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Visual Abstract, Highlights • Our study supports the feasibility of using rapid CYP2C19 genotyping among both patients with stable and acute coronary syndrome undergoing diagnostic coronary angiography, with intent to undergo ad hoc PCI, in real-world clinical practice. • Rapid bedside genetic testing assay allows for very rapid turnaround times of results, with patients approached the same day of their procedure and availability of CYP2C19 genotypes within 1 h of sampling and before patients undergoing PCI. • Among carriers of CYP2C19 loss-of-function alleles undergoing PCI there were no differences in levels of platelet inhibition between prasugrel and ticagrelor (loading and maintenance dosing)., Summary The feasibility of rapid genetic testing in patients undergoing percutaneous coronary intervention (PCI) and the comparison of the pharmacodynamic effects of prasugrel versus ticagrelor among carriers of cytochrome P450 2C19 loss-of-function alleles treated with PCI has been poorly explored. Rapid genetic testing using the Spartan assay was shown to be feasible and provides results in a timely fashion in a real-world setting of patients undergoing coronary angiography (n = 781). Among patients (n = 223, 28.5%), carriers of at least 1 loss-of-function allele treated with PCI (n = 65), prasugrel, and ticagrelor achieve similar levels of platelet inhibition. (A Pharmacodynamic Study Comparing Prasugrel Versus Ticagrelor in Patients Undergoing PCI With CYP2C19 Loss-of-function [NCT02065479])

Aims Dual pathway inhibition (DPI) by adding a vascular dose of rivaroxaban to a single antiplatelet agent has emerged as a promising antithrombotic strategy. However, in most studies the antiplatelet agent of choice used in adjunct to a vascular dose of rivaroxaban was aspirin, and data on a P2Y12 inhibitor and how this DPI regimen compares with standard dual antiplatelet therapy (DAPT) are limited. Methods and results This investigation was a substudy analysis conducted in selected cohorts of patients with stable atherosclerotic disease enrolled from a larger prospective, open-label, parallel-group pharmacodynamic (PD) study. We analysed data from 40 patients treated with either clopidogrel- or ticagrelor-based DAPT first, and clopidogrel- or ticagrelor-based DPI thereafter. PD measures explored key pathways involved in thrombus formation and included markers of (1) P2Y12 reactivity, (2) platelet-mediated global thrombogenicity, (3) cyclooxygenase-1 activity, (4) thrombin receptor-activating peptide (TRAP)-induced platelet aggregation, (5) tissue factor (TF)-induced platelet aggregation, and (6) thrombin generation. Compared with DAPT, on a background of the same P2Y12 inhibitor (clopidogrel or ticagrelor), DPI was associated with reduced thrombin generation, increased markers of cyclooxygenase-1 activity and TRAP-induced platelet aggregation, and no differences in markers of P2Y12 signalling, platelet-mediated global thrombogenicity, and TF-induced platelet aggregation. In an analysis according to P2Y12 inhibitor type, ticagrelor reduced markers of platelet-mediated global thrombogenicity, P2Y12 signalling, and rates of high platelet reactivity compared with clopidogrel. Conclusion Compared with DAPT with aspirin and a P2Y12 inhibitor, the use of a P2Y12 inhibitor in adjunct to a vascular dose of rivaroxaban as part of a DPI strategy is associated with similar effects on platelet-mediated global thrombogenicity but reduced thrombin generation. A DPI strategy with ticagrelor is associated with enhanced antithrombotic efficacy, the clinical implications of which warrant larger scale investigations. Clinical trial registration ClinicalTrials.gov identifier: NCT03718429.

Aim Inhibition of thrombin-mediated signaling processes using a vascular dose of rivaroxaban in adjunct to antiplatelet therapy, known as dual-pathway inhibition (DPI), reduces atherothrombotic events in patients with stable atherosclerotic disease. However, there are limited data on the pharmacodynamic (PD) effects of this strategy and how it compares to standard dual antiplatelet therapy (DAPT). Methods and Results This investigation was conducted in selected cohorts of patients (n = 40) with stable atherosclerotic disease—enrolled within a larger prospective, open-label, parallel-group PD study—who were treated with either aspirin plus clopidogrel (DAPT), aspirin plus rivaroxaban 2.5 mg/bid (DPI), or DAPT plus rivaroxaban 2.5 mg/bid. Multiple PD assays providing a comprehensive assessment of markers of thrombosis were used. PD endpoints included platelet-mediated global thrombogenicity measured by light transmittance aggregometry (LTA) following stimuli with CATF (collagen-related peptide + adenosine diphosphate [ADP] + tissue factor [TF]), markers of P2Y12 reactivity, markers of platelet aggregation using LTA following several stimuli (arachidonic acid, ADP, collagen, TF, and thrombin receptor-activating peptide [TRAP]), thrombin generation, and thrombus formation. There was no difference in platelet-mediated global thrombogenicity between groups. Rivaroxaban significantly reduced thrombin generation and was associated with a trend toward reduced TF-induced platelet aggregation. Clopidogrel-based treatments reduced markers of P2Y12 signaling and TRAP-induced platelet aggregation. There were no differences between groups on markers of cyclooxygenase-1-mediated activity. Conclusion Compared with DAPT, DPI does not result in any differences in platelet-mediated global thrombogenicity, but reduces thrombin generation. These PD observations suggest that modulating thrombin generation—by means of factor Xa inhibition—in adjunct to antiplatelet therapy provides effective antithrombotic effects, supporting the efficacy and safety findings of a DPI strategy observed in clinical trials.

Summary: Vorapaxar reduces thrombotic cardiovascular events at the expense of increased bleeding. However, the differential pharmacodynamic (PD) effects of vorapaxar according to diabetes mellitus (DM) status are unknown. Moreover, although withdrawal of aspirin has emerged as a bleeding reduction strategy, the PD effects of stopping aspirin in patients treated with vorapaxar also are unknown. In this prospective PD investigation, vorapaxar was associated with reduced platelet-mediated thrombogenicity without affecting clot kinetics irrespective of DM status. However, platelet-mediated thrombogenicity increased after aspirin withdrawal, particularly among patients with DM. (Optimizing anti-Platelet Therapy In diabetes MellitUS-5 Study [OPTIMUS-5]; NCT02548650) Key Words: dual antiplatelet therapy, pharmacodynamics, platelets, thrombin, vorapaxar

In patients requiring dual antiplatelet therapy (DAPT) who also have an indication to be treated with oral anticoagulant (OAC) drugs, aspirin withdrawal reduces the risk of bleeding. There is limited data on the pharmacodynamic effects associated with adding a nonvitamin K antagonist OAC on a background of aspirin and a P2Y12 inhibitor as well as dropping aspirin. Seventy-five patients on DAPT (aspirin plus clopidogrel) were randomized to DAPT plus high-dose edoxaban (60 mg once daily, Group A), DAPT plus low-dose edoxaban (30 mg once daily, Group B), or DAPT only (Group C) for 10 ± 2 days (Phase I). Afterwards, Groups A and B interrupted aspirin and maintained clopidogrel plus edoxaban for 10 ± 2 days, while patients in Group C maintained DAPT (Phase II). Platelet aggregation and clot kinetics were assessed at baseline, end of Phase I, and end of Phase II using thrombelastography (TEG), light transmittance aggregometry (LTA), VerifyNow P2Y12, and serum thromboxane-B2. The primary endpoint was the comparison of maximum amplitude (MA) measured by TEG, a measure of clot strength, between patients on DAPT plus high-dose edoxaban and patients on DAPT only. Edoxaban prolonged in a dose-dependent manner speed of thrombin generation (TEG R; Group A: 7.7 [6.8–8.7] vs. Group B: 7.4 [6.4–8.5] vs. Group C: 6.3 [5.7–7.0]; p = 0.05) but did not affect other markers of clot kinetics, including TEG MA (Group A: 63 [61–64] vs. Group B: 65 [63–67] vs. Group C: 64 [63–65]; p = 0.10). After aspirin discontinuation, platelet reactivity assessed by LTA using thrombin receptor activating peptide as agonist increased to a greater extent with low-dose edoxaban. Stopping aspirin did not affect markers of P2Y12 reactivity and had no or marginal effects on clot kinetics, but increased markers sensitive to cyclooxygenase-1 blockade.

Objectives The aim of this study was to assess if intravenous methylnaltrexone can counteract the effects of morphine on the pharmacokinetic (PK) and pharmacodynamic (PD) profiles of ticagrelor. Background Morphine delays the onset of action of oral P2Y12 receptor inhibitors, including ticagrelor, by inhibiting gastric emptying and leading to delayed drug absorption. Methylnaltrexone is a peripheral opioid receptor antagonist that has the potential to prevent opioid-induced peripherally mediated side effects (e.g., gastric emptying inhibition) without affecting analgesia. Methods In this prospective, randomized, double-blind, placebo-controlled, crossover study, aspirin-treated patients with stable coronary artery disease (n = 30) were randomized to receive methylnaltrexone (0.3 mg/kg intravenous) or matching placebo. After methylnaltrexone or placebo administration, all patients received morphine (5 mg intravenous). This was followed 15 min later by a 180-mg loading dose of ticagrelor. Patients crossed over to the alternative study treatment after 7 ± 2 days of washout. PK and PD assessments were performed at 12 time points (6 pre- and 6 post-crossover). PK analysis included measurement of plasma levels of ticagrelor and its major active metabolite (AR-C124910XX). PD assessments included VerifyNow P2Y12, light transmittance aggregometry, and vasodilator-stimulated phosphoprotein. Results Only marginal changes in plasma levels of ticagrelor (and its major active metabolite) were observed with ticagrelor: maximum plasma concentration and area under the plasma concentration versus time curve from time 0 to the last measurable concentration were 38% and 30% higher, respectively, in patients receiving methylnaltrexone compared with those receiving placebo, but no differences in time to maximum plasma concentration were observed. There were no differences in P2Y12 reaction units by VerifyNow P2Y12 between groups at each time point, including 2 h (the primary endpoint; p = 0.261). Similarly, there were no differences in PD markers assessed by light transmittance aggregometry and vasodilator-stimulated phosphoprotein. Conclusions In patients with coronary artery disease receiving morphine, intravenous administration of the peripheral opioid receptor antagonist methylnaltrexone leads to only marginal changes in plasma levels of ticagrelor and its major metabolite, without affecting levels of platelet reactivity. (Effect of Methylnaltrexone on the PK/PD Profiles of Ticagrelor in Patients Treated With Morphine; NCT02403830)

Background: The platelet inhibitory effects induced by oral P2Y 12 receptor antagonists are delayed in patients with ST-segment–elevation myocardial infarction undergoing primary percutaneous coronary intervention (P-PCI). In turn, this leads to a gap in platelet inhibition, exposing patients to an increased risk of early thrombotic complications and underscoring the need to define strategies associated with more effective platelet inhibition in the peri–primary percutaneous coronary intervention period. Cangrelor is an intravenous P2Y 12 inhibitor with prompt and potent antiplatelet effects. However, to date, there are limited data on the effects of cangrelor used in combination with ticagrelor in patients undergoing primary percutaneous coronary intervention. Moreover, questions have emerged on the potential for drug–drug interactions during the transition from cangrelor to oral P2Y 12 inhibitors. Methods: This was a prospective, randomized, double-blind, placebo-controlled pharmacodynamic study conducted in patients undergoing primary percutaneous coronary intervention (n=50) who were randomized to treatment with either cangrelor or matching placebo (bolus followed by 2-hour infusion). All patients received ticagrelor 180-mg loading dose administered as crushed tablets at the time of cangrelor/placebo bolus administration. Pharmacodynamic analyses were performed at 8 time points. Pharmacodynamic effects were measured as P2Y 12 reaction units by VerifyNow and platelet reactivity index by vasodilator-stimulated phosphoprotein. Results: Compared with placebo, cangrelor was associated with reduced P2Y 12 reaction units as early as 5 minutes after bolus, which persisted during the entire duration of drug infusion, including at 30 minutes (63 [32–93] versus 214 [183–245]; mean difference, 152 [95% CI, 108–195]; P Conclusions: In patients undergoing primary percutaneous coronary intervention, cangrelor is an effective strategy to bridge the gap in platelet inhibition associated with the use of oral P2Y 12 inhibition induced by ticagrelor. Ticagrelor can be administered as a crushed formulation concomitantly with cangrelor without any apparent drug–drug interaction. The clinical implications of these pharmacodynamic findings warrant investigation in an adequately powered clinical trial. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT03247738

Aims Patients with diabetes mellitus (DM) and chronic kidney disease (CKD) are at increased risk of atherothrombotic events. Ticagrelor reduces ischaemic events compared to clopidogrel, with the greatest risk reduction in patients with both DM and CKD. How CKD status affects the pharmacodynamic (PD) and pharmacokinetic (PK) profiles of different ticagrelor maintenance dose regimens in patients with DM is unknown. Methods and results In this randomized, crossover study, patients with DM on treatment with dual antiplatelet therapy (aspirin and clopidogrel) were stratified according to CKD status and randomized to ticagrelor 90 or 60 mg bid. PK/PD assessments were performed at baseline, after 7–10 days of ticagrelor (peak and trough), and after 7–10 days of alternative ticagrelor regimen (peak and trough). PK assessments included plasma concentrations of ticagrelor and its major metabolite. PD assessments included vasodilator-stimulated phosphoprotein (VASP)–platelet reactivity index (PRI), VerifyNow P2Y12, and light transmittance aggregometry (LTA). A total of 92 patients with DM (CKD, n = 44; non-CKD, n = 48) were randomized. Levels of platelet reactivity were lower with the 90 mg compared with the 60 mg ticagrelor dose, which was statistically significant in non-CKD but not in CKD patients for most PD measures. There were no significant differences in the primary endpoint (trough levels of VASP–PRI following ticagrelor 90 mg dosing) between cohorts (31 ± 20 vs. 25 ± 14; P = 0.105). VerifyNow and LTA provided similar findings. PK assessments tracked PD profiles showing increased plasma concentrations of ticagrelor and its major metabolite in CKD compared to non-CKD patients. Conclusion In patients with DM, although ticagrelor maintenance dose regimens (60 and 90 mg) yield potent P2Y12 inhibition, levels of platelet reactivity tended to be higher and subject to broader variability in non-CKD compared with CKD patients. Clinical trial registration http://www.clinicaltrials.gov Unique Identifier: NCT02539160.

Background: Diabetes mellitus (DM) is a key risk factor for the development of chronic kidney disease (CKD) and patients having both risk factors have increased risk of atherothrombotic events, underscoring the importance of antiplatelet therapy. Ticagrelor reduces ischemic events compared with clopidogrel, with the greatest risk reduction in patients with both DM and CKD. However, how CKD status affects the pharmacodynamic (PD) and pharmacokinetic (PK) profiles of different ticagrelor dosing regimens in DM patients is unknown. Methods: This was a prospective, randomized, cross-over study testing the PD/PK profiles of ticagrelor 90mg bid and 60mg bid among DM patients with and without CKD. All patients had coronary artery disease and were on dual antiplatelet therapy with aspirin (81mg qd) and clopidogrel (75mg qd). PD and PK assessments were performed at 3 visits: baseline, after 7-10 days of ticagrelor therapy (pre-crossover; peak and trough), and after 7-10 days of alternative ticagrelor regimen (post-crossover; peak and trough). Results: A total of 92 patients were randomized (CKD-, n=48; CKD+, n=44). Platelet reactivity as assessed by multiple assays (VASP-PRI; VerifyNow P2Y12; LTA) was increased with 60mg compared with 90 mg, which was statistically significant in CKD- but not in CKD+ patients for most PD measures (Figure). Although trough levels of platelet reactivity were numerically lower in CKD+ patients compared with CKD-, there was no significant difference in the pre-defined primary endpoint (trough levels of VASP-PRI following ticagrelor 90 mg dosing) between DM subjects with and without CKD (31±20 vs 25±14; mean difference= 6.4; 95% CI: -1.1 to 14.3; p=0.105; primary endpoint; Figure). PK assessments tracked PD profiles. Conclusions: In patients with DM, platelet inhibition by ticagrelor is similar irrespective of CKD status. However, the PD effects of the 60mg ticagrelor regimen is reduced compared with the 90mg regimen in patients without CKD.

Background Vorapaxar as an adjunct to dual antiplatelet therapy ( DAPT ) reduces thrombotic events in patients with prior myocardial infarction at the expense of increased bleeding. Withdrawal of aspirin has emerged as a bleeding reduction strategy. The pharmacodynamic effects of vorapaxar with potent P2Y 12 inhibitors as well as the impact of dropping aspirin is unexplored and represented the aim of the VORA‐PRATIC (Vorapaxar Therapy in Patients With Prior Myocardial Infarction Treated With Newer Generation P2Y 12 Receptor Inhibitors Prasugrel and Ticagrelor) study. Methods and Results Post–myocardial infarction patients (n=130) on standard DAPT (aspirin+prasugrel or ticagrelor) were randomized to 1 of 3 arms: (1) triple therapy: aspirin+prasugrel/ticagrelor+vorapaxar; (2) dual therapy (drop aspirin): prasugrel/ticagrelor+vorapaxar; (3) DAPT : aspirin+prasugrel/ticagrelor. Pharmacodynamic assessments were performed at 3 time points (baseline and 7 and 30 days). Vorapaxar reduced CAT (collagen‐ADP‐TRAP)–induced platelet aggregation, a marker of platelet‐mediated global thrombogenicity (triple therapy versus DAPT at 30 days: mean difference=–27; 95% CI ,–35 to –19; P DAPT at 30 days: mean difference=–15; 95% CI ,–23 to –7; P P P 12 reactivity. Markers sensitive to aspirin‐induced effects increased ( P Conclusions In post–myocardial infarction patients treated with potent P2Y 12 inhibitors, vorapaxar reduces platelet‐driven global thrombogenicity, an effect that persisted, albeit attenuated, in the absence of aspirin and without affecting markers of P2Y 12 reactivity or clot kinetics. The clinical implications of these PD observations warrant future investigation. Registration URL : https://www.clini​caltr​ials.gov . Unique identifier: NCT 02545933.

Background: Switching between different classes of P2Y 12 inhibitors, including de-escalation from ticagrelor to clopidogrel, commonly occurs in clinical practice. However, the pharmacodynamic profiles of this strategy have been poorly explored. Methods: This was a prospective, randomized, open-label study conducted in patients on maintenance dosing (MD) of aspirin (81 mg/d) and clopidogrel (75 mg/d). After a 7-day run-in with ticagrelor (180 mg loading dose [LD] followed by 90 mg twice daily MD), patients (n=80) were randomized into 1 of 4 groups: group A, clopidogrel 600 mg LD 24 hours after the last MD of ticagrelor (C-600 mg-24h); group B, clopidogrel 600 mg LD 12 hours after the last MD of ticagrelor (C-600 mg-12h); group C, clopidogrel 75 mg/d MD 24 hours after the last MD of ticagrelor (C-75 mg-24h); and group D, ticagrelor 90 mg twice daily MD (T-90 mg twice daily). MD of the randomized treatment was maintained for 10±3 days. Pharmacodynamic assessments were performed at baseline, after run-in, and at 2, 24, 48, and 72 hours and 10 days with P2Y 12 reaction units by VerifyNow; platelet reactivity index was assessed by vasodilator-stimulated phosphoprotein; and maximal platelet aggregation was determined by light transmittance aggregometry. Results: T-90 mg twice daily led to lower platelet reactivity than any clopidogrel regimen using all assays at all time points. P2Y 12 reaction unit levels were similar between the C-600 mg-24h (group A) and the C-75 mg-24h (group C) ( P =0.29), including at 48 hours (primary end point; least mean difference, −6.9; 95% confidence interval, −38.1 to 24.3; P =0.66). P2Y 12 reaction unit levels were lower with C-600 mg-12h (group B) than with C-75 mg-24h (group C; P =0.024). Maximal platelet aggregation over time was lower with both C-600 mg-24h (group A; P =0.041) and C-600 mg-12h (group B; P =0.028) compared with C-75 mg-24h (group C). Platelet reactivity index profiles paralleled those observed with P2Y 12 reaction units. There were no pharmacodynamic differences for all tests between C-600 mg-24h (group A) and C-600 mg-12h (group B). In group C (C-75 mg-24h), platelet reactivity increased compared with baseline as early as 24 hours, reaching statistical significance at 48 and 72 hours and up to 10 days. These pharmacodynamic findings were delayed and blunted in magnitude with the administration of an LD, regardless of the timing of administration. Conclusions: De-escalation from ticagrelor to clopidogrel therapy is associated with an increase in platelet reactivity. The use of an LD before the initiation of an MD regimen of clopidogrel mitigates these observations, although this is not affected by the timing of its administration after ticagrelor discontinuation. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02287909.

Background Although clopidogrel is the most widely used P2Y12 inhibitor, loss-of-function (LOF) allelic variants located within the hepatic cytochrome P450 (CYP) 2C19 gene lead to attenuated bioactivation, increased rates of high platelet reactivity (HPR), and worse outcomes in patients undergoing percutaneous coronary intervention (PCI). Drug regulating authorities have suggested using alternative P2Y12 inhibitors (i.e., prasugrel or ticagrelor) in these patients. However, tailoring antiplatelet therapy in clinical practice according to results of genetic testing has been limited due to lack of access to promptly available results. Moreover, there are no head-to-head pharmacodynamic (PD) comparisons of prasugrel vs ticagrelor among patients with CYP2C19 LOF alleles. Purpose The aim of this study was to evaluate the feasibility of using rapid genetic testing in clinical practice and to compare the PD effects of prasugrel vs ticagrelor in patients undergoing PCI with CYP2C19 LOF alleles. Methods This was a prospective, randomized study conducted in patients with stable coronary artery disease and non-ST elevation acute coronary syndrome scheduled for left heart catheterization (LHC) with the intent to undergo PCI. Patients underwent rapid genetic testing using the Spartan RX assay, which defines CYP2C19 genetic status within 1 hour, allowing patients to be genotyped the same day of their LHC. Patients who were carriers of at least one LOF (*2 or *3) allele were randomized to receive either prasugrel [60mg loading dose (LD) - 10mg/day maintenance dose (MD)] or ticagrelor (180mg LD - 90mg b.i.d MD). Blood samples for PD analysis by VerifyNow were collected at 5 time points: baseline (prior to PCI), 30 minutes, 2 hours, 24 hours (or at hospital discharge whichever came first), and 1–4 weeks post-LD. All patients were treated with aspirin. The primary endpoint of our study was the non-inferiority in platelet reactivity, measured as PRU, at 24 hours of prasugrel vs ticagrelor in LOF allele carriers. Results A total of 781 consecutive patients scheduled for LHC were genotyped, of whom 223 (28.5%) were carriers of at least one LOF. Of these, 65 patients underwent PCI and randomized to prasugrel (n=32) vs ticagrelor (n=33). PRU levels at 24 hours were 33 vs 36 (prasugrel vs ticagrelor; mean difference = −3; 95% CI: −28 to 22; p=0.814) meeting the primary endpoint of non-inferiority. Both prasugrel and ticagrelor significantly reduced PRU to a similar extent with no differences between groups at all other time points (Figure). Accordingly, HPR rates were low and similar between groups. PRU by VerifyNow Conclusion Rapid genetic testing using the Spartan assay is feasible providing results in a timely fashion in a real-world clinical practice of patients undergoing PCI. Among patients with CYP2C19 LOF carrier status, prasugrel and ticagrelor are associated with similar levels of platelet inhibition. Acknowledgement/Funding Genetic testing was provided by Spartan RX

The platelet inhibitory effects induced by oral P2YThis was a prospective, randomized, double-blind, placebo-controlled pharmacodynamic study conducted in patients undergoing primary percutaneous coronary intervention (n=50) who were randomized to treatment with either cangrelor or matching placebo (bolus followed by 2-hour infusion). All patients received ticagrelor 180-mg loading dose administered as crushed tablets at the time of cangrelor/placebo bolus administration. Pharmacodynamic analyses were performed at 8 time points. Pharmacodynamic effects were measured as P2YCompared with placebo, cangrelor was associated with reduced P2YIn patients undergoing primary percutaneous coronary intervention, cangrelor is an effective strategy to bridge the gap in platelet inhibition associated with the use of oral P2YURL: https://www.clinicaltrials.gov . Unique identifier: NCT03247738.

Objectives This study tested whether intramyocardial (IM) administration of mobilized, purified autologous CD34 + cells would improve total exercise time (TET) and angina frequency in patients with refractory angina. Background IM administration of autologous CD34 + cells has been associated consistently with improvements in functional capacity and angina symptoms in early phase clinical trials. Methods RENEW (Efficacy and Safety of Targeted Intramyocardial Delivery of Auto CD34+ Stem Cells for Improving Exercise Capacity in Subjects With Refractory Angina) was a randomized, double-blind, multicenter trial comparing IM CD34 + administration with no intervention (open-label standard of care) or IM placebo injections (active control). The primary efficacy endpoint was change in TET at 12 months. Key secondary endpoints include changes in angina frequency at 3, 6, and 12 months, and TET at 3 and 6 months. The key safety analysis was the incidence of major adverse cardiovascular events through 24 months. Results The sponsor terminated the study for strategic considerations after enrollment of 112 of planned 444 patients. The difference in TET between patients treated with cell therapy versus placebo was 61.0 s at 3 months (95% confidence interval (CI): -2.9 to 124.8; p = 0.06), 46.2 s at 6 months (95% CI: -28.0 to 120.4; p = 0.22), and 36.6 s at 12 months (95% CI: -56.1 to 129.2; p = 0.43); angina frequency was improved at 6 months (relative risk: 0.63; p = 0.05). Autologous CD34 + cell therapy seemed to be safe compared with both open-label standard of care and active control (major adverse cardiovascular events 67.9% [standard of care], 42.9% (active control), 46.0% [CD34 + ]). Conclusions Due to early termination, RENEW was an incomplete experiment; however, the results were consistent with observations from earlier phase studies. These findings underscore the need for a definitive trial. (Efficacy and Safety of Targeted Intramyocardial Delivery of Auto CD34 + Stem Cells for Improving Exercise Capacity in Subjects With Refractory Angina [RENEW]: NCT01508910)

Objectives: This study sought to assess the pharmacodynamic (PD) effects of switching to ticagrelor patients who were treated with prasugrel after undergoing percutaneous coronary intervent...

Background Platelet inhibitory effects induced by oral P2Y 12 receptor antagonists are delayed in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI), which may be attributed to impaired absorption affecting drug pharmacokinetics (PK) and pharmacodynamics (PD). Crushing tablets has been suggested to lead to more favorable PK/PD profiles. To date, no studies have investigated the PK/PD effects of crushing prasugrel. Objectives This study sought to determine whether crushing prasugrel is associated with more favorable drug bioavailability and platelet inhibitory effects compared with whole tablets in STEMI patients undergoing PPCI. Methods Our prospective, randomized, open-label study assessed STEMI patients undergoing PPCI (n = 52) who were treated with a prasugrel 60-mg loading dose (LD) either as whole or crushed tablets. PK/PD analyses were performed at 7 time points. PD effects were measured as P2Y 12 reaction units and platelet reactivity index, and PK by plasma levels of prasugrel’s active metabolite. Results Compared with whole tablets, crushed prasugrel led to reduced P2Y 12 reaction units by 30 min post-LD, which persisted at 1, 2 (164 vs. 95; least square mean difference = 68; 95% confidence interval: 10 to 126; primary endpoint), and 4 h post-LD. Significant differences were no longer present at 6 h post-LD. Parallel findings were shown with platelet reactivity index. Accordingly, high on-treatment platelet reactivity rates were reduced with crushed prasugrel. PK analyses showed a >3-fold faster absorption with crushed compared with whole prasugrel. Conclusions In STEMI patients undergoing PPCI, crushed prasugrel leads to faster drug absorption, and consequently, more prompt and potent antiplatelet effects compared with whole tablet ingestion. (Pharmacological Effects of Crushing Prasugrel in STEMI Patients; NCT02212028 )

Opposing Viewpoint, see p 1382 > “ T o a man with a hammer, the world looks like a nail.” > > —Mark Twain The continuing evolution of new technologies has resulted in a noted improvement in procedural outcomes in patients undergoing percutaneous coronary interventions (PCI) for chronic total occlusions (CTO). We now have an expansive selection of interventional tools and techniques to successfully perform these complex interventional procedures. Coronary guide wires specifically engineered to facilitate crossing almost any CTO lesion are now available. We have developed plaque modification tools, devices facilitating directed subintimal tracking and reentry, and retrograde CTO techniques resulting in previously unimagined procedural success rates approaching >80% in the hands of experienced operators. These tools have allowed us to expand the group of patients that we now consider approachable, although CTO PCI currently represent only 3% to 4% of all PCI procedures performed in the United States.1 Similarly, procedural complication rates continue to decline, although other factors such as radiation exposure, contrast volume, and the increased use of costly resources remain problematic. Overall, these observations underscore the need for the cardiac interventional community to more objectively understand the risks and benefits of CTO PCI. Although a possible mortality benefit for most patient populations undergoing PCI has been extensively investigated, a clear mortality benefit has only been clearly demonstrated in patients presenting with acute coronary syndromes, …

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

Objectives The goal of this study was to assess the pharmacokinetic (PK) and pharmacodynamic (PD) profiles of escalating ticagrelor loading dose (LD) regimens in primary percutaneous coronary intervention (PPCI). Background Patients with ST-segment elevation myocardial infarction undergoing PPCI frequently have suboptimal platelet inhibition in the early hours after ticagrelor LD. The use of high ticagrelor LD regimens has been hypothesized to optimize platelet inhibition in PPCI. Methods This was a prospective, randomized study of escalating ticagrelor LD regimens (180 mg, 270 mg, or 360 mg) in PPCI (N = 52). PK/PD analyses were performed before and 30 min, 1, 2, 4, 8, and 24 h post-LD. PK assessments included exposure to ticagrelor and its metabolite (AR-C124910XX). PD assessments included P2Y12 reaction units (PRU) measured by VerifyNow P2Y12 and platelet reactivity index (PRI) measured by vasodilator-stimulated phosphoprotein (VASP). Results Platelet reactivity was elevated during the first 2 h post-LD. There were no differences in PRU between groups during the study time course (p = 0.179). There were no significant differences in PRU levels across groups at all time points, except at 1 h (p = 0.017) where platelet reactivity was lowest with a 270-mg LD. No differences were found between the 180-mg and 360-mg groups (primary endpoint; p > 0.999). High on-treatment platelet reactivity rates were not different across groups, except at 1 hour (p = 0.038). Parallel PD findings were observed with VASP-PRI. PK analysis showed a delay in ticagrelor absorption and generation of AR-C124910XX, irrespective of dose. Although morphine was associated with a delay in ticagrelor PK/PD, it was not an independent predictor of high on-treatment platelet reactivity. Conclusions ST-segment elevation myocardial infarction patients undergoing PPCI frequently exhibit impaired response to ticagrelor in the early hours after drug administration, which cannot be overcome by increasing LD regimens. These PD findings are largely attributed to an impaired PK profile, indicating a delay in drug absorption compared with that reported in stable clinical settings. (High Ticagrelor Loading Dose in STEMI; NCT01898442)

Since its development >15 years ago, transcatheter aortic valve replacement (TAVR) has rapidly evolved and is now a well-established treatment option for patients with severe symptomatic aortic stenosis at increased risk for surgical aortic valve replacement (SAVR). In patients with a prohibitive risk for open-heart surgery, TAVR reduced the 1- and 2-year all-cause mortality by almost half compared with standard medical therapy.1 TAVR with a balloon-expandable prosthesis in high-risk patients achieved similar 5-year rates of cardiovascular outcomes and mortality compared with SAVR.2 At 3 years, TAVR with a self-expanding prosthesis reduced the incidence of stroke and provided similar survival outcomes compared with surgery in high-risk patients.3 Most recently, TAVR achieved almost identical rates of the composite of all-cause death and disabling stroke compared with surgery for patients at intermediate surgical risk.4,5 Consequently, guidelines now include TAVR as a treatment option for extreme-, high-, and intermediate-risk patients with severe symptomatic aortic stenosis.6 The number of patients treated with commercial TAVR in the United States has nearly doubled from >26 000 in 20147 to >50 000 in 2016 and has already reached >300 000 treated patients worldwide. However, several challenges need to be resolved for TAVR to become the mainstream treatment for patients with aortic stenosis. TAVR is currently being examined as a therapeutic option for low-risk patients in 2 large multicenter randomized controlled trials (PARTNER [The Placement of Aortic Transcatheter Valve Trial] III and The CoreValve low-risk trial). Preliminary signals from the NOTION (Nordic Aortic Valve Intervention) trial are encouraging finding no significant difference in the 30-day and the 1-year rates of stroke and all-cause mortality in low-risk patients randomized to SAVR or TAVR with the CoreValve self-expanding prosthesis.8 These reported outcomes are similar to those of low-risk patients who underwent SAVR in a contemporary …

Background Several studies have shown that patients with diabetes mellitus (DM) exhibit an impaired response to clopidogrel. This may contribute to their increased risk of recurrent atherothrombotic events, despite the use of dual-antiplatelet therapy. The mechanisms for impaired clopidogrel response in DM patients have not been fully elucidated. Objectives The aim of this study was to explore the mechanisms for impaired clopidogrel-mediated platelet inhibition in patients with DM using a comprehensive methodological approach embracing both pharmacokinetic (PK) and pharmacodynamic (PD) assessments as well as ex vivo and in vitro investigations. Methods Patients (DM, n = 30; non-DM, n = 30) with stable coronary artery disease taking aspirin 81 mg/day and P2Y12 antagonist naive were enrolled. Blood was collected before and at various times (0.5, 1, 2, 4, 6, and 24 h) after a 600-mg loading dose of clopidogrel. PD assessments included vasodilator-stimulated phosphoprotein, light transmission aggregometry, and VerifyNow P2Y12 ex vivo, before and after dosing and following in vitro incubation with escalating concentrations (1, 3, and 10 μM) of clopidogrel's active metabolite (Clop-AM). Exposure to Clop-AM was also determined. Results PD assessments consistently showed that during the overall 24-h study time course, residual platelet reactivity was higher in DM patients compared with non-DM patients. In vitro incubation with Clop-AM revealed altered functional status of the P2Y12 signaling pathway in DM platelets as measured by vasodilator-stimulated phosphoprotein, but not with other PD assays. Clop-AM exposure was ∼40% lower in DM patients than in non-DM patients. Conclusions The present study suggests that among DM patients, impaired P2Y12 inhibition mediated by clopidogrel is largely attributable to attenuation of clopidogrel's PK profile. This is characterized by lower plasma levels of Clop-AM over the sampling time course in DM patients compared with non-DM patients and only modestly attributed to altered functional status of the P2Y12 signaling pathway.

Smokers have a greater relative benefit of clopidogrel therapy compared with nonsmokers, likely attributed to its enhanced pharmacodynamic (PD) effects. However, to date, all PD studies have been conducted in patients on dual antiplatelet therapy with aspirin and clopidogrel, and it is unknown whether clopidogrel monotherapy can offer more effective antithrombotic effects compared with aspirin alone among smoking patients. Sixty aspirin-treated (81 mg/day) patients with vascular disease, classified as nonsmokers, light smokers, and heavy smokers according to cotinine serum levels, were enrolled. Patients were switched to clopidogrel (75 mg/day) monotherapy for 7-10 days. PD assessments were performed before and after switch by multiple electrode aggregometry (MEA) and kaolin-activated thromboelastography (TEG). Complete PD data were obtained in 57 patients (nonsmokers, n = 27; light smokers, n = 13; heavy smokers, n = 17). On treatment platelet reactivity following MEA, adenosine diphosphate (ADP) + prostaglandin E1 (PGE1) and thrombin receptor-activating peptide (TRAP) stimuli were significantly lower among heavy smokers following switch to clopidogrel. A significant inverse effect was observed with MEA arachidonic acid (ASPI), while neutral findings were shown with MEA collagen (COLL) stimulus. Thrombin and fibrin activity assessed by clot generation parameters were all nonsignificantly different but showed trends towards enhanced antithrombotic activity with clopidogrel among heavy smokers. In heavy smokers with vascular disease manifestations, clopidogrel is associated with enhanced platelet inhibitory effects, affecting purinergic and non-purinergic pathways, compared with aspirin as measured by MEA. Moreover, among smokers, clopidogrel offers trends towards enhanced effects on parameters of clot generation measured by TEG.

Granting clinical staff privileges to physicians is the primary mechanism institutions use to uphold quality care. The Joint Commission requires that medical staff privileges be based on professional criteria specified in medical staff bylaws. Physicians themselves are charged with defining the

SummaryDifferent aspirin dosing regimens have been suggested to impact outcomes when used in combination with adenosine diphosphate (ADP) P2Y12 receptor antagonists. Prior investigations have shown that not only aspirin, but also potent ADP P2Y12 receptor blockade can inhibit thromboxane A2-mediated platelet activation. The impact of aspirin dosing on ADP mediated platelet activities is unknown and represents the aim of this in vitro pilot pharmacodynamic (PD) investigation. Twenty-six patients with stable coronary artery disease on aspirin 81 mg/day and P2Y12 naïve were enrolled. PD assessments were performed at baseline, while patients were on 81 mg/day aspirin and after switching to 325 mg/day for 7 ± 2 days with and without escalating concentrations (vehicle, 1, 3, and 10 μM) of prasugrel’s active metabolite (P-AM). PD assays included flow cytometric assessment of VASP to define the platelet reactivity index (PRI) and the Multiplate Analyzer (MEA) using multiple agonists [ADP, ADP + prostaglandin (PGE1), arachidonic acid (AA), and collagen]. Escalating P-AM concentrations showed incremental platelet P2Y12 inhibition measured by VASP-PRI (p

Current guidelines on revascularization for unprotected left main coronary artery (ULMCA) disease largely rely on the SYNTAX (Synergy Between PCI With Taxus and Cardiac Surgery) score, an angiographic scoring system that assigns integer points based on anatomic considerations and lesion complexity.1,2 Historically, both the American College of Cardiology/American Heart Association and European Society of Cardiology cardiovascular practice guidelines have determined that coronary artery bypass grafting (CABG) is the reference treatment standard for ULMCA revascularization, independent of individual anatomic SYNTAX score. As experience and data have evolved, there is currently a gradient of recommendations for percutaneous coronary intervention (PCI) as an alternative to CABG in patients presenting with high surgical risk and low or intermediate SYNTAX scores, with recommendations that slightly differ on the 2 sides of the Atlantic.1,2 Both sets of guidelines agree that CABG is the preferred revascularization strategy for patients with a high SYNTAX score (>32), which typically reflects the presence of extensive multivessel disease (downstream from the ULMCA). However, current guidelines do not clearly address a considerable group of patients who may experience positive outcomes with either CABG or PCI. A recent patient-level analysis of SYNTAX and PRECOMBAT (Premier of Randomized Comparison of Bypass Surgery Versus Angioplasty Using Sirolimus-Eluting Stent in Patients With Left Main Coronary Artery Disease), the 2 pivotal ULMCA revascularization trials conducted during the era of first-generation drug-eluting stents, reached …

Several platelet function tests (PFT) are available to assess the pharmacodynamic (PD) effects of P2Y

Background: Patients with diabetes mellitus (DM) are at increased risk of atherothrombotic events, underscoring the importance of effective platelet inhibiting therapies. Prasugrel and ticagrelor reduce thrombotic complications to a greater extent than clopidogrel. Subgroup analyses of pivotal clinical trials testing prasugrel and ticagrelor versus clopidogrel showed DM patients to have benefits that were consistent with the overall trial populations, although the magnitude of the ischemic risk reduction appeared to be enhanced with prasugrel. Whether these findings may be attributed to differences in the pharmacodynamic profiles of these drugs in DM patients remains poorly explored and represented the aim of this study. Methods: In this prospective, randomized, double-blind, double-dummy, crossover pharmacodynamic study, aspirin-treated DM patients (n=50) with coronary artery disease were randomly assigned to receive prasugrel (60 mg loading dose [LD]/10 mg maintenance dose once daily) or ticagrelor (180 mg LD/90 mg maintenance dose twice daily) for 1 week. Pharmacodynamic assessments were conducted using 4 different assays, including VerifyNow P2Y12, vasodilator-stimulated phosphoprotein, light transmittance aggregometry, and Multiplate, which allowed us to explore ADP- and non–ADP-induced (arachidonic acid-, collagen-, thrombin receptor-activating, peptide-induced) platelet signaling pathways. The acute (baseline, 30 minutes, and 2 hours post-LD) and maintenance (1 week) effects of therapy were assessed. The primary end point of the study was the comparison of P2Y 12 reaction units determined by VerifyNow P2Y12 at 1 week between prasugrel and ticagrelor. Results: ADP- and non–ADP-induced measures of platelet reactivity reduced significantly with both prasugrel and ticagrelor LD and maintenance dose. P2Y 12 reaction units defined by VerifyNow were similar between prasugrel and ticagrelor at 30 minutes and 2 hours post-LD. At 1 week, P2Y 12 reaction units were significantly lower with ticagrelor than with prasugrel (52 [32–72] versus 83 [63–103]; least-square means difference: –31; 95% confidence interval, –57 to –4; P =0.022; primary end point). Pharmacodynamic assessments measured by vasodilator-stimulated phosphoprotein, light transmittance aggregometry, and Multiplate were similar between prasugrel and ticagrelor at each time point, including at 1 week. Rates of high on-treatment platelet reactivity were similar between groups with all assays at all time points. Conclusions: In DM patients with coronary artery disease, ticagrelor exerts similar or greater inhibition of ADP-induced platelet reactivity in comparison with prasugrel in the acute and chronic phases of treatment, whereas the inhibition of measures of non–ADP-induced platelet reactivity was not significantly different between the 2 agents. Clinical Trial Registration: URL: http://www.clinicaltrials.gov . Unique identifier: NCT01852214.

Objectives To report a series of consecutive patients that developed retroperitoneal hemorrhage (RPH) and persistent hypotension treated with endovascular approach. Background RPH is a rare complication of percutaneous cardiovascular interventions associated with high morbidity and mortality. The standard approach to treat this complication has been a conservative management for stable patients, and urgent vascular surgery for those with persistent hypovolemic shock. Percutaneous endovascular treatment has evolved as an alternative treatment option. Methods We implemented a management algorithm for patients with suspected RPH and persistent hypotension which embraced systematic use of emergency endovascular evaluation and treatment following clinical assessment without the use of non-invasive diagnostic testing. We report a series of 8 consecutive patients that developed RPH with persistent hypotension. Results Successful percutaneous treatment was achieved in all cases with the use of a covered stent. No patient required vascular surgery. The average blood transfusion was 3.4 ± 2.7 units per patient. There were no deaths; one patient experienced acute stent thrombosis that was successfully treated via endovascular approach. At 1-year follow-up, no further events were reported. Conclusion The incorporation of a standardized protocol using only clinical evaluation followed by emergency percutaneous approach without delays attributed to non-invasive diagnostic work-up showed to be feasible and associated with favorable outcomes. © 2016 Wiley Periodicals, Inc.

This study sought to assess the pharmacodynamic (PD) effects of switching to ticagrelor patients who were treated with prasugrel after undergoing percutaneous coronary intervention in the setting of an acute coronary syndrome.In clinical practice, there is a frequent need to switch between P2Y12 receptor inhibitors. However, concerns on drug interactions have emerged when switching therapies. To date, the PD effects of switching from prasugrel to ticagrelor have yet to be investigated.This was a prospective, randomized, open-label, 3-arm, parallel-design study conducted in patients (n = 82) on maintenance dual antiplatelet therapy with aspirin (81 mg QD) and prasugrel (10 mg QD). Patients were randomized to continue prasugrel 10 mg QD or switch to ticagrelor 90 mg bid, with or without a 180 mg loading dose (LD), for 1 week. PD assessments included P2Y12 reaction units (PRU) by VerifyNow, platelet reactivity index by vasodilator-stimulated phosphoprotein (VASP), and platelet aggregation by light transmittance aggregometry (LTA) at a total of 6 time points: baseline, 2 h, 4 h, 24 h, 48 h, and 1 week after randomization.After switching to ticagrelor, PRU levels decreased as early as 2 h after drug administration. Mean PRU levels remained low during the study time course, without evidence of drug interactions. The primary endpoint of noninferiority of ticagrelor (2 arms combined) versus prasugrel measured by PRU at 1 week was met (least squares mean difference: -18; 95% confidence interval: -41 to 5). There was no increase in rates of high on-treatment platelet reactivity (PRU208), which were overall very low throughout the study time course. Similar levels of platelet reactivity were observed irrespective of the use of a ticagrelor LD. Parallel findings were observed with VASP and LTA.Switching from prasugrel to ticagrelor leads to transiently higher levels of platelet inhibition, irrespective of the use of a LD, without evidence of drug interactions. (Pharmacodynamic Evaluation of Switching From Prasugrel to Ticagrelor [SWAP3]; NCT02016170).

Diabetes mellitus (DM) is the most important predictor of chronic kidney disease (CKD), and pharmacodynamic (PD) studies have shown that DM patients with impaired renal function are characterized by reduced clopidogrel response. However, post-hoc PD studies conducted in unselected cohorts, composed of both DM and non-DM patients, have reached controversial findings on the effects of CKD on clopidogrel response, likely attributed to patient heterogeneity. The impact of renal function on clopidogrel response in non-DM patients remains unexplored and represented the aim of this prospective investigation. We conducted a prospective PD investigation in non-DM patients with and without CKD defined as an estimated glomerular filtration rate (eGFR) below or above 60 mL/min, respectively. All patients had known coronary artery disease and were on maintenance aspirin therapy. PD assessments were assessed at baseline and 2 and 24 h after a 600 mg loading dose of clopidogrel. PD assays included light transmission aggregometry (LTA) using 5 and 20 μmol ADP with and without PGE1 and flow cytometric assessment of the phosphorylation status of the vasodilator-stimulated phosphoprotein (VASP) to determine the platelet reactivity index. A total of 60 patients were studied (n = 30 eGFR ≥60 mL/min; n = 30 eGFR

Physician competence is perhaps the most essential part of the many complex components involved in providing optimal heath care. The patient’s trust that their physicians have the appropriate training, fund of knowledge, clinical decision-making, and technical skills to deliver their healthcare services in a caring manner, with the ultimate goal of providing the safest and most efficacious clinical results, is fundamental to the patient–doctor relationship. Healthcare systems and payers also expect optimal care delivered in an efficient and cost-sensitive manner. The only groups with the knowledge and background required to define and evaluate physician competence on a sustained basis are the physicians themselves. The United States has historically been a leader in training clinicians and setting quality standards for healthcare delivery. This has been especially evident in the field of interventional cardiology, a relatively young subspecialty with a history of robust evolution and expansion since the early days of Andreas Gruentzig’s pioneering first coronary balloon angioplasty in 1977. During the past 35 years, the field has rapidly and relentlessly expanded. We are a field that started with a rather simple balloon-based revascularization concept only applicable to a limited number of carefully chosen patients. We have now evolved into an expansive subspecialty treating a wide range of both stable and acutely ill patients presenting with a broad spectrum of not only increasingly complex coronary artery disease, but also other cardiovascular conditions. Notably, during the past decade, further expansion into the areas of peripheral vascular and structural heart disease has occurred.1 This has been accompanied by the proliferation of a voluminous amount of scientific information facilitating our interventional community’s maturation. We have assumed a leadership position in the practice of evidence-based clinical medicine. However, the ever-emerging advances in our field have inevitably led us to another critical challenge in the optimal …

Objectives The purpose of this study is to assess the pharmacodynamic effects of different prasugrel dosing regimens in patients on maintenance prasugrel therapy. Background There are a growing number of patients on chronic prasugrel therapy regimens, leading to questions about the dosing regimen of prasugrel to administer if percutaneous coronary intervention is required. Methods This is a prospective pharmacodynamic study in patients (n = 64) receiving maintenance prasugrel therapy who were randomly allocated to a 10 mg, 30 mg, or 60 mg dose of prasugrel. Pharmacodynamic assessments using multiple assays were conducted at 3 timepoints (baseline and 1 h and 4 h after dosing). Results Intragroup comparisons showed that a 60 mg dose reduced the platelet reactivity index (PRI) after 1 h (p = 0.004) and 4 h (p Conclusions For patients on maintenance prasugrel therapy, a 60 mg dosing strategy is associated with faster and higher platelet inhibition compared with lower doses, as assessed by P2Y12 specific assays. (Impact of Prasugrel Re-load on Platelet Aggregation in Patients on Chronic Prasugrel Therapy; NCT01201772)

Objectives This study sought to assess the presence of a dose-response effect of cigarette smoking and its impact on high on-treatment platelet reactivity (HPR) in patients with diabetes mellitus treated with clopidogrel. Background Cigarette smoking is an inducer of cytochrome P450 1A2, a hepatic enzyme involved in clopidogrel metabolism. If cigarette smoking is associated with a dose-response effect on pharmacodynamic measures in clopidogrel-treated patients is unknown. Methods A total of 134 type 2 diabetes mellitus patients on maintenance aspirin and clopidogrel therapy were studied. Patients were divided into 3 groups according to cotinine levels: Results A dose-response effect was observed for all pharmacodynamic parameters tested. Serum cotinine levels were inversely associated with platelet reactivity as assessed by light transmittance aggregometry using 5 and 20 μmol/l adenosine diphosphate (p Conclusions Cigarette smoking is associated with a dose-response effect on clopidogrel-induced antiplatelet effects and lower rates of HPR in diabetes mellitus patients.

SummaryPatients with type 2 diabetes mellitus (T2DM) have impaired clopidogrel-induced antiplatelet effects, which may be in part attributed to their reduced sensitivity to insulin and consequently, results in upregulation of the P2Y12 signalling pathway. It has been hypothesised that insulin sensitising strategies may enhance clopidogrel-mediated P2Y12 inhibitory effects. The aim of this pilot pharmacodynamics (PD) study was to assess the impact of pioglitazone on clopidogrel-mediated P2Y12 inhibitory effects in patients with T2DM. This was a prospective, randomised, double-blind, placebo-controlled, cross-over PD study. Patients with T2DM and stable coronary artery disease on maintenance aspirin and clopidogrel were randomised to receive either pioglitazone 30 mg or matching placebo daily for 14 days. PD assessments were measured at baseline, 14 days after randomisation, at the end of the wash-out period, and 14 days after cross-over. The primary endpoint measure was maximal platelet aggregation (MPA) to 20 μM adenosine diphosphate (ADP) as assessed by light transmittance aggregometry (LTA). Flow cytometric analysis of vasodilator-stimulated phosphoprotein phosphorylation (VASP-PRI), and VerifyNow P2Y12 testing were also performed. A total of 15 randomised patients completed the study. MPA to 20 μM ADP (primary endpoint) was not significantly different with pioglitazone compared with placebo (49.53 ± 4.76 vs. 52.52 ± 3.89%; p = 0.594). Similarly, other PD measures did not differ significantly between the groups. In conclusion, in patients with T2DM on maintenance aspirin and clopidogrel therapy, the adjunctive use of pioglitazone does not result in enhanced inhibition of platelet P2Y12 mediated signalling.

A 70-year-old Caucasian man with a history of coronary artery disease (CAD) 9 months status post–2-vessel coronary artery bypass grafting (left internal mammary artery to left anterior descending artery and saphenous vein graft to the first oblique marginal artery) performed at an outside hospital

In high-risk acute coronary syndrome patients undergoing percutaneous coronary intervention, the pharmacodynamic (PD) effects of ticagrelor and prasugrel are subject to variability in response profiles in the early hours after drug administration [(1)][1]. In particular, 2 to 4 h may be required

Objectives The purpose of this study was to determine the safety and efficacy of percutaneous coronary intervention (PCI) compared with coronary artery bypass graft (CABG) in patients with left main coronary artery (LMCA) disease. Background Previous meta-analyses of PCI versus CABG in LMCA disease mainly included nonprospective, observational studies. Several new randomized trials have recently been reported. Methods We identified 1,611 patients from 4 randomized clinical trials for the present meta-analysis. The primary endpoint was the 1-year incidence of major adverse cardiac and cerebrovascular events (MACCE), defined as death, myocardial infarction (MI), target vessel revascularization (TVR), or stroke. Results PCI was associated with a nonsignificantly higher 1-year rate of MACCE compared with CABG (14.5% vs. 11.8%; odds ratio [OR]: 1.28; 95% confidence interval [CI]: 0.95 to 1.72; p = 0.11), driven by increased TVR (11.4% vs. 5.4%; OR: 2.25; 95% CI: 1.54 to 3.29; p Conclusions In patients with LMCA disease, PCI was associated with nonsignificantly different 1-year rates of MACCE, death, and MI, a lower risk of stroke, and a higher risk of TVR compared with CABG.

Introduction and objectives: One of the aims of secondary prevention is to achieve plaque stabilization. This study sought to investigate the clinical consequences and predictive factors of the change in the type of plaque (CTP) as assessed by serial intracoronary ultrasound in type II diabetic patients with known coronary artery disease. Methods: 237 segments (45 patients) from the DIABETES I, II, and III trials were included. Intracoronary ultrasound from motorized pullbacks (0.5 mm/s) after index procedure and at 9-month angiographic follow-up was performed in the same coronary segment. Nontreated mild lesions (angiographic stenosis < 25%) with 0.5 mm plaque thickening and 5 mm of length assessed by intracoronary ultrasound were included. As different types of plaques may be encountered throughout a given coronary lesion, each study lesion was divided into 3 segments for serial quantitative and qualitative analyses. Statistical adjustment by multiple lesion segments per patient (generalized estimating equations method) was performed. A CTP was defined as any qualitative change in plaque type at followup. At 1-year follow-up, major adverse cardiac events – death, myocardial infarction and target vessel revascularization) – were recorded. Results: A CTP was observed in 48 lesions (20.2%) and occurred more frequently (52.1%) in mixed plaques. Independent predictors of CTP were glycated hemoglobin levels (odds ratio [OR] 1.2; 95% confidence interval [CI] 1.01-1.5; P = .04); glycoprotein IIb-IIIa inhibitors (OR 0.3; 95% CI 0.1-0.7; P = .004) and statin administration (OR 0.3; 95% CI 0.1-0.8; P = .02). At 1-year follow-up CTP was associated with an increase in major adverse cardiac events rate (CTP 20.8% vs non-CTP 13.8%, P = .008; hazard ratio = 1.9, 95% CI 1.3-1.9, P = .01). Conclusions: Qualitative changes in mild stenosis documented by intracoronary ultrasound in type II diabetics are associated with suboptimal secondary prevention and may have clinical consequences.

Introduction and objectives: One of the aims of secondary prevention is to achieve plaque stabilization. This study sought to investigate the clinical consequences and predictive factors of the change in the type of plaque (CTP) as assessed by serial intracoronary ultrasound in type II diabetic patients with known coronary artery disease. Methods: 237 segments (45 patients) from the DIABETES I, II, and III trials were included. Intracoronary ultrasound from motorized pullbacks (0.5 mm/s) after index procedure and at 9-month angiographic follow-up was performed in the same coronary segment. Nontreated mild lesions (angiographic stenosis