A biomarker assay to risk-stratify patients with symptoms of respiratory tract infection.

BACKGROUND: Patients who present to an emergency department (ED) with respiratory symptoms are often conservatively triaged in favour of hospitalisation. We sought to determine if an inflammatory biomarker panel that identifies the host response better predicts hospitalisation in order to improve the precision of clinical decision making in the ED. METHODS: From April 2020 to March 2021, plasma samples of 641 patients with symptoms of respiratory illness were collected from EDs in an international multicentre study: Canada (n=310), Italy (n=131) and Brazil (n=200). Patients were followed prospectively for 28 days. Subgroup analysis was conducted on confirmed coronavirus disease 2019 (COVID-19) patients (n=245). An inflammatory profile was determined using a rapid, 50-min, biomarker panel (RALI-Dx (Rapid Acute Lung Injury Diagnostic)), which measures interleukin (IL)-6, IL-8, IL-10, soluble tumour necrosis factor receptor 1 (sTNFR1) and soluble triggering receptor expressed on myeloid cells 1 (sTREM1). RESULTS: RALI-Dx biomarkers were significantly elevated in patients who required hospitalisation across all three sites. A machine learning algorithm that was applied to predict hospitalisation using RALI-Dx biomarkers had a mean±sd area under the receiver operating characteristic curve of 76±6% (Canada), 84±4% (Italy) and 86±3% (Brazil). Model performance was 82±3% for COVID-19 patients and 87±7% for patients with a confirmed pneumonia diagnosis. CONCLUSIONS: The rapid diagnostic biomarker panel accurately identified the need for inpatient care in patients presenting with respiratory symptoms, including COVID-19. The RALI-Dx test is broadly and easily applicable across many jurisdictions, and represents an important diagnostic adjunct to advance ED decision-making protocols.

Lung Ultrasonography for the Diagnosis of SARS-CoV-2 Pneumonia in the Emergency Department.

STUDY OBJECTIVE: Accurate diagnostic testing to identify severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is critical. Although highly specific, SARS-CoV-2 reverse transcriptase-polymerase chain reaction (RT-PCR) has been shown in clinical practice to be affected by a noninsignificant proportion of false-negative results. This study seeks to explore whether the integration of lung ultrasonography with clinical evaluation is associated with increased sensitivity for the diagnosis of coronavirus disease 2019 pneumonia, and therefore may facilitate the identification of false-negative SARS-CoV-2 RT-PCR results. METHODS: This prospective cohort study enrolled consecutive adult patients with symptoms potentially related to SARS-CoV-2 infection who were admitted to the emergency department (ED) of an Italian academic hospital. Immediately after the initial assessment, a lung ultrasonographic evaluation was performed and the likelihood of SARS-CoV-2 infection, based on both clinical and lung ultrasonographic findings ("integrated" assessment), was recorded. RT-PCR SARS-CoV-2 detection was subsequently performed. RESULTS: We enrolled 228 patients; 107 (46.9%) had SARS-CoV-2 infection. Sensitivity and negative predictive value of the clinical-lung ultrasonographic integrated assessment were higher than first RT-PCR result (94.4% [95% confidence interval {CI} 88.2% to 97.9%] versus 80.4% [95% CI 71.6% to 87.4%] and 95% [95% CI 89.5% to 98.2%] versus 85.2% [95% CI 78.3% to 90.6%], respectively). Among the 142 patients who initially had negative RT-PCR results, 21 tested positive at a subsequent molecular test performed within 72 hours. All these false-negative cases were correctly identified by the integrated assessment. CONCLUSION: This study suggests that, in patients presenting to the ED with symptoms commonly associated with SARS-CoV-2 infection, the integration of lung ultrasonography with clinical evaluation has high sensitivity and specificity for coronavirus disease 2019 pneumonia and it may help to identify false-negative results occurring with RT-PCR.

Impact of platelet reactivity on 5-year clinical outcomes following percutaneous coronary intervention: a landmark analysis.

We investigated the impact of suboptimal platelet reactivity on clinical outcomes after percutaneous coronary intervention (PCI). We enrolled 500 patients with stable coronary artery disease undergoing elective PCI. Platelet reactivity was measured before PCI using the VerifyNow P2Y12 assay. Primary endpoint was the incidence of ischemic or bleeding events at 1 month and 5 years. Patients with high platelet reactivity (HPR) showed significantly higher rates of ischemic events both during the 1st month after PCI (HR 2.06, 95% CI 1.02-4.06), and beyond 1 month compared with patients without HPR (HR 1.73, 95% CI 1.02-2.95). Conversely, compared with patients without low platelet reactivity (LPR), patients with LPR presented significantly higher rates of bleeding only during the 1st month (HR 3.67, 95% CI 1.68-8.02). In conclusion, pre-procedural HPR is associated with ischemic events even beyond the 1st month after PCI. The association of LPR with bleeding events seems to be confined to the periprocedural period.

A Preclinical Translational Study of the Cardioprotective Effects of Plasma-Derived Alpha-1 Anti-trypsin in Acute Myocardial Infarction.

BACKGROUND: The area of myocardial infarction continues to expand for hours after reperfusion. The injured but viable myocardium may be salvaged if the signals leading to cell death are interrupted. Activation of the caspase-1 inflammasome in the heart shortly after ischemia-reperfusion contributes to the final infarct size. Plasma-derived α-1 anti-trypsin (AAT) has shown to inhibit inflammasome formation in vitro and in vivo. To explore the potential translational clinical value of AAT as a therapeutic, we conducted a series of preclinical experiments designed to simulate clinically relevant scenarios. METHODS: Adult male CD1 mice were used. The left anterior descending coronary artery was ligated for 30 or 75 minutes followed by reperfusion, to explore different severity of ischemic injury. Plasma-derived AAT (Prolastin C) was administered intraperitoneally after reperfusion, without pretreatment, exploring 3 different doses (60, 120, and 180 mg/kg). In a subgroup of mice, we administered Prolastin C with a delay of 30 minutes after reperfusion to simulate the clinical context of delayed administration, and we also used a model of permanent coronary artery ligation without reperfusion. Finally, we tested whether a single dose at reperfusion was sufficient to maintain a benefit in the longer term (7 days). Infarct size was measured by 3 different and independent methodologies: pathology, plasma levels of troponin I, and wall motion abnormalities at echocardiography. RESULTS: Prolastin C given at reperfusion after 30 minutes of ischemia provided a powerful reduction in infarct size (>50% reduction in all methodology used, all P < 0.01) without a clear dose-dependent response. Prolongation of ischemia to 75 minutes nor a delay in treatment by 30 minutes after reperfusion had any negative impact on Prolastin C effects. A single dose given at reperfusion was as effective as multiple daily doses. When given to the mouse without reperfusion, Prolastin C failed to reduce infarct size. CONCLUSIONS: Plasma-derived AAT (Prolastin C) given as an adjunct to reperfusion powerfully limits the final infarct size across a wide range of experiments in the mouse reproducing clinically relevant scenarios, such as variable duration of ischemia, delay in administration in the drug, and a large therapeutic index.

Diagnosis of acute aortic syndromes with ultrasound and d-dimer: the PROFUNDUS study.

BACKGROUND: In patients complaining common symptoms such as chest/abdominal/back pain or syncope, acute aortic syndromes (AAS) are rare underlying causes. AAS diagnosis requires urgent advanced aortic imaging (AAI), mostly computed tomography angiography. However, patient selection for AAI poses conflicting risks of misdiagnosis and overtesting. OBJECTIVES: We assessed the safety and efficiency of a diagnostic protocol integrating clinical data with point-of-care ultrasound (POCUS) and d-dimer (single/age-adjusted cutoff), to select patients for AAI. METHODS: This prospective study involved 12 Emergency Departments from 5 countries. POCUS findings were integrated with a guideline-compliant clinical score, to define the integrated pre-test probability (iPTP) of AAS. If iPTP was high, urgent AAI was requested. If iPTP was low and d-dimer was negative, AAS was ruled out. Patients were followed for 30 days, to adjudicate outcomes. RESULTS: Within 1979 enrolled patients, 176 (9 %) had an AAS. POCUS led to net reclassification improvement of 20 % (24 %/-4 % for events/non-events, P < 0.001) over clinical score alone. Median time to AAS diagnosis was 60 min if POCUS was positive vs 118 if negative (P = 0.042). Within 941 patients satisfying rule-out criteria, the 30-day incidence of AAS was 0 % (95 % CI, 0-0.41 %); without POCUS, 2 AAS were potentially missed. Protocol rule-out efficiency was 48 % (95 % CI, 46-50 %) and AAI was averted in 41 % of patients. Using age-adjusted d-dimer, rule-out efficiency was 54 % (difference 6 %, 95 % CI, 4-9 %, vs standard cutoff). CONCLUSIONS: The integrated algorithm allowed rapid triage of high-probability patients, while providing safe and efficient rule-out of AAS. Age-adjusted d-dimer maximized efficiency. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov, NCT04430400.

Impact of Endothelial Dysfunction on Long-Term Clinical Outcomes in Patients With Chronic Coronary Syndromes Treated With Second Generation Drug-Eluting Stent Implantation.

BACKGROUND: Studies investigating clinical outcomes of patients with or without endothelial disfunction (ED) treated with percutaneous coronary intervention (PCI) for stable coronary artery disease (CAD) using second generation drug eluting stents (DES) are lacking. METHODS: We prospectively collected data from 109 patients undergoing PCI with second generation DES due to stable CAD between December 2014 and September 2016. ED was evaluated evaluating the flow mediated dilation (FMD) at the brachial artery level and defined by an FMD < 7 %. Primary outcome were major adverse cardiovascular events (MACE), secondary outcomes were target vessel failure (TVR), myocardial infarction (MI) and all-cause death. RESULTS: Five-year follow-up was available in all patients. Median FMD didn't significantly differ between patients who experienced the outcome and those who didn't [no TVR vs. TVR: p = 0.358; no MI vs. MI: p = 0.157; no death vs. death: p = 0.355; no MACE vs. MACE: p = 0.805]. No association between ED and an increased risk for the primary outcome as well as for the secondary ones was evident [MACE: 17.0 % vs. 14.3 %, HR 0.87 (0.33-2.26), log rank p = 0.780; TVR: 9.4 % vs. 5.4 %, HR 0.53 (0.12-2.24), log rank p = 0.384; MI: 3.7 % vs. 8.9 %, HR 2.46 (0.47-12.76), log rank p = 0.265; death: 7.5 % vs. 3.6 %, HR 0.53 (0.09-2.90), log rank p = 0.458]. These findings were confirmed using a lower threshold of FMD to define ED and at one-year landmark analysis. CONCLUSIONS: ED is not associated with an increased risk of adverse events at long-term follow-up in a contemporary cohort of patients undergoing PCI with second generation DES.

Thrombopoietin participates in platelet activation in COVID-19 patients.

BACKGROUND: The pathogenesis of coronavirus disease 2019 (COVID-19) is characterized by enhanced platelet activation and diffuse hemostatic alterations, which may contribute to immunothrombosis/thromboinflammation and subsequent development of target-organ damage. Thrombopoietin (THPO), a growth factor essential to megakariocyte proliferation, is known to prime platelet activation and leukocyte-platelet interaction. In addition, THPO concentrations increase in several critical diseases, such as acute cardiac ischemia and sepsis, thus representing a potential diagnostic and prognostic biomarker. Furthermore, several data suggest that interleukin (IL)-6 is one of the most important inflammatory mediators involved in these phenomena, which led to explore the potential therapeutic role of IL-6 inhibitors. In this prospective cohort study, we aimed to study THPO and IL-6 concentrations in COVID-19 patients at the time of first clinical evaluation in the Emergency Department (ED), and to investigate their potential use as diagnostic and prognostic biomarkers. In addition, we sought to explore the role of THPO contained in plasma samples obtained from COVID-19 patients in priming in vitro platelet activation and leukocyte-platelet interaction. METHODS: We enrolled 66 patients presenting to the ED with symptoms suggestive of COVID-19, including 47 with confirmed COVID-19 and 19 in whom COVID-19 was excluded (Non-COVID-19 patients). As controls, we also recruited 18 healthy subjects. In vitro, we reproduced the effects of increased circulating THPO on platelet function by adding plasma from COVID-19 patients or controls to platelet-rich plasma or whole blood obtained by healthy donors, and we indirectly studied the effect of THPO on platelet activation by blocking its biological activity. FINDINGS: THPO levels were higher in COVID-19 patients than in both Non-COVID-19 patients and healthy subjects. Studying THPO as diagnostic marker for the diagnosis of COVID-19 by receiver-operating-characteristic (ROC) statistics, we found an area under the curve (AUC) of 0.73, with an optimal cut-off value of 42.60 pg/mL. IL-6 was higher in COVID-19 patients than in healthy subjects, but did not differ between COVID-19 and Non-COVID-19 patients. THPO concentrations measured at the time of diagnosis in the ED were also higher in COVID-19 patients subsequently developing a severe disease than in those with mild disease. Evaluating THPO as biomarker for severe COVID-19 using ROC analysis, we found an AUC of 0.71, with an optimal cut-off value of 57.11 pg/mL. IL-6 was also higher in severe than in mild COVID-19 patients, with an AUC for severe COVID-19 of 0.83 and an optimal cut-off value of 23 pg/ml. THPO concentrations correlated with those of IL-6 (r=0.2963; p=0.043), and decreased 24 h after the administration of tocilizumab, an IL-6 receptor blocking antibody, showing that the increase of THPO levels depends on IL-6-stimulated hepatic synthesis. In vitro, plasma obtained from COVID-19 patients, but not from healthy subjects, primed platelet aggregation and leukocyte-platelet binding, and these effects were reduced by inhibiting THPO activity. INTERPRETATION: Increased THPO may be proposed as an early biomarker for the diagnosis of COVID-19 and for the identification of patients at risk of developing critical illness. Elevated THPO may contribute to enhance platelet activation and leukocyte-platelet interaction in COVID-19 patients, thus potentially participating in immunothrombosis/thromboinflammation. FUNDING: This work was supported by Ministero dell'Università e della Ricerca Scientifica e Tecnologica (MURST) ex 60% to GM and EL.

Platelet reactivity and clinical outcomes following percutaneous coronary intervention in complex higher-risk patients.

AIMS: To investigate the levels of platelet reactivity and the impact of high platelet reactivity (HPR) on long-term clinical outcomes of complex higher-risk and indicated patients (CHIP) with stable coronary artery disease (CAD) treated with elective percutaneous coronary intervention (PCI). METHODS: We enrolled 500 patients undergoing elective PCI for stable CAD and treated with aspirin and clopidogrel. Patients were divided into four groups based on the presence of CHIP features and HPR. Primary endpoint was the occurrence of major adverse clinical events (MACE) at 5 years. RESULTS: The prevalence of HPR was significantly greater in the CHIP population rather than non-CHIP patients (39.9% vs 29.8%, P = 0.021). Patients with both CHIP features and HPR showed the highest estimates of MACE (22.1%, log-rank P = 0.047). At Cox proportional hazard analysis, the combination of CHIP features and HPR was an independent predictor of MACE (hazard ratio 2.57, 95% confidence interval 1.30-5.05, P = 0.006). CONCLUSION: Among patients with stable CAD undergoing elective PCI and treated with aspirin and clopidogrel, the combination of CHIP features and HPR identifies a cohort of patients with the highest risk of MACE at 5 years, who might benefit from more potent antiplatelet strategies.

Non-INvasive Functional and Anatomic vascular evaluation for the prediction of coronary artery disease: The NINFA study.

BACKGROUND: Endothelial function, as assessed with flow-mediated dilatation (FMD), and carotid intima-media thickness (IMT) correlate with the presence and extent of coronary artery disease (CAD). We investigated the incremental value of a combined evaluation of FMD and IMT in predicting the presence of CAD over traditional cardiovascular risk factors. METHODS: A total of 497 consecutive patients undergoing elective coronary angiography were enrolled in this study. Brachial artery FMD and ultrasound-based carotid IMT were evaluated prior to angiography. CAD was defined as the presence of a ≥ 50% stenosis in at least one coronary artery. SYNTAX score was also calculated. Patients were categorized based on the presence of FMD and IMT values below or above gender-specific median. RESULTS: Patients with both low FMD and high IMT presented the highest prevalence of CAD, number of diseased vessels, and SYNTAX score. At multivariate analysis, the combination of low FMD and high IMT was the strongest predictor of CAD (OR 3.63, 95% CI 2.19-6.02; p < .001). At ROC curve analysis, the addition of FMD and IMT to a model of traditional risk factors improved the predictive power for the presence of CAD (area under the curve [AUC] of risk factors model 0.715; AUC of risk factors + FMD + IMT 0.780; p < .001). The addition of FMD and IMT to the model of risk factors correctly reclassified 24.9% of patients. CONCLUSIONS: A combined evaluation of endothelial function and subclinical atherosclerosis at the carotid artery level improves the ability of traditional risk factors to identify patients with CAD.

Impact of Tourniquet Use on Systemic Inflammatory Parameters, Functional Physical Recovery, and Cardiovascular Outcomes of Patients Undergoing Knee Arthroplasty: A Case-Control Study.

The benefits of tourniquet use during orthopaedic surgery are controversial. We aim to investigate its effects on systemic inflammation, functional physical recovery, and cardiovascular complications of patients undergoing knee arthroplasty. We enrolled 129 consecutive patients (57 treated with tourniquet vs. 72 in the control group) undergoing total unilateral knee arthroplasty, followed by inpatient rehabilitation protocol at our institution. Blood samples were drawn in all patients at baseline and within 24 hours after surgery for complete blood cell count assessment. Neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were calculated as the ratio between the absolute number of neutrophil and platelets over the absolute number of lymphocytes, respectively. The numeric rating scale (NRS; 0-10) assessed the current pain, day after the surgery. All subjects underwent physical functional evaluation measured by the modified Barthel's index (MBI) at the end of the rehabilitation. We also recorded the incidence of major bleeding, typical angina, and occurrence of atrial fibrillation after surgery. In the overall population, a significant postprocedural increase in NLR and PLR was observed (p < 0.001). Baseline NLR and PLR were similar in patients with and without tourniquet (1.5 ± 0.8 vs. 1.95 ± 1.2, p = 0.081; 120 ± 42 vs. 131 ± 55, p = 0.240); however, patients treated with tourniquet showed significantly lower NLR at 24 hours (6.1 ± 3.6 vs. 8.1 ± 5.7, p = 0.043). NRS scores were significantly higher in the tourniquet group without compromising functional and physical recovery whereas no significant differences were appreciated in MBI scores between the two groups. Moreover, the rates of postoperative atrial fibrillation (1 [2%] vs. 9 [12%], p = 0.042) and major bleeding (2 [4%] vs. 11 [15%], p = 0.038) were significantly lower in the tourniquet group. Tourniquet seems a useful tool which is able to mitigate the inflammatory activation and prevent the occurrence of atrial fibrillation and major bleeding without altering functional physical recovery of patients undergoing total knee arthroplasty.

Interaction Between Diabetes Mellitus and Platelet Reactivity in Determining Long-Term Outcomes Following Percutaneous Coronary Intervention.

Diabetes mellitus (DM) is an independent predictor of adverse outcomes in patients with coronary artery disease (CAD). We investigated the interaction between DM and high platelet reactivity (HPR) in determining long-term clinical outcomes after percutaneous coronary intervention (PCI). We enrolled 500 patients who were divided based on the presence of DM and HPR. Primary endpoint was the occurrence of major adverse clinical events (MACE) at 5 years. Patients with both DM and HPR showed the highest estimates of MACE (37.9%, log-rank p < 0.001), all-cause death (15.5%, log-rank p = 0.022), and non-fatal myocardial infarction (25.9%, log-rank p < 0.001). At Cox proportional hazard analysis, the coexistence of DM and HPR was an independent predictor of MACE (HR 3.46, 95% CI 1.67-6.06, p < 0.001). Among patients with stable CAD undergoing elective PCI and treated with aspirin and clopidogrel, the combination of DM and HPR identifies a cohort of patients with the highest risk of MACE at 5 years.

Impact of Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio on 5-Year Clinical Outcomes of Patients with Stable Coronary Artery Disease Undergoing Elective Percutaneous Coronary Intervention.

The prognostic role of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in patients with stable coronary artery disease (CAD) is still unclear. We enrolled 500 patients undergoing elective percutaneous coronary intervention (PCI). Blood samples were drawn prior to PCI for NLR and PLR calculation. Major adverse clinical events (MACE), which included death, myocardial infarction (MI), and target vessel revascularization (TVR), were recorded up to 5 years. Patients in the higher tertile of NLR presented higher Kaplan-Meier estimates of MACE (26.0% vs. 16.9% in tertile 2 vs. 14.3% in tertile 1; p = 0.042) and death (12.0% vs 6.9% in tertile 2 vs. 4.6% in tertile 1; p = 0.040), whereas there were no significant differences in the estimates of MI and TVR. NLR in the higher tertile was an independent predictor of MACE (HR 1.65, 95% CI 1.07-2.55, p = 0.024). No significant difference was observed across tertiles of PLR. Unlike PLR, elevated pre-procedural NLR is associated with an increased risk of 5-year clinical adverse events.