Platelet function monitoring for stent thrombosis in critically III patients with an acute Coronary syndrome

Optimal Antithrombotic Strategies in Cardiogenic Shock

Cardiogenic shock (CS) represents a critical condition with a high mortality rate. The most common cause of CS is coronary artery disease, and patients typically present with myocardial infarction, necessitating immediate treatment through percutaneous coronary intervention (PCI) and often requiring mechanical circulatory support. CS is associated with a prothrombotic situation, while on the other hand, there is often a significant risk of bleeding. This dual challenge complicates the selection of an optimal antithrombotic strategy. The choice of antithrombotic agents must be personalized, taking into consideration all relevant conditions. Repeated risk assessment, therapeutic monitoring, and adjusting antithrombotic therapy are mandatory in these patients. This review article aims to provide an overview of the current evidence and practical guidance on antithrombotic strategies in the context of CS.

Balancing thrombosis and bleeding after out-of-hospital cardiac arrest related to acute coronary syndrome: A literature review

Balance between thrombosis and bleeding is now well recognized in patients treated for acute coronary syndrome, with impact on short- and long-term prognosis, including survival. Recent data suggest that patients who are resuscitated after out-of-hospital cardiac arrest related to myocardial infarction are at an even higher risk of bleeding and thrombosis than those with uncomplicated acute coronary syndrome. Delayed enteral absorption of medication due to induced hypothermia and systemic inflammation increases thrombosis risk, whereas transfemoral access site, cardiopulmonary resuscitation manoeuvres and mechanical circulatory support devices increase bleeding risk. In addition, post-resuscitation syndrome and renal or hepatic impairment are potential risk factors for both bleeding and thrombotic complications. There are currently no randomized controlled trials comparing various P₂Y₁₂ inhibitor and/or anticoagulation strategies in the setting of out-of-hospital cardiac arrest, and current practice is largely derived from management of patients with uncomplicated acute coronary syndrome. The aim of this review is therefore to describe the bleeding and thrombosis risk factors in this specific population, and to review recent data on antithrombotic drugs in this patient subset.

Response to antiplatelet therapy in patients undergoing invasive treatment due to acute coronary syndrome complicated by cardiogenic shock

Introduction

There are limited data on platelet reactivity and response to antiplatelet drugs in patients with cardiogenic shock.

Aim

To assess platelet reactivity on dual antiplatelet therapy with acetylsalicylic acid (ASA) and ticagrelor, a novel potent P2Y12 receptor inhibitor, in patients with cardiogenic shock in the course of acute coronary syndrome (ACS) who received invasive treatment.

Material and methods

We enrolled 12 consecutive patients with ACS complicated by cardiogenic shock. To assess response to antiplatelet therapy during cardiogenic shock, only patients with symptoms persisting for at least 3 days and who completed a 5-day follow-up were included in the study. Patients received a loading dose of ASA (300 mg) and ticagrelor (180 mg), followed by a maintenance dose (ASA, 1 × 75 mg; ticagrelor, 2 × 90 mg). Blood samples for platelet function tests were collected. Platelet aggregation was assessed with a Multiplate whole-blood impedance aggregometer. Arachidonic acid (AA), adenosine diphosphate (ADP), and thrombin receptor-activating peptide (TRAP) were used as aggregation agonists.

Results

Response to antiplatelet therapy assessed by aggregometry showed numerically higher on-ASA platelet reactivity on day one and statistically significant higher on-ticagrelor platelet reactivity on day one in comparison with following days. There were 2 patients with high on ASA platelet reactivity and 3 with high on ticagrelor platelet reactivity, but only on the day one.

Conclusions

Some patients with cardiogenic shock in the course of ACS treated invasively show a lower response to ASA and ticagrelor only on the first day after invasive treatment, with a good response on subsequent days.

Antithrombotic therapy in patients with acute coronary syndrome complicated by cardiogenic shock or out-of-hospital cardiac arrest: a joint position paper from the European Society of Cardiology (ESC) Working Group on Thrombosis, in association with the Acute Cardiovascular Care Association (ACCA) and European Association of Percutaneous Cardiovascular Interventions (EAPCI)

Timely and effective antithrombotic therapy is critical to improving outcome, including survival, in patients with acute coronary syndrome (ACS). Achieving effective platelet inhibition and anticoagulation, with minimal risk, is particularly important in high-risk ACS patients, especially those with cardiogenic shock (CS) or those successfully resuscitated following out-of-hospital cardiac arrest (OHCA), who have a 30-50% risk of death or a recurrent ischaemic event over the subsequent 30 days. There are unique challenges to achieving effective and safe antithrombotic treatment in this cohort of patients that are not encountered in most other ACS patients. This position paper focuses on patients presenting with CS or immediately post-OHCA, of presumed ischaemic aetiology, and examines issues related to thrombosis and bleeding risk. Both the physical and pharmacological impacts of CS, namely impaired drug absorption, metabolism, altered distribution and/or excretion, associated multiorgan failure, co-morbidities and co-administered treatments such as opiates, targeted temperature management, renal replacement therapy and circulatory or left ventricular assist devices, can have major impact on the effectiveness and safety of antithrombotic drugs. Careful attention to the choice of antithrombotic agent(s), route of administration, drug-drug interactions, therapeutic drug monitoring and factors that affect drug efficacy and safety, may reduce the risk of sub- or supra-therapeutic dosing and associated adverse events. This paper provides expert opinion, based on best available evidence, and consensus statements on optimising antithrombotic therapy in these very high-risk patients, in whom minimising the risk of thrombosis and bleeding is critical to improving outcome.

Platelet indices and outcome after cardiac arrest

BACKGROUND

Platelet variables, including platelet distribution width (PDW) and mean platelet volume (MPV), have been associated with outcome in critically ill patients. We evaluated these variables in patients after cardiac arrest (CA).

METHODS

All adult CA patients admitted to the intensive care unit (ICU) over an 8-year period (2006-2014) and treated with targeted temperature management were included. We retrieved all data concerning CA characteristics as well as platelet count, PDW and MPV on the first 2 days of admission. Unfavorable 3-month neurological outcome was defined as a cerebral performance category score of 3-5.

RESULTS

We included 384 patients (age 62 [52-75] years; 270/384 male): 231 patients (60%) died within 30-days and 246 patients (64%) had an unfavorable 3-month neurological outcome. On admission, platelet count, PDW and MPV were 87 [126-261] *10³cells/mm³, 17 [16.3-17.3]% and 8.3 [7.6-9.2] μm³, respectively. Platelet count decreased significantly over the first 2 days, whereas PDW and MPV did not change significantly. There were no significant differences between the values on admission or time-courses of platelet count, PDW or MPV between survivors and non-survivors or between patients with unfavorable and favorable neurological outcome.

CONCLUSIONS

In our cohort of post-CA patients, PDW and MPV were not associated with outcome.