Proteomic analysis of extracellular vesicle cargoes mirror the cardioprotective effects of rivaroxaban in patients with venous thromboembolism

BACKGROUND

Venous thromboembolism (VTE) remains a significant cause of morbidity and mortality worldwide. Rivaroxaban, a direct oral factor Xa inhibitor, mediates anti-inflammatory and cardiovascular-protective effects besides its well-established anticoagulant properties; yet, these remain poorly characterized. Extracellular vesicles (EVs) are considered proinflammatory messengers regulating a myriad of (patho)physiological processes and may be highly relevant to the pathophysiology of VTE. The effects of Rivaroxaban on circulating EVs in VTE patients remain unknown. We have established that differential EV biosignatures are found in patients with non-valvular atrial fibrillation anticoagulated with Rivaroxaban versus warfarin. Here, we investigated whether differential proteomic profiles of circulating EVs could also be found in patients with VTE.

METHODS AND RESULTS

We performed comparative label-free quantitative proteomic profiling of enriched plasma EVs from VTE patients anticoagulated with either Rivaroxaban or warfarin using a tandem mass spectrometry approach. Of the 182 quantified proteins, six were found to be either exclusive to, or enriched in, Rivaroxaban-treated patients. Intriguingly, these proteins are involved in negative feedback regulation of inflammatory and coagulation pathways, suggesting that EV proteomic signatures may reflect both Rivaroxaban's anti-coagulatory and anti-inflammatory potential.

CONCLUSIONS

These differences suggest Rivaroxaban may have pleiotropic effects, supporting the reports of its emerging anti-inflammatory and cardiovascular-protective characteristics relative to warfarin.

Clinical Frailty Scale as a predictor of adverse outcomes following aortic valve replacement: a systematic review and meta-analysis

OBJECTIVES

Assessment of frailty prior to aortic valve intervention is recommended in European and North American valvular heart disease guidelines. However, there is a lack of consensus on how it is best measured. The Clinical Frailty Scale (CFS) is a well-validated measure of frailty that is relatively quick to calculate. This meta-analysis sought to examine whether the CFS predicts mortality and morbidity following either transcatheter aortic valve implantation (TAVI) or surgical aortic valve replacement (SAVR).

METHODS

Nine electronic databases were searched systematically for data on clinical outcomes post-TAVI/SAVR, where patients had undergone preoperative frailty assessment using the CFS. The primary endpoint was 12-month mortality. TAVI and SAVR data were assessed and reported separately. For each individual study, the incidence of adverse outcomes was extracted according to a CFS score of 5-9 (ie, frail) versus 1-4 (ie, non-frail), with meta-analysis performed using a random effects model.

RESULTS

Of 2612 records screened, nine were included in the review (five TAVI, three SAVR and one which included both interventions). Among 4923 TAVI patients, meta-analysis showed 12-month mortality rates of 19.1% for the frail cohort versus 9.8% for the non-frail cohort (RR 2.53 (1.63 to 3.95), p<0.001, I2=83%). For the smaller cohort of SAVR patients (n=454), mortality rates were 20.3% versus 3.9% for the frail and non-frail cohorts, respectively (RR 5.08 (2.31 to 11.15), p<0.001, I2=5%).

CONCLUSIONS

Frailty, as determined by the CFS, was associated with an increased mortality risk in the 12 months following either TAVI or SAVR. These data would support its use in the preoperative assessment of elderly patients undergoing aortic valve interventions.

Octreotide for Acquired Chylothorax in Pediatric Patients Post-Cardiothoracic Surgery for Congenital Heart Disease: A Systematic Review

Chylothorax is a life-threatening complication post-corrective congenital heart surgery. Octreotide is used for treatment of refractory chylothoraces, with no standardized treatment protocol and a paucity of literature describing its efficacy. Our aim was to provide an update on the safety and efficacy of octreotide for the treatment of refractory chylothoraces in neonatal and pediatric patients' post-corrective congenital heart surgery. We performed a systematic review of PubMed, Medline, CINAHL, and Cochrane Library databases. Only intravenous octreotide treatment was included. A total of 621 patients across 27 studies were included. Studies included were 11 case series, 5 case studies, and 11 retrospective cohort studies. Variation in treatment regimens were reported. Treatment efficacy was reported in 95% (23/27) of studies. Definitions of treatment efficacy were reported in 33% (9/27) of studies. No prospective or randomized control trials were available for inclusion. Octreotide efficacy is widely reported despite a lack of standardization on criteria for treatment initiation or what defines an appropriate response to therapy.Please check and confirm whether the edit made to the article title is in order.Yes.

Improving the Quality of Paediatric ECG Interpretation

Aims Our aim was to complete an audit loop and identify whether implementing a paediatric ECG checklist improved the documentation and therefore the quality of paediatric ECG interpretation. We designed a paediatric ECG and education proforma in a Paediatric Emergency Department and incorporated it into daily practice. Methods We audited the medical records of children presenting with clinical indications for ECG. We included 40 records before and 40 records after the introduction of a paediatric ECG interpretation checklist. Results We assessed 10 items of documentation of which 8 related to the wave-form. Recording of these ranged from 0-65% before and from 95-100% after the checklist. Conclusion An intervention to introduce a paediatric ECG checklist, including education proforma, demonstrated significant improvement in the interpretation and documentation of a paediatric ECG. We recommend the use of this checklist in primary care and hospital settings.

Measuring Frailty to Determine the Likelihood of Poor Outcomes Following Aortic Valve Replacement: Can the Rockwood Clinical Frailty Scale Prove Useful?

The importance of frailty as a pre-operative determinant of outcomes following aortic valve replacement has been highlighted in recent years. While particularly frail patients would previously have been deemed unsuitable for traditional Surgical Aortic Valve Replacement (SAVR), the growth of Transcatheter Aortic Valve Implantation (TAVI) as an alternative has thrust this issue into the spotlight.

Rockwood Clinical Frailty Scale as a predictor of adverse outcomes among older adults undergoing aortic valve replacement: a protocol for a systematic review

INTRODUCTION

Frailty is associated with adverse outcomes relating to cardiac procedures. It has been proposed that frailty scoring should be included in the preoperative assessment of patients undergoing aortic valve replacement. We aim to examine the Rockwood Clinical Frailty Scale (CFS), as a predictor of adverse outcomes following aortic valve replacement.

METHODS AND ANALYSIS

Prospective and retrospective cohort studies and randomised controlled trials assessing both the preoperative frailty status (as per the CFS) and incidence of adverse outcomes among older adults undergoing either surgical aortic valve replacement or transcatheter aortic valve replacement will be included. Adverse outcomes will include mortality and periprocedural complications, as well as a composite of 30-day complications. A search will be conducted from 2005 to present using a prespecified search strategy. Studies will be screened for inclusion by two reviewers, with methodological quality assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Relative risk ratios with 95% CIs will be generated for each outcome of interest, comparing frail with non-frail groups. Data will be plotted on forest plots where applicable. The quality of the evidence will be determined using the Grading of Recommendations, Assessment, Development and Evaluation tool.

ETHICS AND DISSEMINATION

Ethical approval is not required for this study as no primary data will be collected. We will publish the review in a peer-reviewed journal on completion.

PROSPERO REGISTRATION NUMBER

CRD42020213757.

241 IMPLEMENTATION OF AN INTRACEREBRAL CEREBRAL HAEMORRHAGE CARE BUNDLE

Background

Mortality for Intracerebral haemorrhage (ICH) is 31% (Irish National Audit Stroke, 2019). An ICH care bundle focusing on acute anticoagulation reversal, blood pressure lowering, and a neurosurgical care pathway was associated with improved survival. Translating evidence-based medicine into clinical practice is challenging. The aim of this study was to determine feasibility and outcomes of implementation of a care bundle.

Methods

An ICH care bundle was developed using an iterative process involving expert stakeholder review of the evidence-based literature. A pre-and-post quasi-experimental research design was employed to evaluate this intervention. Baseline data were collected before implementation (January 2016-June 2018). Implementation took place in a staged manner in a single university teaching hospital with multiple ‘Plan Do Study Act cycles’ (June 2018 to January 2021). Data on compliance, process measures and outcomes were collected.

Results

Systolic blood pressure (first 24-hours) and anticoagulant reversal were significantly better controlled post-implementation (χ2 (1, N = 91) = 5.34, P = 0.02), (χ2 (1, N = 25) = 5.85, P = 0.016), respectively. DNAR orders were significantly lower in the post-implementation group (χ2 (1, N = 25) = 5.85, P = 0.029). However, ‘Do Not Actively Resuscitate’ status did not significantly differ when accounting for low GCS as a surrogate measure for poor prognosis (χ2 (1, N = 34) = 0.00, P = 0.966). Modified Rankin Scale on discharge did not differ significantly pre-and-post-implementation (z = −0.075, P = 0.94). A greater proportion of patients survived in the post-implementation group; however, this was not statistically significant (χ2 (1, N = 133) = 0.77, P = 0.38). Length of stay significantly increased post implementation.

Conclusion

An ICH care bundle was developed based on expert stakeholder feedback. The feasibility of implementing this bundle of care was demonstrated in a real-world clinical practice setting. A cluster-randomized trial or a large registry study is the next step to evaluate the overall impact of this care bundle on patient outcomes.

235 THROMBOLYSIS DOSING AND WEIGHT ESTIMATION IN ACUTE STROKE: A SINGLE CENTRE AUDIT

Background

Stroke is a leading cause of death and disability. Thrombolysis with intravenous (IV) alteplase is the mainstay management of ischaemic stroke. It has a narrow therapeutic window with a high potential for adverse outcomes such as intracranial haemorrhage. The efficacy of alteplase is time and dose dependent with weight-based dosing. National clinical guidelines recommend a dose of 0.9 mg/kg, up to a maximum of 90 mg. (Irish Heart Foundation Council for Stroke 2015). In most hospitals in Ireland however, patients are not weighed prior to thrombolysis. Time pressure and lack of available suitable equipment are factors.

Methods

This retrospective clinical audit evaluated the dosing of alteplase, estimated and actual weight for a convenience sample of stroke thrombolysis patients treated between 2016–2020 at an Irish University Teaching Hospital.

Results

107 patients were audited (62 males, 45 females). Actual and estimated weights were available in 92/107. Weight was not documented (n = 15) due to severe stroke/palliative management (n = 6) or omission (n = 9). 21% (19/92) received the correct dose of 0.9 mg/kg. A further 54% (50/92) received a dose within the range of 0.81–0.99 mg/kg (±10%). 25% received a dose outside this range (&gt; ± 10%). 11% (10/92) were under-thrombolysed and 14% (13/92) over-thrombolysed. 17/92 patients had an intracranial haemorrhage. 35% (n = 6/17) of patients who had an intracranial haemorrhage received a higher dose of thrombolysis (&gt;10%).

Conclusion

A quarter of patients received inappropriate dosing of alteplase that was outside the range of ±10% of 0.9 mg/kg. While stroke thrombolysis must be completed urgently, an accurate weight should be determined to avoid errors in dosing. A process evaluation of stroke thrombolysis would provide information on how best to incorporate an objective means of weight measurement without delaying treatment.

Diagnostic yield from cardiac gene panel testing for inherited cardiac conditions in a large Irish cohort

Background

Inherited cardiomyopathies (hypertrophic, dilated and arrhythmogenic) and cardiac ion channelopathies (long QT, Brugada and CPVT) predispose to sudden cardiac death/sudden arrhythmic death syndrome. Given their genetically heterogenous nature, multi-gene DNA sequencing panels are useful to aid genetic diagnosis.

Purpose

Investigate the diagnostic yield from cardiac gene panel testing undertaken in patients (including molecular autopsy in deceased patients) referred to four clinical services from 2002 to 2020.

Methods

Data was collected by interrogation of departmental databases, family charts, and review of molecular genetic diagnostic reports.

Results

We evaluated molecular genetic diagnostic results from 835 individuals (461 males, 374 females) from 824 families, including 58 deceased patients who underwent molecular autopsy. The median age of the cohort was 44 years (range 0.1–86 years).

Testing for hypertrophic cardiomyopathy (HCM) and long QT syndrome (LQT) genes represented 36% and 32% of the cohort, respectively, with the remaining 32% accounting for other cardiomyopathies, arrhythmia syndromes or metabolic/syndromic diseases. The overall variant detection rate was 50% across all panel types. Three hundred and fifty patients (42%) carried a single variant, 68 patients (8%) carried multiple variants (up to a maximum of four), including two individuals who carried two actionable (pathogenic/likely pathogenic) variants each and 30 individuals (5%) with one actionable variant plus a variant of uncertain significance (VUS).

The overall diagnostic yield of at least one actionable variant was 28%. At least one VUS was detected in 27% of the cohort. Molecular autopsy yielded an actionable variant in 10% of patients, while 30% of the subcohort carried at least one VUS (up to maximum of two).

We found a positive association between female sex and the likelihood of detecting an actionable variant. By decade of age, detection of actionable variants ranged from 19% (60–69 years) to 41% (0–9 years). By panel type, actionable variants ranged from 14% (Brugada) to 35% (cardiomyopathy). The burden of VUS ranged from 22% (LQT) to 46% (dilated cardiomyopathy).

Altogether 234 actionable variants were detected in 26 genes, including seven metabolic or syndromic disease genes. From those with non-metabolic/syndromic forms of disease, 84% of actionable variants were detected in well established ICC genes. Analysis of gene-disease associations for VUS detected from HCM and LQT panels revealed that 10–25% were detected in genes now deemed to have only moderate or limited evidence of disease causation.

Conclusion

Most actionable variants in this cohort were detected in well-established ICC genes, suggesting that large gene panels offer little extra sensitivity compared to historic smaller gene panels. Despite recent gene curation efforts, the high burden of VUS remains a considerable challenge in ICC management.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): National Children's Research Centre

Nonvalvular atrial fibrillation patients anticoagulated with rivaroxaban compared with warfarin exhibit reduced circulating extracellular vesicles with attenuated pro-inflammatory protein signatures

BACKGROUND

Rivaroxaban, a direct oral factor Xa inhibitor, mediates anti-inflammatory and cardiovascular-protective effects besides its well-established anticoagulant properties; however, these remain poorly characterized. Extracellular vesicles (EVs) are important circulating messengers regulating a myriad of biological and pathological processes and may be highly relevant to the pathophysiology of atrial fibrillation as they reflect alterations in platelet and endothelial biology. However, the effects of rivaroxaban on circulating pro-inflammatory EVs remain unknown.

OBJECTIVES

We hypothesized that rivaroxaban's anti-inflammatory properties are reflected upon differential molecular profiles of circulating EVs.

METHODS

Differences in circulating EV profiles were assessed using a combination of single vesicle analysis by Nanoparticle Tracking Analysis and flow cytometry, and proteomics.

RESULTS

We demonstrate, for the first time, that rivaroxaban-treated non-valvular atrial fibrillation (NVAF) patients (n=8) exhibit attenuated inflammation compared with matched warfarin controls (n=15). Circulating EV profiles were fundamentally altered. Moreover, quantitative proteomic analysis of enriched plasma EVs from six pooled biological donors per treatment group revealed a profound decrease in highly pro-inflammatory protein expression and complement factors, together with increased expression of negative regulators of inflammatory pathways. Crucially, a reduction in circulating levels of soluble P-selectin was observed in rivaroxaban-treated patients (compared with warfarin controls), which negatively correlated with the patient's time on treatment.

CONCLUSION

Collectively, these data demonstrate that NVAF patients anticoagulated with rivaroxaban (compared with warfarin) exhibit both a reduced pro-inflammatory state and evidence of reduced endothelial activation. These findings are of translational relevance toward characterizing the anti-inflammatory and cardiovascular-protective mechanisms associated with rivaroxaban therapy.

Safety of Conscious Sedation for Transcatheter Aortic Valve Replacement Without an Anesthetist

OBJECTIVES

To compare the safety of performing transfemoral transcatheter aortic valve replacement (TAVR) under conscious sedation without an anesthetist present (TAVR-NA) vs TAVR performed with an anesthetist supervising sedation (TAVR-A).

BACKGROUND

In almost all United States and European centers, TAVR-A represents the standard of care. There are limited data on the safety of TAVR-NA.

METHODS

The prospective Mater TAVR database was analyzed. Patients undergoing transfemoral TAVR under conscious sedation were identified and divided into 2 groups, ie, TAVR-NA and TAVR-A. Demographics, procedural characteristics, and clinical outcomes for each group were assessed and compared.

RESULTS

From a cohort of 300 patients who underwent transfemoral TAVR under conscious sedation, TAVR-NA and TAVR-A were performed in 85 patients and 215 patients, respectively. Baseline variables were similar except for a higher median Society of Thoracic Surgeons score in the TAVR-NA group vs the TAVR-A group (5.1% vs 4.4% in the TAVR-A group; P=.05). TAVR-A patients had a higher rate of conversion to general anesthesia (4.2% vs 1.2% in the TAVR-NA group; P=.29), with 1 patient in each group requiring conversion to emergency surgery. In-lab and in-hospital complication rates were similar in the TAVR-NA and TAVR-A groups (7.1% vs 6.5% [P=.86] and 8.2% vs 12.1% [P=.34], respectively). The Kaplan-Meier estimate of freedom from mortality and/or stroke at 1 month was comparable between both groups (96.5% vs 97.7%; P=.57).

CONCLUSIONS

In this modest-sized transfemoral TAVR cohort with a low conversion rate to emergency surgery, TAVR-NA was associated with safety outcomes that were equivalent to TAVR-A. In healthcare systems where access to TAVR may be limited by anesthetic resources, TAVR-NA appears to be a reasonable option to enable the application of this therapy.

Commotio Cordis Caused During Hurling Game

A teenage boy had a cardiac arrest following a blow to the chest from a hurling ball (sliotar). Prompt resuscitation and automated external defibrillation enabled a full recovery. This is the first reported case of commotio cordis caused by a sliotar although it is described in other sports. Primary prevention of commotio cordis (CC) and secondary prevention of cardiac death are discussed.

Berry syndrome in association with familial limb malformation

We describe a newborn boy diagnosed with Berry syndrome consisting of a distal aortopulmonary septal defect, aortic origin of the right pulmonary artery, and interruption of the aorta. The child was noted to have reduplication of the right thumb. The child's mother had a claw malformation of her left hand but a normal cardiovascular status. Genetic analysis for TBX5 and SALL4 mutations were negative in both the patient and his mother. This case describes the first ever report of Berry syndrome in an infant with reduplication of the right thumb and familial limb malformation.

Parvovirus B19 infection associated with dilated cardiomyopathy in patients with previous anthracycline exposure

We describe two children with previous anthracycline exposure for cancer who presented with acute decompensated left ventricular dysfunction. Both patients had evidence of dilated cardiomyopathy and required mechanical ventilation and inotropic support. Parvovirus B19 was detected by polymerase chain reaction of the blood. After several weeks of ventilation and inotropic support, both patients were weaned from ventilation and managed with oral carvedilol, ACE inhibition, and diuretics. Acute left ventricular decompensation in patients following anthracycline exposure may not be solely attributed to drug exposure, and viral etiologies should be considered.

Long-term support with milrinone prior to cardiac transplantation in a neonate with left ventricular noncompaction cardiomyopathy

A 2-week-old female infant presented with acute decompensated left ventricular failure. Echocardiography diagnosed left ventricular noncompaction cardiomyopathy with dilated phenotype and a left ventricular shortening fraction <10%. The infant was mechanically ventilated for 2 weeks and then successfully extubated. She was maintained on intravenous milrinone for 6 months until she underwent successful orthotopic heart transplantation. Young children can be supported with inotropes for prolonged periods while awaiting heart transplantation.

Access of asylum seeker children to acute paediatric services

To investigate the interface between primary care and paediatric services in the referral of asylum seekers. Over a 3 month period a questionnaire was administered, and clinical data gathered on every child attending the A&E department of UCHG whose parents were seeking asylum in this country. Control data was obtained for the next Irish child seen on-call. At the time of presentation to the paediatric service, an Irish child was 4 times more likely (32%) to have initially been seen and referred by a GP than an asylum seeker child (8%); 80% of asylum seeker families had registered with a GP, compared to 96% of controls. 24% of asylum seeker families had called and used an emergency response ambulance to get to hospital, compared to just 4% of Irish children. The rate of subsequent admission to the paediatric ward from A&E was nearly that in asylum seeker children (24%) compared to Irish controls (40%), get to hospital, compared to just 4% of Irish children. Asylum seeker children are less likely to have seen a GP prior to A&E presentation, more likely to go to hospital by ambulance and less likely to be subsequently admitted, suggesting an over-dependence on paediatric hospital services in this population.

Large outbreak of E. coli O157 in 2005, Ireland

In October/November 2005, the largest outbreak of verotoxin-producing Escherichia coli (VTEC) ever recorded in Ireland occurred. Eighteen E. coli O157 culture-positive cases, phage type 32, verotoxin 2 positive, were identified in a small rural area of mid-west Ireland. Half of these patients were asymptomatic. Two children were admitted to hospital with haemolytic uraemic syndrome, one of whom required peritoneal dialysis, and both recovered. All 18 culture-positive patients had indistinguishable or closely related pulsed field gel electrophoresis (PFGE) patterns. Nine of the VTEC O157 culture-positive individuals were in preschool children attending two local crèches. Several culture-positive individuals apparently had exposure to a vulnerable private group water scheme (GWS) in an agricultural area. No microbiological evidence of VTEC was found in food or water. One veterinary sample (an animal rectal swab) was positive for E. coli O157 and the PFGE strain was indistinguishable from the outbreak strain. A case control study showed analytical epidemiological evidence of risk related to potential exposure to the GWS but not related to reported consumption of that water. Selection of cases and controls proved challenging. Transmission occurred primarily in childcare and family settings, with significant person-to-person spread. Control measures included voluntary closure of the crèches, exclusion of culture-positive individuals in risk groups until microbiological clearance was achieved and the issuing of a ‘boil water’ advisory for drinking water pending upgrading of disinfection facilities.