Platelet reactivity and cardiovascular events after percutaneous coronary intervention in patients with stable coronary artery disease: the Stent Thrombosis In Belgium (STIB) trial

Time-dependent changes in P2Y12 reaction unit values for predicting the different types of cardiovascular events in patients with ischemic heart disease

Several studies have investigated the association between P2Y12 reaction unit (PRU) value and major adverse cardiovascular events (MACEs) in patients with ischemic heart disease, but there is no well-established consensus on the utility of PRU value. Furthermore, the optimal PRU cut-off value varied with studies. One reason may be that the endpoints and observation periods differed, depending on the study. This study aimed to investigate the optimal cut-off and predictive ability of the PRU value for predicting cardiovascular events, while considering different endpoints and observation periods. We surveyed a total of 338 patients receiving P2Y12 inhibitors and measured PRU during cardiac catheterization. Using time-dependent receiver operating characteristic analysis, we evaluated the cut-off and area under curve (AUC) of the PRU value for two MACEs (MACE ①: composite of death, myocardial infarction, stent thrombosis, and cerebral infarction; MACE ②: composite of MACE ① and target vessel revascularization) at 6, 12, 24 and 36 months after cardiac catheterization. MACE ① occurred in 18 cases and MACE ② in 32 cases. The PRU cut-off values at 6, 12, 24, and 36 months were 257, 238, 217, and 216, respectively, for MACE ① and 250, 238, 209, and 204, respectively, for MACE ②. The AUCs at 6, 12, 24, and 36 months were 0.753, 0.832, 0.718, and 0.717, respectively, for MACE ① and 0.724, 0.722, 0.664, and 0.682, respectively, for MACE ②. The optimal cut-off and predictive ability of PRU values for cardiovascular events varied depending on different endpoints and duration of the observation periods. A relatively high PRU value is effective for short-term event suppression, but a low value is required for long-term event suppression.

Periprocedural Myocardial Injury: Pathophysiology, Prognosis, and Prevention

The definition and clinical implications of myocardial infarction occurring in the setting of percutaneous coronary intervention have been the subject of unresolved controversy. The definitions of periprocedural myocardial infarction (PMI) are many and have evolved over recent years. Additionally, the recent advancement of different imaging modalities has provided useful information on a patients' pre-procedural risk of myocardial infarction. Nonetheless, questions on the benefit of different approaches to prevent PMI and their practical implementation remain open. This review aims to address these questions and to provide a current and contemporary perspective.

Antiplatelet therapy in the primary prevention of cardiovascular disease in patients with chronic obstructive pulmonary disease: a randomised controlled proof-of-concept trial

The APPLE COPD-ICON2 trial is a prospective 2×2 factorial, double-blinded proof-of-concept randomised controlled trial targeting patients with chronic obstructive pulmonary disease (COPD) without prior history of cardiovascular disease. The primary goal of this trial is to investigate if treatment with antiplatelet therapy will produce the predefined cut-off of platelet inhibition measured using the Multiplate test in COPD patients. Eligible patients were randomised to aspirin plus placebo, ticagrelor plus placebo, aspirin plus ticagrelor or placebo only for 6 months. The primary outcome comprises inhibition (binary response) of arachidonic acid- (ASPI test, cut-off <40) and adenosine diphosphate- (ADP test, cut-off <46) induced platelet aggregation at 6 months. 543 patients were screened and 120 patients were recruited with mean age of 67.5 years; 47.5% patients were male. The per-protocol ASPI test response rate to aspirin was 68.3% (95% CI 52.3-80.9%). The per-protocol ADP test response rate to ticagrelaor was 68.8% (95% CI 50.4-82.6%). Platelet response to antiplatelet therapy with aspirin and ticagrelor was not observed in nearly one-third of COPD patients without prior history of cardiovascular disease. These findings support the high pro-thrombotic milieu and the need for further research to determine the effect of antiplatelet/antithrombotic therapy on cardiovascular morbidity and mortality in COPD patients.

A randomized, double-blind, placebo-controlled trial to assess the efficAcy and safety of Trimetazidine in patients with angina pectoris having been treated by percutaneous coronary intervention (ATPCI study): Rationale, design, and baseline characteristics

BACKGROUND

About 30% of angina patients have persisting symptoms despite successful revascularization and antianginal therapy. Moreover, in stable patients, percutaneous coronary intervention (PCI) does not improve survival as compared with medical therapy alone. Trimetazidine, an antianginal agent devoid of hemodynamic effect, may help reducing symptoms and improving outcomes after PCI. The ATPCI study is investigating the efficacy and safety of adding trimetazidine to standard-of-care in angina patients who had a recent PCI.

METHODS

ATPCI is a randomized, double-blind, parallel-group, placebo-controlled, event-driven study in patients with coronary artery disease having undergone PCI because of stable angina (elective PCI) or unstable angina/NSTEMI (urgent PCI). After PCI, patients were randomized to trimetazidine (35 mg bid) or placebo on top of standard-of-care including event prevention drugs and antianginal treatment. Patients will be followed for 2 to 4 years. The primary efficacy endpoint is a composite of cardiac death, hospitalization for a cardiac event and recurrence or persistence of angina. Safety events related to trimetazidine use will be monitored.

RESULTS

Recruitment lasted from September 2014 to June 2016. A total of 6007 patients were enrolled (58% and 42% after elective and urgent PCI, respectively). Mean age was 61 years, 77% were males, and median durations of coronary artery disease were 1 and 5 months (if urgent or elective PCI, respectively). Almost all patients received drugs for event prevention and antianginal therapy at baseline.

CONCLUSION

The ATPCI study will shed further light on the management of contemporary angina patients after PCI. Results are expected in 2019.

Antiplatelet agents in uncertain clinical scenarios-a bleeding nightmare

Despite over 40 years since the first percutaneous coronary intervention (PCI) was performed, the optimal dual antiplatelet therapy (DAPT) regime poses a significant challenge for clinicians, especially in certain scenarios. DAPT is the standard of care in PCI following an acute coronary syndrome (ACS) or for elective patients with obstructive coronary artery disease (CAD). There remains significant uncertainty regarding DAPT in patients at high risk of bleeding, such as the elderly and patients requiring anticoagulation. More and more clinicians are faced with a dilemma of weighing risks and benefits from the increasing list of potent, new antiplatelet agents and direct oral anticoagulants (DOACs) in a growing, aging population. Historically, most studies failed to recognize bleeding risk, instead focusing on ischemic risk. In recent years however, bleeding has been recognized as a very significant driver of morbidity and mortality in patients undergoing PCI. There is a paucity of data in this cohort leading to divergent and sometimes conflicting recommendations, largely based on expert consensus of opinion. In the current review, we critically evaluate the available evidence in these uncertain scenarios.

Acute Coronary Stent Thrombosis in Modern Era: Etiology, Treatment, and Prognosis

Acute stent thrombosis (AST) is a rare but life-threatening complication of coronary artery stenting. AST remains a challenging task for cardiologists, despite the application of modern procedural techniques and dual-antiplatelet therapy strategies as well as improved understanding of the underlying pathophysiology. This review focuses on the prevalence, risk factors, prognosis, multiple potential underlying pathogenesis, knowledge gaps, and recommends diagnosis and individualized management strategies of AST.

Independent Predictors of Major Adverse Events following Coronary Stenting over 28 Months of Follow-Up

Background: Despite recent advances in stent design and constantly improving protective pharmacological strategies, complications and adverse events following percutaneous coronary interventions (PCI) are still major factors influencing morbidity and mortality. Therefore, predicting secondary vascular occlusions represents an unmet medical need. Objective: The aim of our study was to triage clinical and laboratory predictors of major adverse clinical events (MACE) following coronary stenting. Methods: This was a prospective, case-controlled, single-center study, which included 94 consecutive patients with documented coronary disease who underwent PCI with drug-eluting stent (DES) implantation. All patients received dual antiplatelet therapy with aspirin and clopidogrel. Numerous clinical characteristics and laboratory biomarkers were assessed before stenting and were correlated with poststenting MACE over the mean follow-up of 28 months. MACE included death, nonfatal myocardial infarction, target vessel revascularisation, stroke, stent thrombosis, angina recurrence and instent restenosis. Results: Twenty-three patients experienced MACE. Independent MACE predictors after PCI with DES implantation were antecedent diabetes mellitus (RR = 0.45; 95% CI 0.20-0.97; p = 0.045), prior thrombolytic therapy (RR = 0.42; 95% CI 0.27-0.83; p = 0.039), baseline plasminogen activator inhibitor -1 (PAI-1; p = 0.008) and plasma von Willebrand factor (vWF) activity (p = 0.007). Other clinical characteristics and laboratory indices showed no correlation with MACE. Conclusions: Background diabetes mellitus, prior thrombolytic therapy, PAI-1 and vWF prestenting activity may be useful for MACE prediction over 28 months of follow-up.

Genetically Determined Platelet Reactivity and Related Clinical Implications

Many drugs are nowadays available to inhibit platelet activation and aggregation, especially in patients with acute coronary syndromes and undergoing percutaneous coronary intervention with stent implantation. Primary targets are represented by enzymes or receptors involved in platelet activation. Genetic mutations in these targets contribute to the inter-individual variability in platelet responses therefore weakening the efficacy of antiplatelet agents. High on treatment platelet reactivity is a condition characterized by low levels of platelet inhibition despite the use of antiplatelet drugs. This could be responsible for re-infarction, stent-thrombosis and strokes, affecting short and long-term prognosis after coronary revascularization. So far, to test antiplatelet resistance either the assessment of platelet function or the identification of genetic carriers of poly morphisms have been pursued. Although several methods are now available to test platelet reactivity, it is still debated whether its routine assessment gives real benefits in clinical practice. The present review aims at examining current evidences on genetic polymorphisms affecting optimal platelet inhibition.