Dyspnea-Related Ticagrelor Discontinuation After Percutaneous Coronary Intervention.

BACKGROUND: Nearly 20% of patients on ticagrelor experience dyspnea, which may lead to treatment discontinuation in up to one-third of cases. OBJECTIVES: The authors sought to evaluate the incidence, predictors, and outcomes of dyspnea-related ticagrelor discontinuation after percutaneous coronary intervention (PCI). METHODS: In the TWILIGHT (Ticagrelor With Aspirin or Alone in High-Risk Patients After Coronary Intervention) trial, after 3 months of ticagrelor plus aspirin, patients were maintained on ticagrelor and randomized to aspirin or placebo for 1 year. The occurrence of dyspnea associated with ticagrelor discontinuation was evaluated among all patients enrolled in the trial. A landmark analysis was performed at 3 months after PCI, that is, the time of randomization. Predictors of dyspnea-related ticagrelor discontinuation were obtained from multivariable Cox regression with stepwise selection of candidate variables. RESULTS: The incidence of dyspnea-related ticagrelor discontinuation was 6.4% and 9.1% at 3 and 15 months after PCI, respectively. Independent predictors included Asian race (lower risk), smoking, prior PCI, hypercholesterolemia, prior coronary artery bypass, peripheral artery disease, obesity, and older age. Among 179 patients who discontinued ticagrelor because of dyspnea after randomization, ticagrelor monotherapy was not associated with a higher risk of subsequent ischemic events (composite of all-cause death, myocardial infarction, or stroke) compared with ticagrelor plus aspirin (5.0% vs 7.1%; P = 0.566). CONCLUSIONS: In the TWILIGHT trial, dyspnea-related ticagrelor discontinuation occurred in almost 1 in 10 patients and tended to occur earlier rather than late after PCI. Several demographic and clinical conditions predicted its occurrence, and their assessment may help identify subjects at risk for therapy nonadherence.

Acute Coronary Syndromes Among Patients with Prior Coronary Artery Bypass Surgery.

PURPOSE OF REVIEW: Acute coronary syndromes (ACS) often occur in individuals with prior coronary artery bypass graft surgery (CABG). Our goal was to describe the prevalence, clinical characteristics, prognosis, and treatment strategies in this group of patients. RECENT FINDINGS: Studies demonstrate that both acute and long-term major adverse cardiovascular outcomes are increased in patients with ACS and prior CABG compared to those without CABG. Much of this risk is attributed to the greater comorbid conditions present in patients with prior CABG. Data regarding optimal management of ACS in patients with prior CABG are limited, but most observational studies favor an early invasive approach for treatment. Native vessel percutaneous coronary intervention (PCI), if feasible, is generally preferred to bypass graft PCI. Patients with ACS and prior CABG represent a high-risk group of individuals, and implementing optimal preventive and treatment strategies are critically important to reduce the risk.

Ticagrelor with and without aspirin in patients with a prior coronary artery bypass graft undergoing percutaneous coronary intervention: the TWILIGHT-CABG study.

BACKGROUND: Prior coronary artery bypass graft surgery (CABG) patients undergoing percutaneous coronary intervention (PCI) are often older and present with multiple comorbidities. Ticagrelor monotherapy after a short course of dual antiplatelet therapy (DAPT) has emerged as an effective bleeding-avoidance strategy among high-risk patients. AIMS: We aimed to examine the effects of ticagrelor with or without aspirin in prior CABG patients undergoing PCI within the TWILIGHT trial. METHODS: After 3 months of ticagrelor plus aspirin, patients were randomised to either aspirin or placebo, in addition to ticagrelor, for 12 months and compared by prior CABG status. The primary endpoint was Bleeding Academic Research Consortium (BARC) type 2, 3 or 5 bleeding. The key secondary endpoint was all-cause death, myocardial infarction (MI), or stroke. RESULTS: Out of 7,119 patients, a total of 703 (10.8%) patients had prior CABG within the randomised cohort. Prior CABG patients had more comorbidities and a higher incidence of BARC type 2, 3, or 5 bleeding and death, MI or stroke at 1 year after randomisation, compared with patients without prior CABG. Ticagrelor monotherapy was associated with significantly less BARC 2, 3, or 5 bleeding among prior CABG patients compared with DAPT (4.9% vs 9.6%, hazard ratio [HR] 0.50, 95% confidence interval [CI]: 0.28 to 0.90; pinteraction=0.676) and similar rates of death, MI or stroke (10.0% vs 8.7%, HR 1.14, 95% CI: 0.70 to 1.87; pinteraction=0.484). When comparing target vessel type, treatment effects were consistent among graft- and native-vessel interventions. CONCLUSIONS: In high-risk patients with prior CABG, ticagrelor monotherapy reduced bleeding without compromising ischaemic outcomes compared with ticagrelor plus aspirin.

Updated Expert Consensus Statement on Platelet Function and Genetic Testing for Guiding P2Y12 Receptor Inhibitor Treatment in Percutaneous Coronary Intervention.

Dual-antiplatelet therapy (DAPT) with aspirin and a P2Y12 receptor inhibitor is the standard treatment for patients undergoing percutaneous coronary intervention. The availability of different P2Y12 receptor inhibitors (clopidogrel, prasugrel, ticagrelor) with varying levels of potency has enabled physicians to contemplate individualized treatment regimens, which may include escalation or de-escalation of P2Y12-inhibiting therapy. Indeed, individualized and alternative DAPT strategies may be chosen according to the clinical setting (stable coronary artery disease vs. acute coronary syndrome), the stage of the disease (early- vs. long-term treatment), and patient risk for ischemic and bleeding complications. A tailored DAPT approach may be potentially guided by platelet function testing (PFT) or genetic testing. Although the routine use of PFT or genetic testing in percutaneous coronary intervention-treated patients is not recommended, recent data have led to an update in guideline recommendations that allow considering selective use of PFT for DAPT de-escalation. However, guidelines do not expand on when to implement the selective use of such assays into decision making for personalized treatment approaches. Therefore, an international expert consensus group of key leaders from North America, Asia, and Europe with expertise in the field of antiplatelet treatment was convened. This document updates 2 prior consensus papers on this topic and summarizes the contemporary updated expert consensus recommendations for the selective use of PFT or genotyping in patients undergoing percutaneous coronary intervention.

Dual-Antiplatelet Therapy Cessation and Cardiovascular Risk in Relation to Age: Analysis From the PARIS Registry.

OBJECTIVES: The aim of this study was to examine the association between dual-antiplatelet therapy (DAPT) cessation and cardiovascular risk after percutaneous coronary intervention in relation to age. BACKGROUND: Examination of outcomes by age after percutaneous coronary intervention is relevant given the aging population. METHODS: Two-year clinical outcomes, incidence, and effect of DAPT cessation on outcomes were compared by ages ≤55, 56 to 74, and ≥75 years from the PARIS (Patterns of Non-Adherence to Antiplatelet Regimens in Stented Patients) registry. DAPT cessation included physician-recommended discontinuation, interruption for surgery, and disruption (from noncompliance or bleeding). Clinical endpoints were major adverse cardiac events (MACE) (a composite of cardiac death, definite or probable stent thrombosis, spontaneous myocardial infarction, or clinically indicated target lesion revascularization), a secondary restrictive definition of MACE (MACE2) excluding target lesion revascularization, and bleeding. RESULTS: A total of 1,192 patients (24%) were ≤55 years, 2,869 (57%) were 56 to 74 years, and 957 (19%) were ≥75 years of age. Patients ≥75 years of age had higher DAPT cessation rates and increased risk for MACE2, death, cardiac death, and bleeding compared with younger patients. Discontinuation and interruption were not associated with increased cardiovascular risk across age groups, whereas disruption was associated with increased risk for MACE and MACE2 in younger patients but not in patients ≥75 years of age (p for trend <0.05). CONCLUSIONS: Nonadherence and outcomes vary by age, with patients ≥75 years having the highest DAPT cessation rates. We observed no association between outcomes and DAPT cessation in patients ≥75 years, whereas discontinuation was associated with lower MACE rates and disruption with increased MACE rates in patients <75 years.

Hybrid coronary revascularization: Time for a new comparator?

The present meta-analysis found no significant difference between hybrid coronary revascularization (HCR) and bypass surgery (CABG) regarding intermediate-term major adverse cardiac and cerebrovascular events. HCR is feasible, historically with higher revascularization rates but less perioperative morbidity With a comparable frequency of repeat revascularization between current-generation drug-eluting stents and CABG, future trials of HCR are considering multi-vessel PCI as the new comparator.

Incidence, Patterns, and Associations Between Dual-Antiplatelet Therapy Cessation and Risk for Adverse Events Among Patients With and Without Diabetes Mellitus Receiving Drug-Eluting Stents: Results From the PARIS Registry.

OBJECTIVES: The aim of this study was to examine the frequency and clinical impact of different cessation patterns of dual-antiplatelet therapy (DAPT) after percutaneous coronary intervention with drug-eluting stents among patients with and those without diabetes mellitus (DM). BACKGROUND: Early DAPT suspension after percutaneous coronary intervention increases the risk for major adverse cardiac events. However, temporal variability in risk and relation to DAPT cessation patterns among patients with DM remain unclear. METHODS: Using data from the PARIS (Patterns of Non-Adherence to Anti-Platelet Regimens in Stented Patients) registry, 1,430 patients with DM (34%) and 2,777 without DM (66%) treated with drug-eluting stents were identified. DAPT cessation modes were classified as temporary interruption (<14 days), disruption because of bleeding or poor compliance, and physician-recommended discontinuation. RESULTS: During 2-year follow-up, DM was associated with an increased risk for thrombotic events but a similar risk for bleeding. The cumulative incidence of DAPT cessation was significantly lower in patients with versus those without DM (50.1% vs. 55.4%; p < 0.01), driven largely by less frequent physician-guided discontinuation beyond 1 year. In contrast, 2-year rates of interruption and disruption were similar between groups. When DAPT was interrupted or discontinued under physician guidance, the risk for major adverse cardiac events was unchanged compared with patients with DM on uninterrupted DAPT. Conversely, when DAPT was disrupted, the risk for major adverse cardiac events increased compared with uninterrupted DAPT, regardless of diabetic status, with no evidence of statistical interaction. CONCLUSIONS: DAPT cessation patterns vary according to diabetic status, with less frequent physician-guided discontinuation among patients with DM. The presence of DM does not emerge as a modifier of cardiovascular risk after DAPT cessation.

Sex-Based Differences in Cessation of Dual-Antiplatelet Therapy Following Percutaneous Coronary Intervention With Stents.

OBJECTIVES: The aim of this study was to compare the incidence and impact of cessation of dual-antiplatelet therapy (DAPT) in women and men treated with percutaneous coronary intervention. BACKGROUND: Nonadherence to cardiovascular medications and female sex are associated with worse outcomes. However, the patterns and impact of DAPT cessation in women compared with men following percutaneous coronary intervention have not been studied. METHODS: Baseline characteristics, patterns of DAPT cessation, and 2-year clinical outcomes were compared in 5,031 patients (1,279 women, 3,739 men) enrolled following successful percutaneous coronary intervention with stents in the PARIS (Patterns of Non-Adherence to Antiplatelet Regimens in Stented Patients) study. DAPT cessation was adjudicated as physician-guided discontinuation, interruption for surgery, or disruption due to bleeding or noncompliance. Clinical endpoints were major adverse cardiac events (a composite of cardiac death, definite or probable stent thrombosis, spontaneous myocardial infarction, or clinically indicated target lesion revascularization), a second restricted definition of major adverse cardiac events excluding target lesion revascularization, and bleeding. RESULTS: DAPT cessation was more common in women than men (59.1% vs. 55.9%, p = 0.007) and comprised increased rates of discontinuation, disruption for bleeding, and disruption due to noncompliance. The impact of DAPT cessation was similar regardless of sex and varied according the mode; in particular, disruption was associated with increased risk for both ischemic and bleeding events. After adjusting for differences in baseline and treatment characteristics as well as DAPT cessation events, female sex remained an independent predictor of bleeding but not of ischemic events. CONCLUSIONS: DAPT cessation was more common in women, but its impact was similar in women and men. Female sex was an independent predictor of bleeding but not of ischemic events after adjustment for differences in DAPT cessation and baseline and treatment characteristics.

Validation of BARC Bleeding Criteria in Patients With Acute Coronary Syndromes: The TRACER Trial.

BACKGROUND: The Bleeding Academic Research Consortium (BARC) scale has been proposed to standardize bleeding endpoint definitions and reporting in cardiovascular trials. Validation in large cohorts of patients is needed. OBJECTIVES: This study sought to investigate the relationship between BARC-classified bleeding and mortality and compared its prognostic value against 2 validated bleeding scales: TIMI (Thrombolysis In Myocardial Infarction) and GUSTO (Global Use of Strategies to Open Occluded Arteries). METHODS: We analyzed bleeding in 12,944 patients with acute coronary syndromes without ST-segment elevation, with or without early invasive strategy. The main outcome measure was all-cause death. RESULTS: During follow-up (median: 502 days), noncoronary artery bypass graft (CABG) bleeding occurred in 1,998 (15.4%) patients according to BARC (grades 2, 3, or 5), 484 (3.7%) patients according to TIMI minor/major, and 514 (4.0%) patients according to GUSTO moderate/severe criteria. CABG-related bleeding (BARC 4) occurred in 155 (1.2%) patients. Patients with BARC (2, 3, or 4) bleeding had a significant increase in risk of death versus patients without bleeding (BARC 0 or 1); the hazard was highest in the 30 days after bleeding (hazard ratio: 7.35; 95% confidence interval: 5.59 to 9.68; p < 0.0001) and remained significant up to 1 year. The hazard of mortality increased progressively with non-CABG BARC grades. BARC 4 bleeds were significantly associated with mortality within 30 days (hazard ratio: 10.05; 95% confidence interval: 5.41 to 18.69; p < 0.0001), but not thereafter. Inclusion of BARC (2, 3, or 4) bleeding in the 1-year mortality model with baseline characteristics improved it to an extent comparable to TIMI minor/major and GUSTO moderate/severe bleeding. CONCLUSIONS: In patients with acute coronary syndromes without ST-segment elevation, bleeding assessed with the BARC scale was significantly associated with risk of subsequent death up to 1 year after the event and risk of mortality increased gradually with higher BARC grades. Our results support adoption of the BARC bleeding scale in ACS clinical trials. (Trial to Assess the Effects of Vorapaxar [SCH 530348; MK-5348] in Preventing Heart Attack and Stroke in Participants With Acute Coronary Syndrome [TRACER] [Study P04736]; NCT00527943).

Coronary Thrombosis and Major Bleeding After PCI With Drug-Eluting Stents: Risk Scores From PARIS.

BACKGROUND: Dual-antiplatelet therapy with aspirin and clopidogrel after percutaneous coronary intervention reduces the risk for coronary thrombotic events (CTEs) at the expense of increasing risk for major bleeding (MB). Metrics to accurately predict the occurrence of each respective event and inform clinical decision making are lacking. OBJECTIVES: The aim of this study was to develop and validate separate models to predict risks for out-of-hospital thrombotic and bleeding events after percutaneous coronary intervention with drug-eluting stents. METHODS: Using data from 4,190 patients treated with drug-eluting stents and enrolled in the PARIS (Patterns of Non-Adherence to Anti-Platelet Regimen in Stented Patients) registry, separate risk scores were developed to predict CTE (defined as the composite of stent thrombosis or myocardial infarction) and MB (defined as the occurrence of a Bleeding Academic Research Consortium type 3 or 5 bleed). External validation was performed in the ADAPT-DES (Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents) registry. RESULTS: Over 2 years, CTEs occurred in 151 patients (3.8%) and MB in 133 (3.3%). Independent predictors of CTEs included acute coronary syndrome, prior revascularization, diabetes mellitus, renal dysfunction, and current smoking. Independent predictors of MB included older age, body mass index, triple therapy at discharge, anemia, current smoking, and renal dysfunction. Each model displayed moderate levels of discrimination and adequate calibration. CONCLUSIONS: Simple risk scores of baseline clinical variables may be useful to predict risks for ischemic and bleeding events after PCI with DES, thereby facilitating clinical decisions surrounding the optimal duration of DAPT. (Patterns of Non-Adherence to Anti-Platelet Regimen in Stented Patients [PARIS]; NCT00998127).

Efficacy and Safety of Vorapaxar in Non-ST-Segment Elevation Acute Coronary Syndrome Patients Undergoing Noncardiac Surgery.

BACKGROUND: Perioperative antiplatelet agents potentially increase bleeding after non-ST-segment elevation (NSTE) acute coronary syndromes (ACS). The protease-activated receptor 1 antagonist vorapaxar reduced cardiovascular events and was associated with increased bleeding versus placebo in NSTE ACS, but its efficacy and safety in noncardiac surgery (NCS) remain unknown. We aimed to evaluate ischemic, bleeding, and long-term outcomes of vorapaxar in NCS after NSTE ACS. METHODS AND RESULTS: In the TRACER trial, 2202 (17.0%) patients underwent major or minor NCS after NSTE ACS over 1.5 years (median); continuing study treatment perioperatively was recommended. The primary ischemic end point for this analysis was cardiovascular death, myocardial infarction, stent thrombosis, or urgent revascularization within 30 days of NCS. Safety outcomes included 30-day NCS bleeding and GUSTO moderate/severe bleeding. Overall, 1171 vorapaxar and 1031 placebo patients underwent NCS. Preoperative aspirin and thienopyridine use was 96.8% versus 97.7% (P=0.235) and 89.1% versus 86.1% (P=0.036) for vorapaxar versus placebo, respectively. Within 30 days of NCS, no differences were observed in the primary ischemic end point between vorapaxar and placebo groups (3.4% versus 3.9%; adjusted odds ratio 0.81, 95% CI 0.50 to 1.33, P=0.41). Similarly, no differences in NCS bleeding (3.9% versus 3.4%; adjusted odds ratio 1.41, 95% CI 0.87 to 2.31, P=0.17) or GUSTO moderate/severe bleeding (4.2% versus 3.7%; adjusted odds ratio 1.15, 95% CI, 0.72 to 1.83, P=0.55) were observed. In a 30-day landmarked analysis, NCS patients had a higher long-term risk of the ischemic end point (adjusted hazard ratio 1.62, 95% CI 1.33 to 1.97, P<0.001) and GUSTO moderate/severe bleeding (adjusted hazard ratio 5.63, 95% CI 3.98 to 7.97, P<0.001) versus patients who did not undergo NCS, independent of study treatment. CONCLUSION: NCS after NSTE ACS is common and associated with more ischemic outcomes and bleeding. Vorapaxar after NSTE ACS was not associated with increased perioperative ischemic or bleeding events in patients undergoing NCS.

PAR1 antagonists inhibit thrombin-induced platelet activation whilst leaving the PAR4-mediated response intact.

Thrombin-induced platelet activation is initiated by PAR1 and PAR4 receptors. Vorapaxar, a PAR1 antagonist, has been assessed in patients with acute coronary syndromes (ACS) and stable atherosclerotic disease in addition to standard-of-care treatment. In clinical trials, vorapaxar has been observed to reduce the frequency of ischaemic events in some subgroups though in others has increased the frequency of bleeding events. Among patients undergoing CABG surgery, which is associated with excess thrombin generation, bleeding was not increased. The aim of these studies was to investigate the effects of selective PAR1 antagonism on thrombin-induced platelet activation in patients receiving vorapaxar or placebo in the TRACER trial and to explore the roles of PAR1 and PAR4 in thrombin-induced platelet activation in healthy volunteers. ACS patients receiving vorapaxar or placebo in the TRACER trial were studied at baseline and 4 hours, 1 and 4 months during drug administration. Thrombin-induced calcium mobilisation in platelet-rich plasma was assessed by flow cytometry. In vitro studies were performed in healthy volunteers using the PAR1 antagonist SCH79797 or PAR4 receptor desensitisation. Vorapaxar treatment significantly inhibited thrombin-induced calcium mobilisation, leaving a residual, delayed response. These findings were consistent with calcium mobilisation mediated via the PAR4 receptor and were reproduced in vitro using SCH79797. PAR4 receptor desensitization, in combination with SCH79797, completely inhibited thrombin-induced calcium mobilisation confirming that the residual calcium mobilisation was mediated via PAR4. In conclusion vorapaxar selectively antagonises the PAR1-mediated component of thrombin-induced platelet activation, leaving the PAR4-mediated response intact, which may explain why vorapaxar is well tolerated in patients undergoing CABG surgery since higher thrombin levels in this setting may override the effects of PAR1 antagonism through PAR4 activation, thus preserving haemostasis. Further assessment may be warranted.

Effects of vorapaxar on platelet reactivity and biomarker expression in non-ST-elevation acute coronary syndromes. The TRACER Pharmacodynamic Substudy.

Vorapaxar is an antagonist of the protease activated receptor-1 (PAR-1), the principal platelet thrombin receptor. The Thrombin Receptor Antagonist for Clinical Event Reduction (TRACER) trial evaluated vorapaxar compared to placebo in non-ST-elevation (NSTE)-acute coronary syndrome (ACS) patients. It was the study's objective to assess the pharmacodynamic effects of vorapaxar versus placebo that included aspirin or a thienopyridine or, frequently, a combination of both agents in NSTE-ACS patients. In a substudy involving 249 patients, platelet aggregation was assessed by light transmittance aggregometry (LTA) in 85 subjects (41 placebo, 44 vorapaxar) using the agonists thrombin receptor activating peptide (TRAP, 15 µM), adenosine diphosphate (ADP, 20 µM), and the combination of collagen-related peptide (2.5 µg/ml) + ADP (5 µM) + TRAP (15 µM) (CAT). VerifyNow® IIb/IIIa and vasodilator-stimulated phosphoprotein (VASP) phosphorylation assays were performed, and platelet PAR-1 expression, plasma platelet/endothelial and inflammatory biomarkers were determined before and during treatment. LTA responses to TRAP and CAT and VerifyNow results were markedly inhibited by vorapaxar. Maximal LTA response to TRAP (median, interquartile range) 2 hours post loading dose: placebo 68% (53-75%) and vorapaxar 3% (2-6%), p<0.0001. ADP inhibition was greater in the vorapaxar group at 4 hours and one month (p<0.01). In contrast to the placebo group, PAR-1 receptor number in the vorapaxar group at one month was significantly lower than the baseline (179 vs 225; p=0.004). There were significant changes in selected biomarker levels between the two treatment groups. In conclusion, vorapaxar caused a potent inhibition of PAR-1-mediated platelet aggregation. Further studies are needed to explore vorapaxar effect on P2Y12 inhibition, PAR-1 expression and biomarkers and its contribution to clinical outcomes.

Vorapaxar in acute coronary syndrome patients undergoing coronary artery bypass graft surgery: subgroup analysis from the TRACER trial (Thrombin Receptor Antagonist for Clinical Event Reduction in Acute Coronary Syndrome).

OBJECTIVES: This study evaluated effects of protease-activated receptor-1 antagonist vorapaxar (Merck, Whitehouse Station, New Jersey) versus placebo among the TRACER (Thrombin Receptor Antagonist for Clinical Event Reduction in Acute Coronary Syndrome) study patients with non-ST-segment elevation acute coronary syndromes undergoing coronary artery bypass grafting (CABG). BACKGROUND: Platelet activation may play a key role in graft occlusion, and antiplatelet therapies may reduce ischemic events, but perioperative bleeding risk remains a major concern. Although the TRACER study did not meet the primary quintuple composite outcome in the overall population with increased bleeding, an efficacy signal with vorapaxar was noted on major ischemic outcomes, and preliminary data suggest an acceptable surgical bleeding profile. We aimed to assess efficacy and safety of vorapaxar among CABG patients. METHODS: Associations between treatment and ischemic and bleeding outcomes were assessed using time-to-event analysis. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using the Cox hazards model. Event rates were estimated using the Kaplan-Meier method. RESULTS: Among 12,944 patients, 1,312 (10.1%) underwent CABG during index hospitalization, with 78% on the study drug at the time of surgery. Compared with placebo CABG patients, vorapaxar-treated patients had a 45% lower rate of the primary endpoint (i.e., a composite of death, myocardial infarction, stroke, recurrent ischemia with rehospitalization, or urgent coronary revascularization during index hospitalization) (HR: 0.55; 95% CI: 0.36 to 0.83; p = 0.005), with a significant interaction (p = 0.012). The CABG-related Thrombolysis In Myocardial Infarction major bleeding was numerically higher with vorapaxar, but not significantly different between vorapaxar and placebo (9.7% vs. 7.3%; HR: 1.36; 95% CI: 0.92 to 2.02; p = 0.12), with no excess in fatal bleeding (0% vs. 0.3%) or need for reoperation (4.7% vs. 4.6%). CONCLUSIONS: In non-ST-segment elevation acute coronary syndrome patients undergoing CABG, vorapaxar was associated with a significant reduction in ischemic events and no significant increase in major CABG-related bleeding. These data show promise for protease-activated receptor 1 antagonism in patients undergoing CABG and warrant confirmatory evidence in randomized trials. (Trial to Assess the Effects of SCH 530348 in Preventing Heart Attack and Stroke in Patients With Acute Coronary Syndrome [TRA·CER] [Study P04736AM3]; NCT00527943).

Cessation of dual antiplatelet treatment and cardiac events after percutaneous coronary intervention (PARIS): 2 year results from a prospective observational study.

BACKGROUND: Dual antiplatelet therapy (DAPT) cessation increases the risk of adverse events after percutaneous coronary intervention (PCI). Whether risk changes over time, depends on the underlying reason for DAPT cessation, or both is unknown. We assessed associations between different modes of DAPT cessation and cardiovascular risk after PCI. METHODS: The PARIS (patterns of non-adherence to anti-platelet regimens in stented patients) registry is a prospective observational study of patients undergoing PCI with stent implantation in 15 clinical sites in the USA and Europe between July 1, 2009, and Dec 2, 2010. Adult patients (aged 18 years or older) undergoing successful stent implantation in one or more native coronary artery and discharged on DAPT were eligible for enrolment. Patients were followed up at months 1, 6, 12, and 24 after implantation. Prespecified categories for DAPT cessation included physician-recommended discontinuation, brief interruption (for surgery), or disruption (non-compliance or because of bleeding). All adverse events and episodes of DAPT cessation were independently adjudicated. Using Cox models with time-varying covariates, we examined the effect of DAPT cessation on major adverse events (MACE [composite of cardiac death, definite or probable stent thrombosis, myocardial infarction, or target-lesion revascularisation]). Incidence rates for DAPT cessation and adverse events were calculated as Kaplan-Meier estimates of time to the first event. This study is registered with ClinicalTrials.gov, number NCT00998127. FINDINGS: We enrolled 5031 patients undergoing PCI, including 5018 in the final study population. Over 2 years, the overall incidence of any DAPT cessation was 57·3%. Rate of any discontinuation was 40·8%, of interruption was 10·5%, and of disruption was 14·4%. The corresponding overall 2 year MACE rate was 11·5%, most of which (74%) occurred while patients were taking DAPT. Compared with those on DAPT, the adjusted hazard ratio (HR) for MACE due to interruption was 1·41 (95% CI 0·94-2·12; p=0·10) and to disruption was 1·50 (1·14-1.97; p=0·004). Within 7 days, 8-30 days, and more than 30 days after disruption, adjusted HRs were 7·04 (3·31-14·95), 2·17 (0·97-4·88), and 1·3 (0·97-1·76), respectively. By contrast with patients who remained on DAPT, those who discontinued had lower MACE risk (0·63 [0·46-0·86]). Results were similar after excluding patients receiving bare metal stents and using an alternative MACE definition that did not include target lesion revascularisation. INTERPRETATION: In a real-world setting, for patients undergoing PCI and discharged on DAPT, cardiac events after DAPT cessation depend on the clinical circumstance and reason for cessation and attenuates over time. While most events after PCI occur in patients on DAPT, early risk for events due to disruption is substantial irrespective of stent type. FUNDING: Bristol-Myers Squibb and Sanofi-Aventis.

Drug-drug interactions in cardiovascular catheterizations and interventions.

Patients presenting for invasive cardiovascular procedures are frequently taking a variety of medications aimed to treat risk factors related to heart and vascular disease. During the procedure, antithrombotic, sedative, and analgesic medications are commonly needed, and after interventional procedures, new medications are often added for primary and secondary prevention of ischemic events. In addition to these prescribed medications, the use of over-the-counter drugs and supplements continues to rise. Most elderly patients, for example, are taking 5 or more prescribed medications and 1 or more supplements, and they often have some degree of renal insufficiency. This polypharmacy might result in drug-drug interactions that affect the balance of thrombotic and bleeding events during the procedure and during long-term treatment. Mixing of anticoagulants, for instance, might lead to periprocedural bleeding, and this is associated with an increase in long-term adverse events. Furthermore, the range of possible interactions with thienopyridine antiplatelets is of concern, because these drugs are essential to immediate and extended interventional success. The practical challenges in the field are great-some drug-drug interactions are likely present yet not well understood due to limited assays, whereas other interactions have well-described biological effects but seem to be more theoretical, because there is little to no clinical impact. Interventional providers need to be attentive to the potential for drug-drug interaction, the associated harm, and the appropriate action, if any, to minimize the potential for medication-related adverse events. This review will focus on drug-drug interactions that have the potential to affect procedural success, either through increases in immediate complications or compromising longer-term outcome.