Expanded genetic testing in familial hypercholesterolemia-A single center's experience.

Objective: Assess the yield of genetic testing for pathogenic variants in ABCG5, ABCG8, LIPA, and APOE in individuals with personal and family histories suggestive of familial hypercholesterolemia. Methods: Retrospective review of patients seen in the Advanced Lipid Disorders Clinic at Johns Hopkins. Results: In the lipid clinic at a single center during the years 2015-2023, 607 patients underwent genetic testing for familial hypercholesterolemia, of which 263 underwent the expanded genetic testing for sitosterolemia. Eighty-eight patients had genetic testing which included APOE, and 22 patients had testing which included LIPA. Among these, one patient was identified to have a pathogenic variant in APOE and another patient with a pathogenic variant in ABCG5 (0.7 % yield). The frequency of a positive result was double that of a variant of uncertain significance. Conclusion: These data suggest in rare cases expanded testing can provide answers for patients and families with a minimal likelihood of a variant of uncertain significance.

Homocysteine modifies the association of coronary stenosis and HIV infection in an inner city African American population.

BACKGROUND AND AIMS: People with HIV (PWH) whose disease is controlled on anti-retroviral regimens remain at an increased risk for coronary artery disease (CAD). Traditional cardiovascular risk factors do not fully explain the residual risk in PWH suggesting contributions from nontraditional factors. Homocysteine (Hcy) may be one of these as prior work in adults without HIV demonstrate that Hcy may impair endothelial function by decreasing the availability of nitric oxide, promoting the development of atherosclerosis. In addition, plasma Hcy levels are higher in PWH than in individuals living without HIV. The aim of this study was to investigate whether Hcy levels influence the association between HIV and coronary stenosis in an inner city African American population. METHODS: African Americans from the Heart Study in Baltimore, with and without HIV, recruited from inner-city Baltimore between June 2004 and February 2015, were included in this analysis. Participants underwent coronary CT angiography to evaluate the presence of coronary stenosis, defined as luminal stenosis >10%. Hcy was measured from stored serum samples. RESULTS: In this analysis, the median [IQR] age of the 664 participants was 56 [50-66] years; 68.1% were living with HIV and 43.1% were women. Elevated Hcy (>15 µmol/L) was more prevalent in those with coronary stenosis (23.3%, 95% CI: 18.4%-28.2%) than in those without coronary stenosis (13.1%, 95% CI: 9.7%-16.5%) (p = 0.0007), and HIV was associated with coronary stenosis in those participants with an elevated Hcy (Prevalence Ratio: 1.94, 95% CI: 1.04-3.64, p = 0.0038) and not in those with a Hcy ≤15 µmol/L (Prevalence Ratio: 1.02, 95% CI: 0.83-1.25, p = 0.87). CONCLUSIONS: Our data suggest an association between elevated Hcy levels (>15 µmol/L) and the prevalence of coronary stenosis in PWH from this inner city African American population.

Recent advances in cardiovascular risk assessment: The added value of non-invasive anatomic imaging.

In 2022, multiple original research studies were conducted highlighting the utility of coronary artery calcium (CAC) imaging in young individuals and provided further evidence for the role of CAC to improve atherosclerotic cardiovascular disease (ASCVD) risk assessment. Mean calcium density was shown to be a more reliable predictor than peak density in risk assessment. Additionally, in light of the ACC/AHA/Multispecialty Chest Pain Guideline's recent elevation of coronary computed tomography angiography (CCTA) to a Class I (level of evidence A) recommendation as an index diagnostic test for acute or stable chest pain, several studies support the utility of CCTA and guided future directions. This review summarizes recent studies that highlight the role of non-invasive imaging in enhancing ASCVD risk assessment across different populations.

LP(a): Structure, Genetics, Associated Cardiovascular Risk, and Emerging Therapeutics.

Lipoprotein(a) [Lp(a)] is a molecule bound to apolipoprotein(a) with some similarity to low-density lipoprotein cholesterol (LDL-C), which has been found to be a risk factor for cardiovascular disease (CVD). Lp(a) appears to induce inflammation, atherogenesis, and thrombosis. Approximately 20% of the world's population has increased Lp(a) levels, determined predominantly by genetics. Current clinical practices for the management of dyslipidemia are ineffective in lowering Lp(a) levels. Evolving RNA-based therapeutics, such as the antisense oligonucleotide pelacarsen and small interfering RNA olpasiran, have shown promising results in reducing Lp(a) levels. Phase III pivotal cardiovascular outcome trials [Lp(a)HORIZON and OCEAN(a)] are ongoing to evaluate their efficacy in secondary prevention of major cardiovascular events in patients with elevated Lp(a). The future of cardiovascular residual risk reduction may transition to a personalized approach where further lowering of either LDL-C, triglycerides, or Lp(a) is selected after high-intensity statin therapy based on the individual risk profile and preferences of each patient.

Early Initiation of PCSK9 Inhibitor Therapy Versus Placebo in Patients With Acute Coronary Syndrome: A Systematic Review and Meta-Analysis.

In patients with stable atherosclerotic cardiovascular disease, proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9is) have shown a 50% to 60% reduction in low-density lipoprotein cholesterol (LDL-C) from baseline when added to high-intensity statin therapy. However, less is known about the impact of PCSK9is in the setting of an acute coronary syndrome (ACS). Therefore, we performed a systematic review and meta-analysis comparing PCSK9is with placebo in the setting of ACS added to guideline-directed high-intensity or maximally tolerated statin therapy. We included randomized controlled trials with initiation of a PCSK9i or placebo within 1 week of presentation or percutaneous coronary intervention for ACS. PubMed, EMBASE, and Cochrane Central were searched. This study followed the Cochrane and Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) recommendations. A total of 6 randomized controlled trials were included, with a total of 996 patients, of whom 503 (50.5%) received PCSK9is. The mean follow-up ranged from 4 to 52 weeks. The LDL-C (mean difference [MD] -44.0 mg/100 ml, CI -54.3 to -33.8, p <0.001) and lipoprotein (a) levels (MD -24.0 nmol/L, confidence interval [CI] -43.0 to -4.9, p = 0.01) were significantly lower at follow-up with PCSK9is. Similarly, the total cholesterol (MD -49.2 mg/100 ml, CI -59.0 to -39.3), triglycerides (MD -19.0 mg/100 ml, CI -29.9 to -8.2), and apolipoprotein B (MD -33.3 mg/100 ml, CI -44.4 to -22.1) were significantly reduced with PCSK9is. In conclusion, in patients with ACS, early initiation of PCSK9i added to statin significantly reduces LDL-C and lipoprotein (a) levels compared with placebo. Whether the differences in these atherogenic lipoproteins translate into a reduction in clinical end points is yet to be determined.

Coronary artery endothelial function and aging in people with HIV and HIV-negative individuals.

Coronary artery disease (CAD) is a common comorbidity in people with human immunodeficiency virus (HIV) (PWH) and impaired coronary endothelial function (CEF) plays a central role in the pathogenesis of CAD. Age-related impaired CEF among PWH, however, is not well characterized. We investigated the association between CEF and age in males and females with and without HIV using 3-T magnetic resonance imaging (MRI). We measured the changes in coronary cross-sectional area (CSA) and coronary blood flow during isometric handgrip exercise (IHE), an established endothelial-dependent stressor with smaller increases in CSA and coronary blood flow indicative of impaired CEF. We included 106 PWH and 82 individuals without HIV. Differences in demographic and clinical characteristics between PWH and individuals without HIV were explored using Pearson's χ2 test for categorical variables and Welch's t test for continuous variables. Linear regression models were used to examine the association between CEF and age. CEF was significantly lower in PWH as compared with individuals without HIV. Coronary endothelial dysfunction was also present at younger ages in PWH than in the individuals without HIV and there were significant differences in CEF between the PWH and individuals without HIV across age groups. Among the individuals without HIV, the percent changes in CSA were inversely related to age in unadjusted and adjusted models. There was no significant association between CEF and age in PWH. To the best of our knowledge, this is the first study to examine the relationship between age and CEF in PWH, and our results suggest that factors other than age significantly impair CEF in PWH across the life span.NEW & NOTEWORTHY This is the first study to examine the relationship between age and coronary endothelial function (CEF) in people with human immunodeficiency virus (HIV) (PWH). CEF was assessed using magnetic resonance imaging (MRI) in people with and without HIV. Although age and CEF were significantly inversely related in individuals without HIV, there was no association between age and CEF in PWH.

Platelet activation and endothelial dysfunction biomarkers in acute coronary syndrome: the impact of PCSK9 inhibition.

AIMS: Platelet activation and endothelial dysfunction contribute to adverse outcomes in patients with acute coronary syndromes (ACS). The goals of this study were to assess the impact of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition on markers of platelet activation and endothelial dysfunction in ACS patients and the interaction among PCSK9, platelets, and endothelial cells (ECs) on left internal mammary artery (LIMA) vascular endothelium using specimens obtained during coronary artery bypass surgery (CABG). METHODS AND RESULTS: Acute coronary syndromes patients enrolled in the Evolocumab in ACS trials were randomized to placebo or a single dose of 420 mg evolocumab within 24 h of hospitalization. Serum samples for analysis of platelet factor 4 (PF4) and P-selectin, markers of platelet activation, and von Willebrand factor (vWF), a marker of endothelial dysfunction, were obtained at baseline and 30 days. Additionally, LIMA segments obtained during CABG from patients who were and were not receiving evolocumab were immunostained with PCSK9; CD61, a platelet-specific marker; and CD31, an endothelial cell-specific marker. Forty-six participants were randomized to placebo or to evolocumab. Controlling for baseline levels, PF4 and vWF were significantly lower in the evolocumab, than in the placebo, group at 30 days. Immunostaining of LIMA specimens from twelve participants undergoing CABG revealed colocalization of PCSK9, CD61, and CD31 at the vascular endothelium. Administration of evolocumab was associated with decreased overlap of PCSK9, CD61, and CD31. CONCLUSIONS: Proprotein Convertase Subtilisin/Kexin 9 inhibition decreases markers of platelet activation and endothelial dysfunction in ACS patients. PCSK9 is associated with platelets and vascular ECs in LIMA segments and PCSK9 inhibition decreases that interaction.

Novel Diagnostic Imaging Approach for Patients With Spontaneous Coronary Artery Dissection: The Utility of 18 F-FDG PET Imaging.

ABSTRACT: Spontaneous coronary artery dissection (SCAD) is an underdiagnosed etiology of acute coronary syndrome in women. Accurate diagnosis remains challenging but is imperative for treatment and prevention. We show here the utility of 18 F-FDG PET imaging in SCAD diagnosis. We present 1 representative case of 4 women with suspected SCAD on coronary angiography from the EVACS (Evolocumab in Acute Coronary Syndromes) clinical trial. 18 F-FDG PET imaging showed acute inflammation in the distribution of the suspected dissected coronary artery identified on angiography. Localized myocardial inflammation identified on 18 F-FDG PET imaging can aid in diagnosing SCAD suspected on coronary angiography.

Contemporary patterns of lipoprotein(a) testing and associated clinical care and outcomes.

Objective: Elevated lipoprotein(a) [Lp(a)] is associated with atherosclerotic cardiovascular disease, yet little is known about Lp(a) testing patterns in real-world practice. The objective of this analysis was to determine how Lp(a) testing is used in clinical practice in comparison with low density lipoprotein cholesterol (LDL-C) testing alone, and to determine whether elevated Lp(a) level is associated with subsequent initiation of lipid-lowering therapy (LLT) and incident cardiovascular (CV) events. Methods: This is an observational cohort study, based on lab tests administered between Jan 1, 2015 and Dec 31, 2019. We used electronic health record (EHR) data from 11 United States health systems participating in the National Patient-Centered Clinical Research Network (PCORnet). We created two cohorts for comparison: 1) the Lp(a) cohort, of adults with an Lp(a) test and 2) the LDL-C cohort, of 4:1 date- and site-matched adults with an LDL-C test, but no Lp(a) test. The primary exposure was the presence of an Lp(a) or LDL-C test result. In the Lp(a) cohort, we used logistic regression to assess the relationship between Lp(a) results in mass units (< 50, 50-100, and > 100mg/dL) and molar units (<125, 125-250, > 250nmol/L) and initiation of LLT within 3 months. We used multivariable adjusted Cox proportional hazards regression to evaluate these Lp(a) levels and time to composite CV hospitalization, including hospitalization for myocardial infarction, revascularization and ischemic stroke. Results: Overall, 20,551 patients had Lp(a) test results and 2,584,773 patients had LDL-C test results (82,204 included in the matched LDL-C cohort). Compared with the LDL-C cohort, the Lp(a) cohort more frequently had prevalent ASCVD (24.3% vs. 8.5%) and multiple prior CV events (8.6% vs. 2.6%). Elevated Lp(a) was associated with greater odds of subsequent LLT initiation. Elevated Lp(a) reported in mass units was also associated with subsequent composite CV hospitalization [aHR (95% CI): Lp(a) 50-100mg/dL 1.25 (1.02-1.53), p<0.03, Lp(a) > 100mg/dL 1.23 (1.08-1.40), p<0.01]. Conclusion: Lp(a) testing is relatively infrequent in health systems across the U.S. As new therapies for Lp(a) emerge, improved patient and provider education is needed to increase awareness of the utility of this risk marker.

Lipoprotein(a) concentrations in acute myocardial infarction patients are not indicative of levels at six month follow-up.

Aims: Lipoprotein(a) [Lp(a)] levels are generally constant throughout an individual's lifetime, and current guidelines recommend that a single measurement is sufficient to assess the risk of coronary artery disease (CAD). However, it is unclear whether a single measurement of Lp(a) in individuals with acute myocardial infarction (MI) is indicative of the Lp(a) level six months following the event. Methods and results: Lp(a) levels were obtained from individuals with non-ST-elevation myocardial infarction (NSTEMI) or ST-elevation myocardial infarction (STEMI) (n = 99) within 24 h of hospital admission and after six months, who were enrolled in two randomized trials of evolocumab and placebo, and in individuals with NSTEMI or STEMI (n = 9) who enrolled in a small observation arm of the two protocols and did not receive study drug, but whose levels were obtained at the same time points. Median Lp(a) levels increased from 53.5 nmol/L (19, 165) during hospital admission to 58.0 nmol/L (14.8, 176.8) six months after the acute infarction (P = 0.02). Subgroup analysis demonstrated no difference in the baseline, six-month, or change between the baseline and six-month Lp(a) values between the STEMI and NSTEMI groups and between the group which received evolocumab and the group that did not. Conclusion: This study demonstrated that Lp(a) levels in individuals with acute MI are significantly higher six months after the initial event. Therefore, a single measurement of Lp(a) in the peri-infarction setting is not sufficient to predict the Lp(a)-associated CAD risk in the post-infarction period. Registration: Evolocumab in Acute Coronary Syndrome Trial [EVACS I] NCT03515304, Evolocumab in Patients with Acute Myocardial Infarction [EVACS II], NCT04082442.

The role of proprotein convertase subtillisin/kexin type 9 in placental salvage and lipid metabolism in women with preeclampsia.

INTRODUCTION: Preeclampsia is associated with decreased maternal low-density lipoprotein cholesterol (LDL-c), which is essential for fetal growth. The underlying mechanisms for decreased LDL-c in preeclampsia remain unknown. Proprotein convertase subtillisin/kexin type 9 (PCSK9) regulates serum LDL-c via LDL receptor (LDL-R) degradation. We describe the possible role of PCSK9 in lipid metabolism in all compartments of the parturient (maternal blood, placental tissue, and fetal blood) in pregnancies with and without preeclampsia. METHODS: This is an observational study examining PCSK9 levels in maternal sera, umbilical cord blood, and PCSK9 protein content in placental tissue in three different locations (maternal placental interface, fetal placental interface, and umbilical cord) in women with and without preeclampsia at >23 weeks gestation. RESULTS: 68 parturients with preeclampsia and 55 without preeclampsia were enrolled. Maternal serum LDL-c (116.6 ± 48.9 mg/dL vs 146.1 ± 47.1 mg/dL, p = 0.0045) and PCSK9 (83 [61.8127.6] ng/mL vs 105.3 [83.5142.9] ng/mL, p = 0.011) were also reduced in the preeclamptics versus controls. There were no differences in PCSK9 protein content between preeclamptics and controls at comparative placental interfaces. However, PCSK9 protein content increased between the preeclampsia maternal placental interface (1.87 ± 0.62) and the preeclampsia umbilical cord (2.67 ± 1.08, p = 0.0243). DISCUSSION: PCSK9 levels are lower in maternal sera in preeclampsia when compared to controls. Placental PCSK9 protein content in preeclampsia increases from the maternal interface to the umbilical cord; however, this is not seen in controls. This suggests a potential compensatory mechanism for PCSK9 which allows for higher circulating fetal LDL-c levels in preeclampsia.

Effect of Sex on Coronary Endothelial Dysfunction in People Living With HIV.

Background Impaired coronary endothelial function (CEF) predicts cardiovascular events and occurs in people living with HIV (PLWH). Women compared with men living with HIV have worse cardiovascular outcomes, but prior CEF studies included few women. The authors aimed to compare CEF in women with HIV versus without HIV, investigate sex differences in CEF and PCSK9 (proprotein convertase subtilisin/kexin type 9) (a proinflammatory biomarker), and evaluate whether increased serum levels of PCSK9 are associated with CEF in PLWH. Methods and Results Magnetic resonance imaging was performed to measure CEF (as percent change in coronary cross-sectional area and coronary blood flow during isometric handgrip exercise, an endothelial-dependent stressor) and serum PCSK9 levels were measured in 106 PLWH and 76 people without HIV. CEF was significantly reduced in women with versus without HIV (cross-sectional area change -0.5%±9.7 versus 9.5%±3.2, respectively). After adjustment for age, body mass index, and menopausal status, women with HIV still had reduced CEF (percentage of cross-sectional area: ß -8.3 [-13 to -3.6], P=0.001) compared with women without HIV. PCSK9 was elevated in women living with HIV versus without (306 ng/mL [200-412 ng/mL] versus 180 ng/mL [154-223 ng/mL], P<0.001), and no sex differences in either CEF or PCSK9 were detected in PLWH. Elevated PCSK9 was associated with impaired CEF in PLWH; however, no significant sex differences in the association were detected. Conclusions Among PLWH, coronary endothelial dysfunction is present in women and comparable to men. PCSK9 is higher in women with versus without HIV and a significant inverse relationship between PCSK9 and CEF was shown. Future studies should determine whether PLWH would benefit from interventions to improve endothelial function.

Plasma Proprotein Convertase Subtilisin/kexin Type 9 (PCSK9) in the Acute Respiratory Distress Syndrome.

Background: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a serine protease that is a mediator of the immune response to sepsis. PCSK9 is also highly expressed in pneumocytes and pulmonary endothelial cells. We hypothesized that serum PCSK9 levels would be associated with death and ICU outcomes in patients with ARDS. Methods: Using data and plasma samples from the NIH BioLINCC data repository, we assembled a cohort of 1,577 patients with the acute respiratory distress syndrome (ARDS) enrolled in two previously completed clinical trials, EDEN and SAILS. We measured PCSK9 levels in plasma within 24 h of intubation using commercially available ELISA kits (R&D Systems). We assessed the association of PCSK9 with mortality using Cox proportional hazard models. We also assessed clinical factors associated with PCSK9 level and the association of PCSK9 with the number of days free of mechanical ventilation and days free of ICU care. Results: In 1,577 ARDS patients, median age was 53 years (IQR 42-65 years) and median APACHE III score 91 (72-111) connoting moderate critical illness. PCSK9 levels were 339.3 ng/mL (IQR 248.0-481.0). In multivariable models, race, cause of ARDS, body mass index, pre-existing liver disease, body temperature, sodium, white blood cell count and platelet count were associated with PCSK9 level. Presence of sepsis, use of vasopressors and ventilator parameters were not associated with PCSK9 level. PCSK9 levels were not associated with in-hospital mortality (HR per IQR 0.96, 95% CI 0.84-1.08, P = 0.47). Higher PCSK9 levels were associated with fewer ICU and ventilator free days. Conclusions: Plasma PCSK9 is not associated with mortality in ARDS, however higher PCSK9 levels are associated with secondary outcomes of fewer ICU free and ventilator free days. Clinical factors associated with PCSK9 in ARDS are largely unmodifiable. Further research to define the mechanism of this association is warranted.

Markers of endothelial cell activation are associated with the severity of pulmonary disease in COVID-19.

Severe coronavirus disease-19 (COVID-19) is characterized by vascular inflammation and thrombosis. We and others have proposed that the inflammatory response to coronavirus infection activates endothelial cells, leading to endothelial release of pro-thrombotic proteins. These mediators can trigger obstruction of the pulmonary microvasculature, leading to worsening oxygenation, acute respiratory distress syndrome, and death. In the current study, we tested the hypothesis that higher levels of biomarkers released from endothelial cells are associated with worse oxygenation in patients with COVID-19. We studied 83 participants aged 18-84 years with COVID-19 admitted to a single center. The severity of pulmonary disease was classified by oxygen requirement, including no oxygen requirement, low-flow oxygen, high-flow nasal cannula oxygen, mechanical ventilation, and death. We measured plasma levels of two proteins released by activated endothelial cells, von Willebrand Factor (VWF) antigen and soluble P-Selectin (sP-Sel), and a biomarker of systemic thrombosis, D-dimer. Additionally, we explored the association of endothelial biomarker levels with the levels of pro-inflammatory cytokine and chemokines, and vascular inflammation biomarkers. We found that levels of VWF, sP-sel, and D-dimer were increased in individuals with more severe COVID-19 pulmonary disease. Biomarkers of endothelial cell activation were also correlated with proinflammatory cytokines and chemokines. Taken together, our data demonstrate increased levels of VWF and sP-selectin are linked to the severity of lung disease in COVID-19 and correlated with biomarkers of inflammation and vascular inflammation. Our data support the concept that COVID-19 is a vascular disease which involves endothelial injury in the context of an inflammatory state.

The Trajectory of Lipoprotein(a) During the Peri- and Early Postinfarction Period and the Impact of Proprotein Convertase Subtilisin/Kexin Type 9 Inhibition.

Lipoprotein(a), or Lp(a), levels and the effect of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition on Lp(a) during the peri-infarction and early postinfarction period are not well characterized. This study aimed to describe the trajectory of Lp(a), as well as the effect of PCSK9 inhibition on that trajectory during the peri-infarction and early postinfarction period. Lp(a) levels were obtained within 24 hours of hospital admission as well as within 24 hours of hospital discharge and at 30 days from 74 participants who presented with a NSTEMI (troponin I >5 ng/ml) or with a STEMI and were enrolled in 2 randomized, double-blind trials of evolocumab and placebo (Evolocumab in Acute Coronary Syndrome [EVACS I]; ClinicalTrials.gov, NCT03515304 and Evolocumab in Patients With STEMI [EVACS II]; ClinicalTrials.gov Identifier: NCT04082442). There was a significant increase from the pretreatment level in the placebo-treated patients, from 64 (41,187) nmol/L to 80 (47, 172) nmol/L at hospital discharge and to 82 (37, 265) at 30 days. This was primarily driven by the results from participants with high Lp(a) at hospital admission (>75 nmol/L) in whom the median increase was 28% as compared with a 10% increase in those with pretreatment Lp(a) of <75 nmol/L. In contrast, there was no significant change from the pretreatment level in the evolocumab-treated patients regardless of pretreatment Lp(a) levels. In conclusion, Lp(a) rises during the peri-infarction and early postinfarction period in patients with acute myocardial infarction. The increase was prevented by a single dose of subcutaneous evolocumab given within 24 hours of hospital admission.

Coronary heart disease risk: Low-density lipoprotein and beyond.

Coronary heart disease (CHD) is the leading cause of morbidity and mortality world-wide and has been characterized as a chronic immunoinflammatory, fibroproliferative disease fueled by lipids. Great advances have been made in elucidating the complex mechanistic interactions among risk factors associated with CHD, yielding abundant success towards preventive measures and the development of pharmaceuticals to prevent and treat CHD via attenuation of lipoprotein-mediated risk. However, significant residual risk remains. Several potentially modifiable CHD risk factors ostensibly contributing to this residual risk have since come to the fore, including systemic inflammation, diabetes mellitus, high-density lipoprotein, plasma triglycerides (TG) and remnant lipoproteins (RLP), lipoprotein(a) (Lp[a]), and vascular endothelial dysfunction (ED). Herein, we summarize the body of evidence implicating each of these risk factors in residual CHD risk.

Effect of Crizanlizumab, a P-Selectin Inhibitor, in COVID-19: A Placebo-Controlled, Randomized Trial.

COVID-19 is characterized by vascular inflammation and thrombosis, including elevations in P-selectin, a mediator of inflammation released by endothelial cells. We tested the effect of P-selectin inhibition on biomarkers of thrombosis and inflammation in patients with COVID-19. Hospitalized patients with moderate COVID-19 were randomly assigned to receive either placebo or crizanlizumab, a P-selectin inhibitor, in a double-blind fashion. Crizanlizumab reduced P-selectin levels by 89%. Crizanlizumab increased D-dimer levels by 77% and decreased prothrombin fragment. There were no significant differences between crizanlizumab and placebo for clinical endpoints. Crizanlizumab was well tolerated. Crizanlizumab may induce thrombolysis in the setting of COVID-19. (Crizanlizumab for Treating COVID-19 Vasculopathy [CRITICAL]; NCT04435184).

Comparison of Ticagrelor Versus Clopidogrel on Cerebrovascular Microembolic Events and Platelet Inhibition during Transcatheter Aortic Valve Implantation.

The impact of the antiplatelet regimen and the extent of associated platelet inhibition on cerebrovascular microembolic events during transcatheter aortic valve implantation (TAVI) are unknown. Our aim was to evaluate the effects of ticagrelor versus clopidogrel and of platelet inhibition on the number of cerebrovascular microembolic events in patients undergoing TAVI. Patients scheduled for TAVI were randomized previous to the procedure to either aspirin and ticagrelor or to aspirin and clopidogrel. Platelet inhibition was expressed in P2Y12 reaction units (PRU) and percentage of inhibition. High intensity transient signals (HITS) were assessed with transcranial Doppler (TCD). Safety outcomes were recorded according to the VARC-2 definitions. Among 90 patients randomized, 6 had an inadequate TCD signal. The total number of procedural HITS was lower in the ticagrelor group (416.5 [324.8, 484.2]) (42 patients) than in the clopidogrel group (723.5 [471.5, 875.0]) (42 patients), p <0.001. After adjusting for the duration of the procedure, diabetes, extra-cardiac arteriopathy, BMI, hypertension, aortic valve calcium content, procedural ACT, and pre-implantation balloon valvuloplasty, patients on ticagrelor had on average 256.8 (95% CI: [-335.7, -176.5]) fewer total procedural HITS than patients on clopidogrel. Platelet inhibition was greater with ticagrelor 26 [10, 74.5] PRU than with clopidogrel 207.5 (120 to 236.2) PRU, p <0.001, and correlated significantly with procedural HITS (r = 0.5, p <0.05). In conclusion, ticagrelor resulted in fewer procedural HITS, compared with clopidogrel, in patients undergoing TAVI, while achieving greater platelet inhibition.