Duration of Dual Antiplatelet Therapy and Long-Term Clinical Outcome After Coronary Drug-Eluting Stent Implantation

Drug-coated balloon strategy following orbital atherectomy for calcified coronary artery compared with drug-eluting stent: One-year outcomes and optical coherence tomography assessment

BACKGROUND

Percutaneous coronary intervention (PCI) for calcified coronary artery remains challenging in the drug-eluting stent (DES) era. While recent studies reported the efficacy of orbital atherectomy (OA) combined with DES for calcified lesion, the effectiveness of drug-coated balloon (DCB) following OA has not been fully elucidated.

METHODS

Between June 2018 and June 2021, 135 patients who received PCI for calcified de novo coronary lesions with OA were enrolled and divided into two groups; OA followed by DCB (n = 43) if the target lesion achieved acceptable preparation, or second- or third-generation DESs (n = 92) if the target lesion showed suboptimal preparation between June 2018 and June 2021. All patients underwent PCI with optical coherence tomography (OCT) imaging. The primary endpoint was 1-year major adverse cardiac event (MACE), that was a composite of cardiac death, nonfatal myocardial infarction, or target lesion revascularization.

RESULTS

Mean age was 73 years and 82% was male. In OCT analysis, maximum calcium plaque was thicker (median: 1050 µm [interquartile range (IQR): 945-1175 µm] vs. 960 µm [808-1100 µm], p = 0.017), calcification arc tended to larger (median: 265° [IQR: 209-360°] vs. 222° [162-305°], p = 0.058) in patients with DCB than in DES, and the postprocedure minimum lumen area was smaller in DCB compared with minimum stent area in DES (median: 3.83 mm² [IQR: 3.30-4.52 mm² ] vs. 4.86 mm² [4.05-5.82 mm² ], p < 0.001). However, 1 year MACE free rate was not significantly different between 2 groups (90.3% in DCB vs. 96.6% in DES, log-rank p = 0.136). In the subgroup analysis of 14 patients who underwent follow-up OCT imaging, late lumen area loss was lower in patients with DCB than DES, despite lower lesion expansion rate in DCB than DES.

CONCLUSIONS

In calcified coronary artery disease, DCB alone strategy (if acceptable lesion preparation was performed with OA) was feasible compared with DES following OA with respect to 1-year clinical outcomes. Our finding indicated using DCB with OA might be reduce late lumen area loss for severe calcified lesion.

Bleeding risk in patients prescribed dual antiplatelet therapy and triple therapy after coronary interventions: the ADAPTT retrospective population-based cohort studies

Background

Bleeding among populations undergoing percutaneous coronary intervention or coronary artery bypass grafting and among conservatively managed patients with acute coronary syndrome exposed to different dual antiplatelet therapy and triple therapy (i.e. dual antiplatelet therapy plus an anticoagulant) has not been previously quantified.

Objectives

The objectives were to estimate hazard ratios for bleeding for different antiplatelet and triple therapy regimens, estimate resources and the associated costs of treating bleeding events, and to extend existing economic models of the cost-effectiveness of dual antiplatelet therapy.

Design

The study was designed as three retrospective population-based cohort studies emulating target randomised controlled trials.

Setting

The study was set in primary and secondary care in England from 2010 to 2017.

Participants

Participants were patients aged ≥ 18 years undergoing coronary artery bypass grafting or emergency percutaneous coronary intervention (for acute coronary syndrome), or conservatively managed patients with acute coronary syndrome.

Data sources

Data were sourced from linked Clinical Practice Research Datalink and Hospital Episode Statistics.

Interventions

Coronary artery bypass grafting and conservatively managed acute coronary syndrome: aspirin (reference) compared with aspirin and clopidogrel. Percutaneous coronary intervention: aspirin and clopidogrel (reference) compared with aspirin and prasugrel (ST elevation myocardial infarction only) or aspirin and ticagrelor.

Main outcome measures

Primary outcome: any bleeding events up to 12 months after the index event. Secondary outcomes: major or minor bleeding, all-cause and cardiovascular mortality, mortality from bleeding, myocardial infarction, stroke, additional coronary intervention and major adverse cardiovascular events.

Results

The incidence of any bleeding was 5% among coronary artery bypass graft patients, 10% among conservatively managed acute coronary syndrome patients and 9% among emergency percutaneous coronary intervention patients, compared with 18% among patients prescribed triple therapy. Among coronary artery bypass grafting and conservatively managed acute coronary syndrome patients, dual antiplatelet therapy, compared with aspirin, increased the hazards of any bleeding (coronary artery bypass grafting: hazard ratio 1.43, 95% confidence interval 1.21 to 1.69; conservatively-managed acute coronary syndrome: hazard ratio 1.72, 95% confidence interval 1.15 to 2.57) and major adverse cardiovascular events (coronary artery bypass grafting: hazard ratio 2.06, 95% confidence interval 1.23 to 3.46; conservatively-managed acute coronary syndrome: hazard ratio 1.57, 95% confidence interval 1.38 to 1.78). Among emergency percutaneous coronary intervention patients, dual antiplatelet therapy with ticagrelor, compared with dual antiplatelet therapy with clopidogrel, increased the hazard of any bleeding (hazard ratio 1.47, 95% confidence interval 1.19 to 1.82), but did not reduce the incidence of major adverse cardiovascular events (hazard ratio 1.06, 95% confidence interval 0.89 to 1.27). Among ST elevation myocardial infarction percutaneous coronary intervention patients, dual antiplatelet therapy with prasugrel, compared with dual antiplatelet therapy with clopidogrel, increased the hazard of any bleeding (hazard ratio 1.48, 95% confidence interval 1.02 to 2.12), but did not reduce the incidence of major adverse cardiovascular events (hazard ratio 1.10, 95% confidence interval 0.80 to 1.51). Health-care costs in the first year did not differ between dual antiplatelet therapy with clopidogrel and aspirin monotherapy among either coronary artery bypass grafting patients (mean difference £94, 95% confidence interval -£155 to £763) or conservatively managed acute coronary syndrome patients (mean difference £610, 95% confidence interval -£626 to £1516), but among emergency percutaneous coronary intervention patients were higher for those receiving dual antiplatelet therapy with ticagrelor than for those receiving dual antiplatelet therapy with clopidogrel, although for only patients on concurrent proton pump inhibitors (mean difference £1145, 95% confidence interval £269 to £2195).

Conclusions

This study suggests that more potent dual antiplatelet therapy may increase the risk of bleeding without reducing the incidence of major adverse cardiovascular events. These results should be carefully considered by clinicians and decision-makers alongside randomised controlled trial evidence when making recommendations about dual antiplatelet therapy.

Limitations

The estimates for bleeding and major adverse cardiovascular events may be biased from unmeasured confounding and the exclusion of an eligible subgroup of patients who could not be assigned an intervention. Because of these limitations, a formal cost-effectiveness analysis could not be conducted.

Future work

Future work should explore the feasibility of using other UK data sets of routinely collected data, less susceptible to bias, to estimate the benefit and harm of antiplatelet interventions.

Trial registration

This trial is registered as ISRCTN76607611.

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 27, No. 8. See the NIHR Journals Library website for further project information.

Relationship Between Platelet Reactivity and Ischemic and Bleeding Events After Percutaneous Coronary Intervention in East Asian Patients: 1-Year Results of the PENDULUM Registry

Background The balance between ischemic and bleeding events and their association with platelet reactivity in patients receiving antiplatelet therapy after percutaneous coronary intervention (PCI), which differs among regions, is not fully evaluated for East Asians. We examined ischemic/bleeding events and platelet reactivity in Japanese patients undergoing PCI and determined associations between high/low platelet reactivity and clinical outcomes. Methods and Results PENDULUM (Platelet Reactivity in Patients with Drug Eluting Stent and Balancing Risk of Bleeding and Ischemic Event) is a prospective, multicenter registry of Japanese patients with PCI. Primary end points were incidence of first major adverse cardiac and cerebrovascular events (MACCE) and first major bleeding events at 12 months post-PCI. Platelet reactivity (P2Y₁₂ reaction unit [PRU] value) was measured at 12 to 48 hours post-PCI; patients were grouped as having high PRU (>208), optimal PRU (>85 to ≤208), and low PRU (≤85). MACCE and major bleeding occurred in 4.4% and 2.8% of 6267 patients, respectively. The mean±SD PRU value was 182.1±77.1. MACCE was significantly higher in the high PRU (5.7%; n=2227) versus the optimal PRU group (3.6%; n=3002). The hazard ratio (HR) for high PRU versus optimal PRU level was significantly higher for MACCE (adjusted HR, 1.53; 95% CI, 1.14-2.06 [P=0.004]); stent thrombosis followed the same trend. Incidence of major bleeding did not differ significantly between groups. A high PRU level was significantly associated with MACCE in both patients with and patients without acute coronary syndrome. Conclusions These real-world data suggest an association between high platelet reactivity and cardiovascular events in Japanese patients undergoing PCI. The trend was the same in both patients with and patients without acute coronary syndrome. REGISTRATION URL: https://www.umin.ac.jp/ctr. Unique identifier: UMIN 000020332.

Comprehensive ascertainment of bleeding in patients prescribed different combinations of dual antiplatelet therapy (DAPT) and triple therapy (TT) in the UK: study protocol for three population-based cohort studies emulating 'target trials' (the ADAPTT Study)

INTRODUCTION

'Real world' bleeding in patients exposed to different regimens of dual antiplatelet therapy (DAPT) and triple therapy (TT, DAPT plus an anticoagulant) have a clinical and economic impact but have not been previously quantified.

METHODS AND ANALYSIS

We will use linked Clinical Practice Research Datalink (CPRD) and Hospital Episode Statistics (HES) data to assemble populations eligible for three 'target trials' in patient groups: percutaneous coronary intervention (PCI); coronary artery bypass grafting (CABG); conservatively managed (medication only) acute coronary syndrome (ACS). Patients ≥18 years old will be eligible if, in CPRD records, they have: ≥1 year of data before the index event; no prescription for DAPT or anticoagulants in the preceding 3 months; a prescription for aspirin or DAPT within 2 months after discharge from the index event. The primary outcome will be any bleeding event (CPRD or HES) up to 12 months after the index event. We will estimate adjusted HR for time to first bleeding event comparing: aspirin and clopidogrel (reference) versus aspirin and prasugrel or aspirin and ticagrelor after PCI; and aspirin (reference) versus aspirin and clopidogrel after CABG and ACS. We will describe rates of bleeding in patients prescribed TT (DAPT plus an anticoagulant). Potential confounders will be identified systematically using literature review, semistructured interviews with clinicians and a short survey of clinicians. We will conduct sensitivity analyses addressing the robustness of results to the study's main limitation-that we will not be able to identify the intervention group for patients whose bleeding event occurs before a DAPT prescription in CPRD.

ETHICS AND DISSEMINATION

This protocol was approved by the Independent Scientific Advisory Committee for the UK Medicines and Healthcare Products Regulatory Agency Database Research (protocol 16_126R) and the South West Cornwall and Plymouth Research Ethics Committee (17/SW/0092). The findings will be presented in peer-reviewed journals, lay summaries and briefing papers to commissioners/other stakeholders.

TRIAL REGISTRATION NUMBER

76607611; Pre-results.

Validating Utility of Dual Antiplatelet Therapy Score in a Large Pooled Cohort From 3 Japanese Percutaneous Coronary Intervention Studies

Background:

The dual antiplatelet therapy (DAPT) score was developed to estimate ischemic and bleeding risks from the DAPT study. However, few studies validated its utility externally. We sought to validate the utility of the DAPT score in the Japanese population.

Methods:

In a pooled cohort of 3 studies conducted in Japan (the CREDO-Kyoto [Coronary Revascularization Demonstrating Outcome Study in Kyoto] Registry Cohort-2, RESET [Randomized Evaluation of Sirolimus-Eluting Versus Everolimus-Eluting Stent Trial], and NEXT [NOBORI Biolimus-Eluting Versus XIENCE/PROMUS Everolimus-Eluting Stent Trial]), we compared risks for ischemic and bleeding events from 13 to 36 months after percutaneous coronary intervention among patients with a DAPT score ≥2 (high DS) and a DAPT score <2 (low DS).

Results:

Among 12 223 patients receiving drug-eluting stents who were free from ischemic or bleeding events at 13 months after percutaneous coronary intervention, 3944 patients had high DS and 8279 had low DS. The cumulative incidence of primary ischemic end point (myocardial infarction/stent thrombosis) was significantly higher in high DS than in low DS (1.5% versus 0.9%, P =0.002), whereas the cumulative incidence of primary bleeding end point (GUSTO moderate/severe) tended to be lower in high DS than in low DS (2.1% versus 2.7%, P =0.07). The cumulative incidences of cardiac death, myocardial infarction, and stent thrombosis were also significantly higher in high DS than in low DS (2.0% versus 1.4%, P =0.03; 1.5% versus 0.8%, P =0.002; 0.7% versus 0.3%, P <0.001, respectively), whereas the cumulative incidences of noncardiac death and GUSTO severe bleeding were significantly lower in high DS than in low DS (2.4% versus 3.9%, P <0.001; 1.0% versus 1.6%, P =0.03, respectively).

Conclusions:

In the current population, the DAPT score successfully stratified ischemic and bleeding risks, although the ischemic event rate was remarkably low even in high DS. Further studies would be warranted to evaluate the utility of prolonged DAPT guided by the DAPT score.

Impact of Transient or Persistent Contrast-induced Nephropathy on Long-term Mortality After Elective Percutaneous Coronary Intervention

Contrast-induced nephropathy (CIN) is associated with increased long-term mortality. However, it is still controversial whether CIN is the cause of increased mortality or merely a marker of high-risk patients. The current study population included 5,516 patients who underwent their first elective percutaneous coronary intervention (PCI) in the Coronary REvascularization Demonstrating Outcome Study in Kyoto registry cohort-2. CIN was defined as an elevation in the peak serum creatinine (SCr) of ≥0.5 mg/dl from the baseline within 5 days after PCI. CIN, seen in 218 patients (4.0%), was independently associated with an increased long-term mortality risk (hazard ratio [HR] 1.43, 95% confidence interval [CI],1.11 to 1.83; p = 0.005). SCr data at 1 year (180 to 550 days) after PCI were available in 3,986 patients, who were subdivided into persistent CIN (follow-up SCr elevation ≥0.5 mg/dl: n = 50 [1.3%]), transient CIN (follow-up SCr elevation <0.5 mg/dl: n = 90 [2.3%]), and non-CIN (n = 3,846 [96.5%]). In the landmark analysis at 1 year after PCI, 524 patients (13.1%) died during a median follow-up of 1,521 days. After adjustment for the 37 confounders, persistent CIN, but not transient CIN, was significantly correlated with a higher long-term mortality risk compared with non-CIN (HR 1.84, 95% CI 1.12 to 3.03; p = 0.02, and HR 1.11, 95% CI 0.71 to 1.76; p = 0.6, respectively). In conclusion, only persistent CIN was independently associated with increased long-term mortality.

Clinical Outcomes and Bioprosthetic Valve Function After Transcatheter Aortic Valve Implantation Under Dual Antiplatelet Therapy vs. Aspirin Alone

BACKGROUND

Dual antiplatelet therapy (DAPT) is commonly used after transcatheter aortic valve implantation (TAVI); however, the supporting evidence is limited. To determine if aspirin alone is a better alternative to DAPT, we compared the outcomes of patients treated with DAPT or aspirin alone after TAVI.Methods and Results:We analyzed a total of 144 consecutive patients (92 females, mean age 83±6 years) who underwent implantation of a balloon-expandable transcatheter valve (SAPIEN or SAPIEN XT, Edwards Lifesciences). Patients were divided into DAPT (n=66) or aspirin-alone treatment groups (n=78). At 1 year after TAVI, the composite endpoint, which consisted of all-cause death, myocardial infarction, stroke, and major or life-threatening bleeding complications, occurred significantly less frequently (Kaplan-Meier analysis) in the aspirin-alone group (15.4%) than in the DAPT group (30.3%; P=0.031). Valve function assessed by echocardiography was similar between the 2 treatment groups with respect to effective orifice area (1.78±0.43 cm²in DAPT vs. 1.91±0.46 cm²in aspirin-alone group; P=0.13) and transvalvular pressure gradient (11.1±3.5 mmHg in DAPT vs. 10.3±4.1 mmHg in aspirin-alone group; P=0.31).

CONCLUSIONS

Treatment with aspirin alone after TAVI had greater safety benefits and was associated with similar valve function as DAPT. These results suggest that treatment with aspirin alone is an acceptable regimen for TAVI patients.

Optimal Duration of Dual Antiplatelet Therapy after Drug-Eluting Stents: Meta-Analysis of Randomized Trials

INTRODUCTION

The optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent implantation (DES) is not certain. The AHA/ACC guidelines recommend 12 months of DAPT based on observational trials. Recently, several large randomized controlled trials (RCT) suggested a noninferiority of shorter duration of DAPT and other trials showed a benefit from extended duration of DAPT after 12 months of DES implantation.

METHODS

PubMed databases were searched for RCTs comparing the continued use of DAPT to shorter duration of DAPT (aspirin alone) for variable durations beyond 3 months of DES implantation. Our analysis was limited to trials with clinical outcomes. Odds ratio (OR) and 95% confidence intervals (CI) were calculated using fixed and random-effects models. Subgroup analyses were performed for second generation DES and for trials comparing 12 months of DAPT vs. earlier interruption or longer duration of DAPT.

RESULTS

We identified 10 RCTs including 32,136 subjects randomized to continued use of DAPT vs. aspirin alone for variable durations after 3 months of DES implantation. There was no significant heterogeneity among studies (Q test P > 0.1). Compared to shorter DAPT, longer DAPT resulted in a significant reduction in stent thrombosis (0.3% vs. 0.7%, P < 0.01) and myocardial infarction (1.3% vs. 2%, P < 0.01), and a significant increase in major bleeding (0.8% vs. 0.4%, P < 0.01). There was no difference in cardiac deaths or stroke. All-cause deaths were slightly lower with shorter DAPT compared to longer DAPT (OR 0.8, 95% CI 0.7 to 0.99, P = 0.04). A small number of subjects were included between 3 and 6 months after DES implantation.

CONCLUSION

DAPT continued beyond 6 months after second generation DES implantation decreases stent thrombosis and myocardial infarction, but increases major bleeding and all-causes mortality compared to shorter DAPT (aspirin alone). There was no difference in cardiac mortality or stroke.

Prolonged Clopidogrel Use is Associated with Improved Clinical Outcomes Following Drug-Eluting But Not Bare Metal Stent Implantation

BACKGROUND

Guidelines recommend clopidogrel use for 6-12 months following drug-eluting stent (DES) implantation and 1-12 months following bare metal stent (BMS) implantation. The role of clopidogrel beyond 12 months is unclear.

METHODS

We linked hospital administrative, community pharmacy and cardiac revascularization data to determine clopidogrel use and outcomes for all patients (those with acute presentations and those with stable angina) receiving a coronary stent in British Columbia 2004-2006, with follow-up until the end of 2008. Cox proportional hazard regression was performed to evaluate the effect of clopidogrel duration (≤12 vs. >12 months) on outcomes following BMS or DES implantation. Patients who died ≤12 months from index stent placement were excluded.

RESULTS

A total of 15,629 patients were included in the study. Of 3599 patients who received at least one DES and 12,030 patients who received only BMS, 1326 (37 %) and 2121 (18 %), respectively, filled a prescription for clopidogrel >12 months from the index procedure. The mean duration of clopidogrel was 406 ± 35 days and 407 ± 37 days in the prolonged use (>12 months) DES and BMS cohorts, respectively, compared with 224 ± 112 days (p < 0.001) and 122 ± 117 days (p < 0.001), respectively, for patients receiving clopidogrel ≤12 months. Clopidogrel use beyond 12 months was associated with a reduction in mortality [hazard ratio (HR) 0.66, 95 % confidence interval (CI) 0.45-0.97] and the composite of mortality and readmission for myocardial infarction (HR 0.72, 95 % CI 0.55-0.94) in patients treated with DES, but not BMS alone. Prolonged clopidogrel use was not associated with bleeding-related mortality.

CONCLUSIONS

Clopidogrel use beyond 12 months was associated with a reduction in death and hospitalization for myocardial infarction following DES, but not BMS, implantation. Our findings support a longer duration of clopidogrel therapy for patients treated with DES.

Safety of an abbreviated duration of dual antiplatelet therapy (≤6 months) following second-generation drug-eluting stents for coronary artery disease: A systematic review and meta-analysis of randomized trials

BACKGROUND

Dual antiplatelet therapy (DAPT) is recommended for ≥12 months following coronary drug-eluting stents (DES) to reduce risk of major adverse ischemic events. Randomized trials suggest an abbreviated DAPT duration (≤6 months) is adequately protective. However, these trials are individually underpowered to detect differences in rare but serious events such as stent thrombosis (ST).

OBJECTIVES

We performed a meta-analysis of published randomized trials to define the impact of abbreviated DAPT (≤6 months) on death, myocardial infarction (MI), stent thrombosis (ST), and bleeding complications compared to standard-duration DAPT (≥12 months).

METHODS

Seven randomized controlled trials comparing abbreviated vs. standard DAPT regimens following DES use were identified by two independent investigators. Study characteristics were reviewed and clinical endpoint data were abstracted and analyzed in aggregate using fixed and random-effects models.

RESULTS

The seven trials included 15,874 randomized patients. Second-generation DES were used in most patients. Compared to standard-duration DAPT, abbreviated DAPT was not associated with an increase in mortality (OR 0.93; CI: 0.73 to 1.17; P = 0.52), MI (OR 1.14; CI: 0.89 to 1.45; P = 0.30) or ST (OR 1.25; CI: 0.81 to 1.93; P = 0.31). Abbreviated DAPT was associated with significantly fewer major bleeding complications (OR 0.52; CI: 0.34 to 0.82; P = 0.005). The results were consistent between fixed and random-effects models, with no heterogeneity. Sensitivity analyses adjusting for inclusion of bare metal stents, 1st generation DES and/or abbreviated DAPT regimens of 3 months resulted in similar conclusions.

CONCLUSIONS

In a meta-analysis of >15,000 patients primarily treated with second-generation DES, abbreviated-duration DAPT (≤6 months) was associated with a significant reduction in major bleeding complications with no evidence of a significant increase in risk of death, MI or ST. Accordingly, abbreviated DAPT should be strongly considered for patients receiving second generation DES.

Long-Term Outcomes After Coronary Stent Implantation in Patients Presenting With Versus Without Acute Myocardial Infarction (an Observation from Coronary Revascularization Demonstrating Outcome Study-Kyoto Registry Cohort-2)

It has not been adequately addressed yet how long the excess cardiovascular event risk persists after acute myocardial infarction (AMI) compared with stable coronary artery disease. Of 10,470 consecutive patients who underwent percutaneous coronary intervention either with sirolimus-eluting stent (SES) only or with bare-metal stent (BMS) only in the Coronary Revascularization Demonstrating Outcome Study-Kyoto Registry Cohort-2, 3,710 (SES: n = 820 and BMS: n = 2,890) and 6,760 patients (SES: n = 4,258 and BMS: n = 2,502) presented with AMI (AMI group) and without AMI (non-AMI group), respectively. During the median 5-year follow-up, the excess adjusted risk of the AMI group relative to the non-AMI group for the primary outcome measure (cardiac death or myocardial infarction) was significant (hazard ratio [HR] 1.53, 95% confidence interval [CI] 1.30 to 1.80, p <0.001). However, the excess event risk was limited to the early period within 3 months. Late adjusted risk beyond 3 months was similar between the AMI and non-AMI groups (HR 1.16, 95% CI 0.95 to 1.41, p = 0.15). The higher risk of the AMI group relative to the non-AMI group for stent thrombosis (ST) was significant within 3 months (HR 3.38, 95% CI 2.04 to 5.60, p <0.001), whereas the risk for ST was not different between the 2 groups beyond 3 months (HR 1.11, 95% CI 0.65 to 1.90, p = 0.70). There were no interactions between the types of stents implanted and the risk of the AMI group relative to the non-AMI groups for all the outcome measures including ST. In conclusion, patients with AMI compared with those without AMI were associated with similar late cardiovascular event risk beyond 3 months after percutaneous coronary intervention despite their higher early risk within 3 months.

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

Despite new-generations of drug-eluting stents (DESs), the optimal duration of dual antiplatelet therapy (DAPT) remains controversial. We performed a meta-analysis of randomized trials (RTs) evaluating the effectiveness and safety of shorter versus longer DAPT duration strategies in patients undergoing percutaneous coronary interventions with DES. Literature and main scientific session abstracts were searched. The primary end point was mortality. Secondary end points were (1) cardiovascular mortality, (2) nonfatal myocardial infarction, (3) definite/probable stent thrombosis (ST), and (4) major bleedings. We included 11 RTs (n = 32 372 patients). Shorter DAPT duration reduced mortality (odds ratio, OR [95% confidence interval, CI] = 0.85 [0.71-1], P = .05; p heterogeneity = 0.91). Similar results were observed when comparing 3 to 6 versus 12 months DAPT, while a significant increase in recurrent ischemic events was found for 6 to 12 months DAPT versus extended treatment (myocardial infarction: OR [95%CI] = 1.66 [1.37-2], P < .00001; phet = 0.13 and ST: OR [95%CI] = 2.47 [1.72-3.45], P < .00001; phet = 0.12), however, counterbalanced by a significant reduction in major bleeding (OR [95%CI] = 0.60 [0.47-0.76], P < .0001; phet = 0.38) and a trend in lower mortality. Thus, among selected patients undergoing DES implantation, a shorter DAPT strategy is associated with reduction in mortality and major bleeding but a higher risk of myocardial infarction and ST. A short duration (3-6 months) of DAPT appears as the safest strategy, while a prolonged duration (24-36 months) reduces thrombotic complications but with an excess in major bleeding complications.

Antiplatelet therapy discontinuation and the risk of serious cardiovascular events after coronary stenting: observations from the CREDO-Kyoto Registry Cohort-2

Relation of antiplatelet therapy (APT) discontinuation with the risk of serious cardiovascular events has not been fully addressed yet. This study is aimed to evaluate the risk of ischemic event after APT discontinuation based on long-term APT status of large cohort. In the CREDO-Kyoto Registry Cohort-2 enrolling 15939 consecutive patients undergoing first coronary revascularization, 10470 patients underwent percutaneous coronary intervention either with bare-metal stents (BMS) only (N=5392) or sirolimus-eluting stents (SES) only (N=5078). Proportions of patients taking dual-APT were 67.3% versus 33.4% at 1-year, and 48.7% versus 24.3% at 5-year in the SES and BMS strata, respectively. We evaluated daily APT status (dual-, single- and no-APT) and linked the adverse events to the APT status just 1-day before the events. No-APT as compared with dual- or single-APT was associated with significantly higher risk for stent thrombosis (ST) beyond 1-month after SES implantation (cumulative incidence rates beyond 1-month: 1.23 versus 0.15/0.29, P<0.001/P<0.001), while higher risk of no-APT for ST was evident only until 6-month after BMS implantation (incidence rates between 1- and 6-month: 8.43 versus 0.71/1.20, P<0.001/P<0.001, and cumulative incidence rates beyond 6-month: 0.31 versus 0.11/0.08, P=0.16/P=0.08). No-APT as compared with dual- or single-APT was also associated with significantly higher risk for spontaneous myocardial infarction (MI) and stroke regardless of the types of stents implanted. Single-APT as compared with dual-APT was not associated with higher risk for serious adverse events, except for the marginally higher risk for ST in the SES stratum. In conclusion, discontinuation of both aspirin and thienopyridines was associated with increased risk for serious cardiovascular events including ST, spontaneous MI and stroke beyond 1-month after coronary stenting.

Thienopyridine use after coronary stenting in low income patients enrolled in medicare part D receiving maintenance dialysis

BACKGROUND

Coronary stenting in patients on dialysis has increased by nearly 50% over the past decade, despite heightened risks of associated stent thrombosis and bleeding relative to the general population. We examined clopidogrel, prasugrel or ticlopidine use after percutaneous coronary intervention (PCI) with stenting in patients on dialysis. We conducted 3-, 6-, and 12-month landmark analyses to test the hypothesis that thienopyridine discontinuation prior to those time points would be associated with higher risks of death, myocardial infarction, or repeat revascularization, and a lower risk of major bleeding episodes compared with continued thienopyridine use.

METHODS AND RESULTS

Using the US Renal Data System, we identified 8458 patients on dialysis with Medicare Parts A+B+D undergoing PCI with stenting between July 2007 and December 2010. Ninety-nine percent of all thienopyridine prescriptions were for clopidogrel. At 3 months, 82% of patients who received drug-eluting stents (DES) had evidence of thienopyridine use. These proportions fell to 62% and 40% at 6 and 12 months, respectively. In patients who received a bare-metal stent (BMS), 70%, 34%, and 26% of patients had evidence of thienopyridine use at 3, 6, and 12 months, respectively. In patients who received a DES, there was a suggestion of higher risks of death or myocardial infarction associated with thienopyridine discontinuation in the 3-, 6-, and 12-months landmark analyses, but no higher risk of major bleeding episodes. In patients who received a BMS, there were no differences in death or cardiovascular events, and possibly lower risk of major bleeding with thienopyridine discontinuation in the 3- and 6-month landmark analyses.

CONCLUSIONS

The majority of patients on dialysis who undergo PCI discontinue thienopyridines before 1 year regardless of stent type. While not definitive, these data suggest that longer-term thienopyridine use may be of benefit to patients on dialysis who undergo PCI with DES.

Percutaneous coronary intervention versus coronary artery bypass grafting in patients with end-stage renal disease requiring dialysis (5-year outcomes of the CREDO-Kyoto PCI/CABG Registry Cohort-2)

Ischemic heart disease is a major risk factor for morbidity and mortality in patients with end-stage renal disease. However, long-term benefits of percutaneous coronary intervention (PCI) relative to coronary artery bypass grafting (CABG) in those patients is still unclear in the drug-eluting stent era. We identified 388 patients with multivessel and/or left main disease with end-stage renal disease requiring dialysis among 15,939 patients undergoing first coronary revascularization enrolled in the Coronary REvascularization Demonstrating Outcome Study in Kyoto PCI/CABG Registry Cohort-2 (PCI: 258 patients and CABG: 130 patients). The CABG group included more patients with 3-vessel (38% vs 57%, p <0.001) and left main disease (10% vs 34%, p <0.001). Preprocedural Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery score in the CABG group was significantly higher than that in the PCI group (23.5 ± 8.7 vs 29.4 ± 11.0, p <0.001). Unadjusted 30-day mortality was 2.7% for PCI and 5.4% for CABG. Cumulative 5-year all-cause mortality was 52.3% for PCI and 49.9% for CABG. Propensity score-adjusted all-cause mortality was not different between PCI and CABG (hazard ratio [HR] 1.33, 95% confidence interval [CI] 0.85 to 2.09, p = 0.219). However, the excess risk of PCI relative to CABG for cardiac death was significant (HR 2.10, 95% CI 1.11 to 3.96, p = 0.02). The risk of sudden death was also higher after PCI (HR 4.83, 95% CI 1.01 to 23.08, p = 0.049). The risk of myocardial infarction after PCI tended to be higher than after CABG (HR 3.30, 95% CI 0.72 to 15.09, p = 0.12). The risk of any coronary revascularization after PCI was markedly higher after CABG (HR 3.78, 95% CI 1.91 to 7.50, p <0.001). Among the 201 patients who died during the follow-up, 94 patients (47%) died from noncardiac morbidities such as stroke, respiratory failure, and renal failure. In patients with multivessel and/or left main disease undergoing dialysis, 5-year outcomes revealed that CABG relative to PCI reduced the risk of cardiac death, sudden death, myocardial infarction, and any revascularization. However, the risk of all-cause death was not different between PCI and CABG.

Clopidogrel discontinuation within the first year after coronary drug-eluting stent implantation: an observational study

BACKGROUND

The impact of adherence to the recommended duration of dual antiplatelet therapy after first generation drug-eluting stent implantation is difficult to assess in real-world settings and limited data are available.

METHODS

We followed 4,154 patients treated with coronary drug-eluting stents in Western Denmark for 1 year and obtained data on redeemed clopidogrel prescriptions and major adverse cardiovascular events (MACE, i.e., cardiac death, myocardial infarction, or stent thrombosis) from medical databases.

RESULTS

Discontinuation of clopidogrel within the first 3 months after stent implantation was associated with a significantly increased rate of MACE at 1-year follow-up (hazard ratio (HR) 2.06; 95% confidence interval (CI): 1.08-3.93). Discontinuation 3-6 months (HR 1.29; 95% CI: 0.70-2.41) and 6-12 months (HR 1.29; 95% CI: 0.54-3.07) after stent implantation were associated with smaller, not statistically significant, increases in MACE rates. Among patients who discontinued clopidogrel, MACE rates were highest within the first 2 months after discontinuation.

CONCLUSIONS

Discontinuation of clopidogrel was associated with an increased rate of MACE among patients treated with drug-eluting stents. The increase was statistically significant within the first 3 months after drug-eluting stent implantation but not after 3 to 12 months.

Anticoagulant and antiplatelet therapy in patients with atrial fibrillation undergoing percutaneous coronary intervention

The prevalence, intensity, safety, and efficacy of oral anticoagulation (OAC) in addition to dual antiplatelet therapy (DAPT) in "real-world" patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI) have not yet been fully evaluated. In the Coronary REvascularization Demonstrating Outcome Study in Kyoto registry cohort-2, a total of 1,057 patients with AF (8.3%) were identified among 12,716 patients undergoing first PCI. Cumulative 5-year incidence of stroke was higher in patients with AF than in no-AF patients (12.8% vs 5.8%, p <0.0001). Although most patients with AF had CHADS2 score ≥2 (75.2%), only 506 patients (47.9%) received OAC with warfarin at hospital discharge. Cumulative 5-year incidence of stroke in the OAC group was not different from that in the no-OAC group (13.8% vs 11.8%, p = 0.49). Time in therapeutic range (TTR) was only 52.6% with an international normalized ratio of 1.6 to 2.6, and only 154 of 409 patients (37.7%) with international normalized ratio data had TTR ≥65%. Cumulative 5-year incidence of stroke in patients with TTR ≥65% was markedly lower than that in patients with TTR <65% (6.9% vs 15.1%, p = 0.01). In a 4-month landmark analysis in the OAC group, there was a trend for higher cumulative incidences of stroke and major bleeding in the on-DAPT (n = 286) than in the off-DAPT (n = 173) groups (15.1% vs 6.7%, p = 0.052 and 14.7% vs 8.7%, p = 0.10, respectively). In conclusion, OAC was underused and its intensity was mostly suboptimal in real-world patients with AF undergoing PCI, which lead to inadequate stroke prevention. Long-term DAPT in patients receiving OAC did not reduce stroke incidence.

Adherence to dual antiplatelet therapy after coronary stenting: a systematic review

BACKGROUND

Adherence to dual antiplatelet therapy (DAPT) is critical after coronary stenting. Although adherence rates are frequently assessed in clinical trials, adherence rates in the unselected population recommended for treatment but beyond clinical trials are largely unknown. Therefore, we performed a systematic review of published observational studies to describe rates of DAPT adherence, trends in DAPT use over time, and patient-level factors associated with nonadherence.

HYPOTHESIS

DAPT adherence declines with increasing time after drug-eluting stent implantation.

METHODS

PubMed, Cumulative Index to Nursing and Allied Health Literature, Embase, and Web of Knowledge were searched through November 20, 2012 for studies including patients receiving 1 or more drug-eluting stents and reporting the use of aspirin and/or thienopyridines, or assessing factors associated with nonadherence to DAPT after bare metal or drug-eluting stent placement.

RESULTS

We included 34 studies in the description of DAPT adherence and 11 studies in the description of factors associated with nonadherence. Adherence to DAPT and thienopyridines was high at 1 month but declined by 12 months. Aspirin adherence was at least 90% throughout. Factors associated with nonadherence included bleeding, lower education level, immigrant status, and lack of education regarding DAPT.

CONCLUSIONS

DAPT adherence is suboptimal at 12 months, and interventions to increase adherence should focus on reducing bleeding risk and improving communication between patients and physicians.

Discontinuation of dual antiplatelet therapy over 12 months after acute coronary syndromes increases risk for adverse events in patients treated with percutaneous coronary intervention: systematic review and meta-analysis

INTRODUCTION

Duration of dual antiplatelet therapy (DAPT) following acute coronary syndrome (ACS) hospitalization remains to be defined, both for patients treated medically and for those undergoing percutaneous transluminal coronary angioplasty (PTCA).

METHODS

PubMed, Cochrane, and Google Scholar were systematically searched for studies including patients presenting with ACS, and treated either with DAPT longer than or shorter than 12 months. Multivariable-adjusted risk estimates for death and recurrent ACS with stopping DAPT after 12 months (odds ratios [OR] 95% confidence intervals [CI]) were pooled after logarithmic transformation according to random-effect models with inverse-variance weighting.

RESULTS

Five studies with 49,586 patients were included. Median age was 66 (64-67) years, with 67% (65-75) males. Myocardial infarction (MI) represented the admission diagnosis for 88% (60-100) of the patients, and 66% (50-74) were treated with stenting. After a follow-up of 2.1 years (1.5-2.7), 40% (35-46) still on DAPT after 12 months and the rates of death or recurrent ACS were 16.6 (14.5-17.0). Risk of adverse events for patients stopping DAPT after 1 year was significantly increased (OR = 1.19 [1.07-1.32]) for those receiving stents, but not for patients managed medically (OR = 1.13 [0.95-1.35]). The increased risk did not vary according to age, gender, myocardial infarction as admission diagnosis, and kind of stent.

CONCLUSIONS

Interruption of DAPT over 12 months after ACS increases the risk of adverse events for patients treated with PTCA, but not for those managed conservatively, independently from baseline features and admission diagnosis. This hypothesis-generating finding should be tested in randomized controlled trials.

How to manage prasugrel and ticagrelor in daily practice

Prasugrel and ticagrelor are next-generation antiplatelet agents that provide a rapider and more potent inhibition of platelet P2Y12 receptor than clopidogrel. In combination with aspirin, these new P2Y12 inhibitors are now the first line treatments for patients with acute coronary syndrome. However, these potent antiplatelet agents introduce a new paradigm in the daily management of antithrombotic drugs, particularly when an invasive procedure is planned. The pharmacology of these antiplatelet agents, and the results of the main clinical trials, are reviewed with a special focus on good prescription practices (indications, contra-indications, drug interactions), and on peri-operative management. Strategies are proposed for safely reducing the bleeding risk in elderly patients, in patients requiring concomitant oral anticoagulant therapy, or in patients with an increased haemorrhagic risk.

Risk of Intracranial Hemorrhage With Protease-Activated Receptor-1 Antagonists

Background and Purpose—

Recent clinical trial data suggest that protease-activated receptor-1 (PAR-1) antagonists may increase the risk of intracranial hemorrhage. Our objective was to investigate the qualitative and quantitative risks of intracranial hemorrhage in patients receiving PAR-1 antagonist therapy.

Methods—

Pubmed, EMBASE, Cochrane Central Register of Controlled Trials, and Clinicaltrials.gov from 1966 to May 2012, were searched to identify relevant studies. We included randomized controlled trials that included a comparison of PAR-1 antagonist with placebo and in which the total number of patients and intracranial hemorrhage events were reported separately for active treatment and control groups. Summary incidence rates, relative risks, and 95% confidence intervals (CIs) were calculated using random-effects models. Between-study heterogeneity was assessed using the I 2 statistic.

Results—

In 9 PAR-1 antagonist trials with 42000 patients with a history of thrombotic vascular disease or acute coronary syndrome, PAR-1 antagonist treatment was associated with increased risk of intracranial hemorrhage (0.59% vs 0.30%; relative risk, 1.98; 95% CI, 1.46–2.68; P <0.00001; number needed to harm, 345). There was no heterogeneity across trials ( P =0.84; I 2 =0%), PAR-1 antagonist agent ( P =0.52), treatment duration ( P =0.38), or trial-qualifying event ( P =0.59). Risk of death from any cause or a cardiovascular cause did not differ between active treatment and control groups.

Conclusion—

In a pooled analysis of data from 9 trials, PAR-1 antagonist therapy was associated with an increased risk for intracranial hemorrhage.