Stratification of acute myocardial and endothelial cell injury, salvage index and final infarct size by systematic microRNA profiling in acute ST-elevation myocardial infarction.

AIM: Acute injury and subsequent remodelling responses to ST-segment elevation myocardial infarction (STEMI) are major determinants of clinical outcome. Current imaging and plasma biomarkers provide delayed readouts of myocardial injury and recovery. Here, we sought to systematically characterize all microRNAs (miRs) released during the acute phase of STEMI and relate miR release to magnetic resonance imaging (MRI) findings to predict acute and late responses to STEMI, from a single early blood sample. METHODS AND RESULTS: miRs were quantified in blood samples obtained from patients after primary PCI (PPCI) for STEMI. Cardiac MRI (cMRI) was performed to quantify myocardial edema, infarct size and salvage index. Regression models were constructed to predict these outcomes measures, which were then tested with a validation cohort. Transcoronary miR release was quantified from paired measurements of coronary artery and coronary sinus samples. A cell culture model was used to identify endothelial cell-derived miRs.A total of 72 patients undergoing PPCI for acute STEMI underwent miR analysis and cMRI. About >200 miRs were detectable in plasma after STEMI, from which 128 miRs were selected for quantification in all patients. Known myocardial miRs demonstrated a linear correlation with troponin release, and these increased across the transcoronary gradient. We identified novel miRs associated with microvascular injury and myocardial salvage. Regression models were constructed using a training cohort, then tested in a validation cohort, and predicted myocardial oedema, infarct size and salvage index. CONCLUSION: Analysis of miR release after STEMI identifies biomarkers that predict both acute and late outcomes after STEMI. A novel miR-based biomarker score enables the estimation of area at risk, late infarct size and salvage index from a single blood sample 6 hours after PPCI, providing a simple and rapid alternative to serial cMRI characterization of STEMI outcome.

The Relationship Between Cardiac Troponin in People Hospitalised for Exacerbation of COPD and Major Adverse Cardiac Events (MACE) and COPD Readmissions.

Background: No single biomarker currently risk stratifies chronic obstructive pulmonary disease (COPD) patients at the time of an exacerbation, though previous studies have suggested that patients with elevated troponin at exacerbation have worse outcomes. This study evaluated the relationship between peak cardiac troponin and subsequent major adverse cardiac events (MACE) including all-cause mortality and COPD hospital readmission, among patients admitted with COPD exacerbation. Methods: Data from five cross-regional hospitals in England were analysed using the National Institute of Health Research Health Informatics Collaborative (NIHR-HIC) acute coronary syndrome database (2008-2017). People hospitalised with a COPD exacerbation were included, and peak troponin levels were standardised relative to the 99th percentile (upper limit of normal). We used Cox Proportional Hazard models adjusting for age, sex, laboratory results and clinical risk factors, and implemented logarithmic transformation (base-10 logarithm). The primary outcome was risk of MACE within 90 days from peak troponin measurement. Secondary outcome was risk of COPD readmission within 90 days from peak troponin measurement. Results: There were 2487 patients included. Of these, 377 (15.2%) patients had a MACE event and 203 (8.2%) were readmitted within 90 days from peak troponin measurement. A total of 1107 (44.5%) patients had an elevated troponin level. Of 1107 patients with elevated troponin at exacerbation, 256 (22.8%) had a MACE event and 101 (9.0%) a COPD readmission within 90 days from peak troponin measurement. Patients with troponin above the upper limit of normal had a higher risk of MACE (adjusted HR 2.20, 95% CI 1.75-2.77) and COPD hospital readmission (adjusted HR 1.37, 95% CI 1.02-1.83) when compared with patients without elevated troponin. Conclusion: An elevated troponin level at the time of COPD exacerbation may be a useful tool for predicting MACE in COPD patients. The relationship between degree of troponin elevation and risk of future events is complex and requires further investigation.

Periprocedural antithrombotic strategies in acute coronary syndromes undergoing percutaneous coronary intervention: Have we discarded bivalirudin too soon?

BACKGROUND: Publication of the BRIGHT-4 trial results has restimulated discussion about the optimal periprocedural antithrombotic strategy for patients undergoing percutaneous coronary intervention (PCI) with acute coronary syndromes (ACS). It is possible that variation in the infusion duration, may contribute to observed differences in safety-efficacy profiles of bivalirudin in this clinical setting. METHODS: Up to December 2022, randomized controlled trials (RCTs) comparing bivalirudin (either administered peri-procedurally or accompanied by postprocedural infusion) and heparin, both with or without GPI, were searched and entered in a frequentist network meta-analysis. Co-primary endpoints were trial-defined major adverse composite events (MACE) and major bleeding. Incident rate ratios (IRR) and 95 % confidence intervals (CI) were estimated. RESULTS: 10 RCTs (N = 57,137 patients/month) were included. As compared to heparin, prolonged bivalirudin infusion resulted in lower rates of major bleeding (IRR 0.58, 95 % CI 0.36-0.91), but there was no differences in MACE rates between these strategies. With regard to NACE, prolonged bivalirudin infusion yielded lower risk (IRR 0.86, 95 % CI 0.77-0.96), whereas both bivalirudin and heparin increased risk when coupled with GPI (IRR 1.24, 95 % CI 1.01-1.51 and IRR 1.24, 95 % CI 1.06-1.44, respectively). Both these combination strategies also increased minor bleeding rates (IRR 1.49, 95 % CI 1.16-1.93 and IRR 1.58, 95 % CI 1.29-1.95, respectively, for bivalirudin and heparin). Results were consistent across several sensitivity analyses. CONCLUSION: In patients with ACS undergoing PCI, procedural bivalirudin administration followed by prolonged infusion results in lower major bleeding rates, but there does not appear to be a difference in observed MACE.

Routine cerebral embolic protection in transcatheter aortic valve implantation: rationale and design of the randomised British Heart Foundation PROTECT-TAVI trial.

Transcatheter aortic valve implantation (TAVI) is an established treatment for aortic stenosis. Cerebral embolic protection (CEP) devices may impact periprocedural stroke by capturing debris destined for the brain. However, there is a lack of high-quality randomised trial evidence supporting the use of CEP during TAVI. The British Heart Foundation (BHF) PROTECT-TAVI trial will address whether the routine use of CEP reduces the incidence of stroke in patients undergoing TAVI. BHF PROTECT-TAVI is a prospective, open-label, outcome-adjudicated, multicentre randomised controlled trial. The trial is open to all adult patients scheduled for TAVI at participating specialist cardiac centres across the United Kingdom who are able to receive the CEP device. The trial will recruit 7,730 participants. Participants will be randomised in a 1:1 ratio to undergo TAVI with CEP or TAVI without CEP (standard of care). The primary outcome is the incidence of stroke at 72 hours post-TAVI. Key secondary outcomes include the incidence of stroke and all-cause mortality up to 12 months post-TAVI, disability and cognitive outcomes, stroke severity, access site complications and a health economics analysis. The sample size of 7,730 participants has 80% power to detect a 33% relative risk reduction from a 3% incidence of the primary outcome in the controls. Trial recruitment commenced in October 2020. As of October 2022, 3,068 patients have been enrolled. BHF PROTECT-TAVI is designed to provide definitive evidence on the clinical efficacy and cost-effectiveness of using routine CEP with the SENTINEL device to reduce stroke in TAVI.

Neuropeptide-Y Levels in ST-Segment-Elevation Myocardial Infarction: Relationship With Coronary Microvascular Function, Heart Failure, and Mortality.

Background The sympathetic cotransmitter, neuropeptide Y (NPY), is released into the coronary sinus during ST-segment-elevation myocardial infarction and can constrict the coronary microvasculature. We sought to establish whether peripheral venous (PV) NPY levels, which are easy to obtain and measure, are associated with microvascular obstruction, myocardial recovery, and prognosis. Methods and Results NPY levels were measured immediately after primary percutaneous coronary intervention and compared with angiographic and cardiovascular magnetic resonance indexes of microvascular function. Patients were prospectively followed up for 6.4 (interquartile range, 4.1-8.0) years. PV (n=163) and coronary sinus (n=68) NPY levels were significantly correlated (r=0.92; P<0.001) and associated with multiple coronary and imaging parameters of microvascular function and infarct size (such as coronary flow reserve, acute myocardial edema, left ventricular ejection fraction, and late gadolinium enhancement 6 months later). We therefore assessed the prognostic value of PV NPY during follow-up, where 34 patients (20.7%) developed heart failure or died. Kaplan-Meier survival analysis demonstrated that high PV NPY levels (>21.4 pg/mL by binary recursive partitioning) were associated with increased incidence of heart failure and mortality (hazard ratio, 3.49 [95% CI, 1.65-7.4]; P<0.001). This relationship was maintained after adjustment for age, cardiovascular risk factors, and previous myocardial infarction. Conclusions Both PV and coronary sinus NPY levels correlate with microvascular function and infarct size after ST-segment-elevation myocardial infarction. PV NPY levels are associated with the subsequent development of heart failure or mortality and may therefore be a useful prognostic marker. Further research is required to validate these findings.

Comparison of Doppler Flow Velocity and Thermodilution Derived Indexes of Coronary Physiology.

OBJECTIVES: The aim of this study was to compare Doppler flow velocity and thermodilution-derived indexes and to determine the optimal thermodilution-based diagnostic thresholds for coronary flow reserve (CFR). BACKGROUND: The majority of clinical data and diagnostic thresholds for flow-based indexes are derived from Doppler measurements, and correspondence with thermodilution-derived indices remain unclear. METHODS: An international multicenter registry was conducted among patients who had coronary flow measurements using both Doppler and thermodilution techniques in the same vessel and during the same procedure. RESULTS: Physiological data from 250 vessels (in 149 patients) were included in the study. A modest correlation was found between thermodilution-derived CFR (CFRthermo) and Doppler-derived CFR (CFRDoppler) (r2 = 0.36; P < 0.0001). CFRthermo overestimated CFRDoppler (mean 2.59 ± 1.46 vs 2.05 ± 0.89; P < 0.0001; mean bias 0.59 ± 1.24 by Bland-Altman analysis), the relationship being described by the equation CFRthermo = 1.04 × CFRDoppler + 0.50. The commonly used dichotomous CFRthermo threshold of 2.0 had poor sensitivity at predicting a CFRDoppler value <2.5. The optimal CFRthermo threshold was 2.5 (sensitivity 75.54%, specificity 81.25%). There was only a weak correlation between hyperemic microvascular resistance and index of microvascular resistance (r2 = 0.19; P < 0.0001), due largely to variation in the measurement of flow by each modality. Forty-four percent of patients were discordantly classified as having abnormal microvascular resistance by hyperemic microvascular resistance (≥2.5 mm Hg · cm-1 · s) and index of microvascular resistance (≥25). CONCLUSIONS: CFR calculated by thermodilution overestimates Doppler-derived CFR, while both parameters show modest correlation. The commonly used CFRthermo threshold of 2.0 has poor sensitivity for identifying vessels with diminished CFR, but using the same binary diagnostic threshold as for Doppler (<2.5) yields reasonable diagnostic accuracy. There was only a weak correlation between microvascular resistance indexes assessed by the 2 modalities.

Invasive coronary physiology in patients with angina and non-obstructive coronary artery disease: a consensus document from the coronary microvascular dysfunction workstream of the British Heart Foundation/National Institute for Health Research Partnership.

Nearly half of all patients with angina have non-obstructive coronary artery disease (ANOCA); this is an umbrella term comprising heterogeneous vascular disorders, each with disparate pathophysiology and prognosis. Approximately two-thirds of patients with ANOCA have coronary microvascular disease (CMD). CMD can be secondary to architectural changes within the microcirculation or secondary to vasomotor dysfunction. An inability of the coronary vasculature to augment blood flow in response to heightened myocardial demand is defined as an impaired coronary flow reserve (CFR), which can be measured non-invasively, using imaging, or invasively during cardiac catheterisation. Impaired CFR is associated with myocardial ischaemia and adverse cardiovascular outcomes.The CMD workstream is part of the cardiovascular partnership between the British Heart Foundation and The National Institute for Health Research in the UK and comprises specialist cardiac centres with expertise in coronary physiology assessment. This document outlines the two main modalities (thermodilution and Doppler techniques) for estimation of coronary flow, vasomotor testing using acetylcholine, and outlines a standard operating procedure that could be considered for adoption by national networks. Accurate and timely disease characterisation of patients with ANOCA will enable clinicians to tailor therapy according to their patients' coronary physiology. This has been shown to improve patients' quality of life and may lead to improved cardiovascular outcomes in the long term.

Risk of infective endocarditis after surgical and transcatheter aortic valve replacement.

OBJECTIVE: To define the incidence and risk factors for infective endocarditis (IE) following surgical aortic valve replacement (SAVR) and transcatheter aortic valve implantation (TAVI). METHODS: All patients who underwent first SAVR or TAVI in England between 2007 and 2016 were identified from the NICOR databases. Hospital admissions with a primary diagnosis of IE were identified by linkage with the NHS Hospital Episode Statistics database. Approval was obtained from the NHS Research Ethics Committee. RESULTS: 2057 of 91 962 patients undergoing SAVR developed IE over a median follow-up of 53.9 months-an overall incidence of 4.81 [95% CI 4.61 to 5.03] per 1000 person-years. Correspondingly, 140 of 14 195 patients undergoing TAVI developed IE over a median follow-up of 24.5 months-an overall incidence of 3.57 [95% CI 3.00 to 4.21] per 1000 person-years. The cumulative incidence of IE at 60 months was higher after SAVR than after TAVI (2.4% [95% CI 2.3 to 2.5] vs 1.5% [95% CI 1.3 to 1.8], HR 1.60, p<0.001). Across the entire cohort, SAVR remained an independent predictor of IE after multivariable adjustment. Risk factors for IE included younger age, male sex, atrial fibrillation, and dialysis. CONCLUSIONS: IE is a rare complication of SAVR and TAVI. In our population, the incidence of IE was higher after SAVR than after TAVI.

Effect of remote ischaemic conditioning on infarct size and remodelling in ST-segment elevation myocardial infarction patients: the CONDI-2/ERIC-PPCI CMR substudy.

The effect of limb remote ischaemic conditioning (RIC) on myocardial infarct (MI) size and left ventricular ejection fraction (LVEF) was investigated in a pre-planned cardiovascular magnetic resonance (CMR) substudy of the CONDI-2/ERIC-PPCI trial. This single-blind multi-centre trial (7 sites in UK and Denmark) included 169 ST-segment elevation myocardial infarction (STEMI) patients who were already randomised to either control (n = 89) or limb RIC (n = 80) (4 × 5 min cycles of arm cuff inflations/deflations) prior to primary percutaneous coronary intervention. CMR was performed acutely and at 6 months. The primary endpoint was MI size on the 6 month CMR scan, expressed as median and interquartile range. In 110 patients with 6-month CMR data, limb RIC did not reduce MI size [RIC: 13.0 (5.1-17.1)% of LV mass; control: 11.1 (7.0-17.8)% of LV mass, P = 0.39], or LVEF, when compared to control. In 162 patients with acute CMR data, limb RIC had no effect on acute MI size, microvascular obstruction and LVEF when compared to control. In a subgroup of anterior STEMI patients, RIC was associated with lower incidence of microvascular obstruction and higher LVEF on the acute scan when compared with control, but this was not associated with an improvement in LVEF at 6 months. In summary, in this pre-planned CMR substudy of the CONDI-2/ERIC-PPCI trial, there was no evidence that limb RIC reduced MI size or improved LVEF at 6 months by CMR, findings which are consistent with the neutral effects of limb RIC on clinical outcomes reported in the main CONDI-2/ERIC-PPCI trial.

Long-Term Clinical Outcomes in Patients With an Acute ST-Segment-Elevation Myocardial Infarction Stratified by Angiography-Derived Index of Microcirculatory Resistance.

Aims: Despite the prognostic value of coronary microvascular dysfunction (CMD) in patients with ST-segment-elevation myocardial infarction (STEMI), its assessment with pressure-wire-based methods remains limited due to cost, technical and procedural complexities. The non-hyperaemic angiography-derived index of microcirculatory resistance (NH IMRangio) has been shown to reliably predict microvascular injury in patients with STEMI. We investigated the prognostic potential of NH IMRangio as a pressure-wire and adenosine-free tool. Methods and Results: NH IMRangio was retrospectively derived on the infarct-related artery at completion of primary percutaneous coronary intervention (pPCI) in 262 prospectively recruited STEMI patients. Invasive pressure-wire-based assessment of the index of microcirculatory resistance (IMR) was performed. The combination of all-cause mortality, resuscitated cardiac arrest and new heart failure was the primary endpoint. NH IMRangio showed good diagnostic performance in identifying CMD (IMR > 40U); AUC 0.78 (95%CI: 0.72-0.84, p < 0.0001) with an optimal cut-off at 43U. The primary endpoint occurred in 38 (16%) patients at a median follow-up of 4.2 (2.0-6.5) years. On survival analysis, NH IMRangio > 43U (log-rank test, p < 0.001) was equivalent to an IMR > 40U(log-rank test, p = 0.02) in predicting the primary endpoint (hazard ratio comparison p = 0.91). NH IMRangio > 43U was an independent predictor of the primary endpoint (adjusted HR 2.13, 95% CI: 1.01-4.48, p = 0.047). Conclusion: NH IMRangio is prognostically equivalent to invasively measured IMR and can be a feasible alternative to IMR for risk stratification in patients presenting with STEMI.

Procedural Mortality With Transcatheter Aortic Valve Replacement - Balloon Inflation is Associated With Increased Risk.

OBJECTIVES: To assess the impact of balloon use for predilation, valve implantation, or postdilation on in-hospital mortality among patients undergoing transcatheter aortic valve replacement (TAVR). BACKGROUND: TAVR utilizes self-expanding, mechanically expanding, or balloon-expandable valves. Balloon inflation is inherent to deployment of balloon-expandable valves. Balloons may additionally be used with all valve types for pre- and postdilation. The relationships between valve mechanism, balloon use, and in-hospital mortality are not fully characterized. METHODS: Prospective data were collected on 4063 patients undergoing TAVR for aortic stenosis at 4 high-volume centers in the United Kingdom. In-hospital mortality was analyzed according to valve expansion mechanism, use of balloons for pre- and postdilation, and specific cause of death. RESULTS: Mean patient age was 83 ± 8 years. Implanted valves were self expanding (n = 2241; 55%), mechanically expanding (n = 1092; 27%), or balloon expandable (n = 727; 18%). In-hospital death occurred in 66 cases (1.6%). Thirty-six deaths (54.5%) were classified as implantation-related mortalities, with rates of 0.8%, 0.5%, and 1.7% (P=.04) among self-expanding, mechanically expanding, and balloon-expandable technologies, respectively. Patients who underwent balloon inflation at any stage of their procedure (n = 2556; 63%) had significantly higher implantation-related mortality than those who did not (1.3% vs 0.3%, respectively; P<.01). Balloon-expandable valve procedures were associated with significantly higher all-cause mortality (2.6% vs 1.4%; P=.02) and implantation-related mortality (1.7% vs 0.7%; P=.02) than non-balloon-expandable valve procedures. Balloon-related complications accounted for 18 cases (26%) of total in-hospital mortality, including all 12 cases (17.4%) of annular rupture and 5 cases (7.2%) of coronary occlusion. CONCLUSIONS: Balloon use for predilation, valve implantation, or postdilation was associated with an increased mortality risk. Balloon-related complications were the largest contributor to in-hospital mortality, comprising all cases of annular rupture and the majority of coronary occlusion cases.

Sixty-day consequences of COVID-19 in patients discharged from hospital: an electronic health records study.

Data on patients discharged following COVID-19 hospitalization is scarce. We conducted an electronic health records study of community-acquired COVID-19 patients discharged between 15 March and 14 July 2020 from hospitals in Oxfordshire, UK. Of 403 discharged patients, 114 (28%) were readmitted or died within 60 days (incidence rate 18/100 person-months). Rates of readmission or death were twice as high among those ≥ 65 years as those < 65 years [standardized rate ratio: 2.21 (95% CI: 1.45-3.56)] and among women than men [2.25 (1.05-4.18)]. These findings suggest important sex differences in 60-day outcomes following COVID-19 hospitalization that have not previously been well described.

EAPCI Core Curriculum for Percutaneous Cardiovascular Interventions (2020): Committee for Education and Training European Association of Percutaneous Cardiovascular Interventions (EAPCI). A branch of the European Society of Cardiology.

The proposed 2020 Core Curriculum for Percutaneous Cardiovascular Interventions aims to provide an updated European consensus that defines the level of experience and knowledge in the field of percutaneous cardiovascular intervention (PCI). It promotes homogenous education and training programmes among countries, and is the cornerstone of the new EAPCI certification, designed to support the recognition of competencies at the European level and the free movement of certified specialists in the European Community. It is based on a thorough review of the ESC guidelines and of the EAPCI textbook on percutaneous interventional cardiovascular medicine. The structure of the current core curriculum evolved from previous EAPCI core curricula and from the "2013 core curriculum of the general cardiologist" to follow the current ESC recommendations for core curricula. In most subject areas, there was a wide - if not unanimous - consensus among the task force members on the training required for the interventional cardiologist of the future. The document recommends that acquisition of competence in interventional cardiology requires at least two years of postgraduate training, in addition to four years devoted to cardiology. The first part of the curriculum covers general aspects of training and is followed by a comprehensive description of the specific components in 54 chapters. Each of the chapters includes statements of the objectives, and is further subdivided into the required knowledge, skills, behaviours, and attitudes.

Pressure-bounded coronary flow reserve to assess the extent of microvascular dysfunction in patients with ST-elevation acute myocardial infarction.

AIMS: Assessment of microvascular function in patients with ST-elevation acute myocardial infarction (STEMI) may be useful to determine treatment strategy. The possible role of pressure-bounded coronary flow reserve (pb-CFR) in this setting has not been determined. In this study we aimed to compare pb-CFR with thermodilution-derived physiology including the index of microcirculatory resistance (IMR) and CFRthermo in a consecutive series of patients enrolled in the OxAMI study. Moreover, we aimed to assess the presence of microvascular obstruction (MVO) and myocardial injury on cardiovascular magnetic resonance (CMR) imaging performed at 48 hours and six months in STEMI patients stratified according to pb-CFR. METHODS AND RESULTS: Thermodilution-pressure-wire assessment of the infarct-related artery was performed in 148 STEMI patients before stenting and/or at completion of primary percutaneous coronary intervention (PPCI). The extent of the myocardial injury was assessed with CMR imaging at 48 hours and six months after STEMI. Post-PPCI pb-CFR was impaired (<2) and normal (>2) in 69.9% and 9.0% of the cases, respectively. In the remaining 21.1% of the patients, pb-CFR was "indeterminate". In this cohort, pb-CFR correlated poorly with thermodilution-derived coronary flow reserve (k=0.03, p=0.39). The IMR was significantly different across the pb-CFR subgroups. Similarly, significant differences were observed in MVO, myocardium area at risk and 48-hour infarct size (IS). A trend towards lower six-month IS was observed in patients with high (>2) post-PPCI pb-CFR. Nevertheless, pb-CFR was inferior to IMR in predicting MVO and the extent of IS. CONCLUSIONS: Pb-CFR can identify microvascular dysfunction in patients after STEMI. It provided superior diagnostic performance compared to thermodilution-derived CFR in predicting MVO. However, IMR was superior to both pb-CFR and thermodilution-derived CFR and, consequently, IMR was the most accurate in predicting all of the studied CMR endpoints of myocardial injury after PPCI.

Effect of remote ischaemic conditioning on platelet reactivity and endogenous fibrinolysis in ST-elevation myocardial infarction: a substudy of the CONDI-2/ERIC-PPCI randomized controlled trial.

AIMS: Remote ischaemic conditioning (RIC) has been shown to reduce myocardial infarct size in animal models of myocardial infarction. Platelet thrombus formation is a critical determinant of outcome in ST-segment elevation myocardial infarction (STEMI). Whether the beneficial effects of RIC are related to thrombotic parameters is unclear. METHODS AND RESULTS: In a substudy of the Effect of Remote Ischaemic Conditioning on clinical outcomes in STEMI patients undergoing Primary Percutaneous Coronary Intervention (ERIC-PPCI) trial, we assessed the effect of RIC on thrombotic status. Patients presenting with STEMI were randomized to immediate RIC consisting of an automated autoRIC™ cuff on the upper arm inflated to 200 mmHg for 5 min and deflated for 5 min for four cycles (n = 53) or sham (n = 47). Venous blood was tested at presentation, discharge (48 h) and 6-8 weeks, to assess platelet reactivity, coagulation, and endogenous fibrinolysis using the Global Thrombosis Test and thromboelastography. Baseline thrombotic status was similar in the two groups. At discharge, there was some evidence that the time to in vitro thrombotic occlusion under high shear stress was longer with RIC compared to sham (454 ± 105 s vs. 403 ± 105 s; mean difference 50.1 s; 95% confidence interval 93.7-6.4, P = 0.025), but this was no longer apparent at 6-8 weeks. There was no difference in clot formation or endogenous fibrinolysis between the study arms at any time point. CONCLUSION: RIC may reduce platelet reactivity in the first 48 h post-STEMI. Further research is needed to delineate mechanisms through which RIC may reduce platelet reactivity, and whether it may improve outcomes in patients with persistent high on-treatment platelet reactivity.

Safety and Operational Efficiency of Restructuring and Redeploying a Transcatheter Aortic Valve Replacement Service During the COVID-19 Pandemic: The Oxford Experience.

BACKGROUND: The risk of nosocomial COVID-19 infection for vulnerable aortic stenosis patients and intensive care resource utilization has led to cardiac surgery deferral. Untreated severe symptomatic aortic stenosis has a dismal prognosis. TAVR offers an attractive alternative to surgery as it is not reliant on intensive care resources. We set out to explore the safety and operational efficiency of restructuring a TAVR service and redeploying it to a new non-surgical site during the COVID-19 pandemic. METHODS: The institutional prospective service database was retrospectively interrogated for the first 50 consecutive elective TAVR cases prior to and after our institution's operational adaptations for the COVID-19 pandemic. Our endpoints were VARC-2 defined procedural complications, 30-day mortality or re-admission and service efficiency metrics. RESULTS: The profile of patients undergoing TAVR during the pandemic was similar to patients undergoing TAVR prior to the pandemic with the exception of a lower mean age (79 vs 82 years, p < 0.01) and median EuroScore II (3.1% vs 4.6%, p = 0.01). The service restructuring and redeployment contributed to the pandemic-mandated operational efficiency with a reduction in the distribution of pre-admission hospital visits (3 vs 3 visits, p < 0.001) and the time taken from TAVR clinic to procedure (26 vs 77 days, p < 0.0001) when compared to the pre-COVID-19 service. No statistically significant difference was noted in peri-procedural complications and 30-day outcomes, while post-operative length of stay was significantly reduced (2 vs 3 days, p < 0.0001) when compared to pre-COVID-19 practice. CONCLUSIONS: TAVR service restructuring and redeployment to align with pandemic-mandated healthcare resource rationalization is safe and feasible.