Drug levels after sirolimus initiation and short-term outcomes in ambulatory heart transplantation recipients.

INTRODUCTION: We evaluated the effect of relative changes in combined tacrolimus and sirolimus (drug) levels, following sirolimus initiation, on outcomes in ambulatory heart transplantation (HTx) recipients. METHODS: We performed a retrospective analysis of HTx recipients who received tacrolimus, followed by sirolimus initiation, any time after HTx. We calculated the relative change in combined drug levels 1-month post-sirolimus initiation, relative to tacrolimus levels pre-initiation, and categorized patients into decreased (≥15% decrease), stable (<15% decrease to <15% increase), or increased (≥15% increase) groups. We compared, across the three groups, changes in post-initiation estimated glomerular filtration rate (eGFR) and left ventricular ejection fraction (LVEF) using one-way ANOVA and Sidák's post-hoc analysis, as well as the individual and composite outcomes of new donor specific antibodies (DSA), acute cellular rejection (ACR), and all-cause mortality using Fisher's exact test. RESULTS: Amongst 99 HTx recipients included, the median age was 53 years, time to sirolimus initiation was 1.5 years post-HTx, and pre-sirolimus eGFR was 52 mL/min/1.73 m2 . Nine patients had decreased, 15 stable, and 75 increased, relative combined drug levels. Relative change in eGFR was significantly higher in patients with decreased levels compared to patients with increased levels at 6 months post-initiation (P < .05), but this was not sustained at 12 months. There were no differences in LVEF change or in individual and composite risks for developing DSA, ACR, and all-cause mortality at 12 months across the groups. CONCLUSION: Post-sirolimus initiation, a relative decrease in combined drug levels, compared to increased levels, was associated with temporarily improved renal function.

Induction therapy in heart transplantation: A systematic review and network meta-analysis for developing evidence-based recommendations.

INTRODUCTION: Induction therapy (IT) utility in heart transplantation (HT) remains contested. Commissioned by a clinical-practice guidelines panel to evaluate the effectiveness and safety of IT in adult HT patients, we conducted this systematic review and network meta-analysis (NMA). METHODS: We searched for studies from January 2000 to October 2022, reporting on the use of any IT agent in adult HT patients. Based on patient-important outcomes, we performed frequentist NMAs separately for RCTs and observational studies with adjusted analyses, and assessed the certainty of evidence using the GRADE framework. RESULTS: From 5156 publications identified, we included 7 RCTs and 12 observational studies, and report on two contemporarily-used IT agents-basiliximab and rATG. The RCTs provide only very low certainty evidence and was uninformative of the effect of the two agents versus no IT or one another. With low certainty in the evidence from observational studies, basiliximab may increase 30-day (OR 1.13; 95% CI 1.06-1.20) and 1-year (OR 1.11; 95% CI 1.02-1.22) mortality compared to no IT. With low certainty from observational studies, rATG may decrease 5-year cardiac allograft vasculopathy (OR .82; 95% CI .74-.90) compared to no IT, as well as 30-day (OR .85; 95% CI .80-.92), 1-year (OR .87; 95% CI .79-.96), and overall (HR .84; 95% CI .76-.93) mortality compared to basiliximab. CONCLUSION: With low and very low certainty in the synthetized evidence, these NMAs suggest possible superiority of rATG compared to basiliximab, but do not provide compelling evidence for the routine use of these agents in HT recipients.

Use of induction therapy post-heart transplantation: Clinical practice recommendations based on systematic review and network meta-analysis of evidence.

BACKGROUND: The use of induction therapy (IT) agents in the early post-heart transplant period remains controversial. The following recommendations aim to provide guidance on the use of IT agents, including Basiliximab and Thymoglobulin, as part of routine care in heart transplantation (HTx). METHODS: We recruited an international, multidisciplinary panel of 15 stakeholders, including patient partners, transplant cardiologists and surgeons, nurse practitioners, pharmacists, and methodologists. We commissioned a systematic review on benefits and harms of IT on patient-important outcomes, and another on patients' values and preferences to inform our recommendations. We used the GRADE framework to summarize our findings, rate certainty in the evidence, and develop recommendations. The panel considered the balance between benefits and harms, certainty in the evidence, and patient's values and preferences, to make recommendations for or against the routine post-operative use of Thymoglobulin or Basiliximab. RESULTS: The panel made recommendations on three major clinical problems in HTx: (1) We suggest against the routine post-operative use of Basiliximab compared to no IT, (2) we suggest against the routine use of Thymoglobulin compared to no IT, and (3) for those patients for whom IT is deemed desirable, we suggest for the use of Thymoglobulin as compared to Basiliximab. CONCLUSION: This report highlights gaps in current knowledge and provides directions for clinical research in the future to better understand the clinical utility of IT agents in the early post heart transplant period, leading to improved management and care.

Patients with fulminant myocarditis supported with veno-arterial extracorporeal membrane oxygenation: a systematic review and meta-analysis of short-term mortality and impact of risk factors.

Fulminant myocarditis (FM) may lead to cardiogenic shock requiring veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Results of effectiveness studies of VA-ECMO have been contradictory. We evaluated the aggregate short-term mortality after VA-ECMO and predictive factors in patients with FM. We systematically searched in electronic databases (February 2022) to identify studies evaluating short-term mortality (defined as mortality at 30 days or in-hospital) after VA-ECMO support for FM. We included studies with 5 or more patients published after 2009. We assessed the quality of the evidence using the QUIPS and GRADE tools. Mortality was pooled using random effect models. We performed meta-regression to explore heterogeneity based on a priori defined factors. We included 54 observational studies encompassing 2388 FM patients supported with VA-ECMO. Median age was 41 years (25th to 75th percentile 37-47), and 50% were female. The pooled short-term mortality was 35% (95% CI 29-40%, I2 = 69%; moderate certainty). By meta-regression, studies with younger populations showed lower mortality. Female sex, receiving a biopsy, cardiac arrest, left ventricular unloading, and earlier recruitment time frame, did not explain heterogeneity. These results remained consistent regardless of continent and the risk of bias category. In individual studies, low pH value, high lactate, absence of functional cardiac recovery on ECMO, increased burden of malignant arrhythmia, high peak coronary markers, and IVIG use were identified as independent predictors of mortality. When conventional therapies have failed, especially in younger patients, cardiopulmonary support with VA-ECMO should be considered in the treatment of severe FM.

Prognostic value of blood pressure in ambulatory heart failure: a meta-analysis and systematic review. Ambulatory blood pressure predicts heart failure prognosis.

Previous primary studies have explored the association between blood pressure (BP) and mortality in ambulatory heart failure (HF) patients reporting varying and contrasting associations. The aim is to determine the pooled BP prognostic value and explore potential reasons for between-study inconsistency. We searched Medline, Cochrane, EMBASE and CINAHL from January 2005 to October 2018 for studies with ≥ 50 events (mortality and/or hospitalization) and included BP in a multivariable model in ambulatory HF patients. We pooled hazard ratios (random effects model) for systolic BP (SBP) or diastolic BP (DBP) effect on mortality and/or hospitalization risk. We used a priori defined sub-group analyses to explore heterogeneity and GRADE approach to assess the certainty of the evidence. Seventy-one eligible articles (239,467 screened) at low to moderate risk of bias included 235,752 participants. Higher SBP was associated with reduced all-cause mortality (HR 0.93, 95%CI 0.91-0.95, I2 = 87.13%, moderate certainty), all-cause hospitalization events (HR 0.91, 95%CI 0.88-0.93, I2 = 44.4%, high certainty) and their composite endpoint (HR 0.93 per 10 mmHg, 95%CI 0.91-0.94, I2 = 86.3%, high certainty). DBP did not demonstrate a statistically significant effect for all outcomes. The association strength was significantly weaker in studies following patients with either LVEF > 40%, higher average SBP (> 130 mmHg), increasing age and diabetes. All other a priori subgroup hypotheses did not explain between study differences. Higher ambulatory SBP is associated with reduced risk of all-cause mortality and hospitalization. Patients with lower BP and reduced LVEF are in a high-risk group of developing adverse events with moderate certainty of evidence.

Impact of serial measurements of tricuspid annular plane systolic excursion on mortality and morbidity after heart transplantation.

The impact of right ventricular (RV) dysfunction on long-term post-HTx outcomes remains uncertain. We assessed the impact of serial measurements of Tricuspid Annular Plane Systolic Excursion (TAPSE) on post-HTx mortality and morbidity. This two-center retrospective cohort study included consecutive adult HTx recipients (2000-2017). We used multivariable extended hazard regression models to evaluate the association between TAPSE and left ventricular ejection fraction (LVEF), entered as time-dependent variables, and all-cause mortality, cardiac allograft vasculopathy (CAV), acute cellular rejection (ACR), and chronic kidney disease (CKD). TAPSE was modelled using cubic splines. We included 485 HTx recipients (9461 TAPSE measurements), median (25th- 75th percentile) 19 (10-27) mm; median age was 52 (41-59) years, and 71.3% were male. During a follow-up of 6.7 (3.0-10.8) years, 92 patients died, 225 had ACR >2R, 234 CAV, and 91 CKD. By multivariable analysis, for each 1-mm decrease in patients with a TAPSE value <15mm, mortality increased by 22% (P<.001). For the average HTx recipient with a TAPSE of 15mm, 10mm, and 6mm, 1-year mortality was 3%, 7%, and 17%, and 5-year mortality was 8%, 20%, and 43%, respectively. Reduced TAPSE was significantly associated with increased CAV but notACR and CKD. A decrease in TAPSE below 15mm represents clinically significant graft dysfunction, warranting close monitoring.

Utility of the INTERMACS profile at the time of assessment for heart transplant.

The Interagency Registry of Mechanically Assisted Circulatory Support (INTERMACS) profiles are associated with mortality in heart failure patients undergoing ventricular assist device (VAD) implantation and heart transplantation (HTx). We assessed the prognostic value of the INTERMACS profile at the time of assessment for HTx or durable VAD implantation as bridge to candidacy (BTC). A total of 503 consecutive patients considered for HTx or VAD between 2006 and 2016 were included. The associations between INTERMACS profile and (a) waitlist mortality or delisting, (b) probability of HTx, and (c) overall mortality or delisting were evaluated using multivariable analysis. Median follow-up time was 2.9 years (IQR: 0.9-5.5) during which 184 received VAD, 347 received HTx, and 73 died (27 waitlist, 46 post-transplant). INTERMACS I-II profile was associated with higher waitlist mortality or delisting (HR: 3.83, 95% CI: 1.22-12.03), and this risk was reversed by VAD implantation (HR: 0.12, 95% CI: 0.03-0.50). INTERMACS III-IV profile was associated with a higher probability of HTx (HR: 1.82, 95% CI: 1.37-2.40). INTERMACS profile was not associated with the composite outcome of overall mortality or delisting. These results emphasize the prognostic utility of INTERMACS at time of decision for advanced therapies and its potential value in selecting patients for different interventions.

Clinical presentation and outcomes in women and men with advanced heart failure.

OBJECTIVE: To examine clinical characteristics and outcomes in women and men referred for advanced heart failure (HF) therapies such as left ventricular assist device (LVAD) or heart transplantation (HTx). Design: A retrospective study of 429 (23% women) consecutive adult HF patients not on inotropic or mechanical circulatory support with left ventricular ejection fraction ≤45% referred for assessment of advanced HF therapies at a single tertiary institution between 2002 and 2016. Clinical characteristics and outcomes were compared in women and men, and all patients underwent right heart catheterization (RHC). Results: At evaluation, women were younger than men (48 ± 13 vs. 51 ± 12 years, p = .02), and less likely to have ischemic cardiomyopathy. There were no significant differences in NYHA class, contemporary HF therapy use, or physical examination findings, except for lower jugular vein distension and body surface area in women. On RHC, women had lower cardiac filling pressures, but similar pulmonary vascular resistance and cardiac index. Peak oxygen uptake from cardiopulmonary exercise testing was similar in both sexes. At total follow-up time, there were 164 deaths (21% vs. 44%, p < .0001), 46 LVADs (3% vs. 13%, p = .005), 110 HTxs (32% vs. 25%, p = .15), and 82 HTxs without requiring LVAD (29% vs. 16%, p = .03) in women and men. The time from RHC to HTx (±LVAD) was significantly shorter in women compared to men. Female sex was significantly associated with higher survival independent of time-trend, age, and comorbidities. Conclusion: At evaluation, hemodynamics were less deranged in women. A higher proportion of women received HTx, their waitlist time was shorter, and survival greater.

Evaluation of a Heart Failure Telemonitoring Program Through a Microsimulation Model: Cost-Utility Analysis.

BACKGROUND: Heart failure (HF) is a major public health issue in Canada that is associated with high prevalence, morbidity, and mortality rates and high financial and social burdens. Telemonitoring (TM) has been shown to improve all-cause mortality and hospitalization rates in patients with HF. The Medly program is a TM intervention integrated as standard of care at a large Canadian academic hospital for ambulatory patients with HF that has been found to improve patient outcomes. However, the cost-effectiveness of the Medly program is yet to be determined. OBJECTIVE: This study aims to conduct a cost-utility analysis of the Medly program compared with the standard of care for HF in Ontario, Canada, from the perspective of the public health care payer. METHODS: Using a microsimulation model, individual patient data were simulated over a 25-year time horizon to compare the costs and quality-adjusted life years (QALYs) between the Medly program and standard care for patients with HF treated in the ambulatory care setting. Data were sourced from a Medly Program Evaluation study and literature to inform model parameters, such as Medly's effectiveness in reducing mortality and hospitalizations, health care and intervention costs, and model transition probabilities. Scenario analyses were conducted in relation to HF severity and TM deployment models. One-way deterministic effectiveness analysis and probabilistic sensitivity analysis were performed to explore the impact on the results of uncertainty in model parameters. RESULTS: The Medly program was associated with an average total cost of Can $102,508 (US $77,626) per patient and total QALYs of 5.51 per patient compared with the average cost of Can $97,497 (US $73,831) and QALYs of 4.95 per patient in the Standard Care Group. This led to an incremental cost of Can $5011 (US $3794) and incremental QALY of 0.566, resulting in an incremental cost-effectiveness ratio of Can $8850 (US $6701)/QALY. Cost-effectiveness improved in relation to patients with advanced HF and with deployment models in which patients used their own equipment. Baseline and alternative scenarios consistently showed probabilities of cost-effectiveness greater than 85% at a willingness-to-pay threshold of Can $50,000 (US $37,718). Although the results showed some sensitivity to assumptions about effectiveness parameters, the intervention was found to remain cost-effective. CONCLUSIONS: The Medly program for patients with HF is cost-effective compared with standard care using commonly reported willingness-to-pay thresholds. This study provides evidence for decision makers on the use of TM for HF, supports the use of a nurse-led model of TM that embeds clinically validated algorithms, and informs the use of economic modeling for future evaluations of early-stage health informatics technology.

Discrimination and Calibration of Clinical Prediction Models: Users' Guides to the Medical Literature.

Accurate information regarding prognosis is fundamental to optimal clinical care. The best approach to assess patient prognosis relies on prediction models that simultaneously consider a number of prognostic factors and provide an estimate of patients' absolute risk of an event. Such prediction models should be characterized by adequately discriminating between patients who will have an event and those who will not and by adequate calibration ensuring accurate prediction of absolute risk. This Users' Guide will help clinicians understand the available metrics for assessing discrimination, calibration, and the relative performance of different prediction models. This article complements existing Users' Guides that address the development and validation of prediction models. Together, these guides will help clinicians to make optimal use of existing prediction models.

The Added Value of Exercise Variables in Heart Failure Prognosis.

INTRODUCTION: Diminished exercise capacity is a key symptom in heart failure (HF). Exercise predictors (peak VO2, VE/VCO2 slope, and oxygen uptake efficiency slope [OUES]) are prognostic markers but studied in isolation. We evaluated if these exercise variables offer additional prognostic value to clinical predictors in HF. METHODS AND RESULTS: This was a single-institution retrospective cohort study of 517 consecutive HF patients. We used Cox proportional hazards modeling to determine the additional prognostic value of exercise variables on mortality, HF hospital admissions, and a composite outcome of ventricular assistance device (VAD) implantation, heart transplantation (HT), and death. During a mean follow-up of 2.7 years, 52 deaths, 47 HTs, and 19 VAD implantations occurred. After adjusting for age, New York Heart Association functional class, ejection fraction, body mass index, creatinine, and B-type natriuretic peptide, peak VO2 (hazard ratio [HR] 0.91, 95% confidence interval [CI] 0.85-0.96), OUES (HR 0.92, 95% CI 0.87-0.97), and VE/VCO2 (HR 1.03, 95% CI 1.01-1.05) were independent predictors of the composite outcome. Similar discriminatory capacity existed between the exercise variables (c-statistics 0.77, 0.78, and 0.78, respectively). Only VE/VCO2 was an independent predictor of admissions (HR 1.04, 95% CI 1.01-1.07), and only peak VO2 was an independent predictor of mortality (HR 0.90, 95% CI 0.84-0.98). CONCLUSIONS: Peak VO2, OUES, and VE/VCO2 are independent predictors of HF prognosis over recognized clinical variables. However, no single exercise variable was superior.

C4d immunostaining is an independent predictor of cardiac allograft vasculopathy and death in heart transplant recipients.

Antibody-mediated rejection (AMR) occurs in 10-20% of patients after heart transplantation. C4d immunostaining is one parameter used in its diagnosis. This study aimed to determine whether C4d staining has prognostic significance for mortality, coronary allograft vasculopathy (CAV), cell-mediated rejection (CMR), and graft dysfunction in patients post-transplantation. Consecutive patients receiving an endomyocardial biopsy between 2007 and 2008 were selected. Left ventricular function, angiography, episodes of AMR/CMR, and death were noted. C4d was graded from 0 to 3 (immunostaining). Cox proportional models (recurrent events analysis) were used to evaluate C4d staining with mortality, graft dysfunction, CAV (≥grade 2), and episodes of ≥2R-CMR. We analyzed 2525 biopsy specimens (n = 217). During a follow-up of 4.5 ± 2 years, 35 died, 49 had graft dysfunction, seven had ≥grade 2 CAV, and 95 episodes of CMR occurred. A one-grade increase in C4d staining was associated with an increase in mortality (HR 1.57; 95% CI 1.0-2.5), a higher risk of CAV (HR 2.4, 95% CI 1.04-5.4), and a trend toward graft dysfunction (HR 1.42; 95% CI 1.0-2.09). C4d was not associated with CMR. C4d immunostaining was a significant predictor of CAV and death but not subsequent episodes of CMR. There was also a trend toward increased graft failure.

Predicting heart failure outcomes by integrating breath-by-breath measurements from cardiopulmonary exercise testing and clinical data through a deep learning survival neural network.

Aims: Mathematical models previously developed to predict outcomes in patients with heart failure (HF) generally have limited performance and have yet to integrate complex data derived from cardiopulmonary exercise testing (CPET), including breath-by-breath data. We aimed to develop and validate a time-to-event prediction model using a deep learning framework using the DeepSurv algorithm to predict outcomes of HF. Methods and results: Inception cohort of 2490 adult patients with high-risk cardiac conditions or HF underwent CPET with breath-by-breath measurements. Potential predictive features included known clinical indicators, standard summary statistics from CPETs, and mathematical features extracted from the breath-by-breath time series of 13 measurements. The primary outcome was a composite of death, heart transplant, or mechanical circulatory support treated as a time-to-event outcomes. Predictive features ranked as most important included many of the features engineered from the breath-by-breath data in addition to traditional clinical risk factors. The prediction model showed excellent performance in predicting the composite outcome with an area under the curve of 0.93 in the training and 0.87 in the validation data sets. Both the predicted vs. actual freedom from the composite outcome and the calibration of the prediction model were excellent. Model performance remained stable in multiple subgroups of patients. Conclusion: Using a combined deep learning and survival algorithm, integrating breath-by-breath data from CPETs resulted in improved predictive accuracy for long-term (up to 10 years) outcomes in HF. DeepSurv opens the door for future prediction models that are both highly performing and can more fully use the large and complex quantity of data generated during the care of patients with HF.

GRADE concept paper 8: judging the certainty of discrimination performance estimates of prognostic models in a body of validation studies.

BACKGROUND: Prognostic models incorporate multiple prognostic factors to estimate the likelihood of future events for individual patients based on their prognostic factor values. Evaluating these models crucially involves conducting studies to assess their predictive performance, like discrimination. Systematic reviews and meta-analyses of these validation studies play an essential role in selecting models for clinical practice. METHODS: In this paper, we outline 3 thresholds to determine the target for certainty rating in the discrimination of prognostic models, as observed across a body of validation studies. RESULTS AND CONCLUSION: We propose 3 thresholds when rating the certainty of evidence about a prognostic model's discrimination. The first threshold amounts to rating certainty in the model's ability to classify better than random chance. The other 2 approaches involve setting thresholds informed by other mechanisms for classification: clinician intuition or an alternative prognostic model developed for the same disease area and outcome. The choice of threshold will vary based on the context. Instead of relying on arbitrary discrimination cut-offs, our approach positions the observed discrimination within an informed spectrum, potentially aiding decisions about a prognostic model's practical utility.

Better Respiratory Function in Heart Failure Patients With Use of Central-Acting Therapeutics.

Background: Diaphragm atrophy can contribute to dyspnea in patients with heart failure (HF) with its link to central neurohormonal overactivation. HF medications that cross the blood-brain barrier could act centrally and improve respiratory function, potentially alleviating diaphragmatic atrophy. Therefore, we compared the benefit of central- vs peripheral-acting HF drugs on respiratory function, as assessed by a single cardiopulmonary exercise test (CPET) and outcomes in HF patients. Methods: A retrospective study was conducted of 624 ambulatory adult HF patients (80% male) with reduced left ventricular ejection fraction ≤ 40% and a complete CPET, followed at a single institution between 2001 and 2017. CPET parameters, and the outcomes all-cause death, a composite endpoint (all-cause death, need for left ventricular assist device, heart transplantation), and all-cause and/or HF hospitalizations, were compared in patients receiving central-acting (n = 550) vs peripheral-acting (n = 74) drugs. Results: Compared to patients who receive peripheral-acting drugs, patients who receive central-acting drugs had better respiratory function (peak breath-by breath oxygen uptake [VO2], P = 0.020; forced expiratory volume in 1 second [FEV1], P = 0.007), and ventilatory efficiency (minute ventilation / carbon dioxide production [VE/VCO2], P < 0.001; end-tidal carbon dioxide tension [PETCO2], P = 0.015; and trend for forced vital capacity [FVC], P = 0.056). Many of the associations between the CPET parameters and drug type remained significant after multivariate adjustment. Moreover, patients receiving central-acting drugs had fewer composite events (P = 0.023), and HF hospitalizations (P = 0.044), although significance after multivariant correction was not achieved, despite the hazard ratio being 0.664 and 0.757, respectively. Conclusions: Central-acting drugs were associated with better respiratory function as measured by CPET parameters in HF patients. This could extend to clinically meaningful composite outcomes and hospitalizations but required more power to be definitive in linking to drug effect. Central-acting HF drugs show a role in mitigating diaphragm weakness.

Contexte: L'atrophie du diaphragme peut contribuer à la dyspnée chez les personnes atteintes d'insuffisance cardiaque (IC), compte tenu de son lien avec la suractivation neuro-hormonale centrale. Or, les médicaments contre l'IC qui franchissent la barrière hématoencéphalique pourraient exercer une action centrale, améliorer la respiration et ainsi éventuellement atténuer l'atrophie du diaphragme. C'est pourquoi nous avons voulu comparer, au moyen d'une seule épreuve d'effort cardiopulmonaire (EECP), les effets bénéfiques exercés par des médicaments à action périphérique et des médicaments à action centrale sur la fonction respiratoire, de même que l'issue des patients atteints d'IC auxquels ils ont été administrés. Méthodologie: Nous avons réalisé une étude rétrospective auprès de 624 adultes ambulatoires atteints d'IC (80 % d'hommes) dont la fraction d'éjection ventriculaire gauche était réduite (≤ 40 %), qui se sont prêtés à une EECP complète et qui ont été suivis dans le même établissement entre 2001 et 2017. Les paramètres de l'EECP et la mortalité toutes causes confondues, un critère d'évaluation composé (décès toutes causes confondues, nécessité de recourir à un dispositif d'assistance ventriculaire gauche, transplantation cardiaque), et les hospitalisations toutes causes confondues et/ou liées à l'IC ont été comparés entre les patients qui recevaient des médicaments à action centrale (n = 550) et ceux qui recevaient des médicaments à action périphérique (n = 74). Résultats: Comparativement aux patients ayant reçu des médicaments à action périphérique, ceux qui ont reçu des médicaments à action centrale ont bénéficié d'une meilleure fonction respiratoire (consommation maximale d'oxygène [VO2], p = 0,020; volume expiratoire maximal par seconde [VEMS], p = 0,007) et d'une meilleure efficacité ventilatoire (ventilation minute/production de dioxyde de carbone [VE/VCO2], p < 0,001; pression partielle de dioxyde de carbone en fin d'expiration [PETCO2], p = 0,015; et tendance de la capacité vitale forcée [CVF], p = 0,056). De plus, bon nombre des associations entre les paramètres de l'EECP et le type de médicament sont demeurées significatives après ajustement multivarié. Les patients qui ont reçu des médicaments à action centrale ont également présenté moins d'événements faisant partie du critère d'évaluation composé (p = 0,023) et moins d'hospitalisations liées à l'IC (p = 0,044), même si la différence après correction multivariée n'a pas été significative et que les rapports de risques étaient respectivement de 0,664 et de 0,757. Conclusions: Les médicaments à action centrale ont été associés à une meilleure fonction respiratoire, mesurée à l'aide des paramètres d'une EECP, chez les patients atteints d'IC. Ce résultat pourrait également s'appliquer au critère d'évaluation composé et aux hospitalisations, mais une étude plus puissante est nécessaire pour établir un lien cliniquement significatif avec l'effet des médicaments. Les médicaments à action centrale contre l'IC ont donc un rôle à jouer dans la correction de la faiblesse du diaphragme.

Online resources as a source of information for exercise and physical activity in solid organ transplant recipients.

Introduction: Exercise training post-transplant has been shown to improve physical function and quality of life in solid organ transplant (SOT) recipients. Online resources in the form of websites and videos are commonly used to provide education and instruction on exercise and physical activity in SOT; however, the content and quality of these online resources has not been evaluated. Methods: The first 200 websites and videos identified on Google and YouTube using the English search term "exercise and physical activity in solid organ transplantation" were analyzed. Website and video content was evaluated based on 25 key components of exercise and physical activity in SOT as described in established exercise program recommendations. Website and video quality was determined using DISCERN, Global Quality Scale (GQS), and Patient Education Materials and Assessment Tool (PEMAT; threshold for which material is deemed understandable or actionable is >70%). Parametric and non-parametric tests were used to assess website and video characteristics, content, and quality metrics. Results: Forty-nine unique SOT websites (n = 15) and videos (n = 34) were identified, with the two most common categories being foundation/advocacy organizations and scientific resources. The average reading grade level of websites was 13 ± 3. Website and video content scores varied significantly (websites 11.3 ± 6.4; videos 8.4 ± 5.3). DISCERN total score and GQS score were low (median range for DISCERN 2.5-3.0; median for GQS 2.0 for both websites and videos, out of 5). PEMAT understandability and actionability scores were also low across websites and videos (mean range 57%-67% and 47%-65%, respectively). Foundation/advocacy websites had higher content and quality scores compared to scientific organizations and news/media articles. Conclusions: To our knowledge, this is the first comprehensive assessment of online content and quality of website and video resources on physical activity and exercise in adult SOT recipients. There were a limited number of online English patient-directed resources related to physical activity in SOT, most of which only partly captured items outlined in consensus exercise program recommendations and were of low quality and understandability and actionability. This work provides important insight to the English-speaking transplant community on the current state of online exercise health information and provides future direction for resource development.

Association Between the Incidence of Hospitalizations for Acute Cardiovascular Events, Weather, and Air Pollution.

Background: The incidence of hospitalizations for cardiovascular events has been associated with specific weather conditions and air pollution. A comprehensive model including the interactions between various environmental factors remains to be developed. Objectives: The purpose of this study was to develop a comprehensive model of the association between weather patterns and the incidence of cardiovascular events and use this model to forecast near-term spatiotemporal risk. Methods: We present a spatiotemporal analysis of the association between atmospheric data and the incidence rate of hospital admissions related to heart failure (922,132 episodes), myocardial infarction (521,988 episodes), and ischemic stroke (263,529 episodes) in ∼24 million people in Canada between 2007 and 2017. Our hierarchical Bayesian model captured the spatiotemporal distribution of hospitalizations and identified weather and air pollution-related factors that could partially explain fluctuations in incidence. Results: Models that included weather and air pollution variables outperformed models without those covariates for most event types. Our results suggest that environmental factors may interact in complex ways on human physiology. The impact of environmental factors was magnified with increasing age. The weather and air pollution variables included in our models were predictive of the future incidence of heart failure, myocardial infarction, and ischemic strokes. Conclusions: The increasing importance of environmental factors on cardiovascular events with increasing age raises the need for the development of educational materials for older patients to recognize environmental conditions where exacerbations are more likely. This model could be the basis of a forecasting system used for local, short-term clinical resource planning based on the anticipated incidence of events.

GRADE guidance 36: updates to GRADE's approach to addressing inconsistency.

OBJECTIVES: To update previous Grading of Recommendations Assessment, Development and Evaluation (GRADE) guidance by addressing inconsistencies and interpreting subgroup analyses. STUDY DESIGN AND SETTING: Using an iterative process, we consulted with members of the GRADE working group through multiple rounds of written feedback and discussions at GRADE working group meetings. RESULTS: The guidance complements previous guidance with clarification in two areas: (1) assessing inconsistency and (2) assessing the credibility of possible effect modifiers that might explain inconsistency. Specifically, the guidance clarifies that inconsistency refers to variability in results, not in study characteristics; that inconsistency assessment for binary outcomes requires consideration of both relative and absolute effects; how to decide between narrower and broader questions in systematic reviews and guidelines; that, with the same evidence, ratings of inconsistency may differ depending on the target of certainty rating; and how GRADE inconsistency ratings relate to a statistical measure of inconsistency I2 depending on the context in which one views results. The second part of the guidance illustrates, based on a worked example, the use of the instrument to assess the credibility of effect modification analyses. The guidance explains the stepwise process of moving from a subgroup analysis to assessing the credibility of effect modification and, if found credible, to subgroup-specific effect estimates and GRADE certainty ratings. CONCLUSION: This updated guidance addresses specific conceptual and practical issues that systematic review authors frequently face when considering the degree of inconsistency in estimates of treatment effects across studies.

Predictors of Mortality in Patients Treated with Veno-Arterial ECMO for Cardiogenic Shock Complicating Acute Myocardial Infarction: a Systematic Review and Meta-Analysis.

BACKGROUND: Mortality for patients on veno-arterial extracorporeal membrane oxygenation (VA-ECMO) for cardiogenic shock (CS) complicating acute myocardial infarction (AMI) remains high. This meta-analysis aims to identify factors that predict higher risk of mortality after VA-ECMO for AMI. METHODS: We meta-analyzed mortality after VA-ECMO for CS complicating AMI and the effect of factors from systematically selected studies published after 2009. RESULTS: 72 studies (10,276 patients) were included with a pooled mortality estimate of 58 %. With high confidence in estimates, failure to achieve TIMI III flow and left main culprit were identified as factors associated with higher mortality. With low-moderate confidence, older age, high BMI, renal dysfunction, increasing lactate, prothrombin activity < 50%, VA-ECMO implantation after revascularization, and non-shockable ventricular arrythmias were identified as factors associated with mortality. CONCLUSION: These results provide clinicians with a framework for selecting patients for VA-ECMO for CS complicating AMI.