Optimal Duration of Dual Antiplatelet Therapy After DES Implantation: A Meta-Analysis of 11 Randomized Trials

Antithrombotic therapy following lower extremity endovascular revascularization: The results of a survey of vascular specialists

Objective

Antithrombotic therapy improves endovascular intervention outcomes for peripheral artery disease. However, there are limited data guiding the choice and duration of these adjuvant therapies. Thus, we explored current antithrombotic prescribing preferences among vascular interventionalists, hypothesizing that there are varied and inconsistent treatment practices among providers.

Methods

We developed and distributed a de-identified RedCap survey via Twitter and email to Vascular Quality Initiative members (February 2023). Multiple-choice questions queried antithrombotic agents and treatment durations for a clinical vignette (a claudicant on 81 mg aspirin and statin) with different arterial disease locations (iliac, femoropopliteal, or tibial vessels) and different revascularization strategies (angioplasty or stenting, with and without drug-coating). Antithrombotic options included monotherapies with antiplatelet agents or low-dose rivaroxaban; dual therapies with aspirin combined with a P2Y12 inhibitor (dual antiplatelet therapy, DAPT) or low-dose rivaroxaban (dual pathway inhibition or DPI); or triple therapy with aspirin, a P2Y12 inhibitor, and low-dose rivaroxaban. Options for therapy duration included 30, 90, 180, and 365 days, or indefinitely.

Results

There were 199 respondents (17% female, 68% White race, 63% academic, 88% vascular surgery). Across all treatment scenarios, respondents selected DAPT (n = 171/199; 86%) in at least one revascularization scenario, followed by aspirin monotherapy (n = 83/199; 42%) and DPI (n = 49/199; 25%). Therapy choice did differ by both anatomic location and revascularization strategy (P < .05). DAPT was most selected following femoropopliteal revascularization (n = 165/199, 83%) and bare metal stenting (n = 162/198, 82%). However, aspirin monotherapy was most selected following iliac level revascularization (n = 52/197; 26%) and following percutaneous transluminal angioplasty at any level (n = 51/182; 28%). DPI was most selected following tibial revascularization (n = 39/184; 21%) and following percutaneous transluminal angioplasty (n = 38/182; 21%). Among those who selected DAPT, the 90-day (n = 99/171; 58%) duration was preferred. Those who selected DPI favored indefinite treatment durations (n = 34/49; 69%). Indefinite DAPT and DPI therapy were more commonly selected for distal level revascularization (P < .05). Rivaroxaban utilization was limited secondary to cost (n = 108/178; 61%), lack of demonstrated effectiveness (n = 75/178; 42%), and concern for safety and bleeding (n = 27/178; 15%).

Conclusions

Following lower extremity endovascular treatment of peripheral artery disease, a 90-day duration of DAPT remains the most commonly selected antithrombotic regimen despite the emergence of DPI as an evidence-based antithrombotic therapy. The variability in provider preferred antithrombotic agent and treatment duration emphasizes the need for high-quality evidence for the medical optimization of revascularization outcomes.

Extended dual antiplatelet therapy following percutaneous coronary intervention in clinically important patient subgroups: a systematic review and meta-analysis

BACKGROUND

Dual antiplatelet therapy (DAPT) is routinely given to patients after percutaneous coronary intervention (PCI) with stenting; however, optimal duration remains uncertain in some situations. We assessed the benefits and harms of extending DAPT beyond 1 year after PCI in clinically important patient subgroups.

METHODS

We conducted a systematic review and meta-analysis. We searched electronic databases (Embase, MEDLINE, PubMed, Cochrane Library) and grey literature (from inception to Nov. 5, 2021) and included randomized controlled trials (RCTs) of extended DAPT (> 12 mo) compared with DAPT for 6-12 months following PCI with stenting. The primary outcome was death (all cause, cardiovascular, noncardiovascular); secondary outcomes included major adverse cardiovascular and cerebrovascular events, myocardial infarction (MI), stroke, stent thrombosis and bleeding. Subgroups were based on prespecified patient characteristics (prior MI, acute coronary syndrome [ACS], diabetes mellitus, age, smoking status). Data were analyzed by random-effects pairwise meta-analysis.

RESULTS

We identified 9 RCTs that provided subgroup data. We found that extended DAPT reduced the risk of MI and stent thrombosis but increased the risk of bleeding, compared with standard DAPT, with no difference in the risk of all-cause death (relative risk [RR] 1.07, 95% confidence interval [CI] 0.80-1.42) or cardiovascular death (RR 0.98, 95% CI 0.74-1.30). We found that patients with a prior MI, with ACS at presentation, without diabetes or aged younger than 75 years may derive the most benefit from extended DAPT. Among patients who received extended DAPT, the risk of all-cause death was significantly increased among those with no prior MI (RR 1.64, 95% CI 1.08-2.24), whereas there was no significant difference in the risk of all-cause death between standard and extended DAPT for patients with ACS (RR 1.20, 95% CI 0.51-2.83), with diabetes (RR 1.27, 95% CI 0.86-1.89), aged older than 75 years (RR 1.32, 95% CI 0.39-4.54) or who smoked (RR 0.90, 95% CI 0.42-1.92). Similar results were found for cardiovascular death, where data were available.

INTERPRETATION

Patients with a previous MI with ACS at presentation, without diabetes, or aged younger than 75 years may derive the most benefit from extended DAPT. These findings support the need for careful selection of patients who may benefit most from extended DAPT.

STUDY REGISTRATION

PROSPERO no. CRD42018082587.

Gender differences with short-term vs 12 months dual antiplatelet therapy in patients with acute coronary syndrome treated with the COMBO dual therapy stent: 2-years follow-up results of the REDUCE trial

BACKGROUND

Gender differences in the thrombotic and bleeding risk have been suggested to condition the benefits of antithrombotic therapies in Acute Coronary Syndrome (ACS) patients, and mainly among those undergoing percutaneous coronary interventions with drug eluting stents (DES). The impact of gender on the optimal duration of dual antiplatelet therapy (DAPT) in ACS patients is still unexplored and was, therefore, the aim of the present sub-study.

METHODS

REDUCE was a prospective, multicenter, randomized investigator-initiated study designed to enroll 1500 ACS patients after treatment with the COMBO Dual Stent Therapy, based on a noninferiority design. Patients were randomized in a 1:1 fashion to either 3 or 12 months of DAPT. Primary study endpoint was a composite of all-cause mortality, myocardial infarction, definite/probable stent thrombosis (ST), stroke, target-vessel revascularization (TVR) and bleedings (BARC II, III, V) at 12 months. Secondary endpoints were cardiovascular mortality and the individual components of the primary endpoint within 24 months.

RESULTS

From June 2014 to May 2016 300 women and 1196 men were included in the study. Among them, 43.7% of females and 51.9% of males were assigned to the 3 months DAPT treatment. Baseline characteristics were well matched between the two arms, with the exception of a lower rate of TIMI flow < 3 (p = 0.04), lower systolic blood pressure (p = 0.05) and use of spironolactone (p = 0.006) among women and a more advanced age (p = 0.05) among men receiving a short-term DAPT. At a mean follow-up of 525 (± 198) days, no difference in the primary endpoint was observed according to DAPT duration in both females [6.9% vs 5.9%, HR (95% CI) = 1.19 (0.48-2.9), p = 0.71] and males [8.2% vs 9%, HR (95% CI) = 0.92 (0.63-1.35), p = 0.67; p INT = 0.20]. Results were confirmed after correction for baseline differences [females: adjusted HR (95% CI) = 1.12 (0.45-2.78), p = 0.81; males: adjusted HR (95% CI) = 0.90 (0.61-1.32), p = 0.60]. Comparable rates of survival, thrombotic (MI, stent thrombosis, TVR, stroke) and bleeding events were observed with the two DAPT strategies, with no impact of gender.

CONCLUSIONS

The present study shows that among ACS patients randomized in the REDUCE trial, a 3 months DAPT strategy offers comparable results as compared to a standard 12 months DAPT at 2-years follow-up in both male and female gender.

Impact of age on the comparison between short-term vs 12-month dual antiplatelet therapy in patients with acute coronary syndrome treated with the COMBO dual therapy stent: 2-Year follow-up results of the REDUCE trial

BACKGROUND AND AIMS

The impact of advanced age on the optimal duration of dual antiplatelet therapy (DAPT) in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary revascularization (PCI) is still greatly debated. Therefore, the aim of the present sub-analysis of the REDUCE trial was to assess the impact of age on the comparison between a short 3 months vs standard 12 months DAPT in ACS patients treated with the COMBO Dual Stent Therapy.

METHODS

The REDUCE trial is a prospective, multicenter, investigator-initiated study that randomized ACS patients undergoing PCI with the COMBO drug eluting stent to either 3 or 12 months of DAPT. The study population was divided according to age (<or ≥ 75 years). Primary study endpoint was a composite of all-cause mortality, myocardial infarction, definite/probable stent thrombosis (ST), stroke, target-vessel revascularization (TVR) and bleeding (BARC II, III, V) at 12 months. Secondary endpoints were cardiovascular mortality and the individual components of the primary endpoint within 24 months.

RESULTS

From June 2014 to May 2016, 1496 patients were included in the study, of whom 205 (13.7%) ≥75 years of age. Among them, 50.7% of the elderly and 50.2% of younger patients were assigned to the 3-month DAPT treatment. Baseline characteristics were well matched between the two arms, except for a higher rate of males (p=0.02) and a reduced number of lesions on the right coronary artery (p=0.02) in elderly patients treated for the short DAPT duration. Median follow-up was 682.5 days [IQR:667-731]. At 12 months, no difference in the primary endpoint was observed according to DAPT duration in both patients aged ≥75 years (22.1% vs 18.8%, HR [95%CI] = 1.6 [0.73-3.5], p=0.24) and younger ones (9.7% vs 10.9%, HR [95%CI] = 0.85 [0.59-1.27], p=0.44; p INT = 0.15). Results were confirmed after correction for baseline differences among the elderly (adjusted HR [95%CI] = 1.7 [0.75-3.9], p=0.21). Comparable rates of survival, thrombotic (MI, stent thrombosis, TVR, stroke) and bleeding events were observed with the two DAPT strategies, with no impact of age.

CONCLUSIONS

The present study shows that among ACS patients randomized in the REDUCE trial, a 3-month DAPT strategy was comparable to a standard 12-month DAPT at a 2-year follow-up for both ischemic and bleeding endpoints, in elderly and younger patients. Thus, despite presenting the limitations of a subgroup analysis, our study strengthens the feasibility of a shorter DAPT duration even among high-risk subsets of ACS patients.

Poly (l-lactic acid) bioresorbable scaffolds versus metallic drug-eluting stents for the treatment of coronary artery disease: A meta-analysis of 11 randomized trials

BACKGROUND

Bioresorbable vascular scaffolds (BVS) have been proposed for overcoming the long-term limitations of permanent metallic stents, while theoretically warranting similar advantages in plaque stabilization and anti-restenotic drug delivery in the early postrevascularization phase. However, increased rates of malapposition, restenosis, or thrombosis have emerged from initial trials with BVS, that were nevertheless underpowered for the evaluation of the real outcome benefits of these coronary devices. The recent completion of newer randomized clinical trials paves the way to the present meta-analysis, aiming at the comparison of Poly (l-Lactic acid) BVS (PLLA-BVS) versus metallic drug-eluting stents (DES) in the treatment of coronary stenoses.

METHODS

Literature and main scientific session abstracts were searched for randomized clinical trials (RCTs) comparing drug-eluting BVS versus metallic DES for the treatment of coronary artery disease (CAD). The primary efficacy endpoint was mortality, secondary endpoints were cardiovascular death, myocardial infarction, target lesion revascularization (TLR), stent thrombosis and the composite of device-oriented target lesion failure (TLF).

RESULTS

We included 11 randomized trials, for a total population of 10,707 patients, 54.5% treated with BVS. The major indication for PCI was stable CAD, whereas acute coronary syndrome represented 30% of the patients. At a mean follow-up of 2.64 years (1-5 years), mortality occurred in 2.71% of the patients, with no difference according to the type of implanted stent (OR[95%CI] = 0.94 [0.74, 1.20], p = .62). No interaction was observed according to patients' risk profile or the rate of diabetes and ACS. However, a significant increase in myocardial infarction, stent thrombosis, TLR and TLF was observed with BVS as compared to DES.

CONCLUSIONS

The present meta-analysis provides the most updated data on the use of PLLA-BVS for the treatment of CAD. We documented a poorer performance of these new coronary devices, as compared to new generation metallic DES, being associated with an increased rate of recurrent cardiovascular events. However, such ischemic complications did not impact on mortality, with a comparable survival independently from the type of stent.

Meta-analysis of noninferiority and equivalence trials: ignoring trial design leads to differing and possibly misleading conclusions

OBJECTIVE

The objective of the study is to examine the analytic approach of meta-analyses that include noninferiority or equivalence (NI/EQ) trials.

STUDY DESIGN AND SETTING

We used Scopus to identify meta-analyses including NI/EQ trials. We extracted data from the meta-analyses and their included randomized clinical trials (RCTs). We used the RCT's NI/EQ margins to reinterpret the results of the meta-analyses, assessed for risk of biases unique to NI/EQ trials, and evaluated the consistency of the meta-analysis interpretation when using NI/EQ margins.

RESULTS

We identified 38 unique meta-analyses including 515 RCTs, of which 125 (24.3%) were NI/EQ trials. Fourteen meta-analyses (36.8%) reported the study design of their included trials, but only one (2.6%) interpreted their pooled estimates using NI/EQ margins and none assessed for risks of bias unique to NI/EQ trials. Nearly all NI/EQ trials (n = 116, 92.8%) included in the meta-analyses reported NI/EQ margins. The meta-analyses of 30 outcomes were reinterpreted using the NI/EQ margins; reinterpretations conflicted with the conclusion of the meta-analyses in most cases (n = 20, 66.7%).

CONCLUSION

Most meta-analyses including NI/EQ trials ignore trial design and do not assess risks of bias unique to NI/EQ studies. Meta-analyses addressing questions previously explored as NI/EQ should conduct an NI/EQ meta-analysis or use clear language when performing standard (i.e., superiority) meta-analyses.

Very short dual antiplatelet therapy after PCI and new DES: a meta-analysis of 5 randomized trials

INTRODUCTION AND OBJECTIVES

Very early (1-3 months) discontinuation of dual antiplatelet therapy (DAPT) has been recently proposed in percutaneous coronary interventions with modern drug-eluting stents (DES), with contrasting results. The aim of the present meta-analysis was to evaluate the prognostic impact of very short DAPT regimens vs the standard 12-month regimen in patients undergoing percutaneous coronary intervention with new DES.

METHODS

Literature and main scientific session abstracts were searched for randomized clinical trials (RCT). The primary efficacy endpoint was mortality, and the primary safety endpoint was major bleeding events. A prespecified analysis was conducted according to the long-term antiplatelet agent.

RESULTS

We included 5 RCTs, with a total of 30 621 patients; 49.97% were randomized to very short (1-3 months) DAPT, followed by aspirin or P2Y₁₂I monotherapy. Shorter DAPT duration significantly reduced the rate of major bleeding (2% vs 3.1%, OR, 0.62; 95%CI, 0.46-0.84; P=.002; Phet=.02), but did not significantly condition overall mortality (1.3% vs 2%, OR, 0.97; 95%CI, 0.73-1.29; P=.84; Phet=.18). The reduction in bleeding events was even more significant in trials randomizing event-free patients at the time of DAPT discontinuation. The occurrence of myocardial infarction and stent thrombosis was similar between shorter vs standard 12-month DAPT.

CONCLUSIONS

Based on the current meta-analysis, a very short (1-3 months) period is associated with a significant reduction in major bleeding compared with the standard 12-month therapy, with no increase in major ischemic events and comparable survival.

Polymer-Free vs. Polymer-Coated Drug-Eluting Stents for the Treatment of Coronary Artery Disease: A Meta-Analysis of 16 Randomized Trials

BACKGROUND

Polymer-coating represents one of components of drug-eluting stents (DES) to have experienced a more intensive technological evolution. Polymer-free DES (PF-DES) have offered promising angiographic results, with earlier complete re-endothelization, potentially reducing the thrombotic risk and offering the option of a shorter antiplatelet therapy. However, contrasting prognostic data have been reported so far with PF-DES. Therefore, the aim of the present study was to perform a comprehensive updated meta-analysis of randomized trials (RCT) comparing the impact of PF-DES vs polymer- coated DES (PC-DES) on clinical outcome.

METHODS

Literature and main scientific session abstracts were searched for RCTs comparing PF-DES vs PC-DES for the treatment of CAD. The primary efficacy endpoint was mortality, secondary endpoints were cardiovascular death, myocardial infarction, target lesion revascularization (TLR) and stent thrombosis.

RESULTS

We included 16 randomized clinical trials, with a total of 15,689 patients, including 50.6% randomized to PF-DES. At a median follow-up of 24 months, PF-DES were associated to a significant reduction in mortality as compared to PC-DES (0.82 [0.68, 0.99], p = .03, I2 = 0%; phet = 0.93). However, no significant benefit was observed in terms of cardiovascular death or major ischemic endpoints (respectively CV death: OR [95% CI] = 0.92 [0.71, 1.18] p = .50, I2 = 0.50; phet = 0.84; MI: OR [95% CI] = 1.08 [0.90, 1.29], p = .42; I2 = 0%, phet = 0.98; TLR: OR [95% CI] = 1.02 [0.78, 1.32], p = .91; I2 = 0.63 phet = 0.0003; ST: OR [95% CI] = 0.98 [0.87, 1.10], p = .72; I2 = 0% phet = 0.64). By meta-regression analysis, the mortality benefits of PF-DES were not conditioned by the rate of diabetes mellitus or acute coronary syndromes.

CONCLUSIONS

Based on the current meta-analysis, PF-DES are associated to a significant reduction in mortality as compared to PC-DES, but not in the occurrence of major ischemic events. Future larger studies are certainly needed to further investigate and confirm our findings, especially in particular subsets of patients, such as those with high bleeding risk or acute myocardial infarction.

Optimal Duration of Dual Antiplatelet Therapy Following Percutaneous Coronary Intervention: An Umbrella Review

BACKGROUND

The optimal duration of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention with stenting requires consideration of patient characteristics, and decision makers require a comprehensive overview of the evidence.

METHODS

We performed an umbrella review of systematic reviews (SRs) of randomized controlled trials of extended DAPT (> 12 months) compared with DAPT for 6 to 12 months after percutaneous coronary intervention with stenting. Outcomes of interest were death, myocardial infarction (MI), stroke, stent thrombosis, major adverse cardiac and cerebrovascular events, bleeding, and urgent revascularization. We aimed to assess the evidence of benefits and harms among clinically important subgroups (eg, elderly patients, those with diabetes, prior MI, acute coronary syndrome). We assessed the quality of the included reviews by use of A Measurement Tool to Assess Systematic Reviews (AMSTAR).

RESULTS

Sixteen SRs involving 8 randomized controlled trials were included. Most scored 7 or more points on the AMSTAR checklist. There was no significant difference in outcomes with extended DAPT compared with 6 months of DAPT in most SRs, with the exception of an increased risk of major bleeding. Compared with 12 months, extended DAPT may reduce the risk of MI and stent thrombosis; however, the findings were not consistent across all reviews. There have been conflicting reports of an increased risk of death with extended DAPT. Few SRs assessed outcomes among patient subgroups.

CONCLUSIONS

Extended DAPT may reduce the risk of MI and stent thrombosis but increase the risk of major bleeding and death. Whether the effects of extended DAPT are consistent across patient subgroups is unclear, and future SRs should address this knowledge gap.

Dual antiplatelet therapy following percutaneous coronary intervention: protocol for a systematic review

INTRODUCTION

Dual antiplatelet therapy (DAPT) is routinely given to patients after percutaneous coronary intervention (PCI) with stenting; however, there is ongoing debate about the optimal duration, especially in specific patient groups. In the proposed systematic review, we intend to assess the optimal duration of DAPT following PCI with stenting, with a focus on clinically relevant patient subgroups.

METHODS AND ANALYSIS

We will perform a comprehensive search of the published literature for randomised controlled trials (RCTs) assessing the benefits and harms of extended DAPT (>12 months) compared with short-term DAPT (6-12 months) following PCI with stenting (bare metal or drug eluting). ClinicalTrials.gov and ICTRP will also be searched to identify ongoing and completed clinical trials. Two independent reviewers will select studies for inclusion, and the risk of bias will be assessed by use of Cochrane's Risk of Bias tool. The primary outcome of interest is death (all-cause, cardiovascular, non-cardiovascular). Secondary outcomes are bleeding (major, minor, gastrointestinal), urgent target vessel revascularisation, major adverse cardiovascular events, myocardial infarction, stroke and stent thrombosis. Subgroup data will be sought for patients with prior myocardial infarction, acute coronary syndrome at presentation and diabetes, and based on smoking status and age group. Data will be analysed by random-effects meta-analysis, and separate analyses will be performed for patient subgroups. Bayesian network meta-analysis will be performed to investigate the effect of individual P2Y12 inhibitors at different DAPT durations longer than 6 months.

ETHICS AND DISSEMINATION

This review will provide a comprehensive overview of the available evidence of the benefits and harms associated with extending DAPT beyond 12 months following PCI with stenting and the effects on clinically important subgroups. The results of this review will inform clinical and policy decisions regarding the optimal treatment duration of DAPT following PCI with stenting.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO no. CRD42018082587.

Impact of Emergent Cervical Carotid Stenting in Tandem Occlusion Strokes Treated by Thrombectomy: A Review of the TITAN Collaboration

Introduction: Endovascular therapy has been shown to be an effective and safe treatment for tandem occlusion. The endovascular therapeutic strategies for tandem occlusions strokes have not been adequately evaluated and the best approach is still controversial. The TITAN (Thrombectomy in TANdem occlusions) registry was a result of a collaborative effort to identify the best therapeutic approach for acute ischemic stroke due to tandem lesion. In this review, we aim to summarize the main findings of the TITAN study and discuss the challenges of treatment for tandem occlusion in the era of endovascular thrombectomy. Methods: A review of the data from the multicenter international observational and non-randomized TITAN registry was performed. The TITAN registry included acute ischemic stroke patients with tandem lesions (proximal intracranial occlusion and cervical carotid artery occlusion or stenosis>90%) who were treated with thrombectomy with or without carotid artery stenting. Results: Prior intravenous thrombolysis and emergent cervical carotid stenting were associated with higher reperfusion (mTICI 2b-3 and mTICI 3) rates at the end of the intervention. Poor outcome did not occur more frequently after stenting than after conservative treatment of the cervical carotid lesion. Emergent carotid stenting with antithrombotic agents and intracranial thrombectomy yielded higher reperfusion rate and good outcome (90 day mRS 0-2) compared to other strategies (carotid artery stenting and thrombectomy without antithrombotic, angioplasty and thrombectomy, or thrombectomy alone). Pretreatment intravenous thrombolysis was not associated with increased risk of hemorrhagic complications. Likewise, periprocedural unfractionated heparin did not modify the efficacy and safety results. Etiology of carotid artery lesion (atherosclerosis vs. dissection) did not emerge as predictor of outcome or recanalization. Conclusion: Emergent stenting of the cervical carotid lesion with antithrombotic agents in conjunction to thrombectomy appears to be the best treatment strategy for acute ischemic strokes with tandem lesions. These findings will be further investigated in the ongoing randomized controlled TITAN trial.

Application of Feedback System Control Optimization Technique in Combined Use of Dual Antiplatelet Therapy and Herbal Medicines

Aim: Combined use of herbal medicines in patients underwent dual antiplatelet therapy (DAPT) might cause bleeding or thrombosis because herbal medicines with anti-platelet activities may exhibit interactions with DAPT. In this study, we tried to use a feedback system control (FSC) optimization technique to optimize dose strategy and clarify possible interactions in combined use of DAPT and herbal medicines.

Methods: Herbal medicines with reported anti-platelet activities were selected by searching related references in Pubmed. Experimental anti-platelet activities of representative compounds originated from these herbal medicines were investigated using in vitro assay, namely ADP-induced aggregation of rat platelet-rich-plasma. FSC scheme hybridized artificial intelligence calculation and bench experiments to iteratively optimize 4-drug combination and 2-drug combination from these drug candidates.

Results: Totally 68 herbal medicines were reported to have anti-platelet activities. In the present study, 7 representative compounds from these herbal medicines were selected to study combinatorial drug optimization together with DAPT, i.e., aspirin and ticagrelor. FSC technique first down-selected 9 drug candidates to the most significant 5 drugs. Then, FSC further secured 4 drugs in the optimal combination, including aspirin, ticagrelor, ferulic acid from DangGui, and forskolin from MaoHouQiaoRuiHua. Finally, FSC quantitatively estimated the possible interactions between aspirin:ticagrelor, aspirin:ferulic acid, ticagrelor:forskolin, and ferulic acid:forskolin. The estimation was further verified by experimentally determined Combination Index (CI) values.

Conclusion: Results of the present study suggested that FSC optimization technique could be used in optimization of anti-platelet drug combinations and might be helpful in designing personal anti-platelet therapy strategy. Furthermore, FSC analysis could also identify interactions between different drugs which might provide useful information for research of signal cascades in platelet.

Impact of anticoagulation strategy with bivalirudin or heparin on nonaccess site bleeding in percutaneous coronary interventions: A meta-analysis of randomized trials

BACKGROUND

Transradial approach has significantly decreased the rate of access site bleeding in patients undergoing percutaneous coronary interventions (PCI), therefore potentially mitigating the benefits offered by bivalirudin in lowering major bleeding complications as compared to heparin. However, nonaccess site bleeding, that represent the majority of hemorrhagic complications, still carry negative prognostic consequences for these patients and no study has so far defined the exact impact of bivalirudin on nonaccess site bleeding, that was therefore the aim of present meta-analysis.

METHODS AND STUDY OUTCOMES

Literature archives (Pubmed, EMBASE, Cochrane) and main scientific sessions were scanned comparing bivalirudin vs. heparin in patients undergoing PCI. Primary endpoint was the occurrence of nonaccess site bleeding within 30 days. Secondary endpoints were 30 days mortality and the occurrence of access-site bleeding.

RESULTS

A total of nine randomized clinical trials were finally included, involving 32,587 patients, 55.8% randomized to bivalirudin. Bivalirudin significantly reduced the rate of nonaccess site bleeding (2.6 vs. 3.8%, OR [95% CI] = 0.68 [0.60-0.77], P < 0.00001, P_het  = 0.10). However, the reduction of hemorrhagic events was more pronounced when bivalirudin was compared to heparin plus glycoprotein IIbIIIa inhibitors than when it was compared to heparin alone (r = -0.01 (-0.02; -0.001), P = 0.02). Similar results were observed for access-site bleeding (OR [95% CI] = 0.67 [0.57-0.79], P < 0.000001, P_het  = 0.10), with a significant role of glycoprotein IIbIIIa inhibitors use (r = -0.02 (-0.04; -0.004), P = 0.017). Moreover, the observed benefits in hemorrhagic complications did not translate into mortality benefits (OR [95% CI] = 0.89 [0.76-1.05], P = 0.18; P_het  = 0.12; r = 0.21 (-1.12; 1.53), P = 0.76).

CONCLUSIONS

The present meta-analysis shows that bivalirudin can provide a significant reduction of both access and nonaccess site bleeding in patients undergoing PCI. However, these hemorrhagic benefits did not impact on survival, and moreover, were significantly conditioned by the association of heparin with potent antithrombotic strategies, such as glycoprotein IIbIIIa inhibitors, rather than by heparin or bivalirudin alone. Therefore, we could not provide any clinical evidence for the routine use of bivalirudin as preferred anticoagulation strategy for PCI. © 2017 Wiley Periodicals, Inc.

Short versus prolonged dual antiplatelet therapy (DAPT) duration after coronary stent implantation: A comparison between the DAPT study and 9 other trials evaluating DAPT duration

Aims

The Dual Antiplatelet Therapy (DAPT) study demonstrated that DAPT beyond 1-year after drug-eluting stent (DES) implantation, as compared with aspirin therapy alone, significantly reduced the risk of major cardiovascular and cerebrovascular events, which was mainly driven by the large risk reduction for myocardial infarction (MI). We sought to compare the largest DAPT study with other trials evaluating DAPT durations after DES implantation.

Methods and results

By a systematic literature search, we identified 9 trials comparing prolonged- versus short-DAPT in addition to the DAPT study. The result from the DAPT study (N = 9961) with public–private collaboration was different from the pooled result of the 9 other investigator-driven trials (N = 22174) in terms of the effect of prolonged-DAPT on MI (odds ratio [OR] 0.48 [95%CI 0.38–0.62] versus pooled OR 0.88 [95%CI 0.67–1.15]: P = 0.001 for difference), while the trends for excess risk of prolonged-DAPT relative to short-DAPT for all-cause death (OR 1.31 [95%CI 0.97–1.78] versus pooled OR 1.16 [95%CI 0.92–1.45]: P = 0.53 for difference), and bleeding (OR 1.62 [95%CI 1.21–2.17] versus pooled OR 2.08 [95%CI 1.51–2.84]: P = 0.25 for difference) were consistently seen in both the DAPT and other trials. The annual rate of MI during aspirin mono-therapy in the DAPT study was much higher than that those in the other trials (2.7% versus 0.6–1.6%).

Conclusions

Given the difference between the DAPT study and other trials, future studies should focus on certain subgroups of patients that are more or less likely to benefit from longer duration DAPT.

The optimal discontinuation of dual antiplatelet therapy in patients undergoing percutaneous coronary intervention with drug-eluting stents: A meta-analysis of randomized trials

BACKGROUND

Current guidelines recommend prolonged dual antiplatelet therapy (DAPT) for patients with drug-eluting stents (DES) implantation. Nevertheless, optimal discontinuation of DAPT remains a controversy. We performed a meta-analysis of all randomized controlled trials (RCTs) that evaluate optimal discontinuation of DAPT in patients undergoing percutaneous coronary intervention (PCI) with DES.

METHODS

We searched electronic databases including PubMed, Cochrane Library, EMBASE and ClinicalTrials.gov from database RCTs that reported different modes of discontinuation of DAPT in patients with DES. The primary endpoints were all-cause death, cardiovascular death, myocardial infarction (MI) and probably or definite stent thrombosis (ST). Secondary endpoints were repeat revascularization, stroke, major bleeding and net adverse clinical events (NACE).

RESULTS

We included 13 RCTs meeting the criteria with a total of 36,749 patients. No significant difference was observed in all-cause death (RR [95% CI]=0.87 [0.75, 1.01], P=0.07, I²=0%), cardiovascular death (RR [95% CI]=0.97 [0.79, 1.19], P=0.76, I²=0%), repeat revascularization (RR [95% CI]=1.07 [0.92, 1.25], P=0.36, I²=0%), and stroke (RR [95% CI]=1.01 [0.80, 1.28], P=0.94, I²=0%). Compared with shorter DAPT, longer DAPT was associated with a significant reduction in MI (RR [95% CI]=1.46 [1.26, 1.69], P<0.00001, I²=28%) and ST (RR [95% CI]=1.93 [1.45, 2.58], P<0.00001, I²=32%), and a significant increase in major bleeding (RR [95% CI]=0.60 [0.49, 0.74], P<0.00001, I²=0%). However, there was no difference in NACE (RR [95% CI]=1.03 [0.91, 1.17], P=0.63, I²=0%). In subgroup analyses based on stent type, we demonstrated that longer DAPT was associated with a significant reduction in thrombotic events (MI and ST) after first-generation DES implantation (RR [95% CI]=2.58 [1.85, 3.58], I²=0%) and everolimus-eluting stents (EES, RR [95% CI]=1.54 [1.12, 2.11], I²=0%). Conversely, there was no difference in thrombotic events in patients with zotarolimus-eluting stents (ZES, RR [95% CI]=1.17 [0.83, 1.63], I²=75%) and biodegradable polymer DES (BP-DES, RR [95% CI]=1.15 [0.74, 1.79]).

CONCLUSIONS

1) Compared with shorter DAPT, longer DAPT was associated with a significant reduction in thrombotic events (MI and ST) and a higher rate of major bleeding. 2) By the assessment of the trade-off between thrombotic and hemorrhagic events, shorter DAPT was non-inferior to longer DAPT. 3) The benefit of longer DAPT was significant in patients with first-generation DES and EES and weakened with other second-generation DES (ZES and BP-DES).

Organ transplantation and drug eluting stents: Perioperative challenges

Patients listed for organ transplant frequently have severe coronary artery disease (CAD), which may be treated with drug eluting stents (DES). Everolimus and zotarolimus eluting stents are commonly used. Newer generation biolimus and novolimus eluting biodegradable stents are becoming increasingly popular. Patients undergoing transplant surgery soon after the placement of DES are at increased risk of stent thrombosis (ST) in the perioperative period. Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor such as clopidogrel, prasugrel and ticagrelor is instated post stenting to decrease the incident of ST. Cangrelor has recently been approved by Food and Drug Administration and can be used as a bridging antiplatelet drug. The risk of ischemia vs bleeding must be considered when discontinuing or continuing DAPT for surgery. Though living donor transplant surgery is an elective procedure and can be optimally timed, cadaveric organ availability is unpredictable, therefore, discontinuation of antiplatelet medication cannot be optimally timed. The type of stent and timing of transplant surgery can be of utmost importance. Many platelet function point of care tests such as Light Transmittance Aggregrometry, Thromboelastography Platelet Mapping, VerifyNow, Multiple Electrode Aggregrometry are used to assess bleeding risk and guide perioperative platelet transfusion. Response to allogenic platelet transfusion to control severe intraoperative bleeding may differ with the antiplatelet drug. In stent thrombosis is an emergency where management with either a drug eluting balloon or a DES has shown superior outcomes. Post-transplant complications often involved stenosis of an important vessel that may need revascularization. DES are now used for endovascular interventions for transplant orthotropic heart CAD, hepatic artery stenosis post liver transplantation, transplant renal artery stenosis following kidney transplantation, etc. Several antiproliferative drugs used in the DES are inhibitors of mammalian target of rapamycin. Thus they are used for post-transplant immunosuppression to prevent acute rejection in recipients with heart, liver, lung and kidney transplantation. This article describes in detail the various perioperative challenges encountered in organ transplantation surgery and patients with drug eluting stents.

Randomized evaluation of short-term dual antiplatelet therapy in patients with acute coronary syndrome treated with the COMBO dual therapy stent: rationale and design of the REDUCE trial

BACKGROUND

The optimal duration of dual antiplatelet therapy (DAPT) in acute coronary syndrome (ACS) patients treated with drug eluting stents (DES) is still under debate. Recent meta-analyses on ≤6months versus 12months DAPT suggest that bleeding rates can be reduced, without a higher rate of thrombotic complications. In particular, the COMBO dual therapy stent, being associated with early re-endothelialization, may allow for a reduction of the duration of DAPT without increasing the thrombotic risk, while reducing the risk of bleeding complications.

AIM

The aim of the REDUCE trial is to demonstrate the non-inferiority of a combined efficacy and safety endpoint of a short-term 3months DAPT strategy as compared to standard 12-month DAPT strategy in ACS patients treated with the COMBO stent.

DESIGN

A prospective, multicenter, randomized study designed to enroll 1500 patients with ACS treated with the COMBO stent. Patients will be randomized before discharge in a 1:1 fashion to either 3 or 12months of DAPT. A clinical follow-up is scheduled at 3, 6, 12, and 24months. The primary endpoint is the time to event as defined by the occurrence of one of the following: all cause mortality, myocardial infarction, stent thrombosis, stroke, target vessel revascularization or bleeding (Bleeding Academic Research Council type II, III and V) within 12months. The study has recruited patients since July 2014, and the results are expected in 2017.

SUMMARY

A reduction of the DAPT duration in ACS patients after PCI without affecting the thrombotic risk is an attractive option with regard to the associated bleeding risk. The REDUCE trial will be the first to investigate the efficacy and safety of a 3-month DAPT strategy compared to a 12-month DAPT strategy in an ACS only population treated with the COMBO stent.