Differences in Whole Blood Platelet Aggregation at Baseline and in Response to Aspirin and Aspirin Plus Clopidogrel in Patients With Versus Without Chronic Kidney Disease

Review on Kidney-Liver Crosstalk: Pathophysiology of Their Disorders

Kidney-liver crosstalk plays a crucial role in normal and certain pathological conditions. In pathologic states, both renal-induced liver damage and liver-induced kidney diseases may happen through these kidney-liver interactions. This bidirectional crosstalk takes place through the systemic conditions that mutually influence both the liver and kidneys. Ischemia and reperfusion, cytokine release and pro-inflammatory signaling pathways, metabolic acidosis, oxidative stress, and altered enzyme activity and metabolic pathways establish the base of this interaction between the kidneys and liver. In these concomitant kidney-liver diseases, the survival rates strongly correlate with early intervention and treatment of organ dysfunction. Proper care of a nephrologist and hepatologist and the identification of pathological conditions using biomarkers at early stages are necessary to prevent the complications induced by this complex and potentially vicious cycle. Therefore, understanding the characteristics of this crosstalk is essential for better management. In this review, we discussed the available literature concerning the detrimental effects of kidney failure on liver functions and liver-induced kidney diseases.

Updates on New Therapies for Patients with CKD

Individuals diagnosed with chronic kidney disease (CKD) continue to increase globally. This group of patients experience a disproportionately higher risk of cardiovascular (CV) events compared to the general population. Despite multiple guidelines-based medical management, patients with CKD continue to experience residual cardiorenal risk. Several potential mechanisms explain this excessive CV risk observed in individuals with CKD. Several new drugs have become available that could potentially transform CKD care, given their efficacy in this patient population. Nevertheless, use of these drugs presents certain benefits and challenges that are often underrecognized by prescribing these drugs. In this review, we aim to provide a brief discussion about CKD pathophysiology, limiting our discussion to recent published studies. We also explore benefits and limitations of newer drugs, including angiotensin receptor/neprilysin inhibitors (ARNI), sodium glucose transporter 2 inhibitors (SGLT2i), glucagon-like peptides-1 (GLP-1) agonists and finerenone in patients with CKD. Despite several articles covering this topic, our review provides an algorithm where subgroups of patients with CKD might benefit the most from such drugs based on the selection criteria of the landmark trials. Patients with CKD who have nephrotic range proteinuria beyond 5000 mg/g, or those with poorly controlled blood pressure (systolic ≥160 mm Hg or diastolic ≥100 mm Hg) remain understudied.

Antiplatelet Therapy in End-stage Renal Disease Patients on Maintenance Dialysis: a State-of-the-art Review

Patients with end-stage renal disease (ESRD) on maintenance dialysis have an increased risk of ischaemic events, such as recurrent myocardial infarction (MI) and stroke. Potent antiplatelet therapy may help mitigate this risk. Nonetheless, ERSD patients are also at increased risk of bleeding due to their complex vascular milieu, which limits the routine use of potent P2Y12 inhibitors. Moreover, these patients are often underrepresented or excluded from major clinical trials leaving a significant gap in existing knowledge. Understanding the mechanisms of this paradox may serve as a benchmark for the development of ESRD trials. The present review aims to provide an overview of the pathophysiological nature of increased bleeding and ischaemic risks in ERSD patients as well as summarize available evidence of antiplatelet use and propose new concepts to guide physicians in selecting appropriate drug regimes for this high-risk cohort.

Baseline P2Y12 reactivity, kidney function, and CYP2C19 genotype determine clopidogrel responsiveness in acute stroke

Clopidogrel is the most-widely used platelet P2Y12-inhibitor for secondary-prevention of ischemic stroke. Platelet P2Y12 reactivity before and after inhibitors can be measured with blood sampling by commercialized system. We aimed to evaluate (1) whether high-on-clopidogrel platelet P2Y12 reactivity (HCPR) is associated with short-term vascular events and (2) the predictors of HCPR in acute stroke. The inclusion criterion was patients with acute stroke who received clopidogrel within 12-48 h after the onset. Platelet reactivity was assayed at baseline and after clopidogrel treatment using the VerifyNow system. The primary endpoint was recurrent ischemic events within 21 days after stroke. Among 190 patients, 32(16.9%) had recurrent ischemic stroke. Multivariate analyses showed that HCPR was significantly associated with the short-term events with an odds-ratio of 2.5 (95% CI 1.1-5.7, p = 0.027). Patients with HCPR had significantly higher frequencies of high baseline platelet P2Y12 reactivity, impaired kidney function, and carrying one or two CYP2C19 loss-of-function alleles. A poor clopidogrel response score combining these factors was developed. Ten percent of patients with score 0, 20.3% of those with score 1, 38.3% of those with score 2, and 66.7% of those with score 3 had HCPR (χ²-test, p < 0.001). Multivariate analyses showed that, compared with the score-0 group, the score-2 and -3 groups had higher risks of HCPR with hazard-ratios of 5.4 (95% CI 1.5-20.3, p = 0.012) and 17.4 (95% CI 3.4-88.9, p = 0.001) for developing recurrent ischemic strokes. The study emphasized the role of HCPR in ischemic stroke. We also developed an HCPR risk score, which could be used in clinical practice or trials, potentially with more precision, to weigh the clinical benefit of a tailored antiplatelet-strategy for patients with stroke.

Ticagrelor inhibits platelet aggregation and reduces inflammatory burden more than clopidogrel in patients with stages 4 or 5 chronic kidney disease

BACKGROUND

No study has compared pharmacologic properties of ticagrelor and clopidogrel in non-dialysis patients with stage 4-5 chronic kidney disease (CKD).

METHODS

We conducted a double-blind RCT to compare effects of ticagrelor and clopidogrel in 48 CKD, with the primary outcome of ADP-induced platelet aggregation (WBPA) after 2 weeks of DAPT. In a parallel arm, we compared effects of 2 weeks of ticagrelor plus aspirin on mean changes in WBPA and markers of thromboinflammation among non-CKD controls (n = 26) with that of CKD in the ticagrelor-arm.

RESULTS

Average age of CKD was 53.7 years, with 62% women, 54% African American, and 42% with stage 5 CKD. Ticagrelor generated statistically lower WBPA values post treatment [median 0 Ω (IQR 0, 2)] vs. clopidogrel [median 0 Ω (IQR 0, 5)] (P = 0.002); percent inhibition of WBPA was greater (87 ± 22% vs. 63 ± 50%; P = 0.04; and plasma IL-6 levels were much lower (8.42 ± 1.73 pg/ml vs. 18.48 ± 26.56 pg/ml; P = 0.04). No differences in mean changes in WBPA between CKD-ticagrelor and control groups were observed. Ticagrelor- DAPT reduced levels of IL-1α and IL-1β in CKD-ticagrelor and control groups, attenuated lowering of TNFα and TRAIL levels in CKD-ticagrelor (vs controls), and had global changes in correlation between various cytokines in a subgroup of CKD-ticagrelor subjects not on statins (n = 10). Peak/trough levels of ticagrelor/metabolite were not different between CKD-ticagrelor and control groups.

CONCLUSIONS

We report significant differences in platelet aggregation and anti-inflammatory properties between ticagrelor- and clopidogrel-based DAPT in non-dialysis people with stage 4-5 CKD. These notable inflammatory responses suggest ticagrelor-based DAPT might lower inflammatory burden of asymptomatic patients with stage 4 or 5 CKD. (clinicaltrials.gov # NCT03649711).

Platelet-Dependent Inflammatory Dysregulation in Patients with Stages 4 or 5 Chronic Kidney Disease: A Mechanistic Clinical Study

Background

Chronic kidney disease (CKD) is characterized by dysregulated inflammation that worsens with CKD severity. The role of platelets in modulating inflammation in stage 4 or 5 CKD remains unexplored. We investigated whether there are changes in platelet-derived thromboinflammatory markers in CKD with dual antiplatelet therapy (DAPT; aspirin 81 mg/d plus P2Y12 inhibitor).

Methods

In a mechanistic clinical trial, we compared platelet activation markers (aggregation and surface receptor expression), circulating platelet-leukocyte aggregates, leukocyte composition (monocyte subtypes and CD11b surface expression), and plasma cytokine profile (45 analytes) of non-CKD controls (n=26) and CKD outpatients (n=48) with a glomerular filtration rate (GFR) <30 ml/min per 1.73 m² on 2 weeks of DAPT.

Results

Patients with CKD demonstrated a reduced mean platelet count, elevated mean platelet volume, reduced platelet-leukocyte aggregates, reduced platelet-bound monocytes, higher total non-classic monocytes in the circulation, and higher levels of IL-1RA, VEGF, and fractalkine (all P<0.05). There were no differences in platelet activation markers between CKD and controls. Although DAPT reduced platelet aggregation in both groups, it had multifaceted effects on thromboinflammatory markers in CKD, including a reduction in PDGF levels in all CKD individuals, reductions in IL-1β and TNF-α levels in select CKD individuals, and no change in a number of other cytokines. Significant positive correlations existed for baseline IL-1β, PDGF, and TNF-α levels with older age, and for baseline TNF-α levels with presence of diabetes mellitus and worse albuminuria. Mean change in IL-1β and PDGF levels on DAPT positively correlated with younger age, mean change in TNF-α levels with higher GFR, and mean changes in PDGF, and TRAIL levels correlated with worse albuminuria. Minimum spanning trees plot of cytokines showed platelet-derived CD40L had a large reduction in weight factor after DAPT in CKD. Additionally, platelet-derived IL-1β and PDGF were tightly correlated with other cytokines, with IL-1β as the hub cytokine.

Conclusions

Attenuated interactions between platelets and leukocytes in the CKD state coincided with no change in platelet activation status, an altered differentiation state of monocytes, and heightened inflammatory markers. Platelet-derived cytokines were one of the central cytokines in patients with CKD that were tightly correlated with others. DAPT had multifaceted effects on thromboinflammation, suggesting that there is platelet-dependent and -independent inflammation in stage 4 or 5 CKD.

Platelet Activity and Cardiovascular Risk in CKD and Peripheral Artery Disease

Introduction

Platelet dysfunction and cardiovascular risk are well-recognized features of chronic kidney disease (CKD). Platelets drive the development and progression of cardiovascular disease (CVD). The relationships between kidney function, platelet activity, and cardiovascular risk are poorly defined.

Methods

We compared platelet activity and incident cardiovascular events by CKD status (estimated glomerular filtration rate [eGFR] < 60 ml/min per 1.73 m²) using data from the Platelet Activity and Cardiovascular Events study, a prospective cohort study that enrolled adults with peripheral artery disease (PAD) undergoing lower extremity revascularization. Platelet activity was measured using light transmission aggregometry (LTA) in response to submaximal dose agonist stimulation, and the subjects were followed for incident adverse cardiovascular events for a median of 18 months.

Results

Overall, 113 of 285 (40%) subjects had CKD. Subjects with, versus without, CKD had higher platelet aggregation in response to stimulation with adenosine diphosphate (ADP), serotonin, epinephrine, and arachidonic acid (AA) + ex vivo aspirin (P < 0.05 for each). Following multivariable adjustment, subjects with CKD had elevated risk for myocardial infarction (MI) (adjusted hazard ratio 2.2, 95% confidence interval [1.02–4.9]) and major adverse cardiovascular events (MACE) (1.9 [1.2–3.3]) compared to those without CKD. Platelet aggregation in response to submaximal dose agonist stimulation mediated 7% to 26% of the excess risk for cardiovascular events associated with CKD.

Conclusion

Among subjects with PAD undergoing lower extremity revascularization, CKD is associated with increased platelet activity that mediates, in part, elevated cardiovascular risk.

Platelet Abnormalities in CKD and Their Implications for Antiplatelet Therapy

Patients with CKD display a significantly higher risk of cardiovascular and thromboembolic complications, with around half of patients with advanced CKD ultimately dying of cardiovascular disease. Paradoxically, these patients also have a higher risk of hemorrhages, greatly complicating patient therapy. Platelets are central to hemostasis, and altered platelet function resulting in either platelet hyper- or hyporeactivity may contribute to thrombotic or hemorrhagic complications. Different molecular changes have been identified that may underlie altered platelet activity and hemostasis in CKD. In this study, we summarize the knowledge on CKD-induced aberrations in hemostasis, with a special focus on platelet abnormalities. We also discuss how prominent alterations in vascular integrity, coagulation, and red blood cell count in CKD may contribute to altered hemostasis in these patients who are high risk. Furthermore, with patients with CKD commonly receiving antiplatelet therapy to prevent secondary atherothrombotic complications, we discuss antiplatelet treatment strategies and their risk versus benefit in terms of thrombosis prevention, bleeding, and clinical outcome depending on CKD stage. This reveals a careful consideration of benefits versus risks of antiplatelet therapy in patients with CKD, balancing thrombotic versus bleeding risk. Nonetheless, despite antiplatelet therapy, patients with CKD remain at high cardiovascular risk. Thus, deep insights into altered platelet activity in CKD and underlying mechanisms are important for the optimization and development of current and novel antiplatelet treatment strategies, specifically tailored to these patients who are high risk. Ultimately, this review underlines the importance of a closer investigation of altered platelet function, hemostasis, and antiplatelet therapy in patients with CKD.

Comparative Effectiveness and Safety of Oral P2Y12 Inhibitors in Patients on Chronic Dialysis

Introduction

Although oral P2Y₁₂ inhibitors (P2Y12-Is) are one of the most commonly prescribed medication classes in patients with end stage kidney disease on dialysis (ESKD), scarce data exist regarding their benefits and risks.

Methods

We compared effectiveness and safety of clopidogrel, prasugrel, and ticagrelor in a longitudinal study using the United States Renal Data System registry of Medicare beneficiaries with ESKD. Individuals who filled new P2Y12-I prescriptions between 2011 and 2015 were included and followed until death or censoring. The primary exposure variable was P2Y12-I assignment. The primary outcome variable was death. Secondary outcomes included cardiovascular (CV) death, coronary revascularization, and gastrointestinal (GI) hemorrhage. Survival analyses were performed after propensity matching.

Results

Of 44,619 patients with ESKD who received P2Y12-Is, 95% received clopidogrel (n = 42,523), 3% prasugrel (n = 1205), and 2% ticagrelor (n = 891). To balance baseline differences, propensity-matching was performed: 1:6 for prasugrel (n = 1189) versus clopidogrel (n = 7134); 1:4 for ticagrelor (n = 880) versus clopidogrel (n = 3520); and 1:1 for ticagrelor versus prasugrel (n = 880). Prasugrel was associated with a reduced risk for death versus clopidogrel and ticagrelor (adjusted hazard ratio [HR] = 0.82; 95% CI: 0.73–0.93 and 0.78; 95% CI: 0.64–0.95). Compared with clopidogrel, prasugrel reduced risk for coronary revascularization (HR = 0.91; 95% CI: 0.86–0.96). There were no differences in GI hemorrhage between P2Y12-Is.

Conclusion

In patients with ESKD, prasugrel compared with others reduced risk of death possibly by reducing risk for coronary revascularizations and without worsening gastrointestinal hemorrhage. Future trials are imperative to compare efficacy and safety of P2Y12-Is in patients with ESKD.

Use of Sertraline in Hemodialysis Patients

Depression and anxiety are the most common psychiatric disorders in end-stage renal disease (ESRD) patients treated with hemodialysis (HD) and may correlate with lower quality of life and increased mortality. Depression treatment in HD patients is still a challenge both for nephrologists and psychiatrists. The possible treatment of depressive disorders can be pharmacological and non-pharmacological. In our article, we focus on the use of sertraline, the medication which seems to be relatively safe and efficient in the abovementioned population, taking under consideration several limitations regarding the use of other selective serotonin reuptake inhibitors (SSRIs). In our paper, we discuss different aspects of sertraline use, taking into consideration possible benefits and side effects of drug administration like impact on QTc (corrected QT interval) prolongation, intradialytic hypotension (IDH), chronic kidney disease-associated pruritus (CKD-aP), bleeding, sexual functions, inflammation, or fracture risk. Before administering the medication, one should consider benefits and possible side effects, which are particularly significant in the treatment of ESRD patients; this could help to optimize clinical outcomes. Sertraline seems to be safe in the HD population when provided in proper doses. However, we still need more studies in this field since the ones performed so far were usually based on small samples and lacked placebo control.

Platelet Function in CKD: A Systematic Review and Meta-Analysis

BACKGROUND

Patients with CKD are at high risk for thrombotic and hemorrhagic complications. Abnormalities in platelet function are central to these complications, but reports on platelet function in relation to CKD are conflicting, and vary from decreased platelet reactivity to normal or increased platelet responsiveness. The direct effects of uremic toxins on platelet function have been described, with variable findings.

METHODS

To help clarify how CKD affects platelet function, we conducted a systematic review and meta-analysis of platelet activity in CKD, with a focus on nondialysis-induced effects. We also performed an extensive literature search for the effects of individual uremic toxins on platelet function.

RESULTS

We included 73 studies in the systematic review to assess CKD's overall effect on platelet function in patients; 11 of them described CKD's effect on ex vivo platelet aggregation and were included in the meta-analysis. Although findings on platelet abnormalities in CKD are inconsistent, bleeding time was mostly prolonged and platelet adhesion mainly reduced. Also, the meta-analysis revealed maximal platelet aggregation was significantly reduced in patients with CKD upon collagen stimulation. We also found that relatively few uremic toxins have been examined for direct effects on platelets ex vivo; ex vivo analyses had varying methods and results, revealing both platelet-stimulatory and inhibitory effects. However, eight of the 12 uremic toxins tested in animal models mostly induced prothrombotic effects.

CONCLUSIONS

Overall, most studies report impaired function of platelets from patients with CKD. Still, a substantial number of studies find platelet function to be unchanged or even enhanced. Further investigation of platelet reactivity in CKD, especially during different CKD stages, is warranted.

Role of Platelets in Chronic Kidney Disease

Platelet-dependent mechanisms for excessive clotting and bleeding in CKD remain undefined. Moreover, platelets' contribution to inflammation, and specifically to CKD, are equally elusive. To date, descriptions of changes in the functional properties of circulating platelets during CKD have provided confusing interpretations. Experimental approaches that can advance our understanding of platelet dysfunction in CKD are needed, and studies that provide mechanistic insights into the dynamic relationships between thrombosis, bleeding, and inflammation associated with CKD will be essential to improve clinical management and outcomes for this vulnerable population. This article summarizes existing literature characterizing platelets in CKD and identifies areas that need further investigation.

Renohepatic crosstalk: a review of the effects of acute kidney injury on the liver

Several theories regarding acute kidney injury (AKI)-related mortality have been entertained, although mounting evidence supports the paradigm that impaired kidney function directly and adversely affects the function of several remote organs. The kidneys and liver are fundamental to human metabolism and detoxification, and it is therefore hardly surprising that critical illness complicated by hepatorenal dysfunction portends a poor prognosis. Several diseases can simultaneously impact the proper functioning of the liver and kidneys, although this review will address the impact of AKI on liver function. While evidence for this relationship in humans remains sparse, we present supportive studies and then discuss the most likely mechanisms by which AKI can cause liver dysfunction. These include 'traditional' complications of AKI (uremia, volume overload and acute metabolic acidosis, among others) as well as systemic inflammation, hepatic leukocyte infiltration, cytokine-mediated liver injury and hepatic oxidative stress. We conclude by addressing the therapeutic implications of these findings to clinical medicine.

Monitoring Antiplatelet Aggregation In Vivo and In Vitro by Microtiter Plate Method

BACKGROUND

The current light transmission aggregation method is a recognized conventional method for platelet function evaluation, but it is time-consuming and poor in parallelism and cannot simultaneously monitor multiple inducers at multiple levels. The microtiter plate method has been established because of the high-throughput characteristic, but it needs more practical applications.

OBJECTIVES

To evaluate the microtiter plate method by using aspirin and clopidogrel in vivo and in vitro.

METHODS

In vitro, the platelet aggregations inhibited by aspirin (0.3, 1, 3, 10, 30, 90 μM) and clopidogrel (1, 3, 10, 30, 100, 300 μM) were evaluated with the presence of arachidonic acid (AA) and adenosine diphosphate (ADP) agonists. Using the combination index (CI), the effect of the combination of aspirin and clopidogrel on platelet aggregation was evaluated. In vivo, New Zealand rabbits (n = 18) were randomly divided into 3 groups, aspirin group (5 mg/kg, intragastrical gavage [i.g.]), clopidogrel group (14 mg/kg at the first day, followed by 4 mg/kg, i.g.), and the combination of these two drugs, administered (i.g.) continuously for 7 days. Then, the blood was collected to measure platelet aggregation.

RESULTS

Different concentrations of AA (12.5, 25, 50, 100 μM) and ADP (1.25, 2.5, 5, 10 μM) could promote platelet aggregation in concentration-dependent manner, and the most stable induction concentrations of AA and ADP were 50 and 5 μM. In vitro, with the above optimized detection system, aspirin and clopidogrel alone or in combination had concentration-dependent antiplatelet aggregation. The combination of aspirin and clopidogrel also showed synergistic inhibition effect within the concentration range studied. In vivo, aspirin and clopidogrel alone or in combination inhibited platelet aggregation induced by multiple concentrations of AA and ADP agonists, and the combined inhibition was more significant during the administration than aspirin or clopidogrel alone.

CONCLUSIONS

The improved microtiter plate method combining the use of multiple levels of multiple agonists avoids the variation of the effective inducer concentrations due to individual different response of platelets to agonists. It may be a potential approach in the detection of platelet aggregation.

Receptor for Advanced Glycation End Products is Involved in Platelet Hyperactivation and Arterial Thrombosis during Chronic Kidney Disease

BACKGROUND

 Chronic kidney disease (CKD) is associated with a high cardiovascular mortality due to increased rates of vascular lesions and thrombotic events, as well as serum accumulation of uremic toxins. A subgroup of these toxins (advanced glycation end products [AGEs] and S100 proteins) can interact with the receptor for AGEs (RAGE). In this study, we analyzed the impact of CKD on platelet function and arterial thrombosis, and the potential role of RAGE in this process.

METHODS

 Twelve weeks after induction of CKD in mice, platelet function and time to complete carotid artery occlusion were analyzed in four groups of animals (sham-operated, CKD, apolipoprotein E [Apoe]^-/-, and Apoe^-/-/Ager^-/- mice).

RESULTS

 Analysis of platelet function from whole blood and platelet-rich plasma showed hyperactivation of platelets only in CKD Apoe^-/- mice. There was no difference when experiments were done on washed platelets. However, preincubation of such platelets with AGEs or S100 proteins induced RAGE-mediated platelet hyperactivation. In vivo, CKD significantly reduced carotid occlusion times of Apoe^-/- mice (9.2 ± 1.1 vs. 11.1 ± 0.6 minutes for sham, p < 0.01). In contrast, CKD had no effect on occlusion times in Apoe^-/-/Ager^-/- mice. Moreover, carotid occlusion in Apoe^-/- CKD mice occurred significantly faster than in Apoe^-/-/Ager^-/- CKD mice (p < 0.0001).

CONCLUSION

 Our results show that CKD induces platelet hyperactivation, accelerates thrombus formation in a murine model of arterial thrombosis, and that RAGE deletion has a protective role. We propose that RAGE ligands binding to RAGE is involved in CKD-induced arterial thrombosis.

Association of platelet function with depression and its treatment with sertraline in patients with chronic kidney disease: analysis of a randomized trial

BACKGROUND

Major Depressive Disorder (MDD) can lead to adverse cardiovascular outcomes in patients with chronic kidney disease (CKD). Although one of the proposed mechanisms is heightened platelet activation, effects of MDD and its treatment with a selective serotonin reuptake inhibitor (SSRI) on platelet function in patients with CKD remain unclear.

METHODS

In a pre-specified analysis, changes from baseline to 12 weeks in whole blood platelet aggregation (WBPA) and plasma levels of E-selectin and P-selectin on treatment with sertraline vs. placebo were investigated in 175 patients with CKD (estimated glomerular filtration rate [eGFR] < 60 ml/min/1.73m2) and MDD (MDD+/CKD+) in a randomized, double-blind trial. Correlations between severity of depressive symptoms and platelet function were also analyzed. In order to investigate whether differences in platelet function were due to presence of CKD or MDD, we compared a subgroup of 49 MDD+/CKD+ patients with eGFR < 30 ml/min/1.73m2 to 43 non-depressed CKD controls (28 CKD with eGFR < 30 ml/min/1.73m2 [MDD-/CKD+] and 15 individuals with eGFR ≥90 ml/min/1.73m2 [MDD-/CKD-].

RESULTS

In MDD+/CKD+ individuals, there were no significant correlations between severity of depressive symptoms and platelet function, and no significant changes in platelet function after 12 weeks of treatment with sertraline vs. placebo. There were no significant differences in platelet function among MDD+/CKD+ patients and controls without MDD except in WBPA to 10 μM ADP (P = 0.03). WBPA to ADP was lower in the MDD-/CKD- group (8.0 Ω [5.0 Ω, 11.0 Ω]) as compared to the MDD-/CKD+ group (12.5 Ω [8.0 Ω, 14.5 Ω]), P = 0.01, and the MDD+/CKD+ group (11.0 Ω [8.0 Ω, 15.0 Ω]), P < 0.01.

CONCLUSIONS

Heightened ADP-induced platelet aggregability was observed in CKD patients compared to controls with normal kidney function, regardless of presence of comorbid MDD, and treatment with sertraline did not affect platelet function. These findings suggest that increased platelet activation may not be a major contributory underlying mechanism by which depression may lead to worse cardiovascular outcomes in patients with CKD. Future studies should include positive MDD controls without CKD to confirm our findings.

TRIAL REGISTRATION

ClinicalTrials.gov identifier numbers: CAST Study: NCT00946998 (Recruitment Status: Completed. First Posted: July 27, 2009. Results First Posted: January 30, 2018). WiCKDonASA Study: NCT01768637 (Recruitment Status: Completed. First Posted: January 15, 2013. Results First Posted: April 19, 2019).

Emerging Factors Implicated in Fibrotic Organ-Associated Thrombosis: The Case of Two Organs

Thrombosis is at the heart of cardiovascular complications observed in specific diseases. A heightened thrombosis risk above that in general population in diseases such as myelofibrosis and chronic kidney disease implicates disease-specific mediators of thrombosis. This relative lack of information regarding the mechanisms of thrombosis in specific organ pathologies hitherto has remained limited. Evolving literature implicates some soluble factors in the blood of patients with discrete disorders, inflicting fundamental changes in the components of thrombosis. In this era of precision medicine, integrating these disease-specific factors in a comprehensive thrombotic risk assessment of patients is imperative in guiding therapeutic decisions. A complex network of mechanisms regulates each organ pathology and resultant thrombotic phenotypes. This review surveys different effectors of thrombogenicity associated with two pathologically fibrotic organs used as model systems, the bone marrow and kidney, as well as focuses attention to a common inducer of fibrosis and thrombosis, lysyl oxidase.

Thieno[2,3-b]pyridine derivatives are potent anti-platelet drugs, inhibiting platelet activation, aggregation and showing synergy with aspirin

Drugs which inhibit platelet function are commonly used to prevent blood clot formation in patients with Acute Coronary Syndromes (ACS) or those at risk of stroke. The thieno[3,2-c]pyridine class of therapeutic agents, of which clopidogrel is the most commonly used, target the P2Y₁₂ receptor, and are often used in combination with acetylsalicylic acid (ASA). Six thieno[2,3-b]pyridine were assessed for in vitro anti-platelet activity; all derivatives showed effects on both platelet activation and aggregation, and showed synergy with ASA. Some compounds demonstrated greater activity when compared to clopidogrel. These compounds, therefore, represent potential novel P2Y₁₂ inhibitors for improved treatment for patients.

The incidence of slow flow after rotational atherectomy of calcified coronary arteries: A randomized study of low speed versus high speed

OBJECTIVES

The purpose of this randomized trial was to compare the incidence of slow flow between low-speed and high-speed rotational atherectomy (RA) of calcified coronary lesions.

BACKGROUND

Preclinical studies suggest that slow flow is less frequently observed with low-speed than high-speed RA because of less platelet aggregation with low-speed RA.

METHODS

This was a prospective, randomized, single center study. A total of 100 patients with calcified coronary lesions were enrolled and randomly assigned in a 1:1 ratio to low-speed (140,000 rpm) or high-speed (190,000 rpm) RA. The primary endpoint was the occurrence of slow flow following RA. Slow flow was defined as slow or absent distal runoff (Thrombolysis in Myocardial Infarction [TIMI] flow grade ≤ 2).

RESULTS

The incidence of slow flow in the low-speed group (24%) was the same as that in the high-speed group (24%) (P = 1.00; odds ratio, 1.00; 95% confidence interval, 0.40-2.50). The frequencies of TIMI 3, TIMI 2, TIMI 1, and TIMI 0 flow grades were similar between the low-speed (TIMI 3, 76%; TIMI 2, 14%; TIMI 1, 8%; TIMI 0, 2%) and high-speed (TIMI 3, 76%; TIMI 2, 14%; TIMI 1, 10%; TIMI 0, 0%) groups (P = 0.77 for trend). The incidence of periprocedural myocardial infarction was the same between the low-speed (6%) and high-speed (6%) groups (P = 1.00).

CONCLUSIONS

This randomized trial did not show a reduction in the incidence of slow flow following low-speed RA as compared with high-speed RA (UMIN ID: UMIN000015702). © 2016 Wiley Periodicals, Inc.