Impact of chronic kidney disease on platelet reactivity and outcomes of patients receiving clopidogrel and undergoing percutaneous coronary intervention

Effects of ticagrelor and prasugrel on coronary microcirculation in elective percutaneous coronary intervention

OBJECTIVE

To compare the effects of ticagrelor and prasugrel on absolute coronary blood flow (Q) and microvascular resistance (R) in patients with stable coronary artery disease (CAD) treated with elective percutaneous coronary intervention (PCI) (NCT05643586). Besides being at least as effective as prasugrel in inhibiting platelet aggregation, ticagrelor has been shown to have additional properties potentially affecting coronary microcirculation.

METHODS

We randomly assigned 50 patients to ticagrelor (180 mg) or prasugrel (60 mg) at least 12 hours before intervention. Continuous thermodilution was used to measure Q and R before and after PCI. Platelet reactivity was measured before PCI. Troponin I was measured before, 8 and 24 hours after PCI.

RESULTS

At baseline, fractional flow reserve, Q and R were similar in two study groups. Patients in the ticagrelor group showed higher post-PCI Q (242±49 vs 205±53 mL/min, p=0.015) and lower R values (311 (263, 366) vs 362 (319, 382) mm Hg/L/min, p=0.032). Platelet reactivity showed a negative correlation with periprocedural variation of Q values (r=-0.582, p<0.001) and a positive correlation with periprocedural variation of R values (r=0.645, p<0.001). The periprocedural increase in high-sensitivity troponin I was significantly lower in the ticagrelor compared with the prasugrel group (5 (4, 9) ng/mL vs 14 (10, 24) ng/mL, p<0.001).

CONCLUSIONS

In patients with stable CAD undergoing PCI, pretreatment with a loading dose of ticagrelor compared with prasugrel improves post-procedural coronary flow and microvascular function and seems to reduce the related myocardial injury.

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.

P2y12 inhibitor monotherapy after 1-3 months dual antiplatelet therapy in patients with coronary artery disease and chronic kidney disease undergoing percutaneous coronary intervention: a meta-analysis of randomized controlled trials

Introduction

In patients with coronary artery disease (CAD) and chronic kidney disease (CKD) undergoing percutaneous coronary intervention (PCI), whether short-term dual antiplatelet therapy (DAPT) followed by P2Y₁₂ inhibitors confers benefits compared with standard DAPT remains unclear. This study aimed to assess the efficacy and safety of 1-3 months of DAPT followed by P2Y₁₂ monotherapy in patients with CAD and CKD undergoing PCI.

Methods

PubMed, Embase, and the Cochrane Library were searched to identify randomized controlled trials (RCTs) comparing the P2Y₁₂ inhibitor monotherapy after a 1-3 months DAPT vs. DAPT in patients with CAD and CKD after PCI. The primary outcome was the incidence of major adverse cardiovascular events (MACEs), defined as a composite of all-cause mortality, myocardial infarction, stent thrombosis, target-vessel revascularization, and stroke. The safety outcome was the major bleeding events, defined as a composite of TIMI major bleeding or Bleeding Academic Research and Consortium (BARC) type 2, 3, or 5 bleeding. The pooled risk ratios (RRs) with 95% confidence intervals (CIs) were calculated with a fixed- or random-effects model depending on the heterogeneity among studies.

Results

Four RCTs including 20,468 patients (2,833 patients with CKD and 17,635 without CKD) comparing P2Y₁₂ inhibitor monotherapy with DAPT were included in our meta-analysis. Patients with CAD and CKD had higher risk of ischemic and bleeding events. P2Y₁₂ inhibitor monotherapy after 1-3 months of DAPT significantly reduced the risk of major bleeding compared to DAPT in CKD patients (RR: 0.69, 95% CI: 0.51-0.95, P = 0.02) and non-CKD patients (RR: 0.66, 95% CI: 0.49-0.89, P = 0.01). No significant difference regarding MACEs between P2Y₁₂ inhibitor monotherapy and DAPT was found in CKD patients (RR: 0.88, 95% CI: 0.59-1.31, P = 0.53) and non-CKD (RR: 0.91, 95% CI: 0.79-1.04, P = 0.17).

Conclusion

P2Y₁₂ inhibitor monotherapy after 1-3 months of DAPT was an effective strategy for lowering major bleeding complications without increasing the risk of cardiovascular events in patients with CAD and CKD undergoing PCI as compared with DAPT.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, CRD42022355228.

[Heart and diabetes : Platelet function and antiplatelet therapy in chronic kidney disease]

Patients with chronic kidney disease (CKD) have an increased risk of thrombosis and approximately 50% of patients with advanced CKD die because of a cardiovascular disease. In addition to an increased risk of thrombosis, patients with CKD and particularly with advanced CKD, have an increased risk of hemorrhage, which increases parallel to the decline of kidney function. Due to this parallel existence of the prohemorrhagic and prothrombotic phenotype, antiplatelet treatment is difficult in the daily routine and data show that CKD patients with acute coronary syndrome (ACS) are less likely to receive guideline-conform treatment. The underlying mechanisms are currently insufficiently understood and both platelet-dependent mechanisms and also platelet-independent mechanisms are under discussion. Accordingly, there is currently no specific treatment or treatment strategy for patients with CKD. In addition, CKD patients are underrepresented in registration studies on antiplatelet treatment and there are no data from randomized trials for patients with advanced CKD (CKD ≥ 4). Current guideline recommendations are therefore based on subgroup analyses and observational studies. In addition, questions on the duration of treatment, on risk scores for estimation of the risk of hemorrhage and on potential benefits of escalation and de-escalation strategies remain largely unanswered and should therefore be the focus of future studies.

Impact Of Chronic Kidney Disease On The Pharmacodynamic And Pharmacokinetic Effects Of Ticagrelor In Patients With Diabetes Mellitus And Coronary Artery Disease

AIMS

Patients with diabetes mellitus (DM) and chronic kidney disease (CKD) are at increased risk of atherothrombotic events. Ticagrelor reduces ischaemic events compared to clopidogrel, with the greatest risk reduction in patients with both DM and CKD. How CKD status affects the pharmacodynamic (PD) and pharmacokinetic (PK) profiles of different ticagrelor maintenance dose regimens in patients with DM is unknown.

METHODS AND RESULTS

In this randomized, cross-over study, patients with DM on treatment with dual antiplatelet therapy (aspirin and clopidogrel) were stratified according to CKD status and randomized to ticagrelor 90 mg bid or 60 mg bid. PK/PD assessments were performed at baseline, after 7-10 days of ticagrelor (peak and trough), and after 7-10 days of alternative ticagrelor regimen (peak and trough). PK assessments included plasma concentrations of ticagrelor and its major metabolite. PD assessments included VASP-PRI, VerifyNow P2Y12, and LTA.A total of 92 patients with DM (CKD, n = 44; non-CKD, n = 48) were randomized. Levels of platelet reactivity were lower with the 90 mg compared with the 60 mg ticagrelor dose, which was statistically significant in non-CKD but not in CKD patients for most PD measures. There were no significant differences in the primary endpoint (trough levels of VASP-PRI following ticagrelor 90 mg dosing) between cohorts (31 ± 20 vs 25 ± 14; p = 0.105). VerifyNow and LTA provided similar findings. PK assessments tracked PD profiles showing increased plasma concentrations of ticagrelor and its major metabolite in CKD compared to non-CKD patients.

CONCLUSION

In patients with DM, although ticagrelor maintenance dose regimens (60 mg and 90 mg) yield potent P2Y12 inhibition, levels of platelet reactivity tended to be higher and subject to broader variability in non-CKD compared with CKD patients.

CLINICAL TRIAL REGISTRATION

http://www.clinicaltrials.gov Unique Identifier: NCT02539160.

Impact of chronic kidney disease on platelet aggregation in patients with acute coronary syndrome

AIMS

Chronic kidney disease (CKD) is associated with increased thrombotic events and seems to influence platelet reactivity. Conflicting results have been published on platelet response in CKD patients with stable coronary artery disease. The aim of our study was to investigate the impact of CKD on platelet aggregation in acute coronary syndrome (ACS) patients receiving dual antiplatelet therapy, included the more potent P2Y12 inhibitors.

METHODS

We enrolled 206 patients with ACS, divided in two groups, according to the presence or the absence of moderate/severe CKD. Platelet aggregation was performed with light transmission aggregometry and results are expressed as percentage of maximum platelet aggregation. High residual platelet reactivity (HRPR) was defined as maximum platelet aggregation more than 59%.

RESULTS

Patients with CKD [estimate glomerular filtration rate (eGFR) < 60 ml/min/1.73 m, n = 28] were prevalent older, diabetic, had previous coronary revascularization. In these patients, platelet aggregation was significantly higher than in those with eGFR ≥ 60 ml/min/1.73 m (ADP 10 μmol/l: 28.46 ± 26.19 vs. 16.64 ± 12.79, P < 0.001; ADP 20 μmol/l: 30.07 ± 25.89 vs. 17.46 ± 12.82, P < 0.001). HRPR was observed in 4.4% of patients, with higher prevalence in those with eGFR less than 60 ml/min/1.73 m [21.4 vs. 1.7%, P < 0.001, odds ratio (OR) [95% confidence interval (CI)] = 15.91 (3.71-68.17), P < 0.001]. At multivariate analysis, after correction for baseline confounders, eGFR [adjusted OR (95% CI) = 0.95 (0.91-0.98), P = 0.007], together with the use of clopidogrel [adjusted OR (95% CI) = 23.59 (4.01-138.82), P < 0.001], emerged as determinants of HRPR.

CONCLUSION

In patients with ACS receiving dual antiplatelet therapy, CKD is associated with an increasing ADP-induced platelet aggregation and higher prevalence of HRPR, which is mainly correlated to clopidogrel use.

Impact of renal function on residual platelet reactivity and clinical outcomes in patients with acute coronary syndrome treated with clopidogrel

BACKGROUND

Chronic kidney disease (CKD) is a common comorbidity in patients with acute coronary syndrome (ACS) and may potentially influence platelet function.

HYPOTHESIS

We explored the influence of renal function on platelet reactivity to investigate whether high residual platelet reactivity (HRPR) is associated with cardiovascular events.

METHODS

ACS patients treated with aspirin and clopidogrel were prospectively enrolled. Patients were categorized into two groups on the basis of baseline estimated glomerular filtration rate (eGFR): non-CKD (eGFR ≥60 mL/min/1.73 m2 ) and CKD (eGFR <60 mL/min/1.73 m2 ). Platelet function was measured by thromboelastography ≥5 days after maintenance dual antiplatelet therapy. Major adverse clinical events (MACEs) were collected at 1 year after discharge.

RESULTS

There were 282 non-CKD patients and 212 CKD patients. A significant difference in median MAADP value was observed between the two groups (15.0 mm vs. 31.3 mm, p < .001). HRPR was more prevalent in the CKD group than the non-CKD group (27.4% vs 9.6%, p < .001). At 1-year follow-up, the incidence of MACEs was significantly higher for those with both CKD and HRPR compared with those with either CKD or HRPR (37.9% vs. 18.5%, p < .001). The relationship between HRPR and MACEs was consistent across CKD strata without evidence of interaction. Adding platelet reactivity to eGFR improved the model with area under the curve increasing from 0.703 to 0.734.

CONCLUSION

In patients with ACS, the risk of HRPR increased with declining eGFR. Both CKD and HRPR were associated with MACEs at 1-year follow-up.

Impact of Chronic Kidney Disease and Platelet Reactivity on Clinical Outcomes Following Percutaneous Coronary Intervention

We investigated the interaction between chronic kidney disease (CKD) and high platelet reactivity (HPR) in determining long-term clinical outcomes following elective PCI for stable coronary artery disease (CAD). A total of 500 patients treated with aspirin and clopidogrel were divided based on the presence of CKD (defined as glomerular filtration rate of < 60 ml/min/1.73 m²) and HPR (defined as a P2Y12 reaction unit value ≥ 240 at VerifyNow assay). Primary endpoint was the occurrence of major adverse clinical events (MACE) at 5 years. Patients with both CKD and HPR showed the highest estimates of MACE (25.6%, p = 0.005), all-cause death (17.9%, p = 0.004), and cardiac death (7.7%, p = 0.004). The combination of CKD and HPR was an independent predictor of MACE (HR 3.12, 95% CI 1.46-6.68, p = 0.003). In conclusion, the combination of CKD and HPR identifies a cohort of patients with the highest risk of MACE at 5 years.

Impact of Diabetes Mellitus and Chronic Kidney Disease on Cardiovascular Outcomes and Platelet P2Y12 Receptor Antagonist Effects in Patients With Acute Coronary Syndromes: Insights From the PLATO Trial

Background

There are limited data on how the combination of diabetes mellitus (DM) and chronic kidney disease (CKD) affects cardiovascular outcomes as well as response to different P2Y₁₂ receptor antagonists, which represented the aim of the present investigation.

Methods and Results

In this post hoc analysis of the PLATO (Platelet Inhibition and Patient Outcomes) trial, which randomized acute coronary syndrome patients to ticagrelor versus clopidogrel, patients (n=15 108) with available DM and CKD status were classified into 4 groups: DM+/CKD+ (n=1058), DM+/CKD− (n=2748), DM−/CKD+ (n=2160), and DM−/CKD− (n=9142). The primary efficacy end point was a composite of cardiovascular death, myocardial infarction, or stroke at 12 months. The primary safety end point was PLATO major bleeding. DM+/CKD+ patients had a higher incidence of the primary end point compared with DM−/CKD− patients (23.3% versus 7.1%; adjusted hazard ratio 2.22; 95% CI 1.88–2.63; P<0.001). Patients with DM+/CKD− and DM−/CKD+ had an intermediate risk profile. The same trend was shown for the individual components of the primary end point and for major bleeding. Compared with clopidogrel, ticagrelor reduced the incidence of the primary end point consistently across subgroups (P‐interaction=0.264), but with an increased absolute risk reduction in DM+/CKD+. The effects on major bleeding were also consistent across subgroups (P‐interaction=0.288).

Conclusions

In acute coronary syndrome patients, a gradient of risk was observed according to the presence or absence of DM and CKD, with patients having both risk factors at the highest risk. Although the ischemic benefit of ticagrelor over clopidogrel was consistent in all subgroups, the absolute risk reduction was greatest in patients with both DM and CKD.

Clinical Trial Registration

URL: http://www.clinicatrials.gov. Unique identifier: NCT00391872.

Incidence, Patterns, and Impact of Dual Antiplatelet Therapy Cessation Among Patients With and Without Chronic Kidney Disease Undergoing Percutaneous Coronary Intervention: Results From the PARIS Registry (Patterns of Non-Adherence to Anti-Platelet Regimens in Stented Patients)

BACKGROUND

Patients with chronic kidney disease (CKD) experience high rates of ischemic and bleeding events after percutaneous coronary intervention (PCI), complicating decisions surrounding dual antiplatelet therapy (DAPT). This study aims to determine the pattern and impact of various modes of DAPT cessation for patients with CKD undergoing PCI.

METHODS AND RESULTS

Patients from the PARIS registry (Patterns of Non-Adherence to Anti-Platelet Regimens in Stented Patients) were grouped based on the presence of CKD defined as creatinine clearance <60 mL/min. After index PCI, time and mode of DAPT cessation (discontinuation, interruption, and disruption) and clinical outcomes (major adverse cardiac events, stent thrombosis, myocardial infarction, and major bleeding [Bleeding Academic Research Consortium type 3 or 5]) were reported. Over 2 years, patients with CKD (n=839) had higher adjusted risks for death (hazard ratio, 3.16; 95% confidence interval, 2.26-4.41), myocardial infarction (hazard ratio, 2.43; 95% confidence interval, 1.65-3.57), and major bleeding (hazard ratio, 2.21; 95% confidence interval, 1.53-3.19) compared with patients without CKD (n=3745). Rates of DAPT discontinuation within the first year after PCI and disruption were significantly higher for patients with CKD. However, DAPT interruption occurred with equal frequency. Associations between DAPT cessation mode and subsequent risk were not modified by CKD status. Findings were unchanged after propensity matching.

CONCLUSIONS

Patients with CKD display high and comparable risks for both ischemic and bleeding events after PCI. Physicians are more likely to discontinue DAPT within the first year after PCI among patients with CKD, likely reflecting clinical preferences to avoid bleeding. Risks after DAPT cessation, irrespective of underlying mode, are not modified by the presence or absence of CKD.

Deleting Death and Dialysis: Conservative Care of Cardio-Vascular Risk and Kidney Function Loss in Chronic Kidney Disease (CKD)

The uremic syndrome, which is the clinical expression of chronic kidney disease (CKD), is a complex amalgam of accelerated aging and organ dysfunctions, whereby cardio-vascular disease plays a capital role. In this narrative review, we offer a summary of the current conservative (medical) treatment options for cardio-vascular and overall morbidity and mortality risk in CKD. Since the progression of CKD is also associated with a higher cardio-vascular risk, we summarize the interventions that may prevent the progression of CKD as well. We pay attention to established therapies, as well as to novel promising options. Approaches that have been considered are not limited to pharmacological approaches but take into account lifestyle measures and diet as well. We took as many randomized controlled hard endpoint outcome trials as possible into account, although observational studies and post hoc analyses were included where appropriate. We also considered health economic aspects. Based on this information, we constructed comprehensive tables summarizing the available therapeutic options and the number and kind of studies (controlled or not, contradictory outcomes or not) with regard to each approach. Our review underscores the scarcity of well-designed large controlled trials in CKD. Nevertheless, based on the controlled and observational data, a therapeutic algorithm can be developed for this complex and multifactorial condition. It is likely that interventions should be aimed at targeting several modifiable factors simultaneously.

Impact of chronic kidney disease on platelet P2Y12 receptor signalling in patients with type 2 diabetes mellitus

Supplementary Material to this article is available online at www.thrombosis-online.com.

The impact of renal function on platelet reactivity and clinical outcome in patients undergoing percutaneous coronary intervention with stenting

Patients with chronic kidney disease (CKD) have an increased risk of cardiovascular disease. Previous studies have suggested that patients with CKD have less therapeutic benefit of antiplatelet therapy. However, the relation between renal function and platelet reactivity is still under debate. On-treatment platelet reactivity was determined in parallel by ADP- and AA-induced light transmittance aggregometry (LTA) and the VerifyNow® System (P2Y12 and Aspirin) in 988 patients on dual antiplatelet therapy, undergoing elective coronary stenting. Patients were divided into two groups according to the presence or absence of moderate/severe CKD (GFR<60 ml/min/1.73 m2). Furthermore, the incidence of all-cause death, non-fatal acute myocardial infarction, stent thrombosis and stroke at one-year was evaluated. Patients with CKD (n=180) had significantly higher platelet reactivity, regardless of the platelet function test used. Patients with CKD more frequently had high on-clopidogrel platelet reactivity (HCPR) and high on-aspirin platelet reactivity (HAPR) regardless of the platelet function test used. After adjustment for potential confounders, this was no longer significant. The event-rate was the highest in patients with both high on-treatment platelet reactivity (HPR) and CKD compared to those with neither high on-treatment platelet reactivity nor CKD. In conclusion, the magnitude of platelet reactivity as well as the incidence of HPR was higher in patients with CKD. However, since the incidence of HPR was similar after adjustment, a higher rate of co-morbidities in patients with CKD might be the major cause for this observation rather than CKD itself. CKD-patients with HCPR were at the highest risk of long-term cardiovascular events.

Clinical Trial Registration: www.clinicaltrials.gov: NCT00352014.

Renal Dysfunction: How to Think About That in Acute Coronary Syndromes

PURPOSE OF REVIEW

Reduction of kidney function and heart disease frequently coexisted in the seam patient. The relation between renal and heart function is quite complex and bring out some unresolved questions about diagnosis (mostly related to the biomarkers levels interpretation), pharmacological therapy (mostly related to drugs kinetics and efficacy), and non-pharmacological therapy.

RECENT FINDINGS

Patients with kidney dysfunction (KD) are frequently excluded and underrepresented in the large trials. It is well-known that coronary revascularization reduces mortality also in KD patients presenting with acute coronary syndrome. However, acute kidney injury (AKI), primarily related at contrast medium administration, is worse prognosis. For this reason, prevention, early diagnosis, and effective therapy of ACK are key elements in assistance of these patients. In this context, recently, some new biomarkers of renal function have been proposed. Frequently, patients with acute coronary syndromes and kidney disease are undertreated, worsening their prognosis. Undertreatment and comorbidities associated with renal dysfunction explain the higher mortality of these patients.

Pharmacokinetic and Pharmacodynamic Responses to Clopidogrel: Evidences and Perspectives

Clopidogrel has significantly reduced the incidence of recurrent atherothrombotic events in patients with acute coronary syndrome (ACS) and in those undergoing percutaneous coronary intervention (PCI). However, recurrence events still remain, which may be partly due to inadequate platelet inhibition by standard clopidogrel therapy. Genetic polymorphisms involved in clopidogrel’s absorption, metabolism, and the P2Y12 receptor may interfere with its antiplatelet activity. Recent evidence indicated that epigenetic modification may also affect clopidogrel response. In addition, non-genetic factors such as demographics, disease complications, and drug-drug interactions can impair the antiplatelet effect of clopidogrel. The identification of factors contributing to the variation in clopidogrel response is needed to improve platelet inhibition and to reduce risk for cardiovascular events. This review encompasses the most recent updates on factors influencing pharmacokinetic and pharmacodynamic responses to clopidogrel.

Impaired P2Y12 inhibition by clopidogrel in kidney transplant recipients: results from a cohort study

Background

Cardiovascular complications represent a major cause of morbidity and mortality for patients who received kidney transplantation (KT). However, the impact of KT and chronic immunosuppression on platelet response to clopidogrel in patients undergoing coronary or peripheral revascularization procedures remains unclear. This cohort study compares platelet responsiveness to clopidogrel as assessed byvasodilator-stimulated phosphoprotein (VASP) phosphorylation.

Methods

The study population was divided between chronic kidney disease (CKD) patients who underwent KT (n = 36) and non-transplanted CKD patients (control group, n = 126). Patients were on maintenance antiplatelet therapy with clopidogrel 75 mg daily for at least 8 days. The mean platelet reactivity index (PRI) VASP values and the prevalence of high on-treatment platelet reactivity (HPR, defined as PRI VASP ≥61 %) were compared.

Results

The mean PRI VASP value was significantly higher in the transplant group (60.1 ± 3 vs 51.2 ± 1.6 %; p=0.014). HPR was significantly more common in the transplant group on clopidogrel maintenance therapy (58 vs. 31 %; p = 0.011). KT was the only independent predictor of HPR (odds ratio: 2.6; 95 % confidence interval: 1.03–6.27, p = 0.03). The effect of treatment with calcineurin inhibitors on clopidogrel response could not be analyzed separately from the kidney transplant status.

Conclusions

KT is associated with an increased prevalence of HPR. Our results suggest that plateletfunction tests may be clinically useful for the management of this specific population.

Favorable outcomes in octogenarians treated with bioresorbable polymer drug-eluting stent

AIM

As a result of a higher prevalence of comorbidities, elderly adults are often underrepresented in clinical trials, and more often experience complications during percutaneous coronary intervention. Our aim was to evaluate clinical outcomes of patients older than 80 years, compared with their younger counterparts, when bioresorbable polymer biolimus A9 drug-eluting stent is used for their treatment.

METHODS

The prospective, observational e-Nobori registry was created to validate the safety and efficacy of bioresorbable polymer drug-eluting stent in unselected patients. The primary end-point of the study was freedom from target lesion failure defined as a composite of cardiac death, target vessel-related myocardial infarction and clinically-driven target lesion revascularization at 1 year.

RESULTS

There were 781 (7.8%) octogenarians, they were less frequently male (62% vs 77%; P < 0.0001) and more often presented as acute coronary syndrome (44% vs 39%; P = 0.0182). The index percutaneous coronary intervention success was lower in the elderly patients (98% vs 99%; P = 0.0398). One-year follow up was completed for 97% of the elderly patients and 99% of the younger patients. The difference in target lesion failure (3.33% vs 2.83%; log-rank P = 0.0114) was mainly driven by increased mortality in octogenarians (3.73% vs 1.47%; P < 0.0001). Elderly patients had more bleeding and vascular complications (2.67% vs 1.05%; P = 0.0001).

CONCLUSIONS

Despite advanced age, multiple comorbidities and complexity of treated lesions, clinical outcomes are favorable in octogenarians treated by bioresorbable polymer biolimus A9 drug-eluting stent. Geriatr Gerontol Int 2016; 16: 1246-1253.

Impact of chronic kidney disease on long-term ischemic and bleeding outcomes in medically managed patients with acute coronary syndromes: Insights from the TRILOGY ACS Trial

AIMS

We aimed to study the relationship of chronic kidney disease stages with long-term ischemic and bleeding outcomes in medically managed acute coronary syndrome patients and the influence of more potent antiplatelet therapies on platelet reactivity by chronic kidney disease stage.

METHODS AND RESULTS

We estimated creatinine clearance for 8953 medically managed acute coronary syndrome patients enrolled in the Targeted Platelet Inhibition to Clarify the Optimal Strategy to Medically Manage Acute Coronary Syndromes trial. Patients were classified by chronic kidney disease stage: normal renal function/mild (creatinine clearance >60 mL/min); moderate (creatinine clearance 30-60 mL/min); severe (creatinine clearance <30 mL/min). Kaplan-Meier event rates through 30 months were evaluated for ischemic (cardiovascular death, myocardial infarction or stroke; primary end point) and bleeding (Global Use of Strategies to Open Occluded Coronary Arteries and Thrombolysis In Myocardial Infarction bleeding) outcomes by chronic kidney disease stage and treatment allocation (prasugrel vs. clopidogrel) within each stage. Adjusted hazard ratios (95% confidence intervals) for moderate and for severe chronic kidney disease vs. normal/mild chronic kidney disease were estimated. Platelet reactivity at 30 days was assessed in a subset of patients (n = 1947). The majority of patients were in the normal/mild chronic kidney disease group (67%), followed by moderate chronic kidney disease (29%) and severe chronic kidney disease (4%). The incidence of ischemic and bleeding outcomes increased sharply across chronic kidney disease stages and no significant treatment interactions were observed. The adjusted risk of the primary end point increased across chronic kidney disease stages (moderate vs. normal/mild: hazard ratio 1.26; 95% confidence interval 1.09-1.46; severe vs. normal/mild: hazard ratio 1.60; 95% confidence interval 1.25-2.04). Platelet reactivity was lower in patients treated with prasugrel compared with clopidogrel, across all three chronic kidney disease stages.

CONCLUSIONS

Among medically managed acute coronary syndrome patients, the long-term risks of ischemic and bleeding outcomes increased markedly with worse chronic kidney disease stages. Despite lower platelet reactivity of prasugrel compared with clopidogrel, no treatment interactions for ischemic and bleeding outcomes were observed.

Prevalence and Impact of High Platelet Reactivity in Chronic Kidney Disease

Background—

Chronic kidney disease (CKD) is associated with increased rates of adverse events after percutaneous coronary intervention. We sought to determine the impact of CKD on platelet reactivity in clopidogrel-treated patients and whether high platelet reactivity (HPR) confers a similar or differential risk for adverse events among patients with CKD and non-CKD.

Methods and Results—

We performed a post hoc analysis of the Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents (ADAPT-DES) registry, which included 8582 patients undergoing percutaneous coronary intervention with drug-eluting stents and platelet function testing using the VerifyNow assay. We compared HPR and its impact on ischemic and bleeding events >2 years among patients with CKD and non-CKD. Patients with CKD (n=1367) were older, more often female, diabetic, and had lower ejection fraction compared with their non-CKD counterparts (n=7043). Although HPR prevalence increased with worsening renal function in unadjusted analyses, these associations were no longer present after adjustment. Major adverse cardiac event rates at 2 years among those without CKD or HPR, HPR alone, CKD alone, and both CKD and HPR were 9.0%, 11.2%, 13.3%, and 17.5%, respectively ( P <0.001). Associations between HPR and adverse events were uniform across CKD strata without evidence of interaction.

Conclusions—

HPR is more common among those with versus without CKD, an association that is attributable to confounding risk factors that are more prevalent in CKD. The impact of HPR on ischemic and bleeding events is similar irrespective of CKD status.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00638794.

Adhesion and activation of platelets from subjects with coronary artery disease and apparently healthy individuals on biomaterials

On the basis of the clinical studies in patients with coronary artery disease (CAD) presenting an increased percentage of activated platelets, we hypothesized that hemocompatibility testing utilizing platelets from healthy individuals may result in an underestimation of the materials' thrombogenicity. Therefore, we investigated the interaction of polymer-based biomaterials with platelets from CAD patients in comparison to platelets from apparently healthy individuals. In vitro static thrombogenicity tests revealed that adherent platelet densities and total platelet covered areas were significantly increased for the low (polydimethylsiloxane, PDMS) and medium (Collagen) thrombogenic surfaces in the CAD group compared to the healthy subjects group. The area per single platelet-indicating the spreading and activation of the platelets-was markedly increased on PDMS treated with PRP from CAD subjects. This could not be observed for collagen or polytetrafluoroethylene (PTFE). For the latter material, platelet adhesion and surface coverage did not differ between the two groups. Irrespective of the substrate, the variability of these parameters was increased for CAD patients compared to healthy subjects. This indicates a higher reactivity of platelets from CAD patients compared to the healthy individuals. Our results revealed, for the first time, that utilizing platelets from apparently healthy donors bears the risk of underestimating the thrombogenicity of polymer-based biomaterials.

Dipstick proteinuria is an independent predictor of high on treatment platelet reactivity in patients on clopidogrel, but not aspirin, admitted for major adverse cardiovascular events

The effectiveness of aspirin and clopidogrel in patients with chronic kidney disease (CKD) suffering from acute cardiovascular events is unclear. High on treatment platelet reactivity (HTPR) has been associated with worse outcomes. Here, we assessed the association of dipstick proteinuria (DP) and renal function on HTPR and clinical outcomes. Retrospective cohort analysis of 261 consecutive, non-dialysis patients admitted for Major Adverse Cardiovascular Events (MACE) that had VerifyNow P2Y12 and VerifyNow Aspirin assays performed. HTPR was defined as P2Y12 reactivity unit (PRU) > 208 for clopidogrel and aspirin reaction units (ARU) > 550 for aspirin. Renal function was classified based on the estimated glomerular filtration rate (eGFR), and dipstick proteinuria was defined as ≥ 30 mg/dl of albumin detected on a spot analysis. All cause mortality, readmissions, and cardiac catheterizations were reviewed over 520 days. In patients on clopidogrel (n = 106), DP was associated with HTPR, independent of eGFR, diabetes mellitus, smoking or use of proton pump inhibitor (AOR = 4.76, p = 0.03). In patients with acute coronary syndromes, HTPR was associated with more cardiac catheterizations (p = 0.009) and readmissions (p = 0.032), but no differences in in-stent thrombosis or re-stenosis were noted in this cohort. In patients on aspirin (n = 155), no associations were seen between DP and HTPR. However, all cause mortality was significantly higher with HTPR in this group (p = 0.038). In this cohort, DP is an independent predictor of HTPR in patients on clopidogrel, but not aspirin, admitted to the hospital for MACE.