemiología , Femenino , Humanos , Periodo Posparto , Embarazo , Complicaciones Cardiovasculares del Embarazo/epidemiología , Estudios Prospectivos , Grupos Raciales , Volumen Sistólico , Estados Unidos/epidemiología , Adulto JovenRESUMEN
BACKGROUND: Several clinical prediction schemes for right ventricular failure (RVF) risk after left ventricular assist device (LVAD) implantation have been developed in both the pulsatile- and continuous-flow LVAD eras. The performance of these models has not been evaluated systematically in a continuous-flow LVAD cohort. METHODS: We evaluated 6 clinical RVF prediction models (Michigan, Penn, Utah, Kormos et al, CRITT, Pittsburgh Decision Tree) in 116 patients (age 51 ± 13 years; 41.4% white and 56.0% black; 66.4% men; 56.0% bridge to transplant, 37.1% destination therapy, 17.4% bridge to decision) who received a continuous-flow LVAD (HeartMate II: 79 patients, HeartWare: 37 patients) between 2008 and 2013. RESULTS: Overall, 37 patients (31.9%) developed RVF, defined: as pulmonary vasodilator use for ≥48 hours or inotrope use for ≥14 days post-operatively; re-institution of inotropes; multi-organ failure due to RVF; or need for mechanical RV support. Median (Quartile 1 to Quartile 3) time to initial discontinuation of inotropes was 6 (range 4 to 8) days. Among scores, the Michigan score reached significance for RVF prediction but discrimination was modest (C = 0.62 [95% CI 0.52 to 0.72], p = 0.021; positive predictive value [PPV] 60.0%; negative predictive value [NPV] 75.8%), followed by CRITT (C = 0.60 [95% CI 0.50 to 0.71], p = 0.059; PPV 40.5%; NPV 72.2%). Other models did not significantly discriminate RVF. The newer, INTERMACS 3.0 definition for RVF, which includes inotropic support beyond 7 days, was reached by 57 patients (49.1%). The Kormos model performed best with this definition (C = 0.62 [95% CI 0.54 to 0.71], p = 0.005; PPV 64.3%; NPV 59.5%), followed by Penn (C = 0.61), Michigan (C = 0.60) and CRITT (C = 0.60), but overall score performance was modest. CONCLUSION: Current schemes for post-LVAD RVF risk prediction perform only modestly when applied to external populations.
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Insuficiencia Cardíaca/diagnóstico , Corazón Auxiliar , Complicaciones Posoperatorias/diagnóstico , Disfunción Ventricular Derecha/diagnóstico , Femenino , Predicción , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Medición de RiesgoRESUMEN
The past decade has seen remarkable gains for outcomes in peripartum cardiomyopathy (PPCM), one of the leading causes of maternal mortality and morbidity in the USA and many other countries, including the high-incidence areas of Haiti and South Africa. This review article emphasizes the importance of continuing the process of increasing awareness of PPCM and presents details of this evolving picture, including important discoveries that point the way to full recovery for almost all PPCM subjects. In addition, new interventions will be highlighted, which may facilitate recovery. Numerous studies have demonstrated that when the diagnosis of PPCM is made with LVEF > 0.30, the probability is that recovery to LVEF ≥ 0.50 will occur in the overwhelming majority of subjects. PPCM patients diagnosed with severely depressed systolic function (LVEF < 0.30) and a remodeled left ventricle with greater dilatation (LVEDd ≥ 60mm) are least likely to reach the outcome recovery goals. These are the patients with the greatest need for newer interventional strategies.
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Cardiomiopatías/fisiopatología , Periodo Periparto/fisiología , Complicaciones Cardiovasculares del Embarazo/fisiopatología , Femenino , Humanos , Embarazo , Disfunción Ventricular Izquierda/fisiopatologíaRESUMEN
BACKGROUND: Insertion of a left ventricular assist device (LVAD) is an accepted therapy for advanced heart failure patients. However, the effects on end-organ perfusion, including cerebral autoregulation, are unclear in the presence of reduced pulsatility. Therefore, the objective of this study was to determine whether cerebral autoregulation is impaired in patients with continuous-flow (CF) LVADs. METHODS: Dynamic cerebral autoregulation was assessed in both time-domain (autoregulatory index) and frequency-domain (transfer function analysis) analyses in 9 CF-LVAD subjects, 5 pulsatile LVAD subjects and 10 healthy controls, by evaluating mean arterial pressure (MAP) and cerebral blood flow velocity (CBFV) during a sit-stand maneuver at 0.05 Hz (10-second sit, 10-second stand). The autoregulatory index was calculated as the percent change in mean CBFV per mm Hg change in MAP. RESULTS: The magnitude of oscillation in MAP and CBFV was greater in subjects with pulsatile LVADs than either CF-LVADs or healthy controls (p = 0.065 for MAP, p = 0.004 for CBFV). The autoregulatory index and transfer function gain were similar among groups, indicating that dynamic cerebral autoregulation is preserved among patients with CF-LVADs. CONCLUSIONS: Cerebral blood flow in patients with CF-LVADs is comparable to that of healthy controls across a range of blood pressures. Patients with pulsatile devices have greater oscillations in MAP and CBFV. However, dynamic cerebral autoregulation is preserved among subjects with either type of device. Thus, the reduction in pulsatility afforded by CF-LVADs does not impair normal autoregulatory processes.
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Circulación Cerebrovascular/fisiología , Insuficiencia Cardíaca/terapia , Corazón Auxiliar , Flujo Pulsátil/fisiología , Disfunción Ventricular Izquierda/terapia , Adulto , Anciano , Presión Sanguínea/fisiología , Gasto Cardíaco/fisiología , Estudios de Casos y Controles , Femenino , Insuficiencia Cardíaca/fisiopatología , Hemodinámica/fisiología , Homeostasis/fisiología , Humanos , Masculino , Persona de Mediana Edad , Flujo Sanguíneo Regional/fisiología , Disfunción Ventricular Izquierda/fisiopatologíaRESUMEN
BACKGROUND: Some cardiac transplant programs may upgrade listed patients to United Network for Organ Sharing (UNOS) 1A-status during the holidays. Whether more transplants actually occur during holidays is unknown. METHODS: We assessed rates of single-organ heart transplantation from 2001 to 2010 for recipients age ≥18 yr using the UNOS database. Patients were stratified by transplantation during holiday (±3 d, n = 2375) and non-holiday periods (n = 16 112). Holidays included Easter/Spring break, Memorial Day, July 4th, Labor Day, Thanksgiving, and Christmas/New Years (winter holidays). Secondary analysis assessing transplant rates across seasons was also completed. RESULTS: Donor and recipient characteristics were similar between groups. Compared with non-holidays, July 4th had higher transplant rates (5.69 vs. 5.09 transplants/d, p = 0.03) while the winter holiday had lower transplant rates (4.50 vs. 5.09 transplants/d, p < 0.01). There was a trend toward lower transplant rates for all holidays compared with non-holidays (p = 0.06). Transplant rates were significantly different across seasons with greater rates in spring and summer (p < 0.01). CONCLUSION: Heart transplant rates were higher during the July 4th and lower during the winter holidays. Although there was a higher likelihood of transplantation during the spring and summer seasons, upgrading patients to 1A status during most holidays may not improve their chances for transplantation.
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Trasplante de Corazón/estadística & datos numéricos , Vacaciones y Feriados/estadística & datos numéricos , Estaciones del Año , Obtención de Tejidos y Órganos , Adulto , Femenino , Estudios de Seguimiento , Trasplante de Corazón/mortalidad , Humanos , Masculino , Selección de Paciente , Pronóstico , Sistema de Registros , Tasa de Supervivencia , Estados UnidosRESUMEN
BACKGROUND: A noninvasive biomarker that could accurately diagnose acute rejection (AR) in heart transplant recipients could obviate the need for surveillance endomyocardial biopsies. We assessed the performance metrics of a novel high-sensitivity cardiac troponin I (cTnI) assay for this purpose. METHODS AND RESULTS: Stored serum samples were retrospectively matched to endomyocardial biopsies in 98 cardiac transplant recipients, who survived ≥3 months after transplant. AR was defined as International Society for Heart and Lung Transplantation grade 2R or higher cellular rejection, acellular rejection, or allograft dysfunction of uncertain pathogenesis, leading to treatment for presumed rejection. cTnI was measured with a high-sensitivity assay (Abbott Diagnostics, Abbott Park, IL). Cross-sectional analyses determined the association of cTnI concentrations with rejection and International Society for Heart and Lung Transplantation grade and the performance metrics of cTnI for the detection of AR. Among 98 subjects, 37% had ≥1 rejection episode. cTnI was measured in 418 serum samples, including 35 paired to a rejection episode. cTnI concentrations were significantly higher in rejection versus nonrejection samples (median, 57.1 versus 10.2 ng/L; P<0.0001) and increased in a graded manner with higher biopsy scores (P(trend)<0.0001). The c-statistic to discriminate AR was 0.82 (95% confidence interval, 0.76-0.88). Using a cut point of 15 ng/L, sensitivity was 94%, specificity 60%, positive predictive value 18%, and negative predictive value 99%. CONCLUSIONS: A high-sensitivity cTnI assay seems useful to rule out AR in cardiac transplant recipients. If validated in prospective studies, a strategy of serial monitoring with a high-sensitivity cTnI assay may offer a low-cost noninvasive strategy for rejection surveillance.
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Rechazo de Injerto/diagnóstico , Trasplante de Corazón , Tamizaje Masivo/métodos , Troponina I/sangre , Adulto , Anciano , Biomarcadores/sangre , Biopsia , Estudios de Cohortes , Estudios Transversales , Femenino , Rechazo de Injerto/sangre , Rechazo de Injerto/patología , Humanos , Masculino , Persona de Mediana Edad , Miocardio/patología , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
OBJECTIVES: This study sought to examine the frequency and hemodynamic correlates of shortness of breath when bending forward, a symptom we have termed "bendopnea." BACKGROUND: Many heart failure patients describe bendopnea such as when putting on their shoes. This symptom has not previously been characterized. METHODS: We conducted a prospective study of 102 subjects with systolic heart failure referred for right-heart catheterization. Time to onset of bendopnea was measured prior to catheterization. Forty-six subjects also underwent hemodynamic assessment when sitting and bending. Hemodynamic profiles were assigned on the basis of whether pulmonary capillary wedge pressure (PCWP) was ≥ 22 mm Hg and cardiac index (CI) was ≤ 2.2 l/min/m(2). RESULTS: Bendopnea was present in 29 of 102 (28%) subjects with median (25th, 75th percentiles) time to onset of 8 (7, 11) seconds. Subjects with bendopnea had higher supine right atrial pressure (RAP) (p = 0.001) and PCWP (p = 0.0004) than those without bendopnea but similar CI (p = 0.2). RAP and PCWP increased comparably in subjects with and without bendopnea when bending, but CI did not change. In those with, versus without, bendopnea, there was more than a 3-fold higher frequency of a supine hemodynamic profile consisting of elevated PCWP with low CI (55% vs. 16%, respectively, p < 0.001) but no association with a profile of elevated PCWP with normal CI (p = 0.95). CONCLUSIONS: Bendopnea is mediated via a further increase in filling pressures during bending when filling pressures are already high, particularly if CI is reduced. Awareness of bendopnea should improve noninvasive assessment of hemodynamics in subjects with heart failure.
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Disnea/etiología , Insuficiencia Cardíaca/complicaciones , Postura/fisiología , Anciano , Disnea/fisiopatología , Femenino , Insuficiencia Cardíaca/fisiopatología , Hemodinámica/fisiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Posición Supina/fisiologíaRESUMEN
Sirolimus is used in cardiac transplant recipients to prevent rejection, progression of cardiac allograft vasculopathy, and renal dysfunction. However, sirolimus has many potential side effects and its tolerability when used outside of clinical trials is not well established. We describe a decade of experience with sirolimus in cardiac transplant recipients at our institution. We retrospectively reviewed records of all adult cardiac transplant recipients living between September 1999 and February 2010 (n = 329) and identified 67 patients (20%) who received sirolimus. The indications for sirolimus were cardiac allograft vasculopathy (67%), renal dysfunction (25%), rejection (4%), and intolerability of tacrolimus (3%). One-third of patients discontinued sirolimus at a median (25th, 75th percentiles) of 0.9 (0.2, 1.6) yr of duration. Over 70% of subjects experienced an adverse event attributed to sirolimus. Adverse events were associated with higher average sirolimus levels (9.1 ng/mL vs. 7.1 ng/mL, p = 0.004). We conclude that sirolimus is frequently used in cardiac transplant recipients (20%) and commonly causes side effects, often necessitating discontinuation. Higher average sirolimus levels were associated with adverse events, suggesting that tolerability may improve if levels are maintained within the lower end of the current therapeutic range; however, the improvement in tolerability would need to be balanced with the potential for decreased efficacy.
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Rechazo de Injerto/prevención & control , Cardiopatías/cirugía , Trasplante de Corazón , Inmunosupresores/uso terapéutico , Sirolimus/uso terapéutico , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Tasa de SupervivenciaRESUMEN
BACKGROUND: Although right atrial pressure (RAP) and pulmonary capillary wedge pressure (PCWP) are correlated in heart failure, in a sizeable minority of patients, the RAP and PCWP are not tightly coupled. The basis of this variability in the RAP/PCWP ratio, and whether it conveys prognostic value, is not known. METHODS AND RESULTS: We analyzed the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial database. Baseline characteristics, including echocardiographic assessment of right ventricular (RV) structure and function, and invasively measured hemodynamic parameters, were compared among tertiles of the RAP/PCWP ratio. Multivariable Cox proportional hazard models assessed the association of RAP/PCWP ratio with the primary ESCAPE outcome (6-month death or hospitalization [days]) adjusting for systolic blood pressure, blood urea nitrogen, 6-minute walk distance, and PCWP. The RAP/PCWP tertiles were 0.27 to 0.4 (tertile 1); 0.41 to 0.615 (tertile 2), and 0.62 to 1.21 (tertile 3). Increasing RAP/PCWP was associated with increasing median right atrial area (23, 26, 29 cm2, respectively; P<0.005), RV area in diastole (21, 27, 27 cm2, respectively; P<0.005), and pulmonary vascular resistance (2.4, 2.9, 3.6 woods units, respectively; P=0.003), and lower RV stroke work index (8.6, 8.4, 5.5 g·m/m2 per beat, respectively; P<0.001). RAP/PCWP ratio was associated with death or hospitalization within 6 months (hazard ratio, 1.16 [1, 1.4]; P<0.05). CONCLUSIONS: Increased RAP/PCWP ratio was associated with higher pulmonary vascular resistance, reduced RV function (manifest as a larger right atrium and ventricle and lower RV stroke work index), and an increased risk of adverse outcomes in patients with advanced heart failure.
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Insuficiencia Cardíaca/fisiopatología , Hemodinámica , Función Ventricular Izquierda , Función Ventricular Derecha , Anciano , Función del Atrio Derecho , Presión Atrial , Canadá/epidemiología , Cateterismo Cardíaco , Distribución de Chi-Cuadrado , Ecocardiografía , Prueba de Esfuerzo , Femenino , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/mortalidad , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Análisis Multivariante , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Arteria Pulmonar/fisiopatología , Presión Esfenoidal Pulmonar , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Estados Unidos/epidemiología , Resistencia VascularRESUMEN
INTRODUCTION: The scaphoid bone is the most commonly fractured carpal bone. MRI is now recognised to be more sensitive and specific than serial plain films in the diagnosis of occult scaphoid fracture. What is not known is whether it is safe to discharge, without follow-up, those with a normal limited extremity MRI. The primary objective of this study was to determine whether a normal limited scaphoid MRI safely excludes clinically significant injury. The secondary objectives were to determine morbidity and patient experiences of those without fracture on MRI. METHODS: This is a cohort study with retrospective case note review and a written follow-up questionnaire conducted in a South of England emergency department soft tissue review clinic. RESULTS: 214 limited extremity MRIs were performed between January 2006 and July 2008 for suspected scaphoid injury. 152 participants were included in the study. 122 (80%) MRIs showed no fracture. In 72 (47%), there were no traumatic findings. The most significant finding in 33 (22%) was bony bruising and joint oedema in 17 (11%). One (0.9%) clinically important injury was missed. There was significant morbidity in those with normal MRIs. Worst-case scenario analysis shows that at least 12.5% of patients with a normal MRI still had symptoms and 14% still had abnormal function a year or more after injury. DISCUSSION: This study shows that limited extremity MRI can safely exclude clinically important injury. Significant symptoms do persist, however, for many patients with a normal MRI.
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Servicio de Urgencia en Hospital , Fracturas Óseas/diagnóstico , Imagen por Resonancia Magnética/métodos , Hueso Escafoides/lesiones , Adulto , Diagnóstico Diferencial , Inglaterra , Femenino , Humanos , Masculino , Estudios Retrospectivos , Encuestas y CuestionariosRESUMEN
AIMS: Left atrial (LA) structural and functional abnormalities may be subclinical phenotypes, which identify individuals at increased risk of adverse outcomes. METHODS AND RESULTS: Maximum LA volume (LAmax) and LA emptying fraction (LAEF) were measured via cardiac magnetic resonance imaging in 1802 participants in the Dallas Heart Study. The associations of LAEF and LAmax indexed to body surface area (LAmax/BSA) with traditional risk factors, natriuretic peptide levels, and left ventricular (LV) structure [end-diastolic volume (EDV) and concentricity(0.67) (mass/EDV(0.67))] and function (ejection fraction) were assessed using linear regression analysis. The incremental prognostic value of LAmax/BSA and LAEF beyond traditional risk factors, LV ejection fraction, and LV mass was assessed using the Cox proportional-hazards model. Both increasing LAmax/BSA and decreasing LAEF were associated with hypertension and natriuretic peptide levels (P < 0.05 for all). In multivariable analysis, LAmax/BSA was most strongly associated with LV end-diastolic volume/BSA, while LAEF was strongly associated with LV ejection fraction and concentricity(0.67). During a median follow-up period of 8.1 years, there were 81 total deaths. Decreasing LAEF [hazard ratio (HR) per 1 standard deviation (SD) (8.0%): 1.56 (1.32-1.87)] but not increasing LAmax/BSA [HR per 1 SD (8.6 mL/m(2)): 1.14 (0.97-1.34)] was independently associated with mortality. Furthermore, the addition of LAEF to a model adjusting Framingham risk score, diabetes, race, LV mass, and ejection fraction improved the c-statistic (c-statistics: 0.78 vs. 0.77; P < 0.05, respectively), whereas the addition of LAmax/BSA did not (c-statistics: 0.76, P = 0.20). CONCLUSION: In the general population, both LAmax/BSA and LAEF are important subclinical phenotypes but LAEF is superior and incremental to LAmax/BSA.