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.

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.

Use of Flecainide in Stable Coronary Artery Disease: An Analysis of Its Safety in Both Nonobstructive and Obstructive Coronary Artery Disease.

BACKGROUND: Flecainide is a class IC antiarrhythmic drug that is contraindicated in patients who have a history of myocardial infarction, but its effect on mortality and risk of proarrhythmia in patients with stable obstructive and nonobstructive epicardial coronary artery disease (CAD) has not been assessed. OBJECTIVE: We sought to compare the safety of flecainide administration in patients who had angiographic evidence of either no or minimal CAD versus nonobstructive CAD, and those who underwent nuclear stress testing with perfusion defects versus those without perfusion defects. METHODS: We conducted a retrospective chart review of 348 patients who were treated with flecainide for at least 1 year duration and underwent evaluation for CAD with coronary angiography or myocardial perfusion imaging (MPI) stress testing within 3 months of initiating flecainide. We compared overall mortality and proarrhythmia between varying levels of CAD and perfusion defects. RESULTS: There was a similar 10-year survival between those with no or minimal CAD, nonobstructive CAD, and obstructive CAD (p = 0.6). Additionally, there was no difference in arrhythmia burden, including sustained ventricular tachycardias or frequent premature ventricular contractions (> 5% daily burden; p = 0.25). There was also no increase in mortality among those who had reversible perfusion defects >0% compared with those without, among subjects who underwent MPI (p = 0.14). On subgroup analysis, there was no increased risk in all-cause mortality with any specific coronary artery involvement, or with obstructive multivessel CAD (p = 0.89). CONCLUSION: Flecainide use is not associated with an increase in either all-cause mortality or ventricular arrhythmias in low-risk patients with stable nonobstructive CAD.

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.