The Clinical Outcomes of Percutaneous Coronary Intervention Performed Without Pre-Procedural Aspirin

Periprocedural Antithrombotic Treatment in Complex Percutaneous Coronary Intervention

ABSTRACT

In recent years, the management of complex lesions in patients undergoing percutaneous coronary intervention (PCI) constitutes a field of high interest and concern for the interventional cardiology. As more and more studies demonstrate the increased hazard of ischemic events in this group of patients, it is of paramount importance for the physicians to choose the optimal periprocedural (pre-PCI, during-PCI and post-PCI) antithrombotic treatment strategies wisely. Evidence regarding the safety and efficacy of current anticoagulation recommendation, the possible beneficial role of the pretreatment with a potent P2Y12 inhibitor in the subgroup of patients with non-ST segment elevation myocardial infarction with complex lesions, and the impact of a more potent P2Y12 inhibitor in individuals with stable coronary artery disease undergoing complex PCI are needed. This will provide and serve as a guide to clinicians to deploy the maximum efficacy of the current choices of antithrombotic therapy, which will lead to an optimal balance between safety and efficacy in this demanding clinical scenario.

Dual Antiplatelet Therapy De-escalation Strategies

Dual antiplatelet therapy (DAPT), the combination of aspirin (ASA), and a P2Y₁₂ inhibitor, protects against stent thrombosis and new atherothrombotic events after a stent implantation or an acute coronary syndrome, but exposes patients to an increased risk of bleeding. In most current practices, the P2Y₁₂ inhibitor is stopped at 6 to 12 months and ASA is continued indefinitely. The advent of safer stents, with less risk of stent thrombosis, has challenged this standard of care, however. A number of alternative strategies involving earlier de-escalation of the antiplatelet therapy have therefore been proposed. In these approaches, standard DAPT is switched to a less potent antithrombotic combination at an earlier time-point than recommended by guidelines. Three different de-escalation variations have been tested to date. The first one maintains DAPT but switches from the potent P2Y₁₂ inhibitors ticagrelor or prasugrel to either a lower dose or to clopidogrel, while maintaining ASA. The 2 other approaches involve changing DAPT to a single antiplatelet at some earlier time-point after the percutaneous coronary intervention procedure, by stopping either the P2Y₁₂ inhibitor or ASA. These strategies have all demonstrated some benefit in clinical trials so far, but especially the contribution of ASA in secondary prevention is clearly evolving as its role in increasing bleeding complications while not providing increased ischemic benefit is becoming more and more clear. In contemporary practice, the type and duration of DAPT should now be based on an individualized decision, and the de-escalation strategies, if used wisely, can be added to the existing options.

Aspirin Hypersensitivity in Patients Undergoing Percutaneous Coronary Intervention. What Should We be Doing?

Aspirin plays a pivotal role in the management of patients with Coronary Artery Disease (CAD) with well-recognised benefits of reducing recurrent myocardial infarction and minimising the risk of stent thrombosis for those undergoing Percutaneous Coronary Intervention (PCI). Dual antiplatelet therapy is mandated for patients undergoing PCI and typically consists of aspirin and a P2Y12 receptor antagonist. Aspirin hypersensitivity poses a significant clinical dilemma, as the safety and efficacy of oral antiplatelet combinations that exclude aspirin have not been validated. Although, genuine hypersensitivity to aspirin is encountered infrequently, it can be challenging when managing patients with concomitant CAD given the paucity of safe and effective alternatives. Aspirin desensitization is a potential and safe option but may not always be practical. This review aims to highlight the challenges of aspirin hypersensitivity in patients undergoing PCI and propose a treatment algorithm to address this issue in clinical practice.

Omitting aspirin in PCI patients: Myth or reality?

In the current era of percutaneous coronary intervention (PCI), with the use of contemporary drug-eluting stents, refined techniques, and adjunctive pharmacotherapy, the role of aspirin peri-PCI remains undisputable. Beyond the initial period, dual antiplatelet therapy (DAPT) consisting of aspirin and a P2Y₁₂ receptor inhibitor for 6 months in stable coronary artery disease and 12 months in acute coronary syndromes is the standard of care. However, concerns regarding bleeding adverse events caused by aspirin have led to shortened DAPT duration or even omission of aspirin. Aspirin free-strategies have been increasingly encountered in several studies and showed a significant reduction in bleeding events, without any sign of increased ischemic risk. Individualization of DAPT duration particularly in high bleeding risk patients appears therefore mandatory, making aspirin not necessary in several cases. Moreover, recent randomized trials have shed light on how to treat PCI patients in the presence of concomitant anticoagulant treatment with P2Y₁₂ monotherapy and excluding aspirin. These aspirin-free strategies have been proved safer than the "older" standard triple antithrombotic treatment, without compromising safety. Ongoing studies may further dispel the myths and establish real facts regarding post-PCI-tailored treatment with or without aspirin.

Rapid Aspirin Desensitization is Safe and Feasible in Patients With Stable and Unstable Coronary Artery Disease: A Single-Center Experience

AIMS

There are limited data on aspirin (ASA) desensitization for patients with coronary disease. We present our experience with a rapid nurse-led oral desensitization regimen in patients with aspirin sensitivity undergoing coronary angiography.

METHODS

This single-center retrospective observational study includes patients with a history of ASA sensitivity undergoing coronary angiography with intent to perform percutaneous coronary intervention (PCI).

RESULTS

Between January 2012 and January 2017, 24 patients undergoing coronary angiography for stable coronary disease (7 cases) or acute coronary syndromes (non-ST-segment myocardial infarction [NSTEMI; 8 cases], STEMI [9 cases]) underwent aspirin desensitization having reported previous reactions to aspirin. At initial presentation, previous sensitivity reactions were reported as: mucocutaneous reactions in 17 patients (urticaria in 3 [13%], nonurticarial rash in 6 [25%], angio-oedema in 8 [33%]), respiratory sensitivity in 4 (17%), and systemic anaphylactoid reactions in 3 (13%). Seventeen (71%) patients underwent PCI. Desensitization was acutely successful in 22 (92%) patients and unsuccessful in 2 (8%) patients who both had a single short-lived episode of acute bronchospasm treated successfully with nebulized salbutamol. Fifteen successfully desensitized patients completed 12 months of aspirin; no patient had recurrent hypersensitivity reaction. Aspirin was stopped prior to 12 months in 7 patients (replaced by warfarin [1 case], no antiplatelet or single antiplatelet clinically indicated and clopidogrel chosen [4 cases], patient choice without evidence of recurrent hypersensitivity [1 case], and death due to cardiogenic shock following STEMI [1 case]).

CONCLUSION

A rapid aspirin desensitization protocol is safe and effective across a broad spectrum of hypersensitivity reactions and clinical presentations.

Cerebrovascular accidents after percutaneous coronary interventions from 2002 to 2014: Incidence, outcomes, and associated variables

BACKGROUND

Cerebrovascular accident (CVA) and transient ischemic attack (TIA) related to percutaneous coronary intervention (PCI) are relatively rare complications, but they are associated with high morbidity and mortality. Given the evolution of both CVA risk and PCI techniques over time, this study was conducted to evaluate trends in CVA and TIA associated with PCI and to identify variables associated with neurologic events.

METHODS

Consecutive patients undergoing PCI at the Washington Hospital Center between January 2002 and June 2015 were included. Prespecified data were prospectively collected, including baseline and procedural characteristics, in-hospital outcomes, and 1-year mortality. The subjects who had a CVA or TIA during or immediately after PCI were compared with those without procedure-associated CVA or TIA.

RESULTS

Overall, 25,626 patients were included in the study. The mean age was 65.0 ± 12.4 years, 16,949 (65.2%) were male, and 7,436 (28.6%) were African American. From 2002 to 2015, 110 neurologic events post-PCI were diagnosed (0.43%); this included 86 CVAs (0.34%) and 24 TIAs (0.09%). The annual rate of postprocedural neurologic events was 0.42% ± 0.12%. There were significant changes in baseline risk factors over time, with increasing age, incidence of insulin-dependent diabetes, and chronic kidney disease. Patients with neurologic events were more often African American (43.6% vs 28.6%, P < .001) with prior history of CVA (24.5% vs 7.8%, P < .001), chronic renal insufficiency (26.6% vs 15.2%, P < .001), and insulin-dependent diabetes (19.1% vs 12.4%, P = .03). Acute myocardial infarction (56% vs 30.4%, P < .001) and cardiogenic shock (20.2% vs 3%, P < .001) were also more common among patients with neurologic events post-PCI. After multivariable adjustment, use of an intraaortic balloon pump was strongly associated with neurologic events (odds ratio [OR] 4.9, 95% CI 2.7-8.8, P < .001), as was prior CVA (OR 2.4, 95% CI 1.4-4.4, P = .002) and African American race (OR 2.4, 95% CI 1.5-3.9, P < .001); there was a borderline association with the use of a thrombus extraction device (OR 1.7, 95% CI 0.9-3.2, P = .09). In-hospital mortality (20.0% vs 1.5%, P < .001) and 1-year mortality (45.0% vs 7.3%, P < .001) were also much higher in patients with neurologic events.

CONCLUSION

Neurologic events post-PCI are associated with markedly worse in-hospital outcomes. The incidence of CVA and TIA post-PCI, however, remained stable over the last 12 years despite an increase in risk factors for CVA.

Absorption kinetics of low-dose chewable aspirin--implications for acute coronary syndromes

BACKGROUND

This study describes the implications of the pharmacokinetics of low-dose chewable aspirin for acute coronary syndromes. Current guidelines recommend the administration of 162-325 mg aspirin chewing tablets for the treatment of acute myocardial infarction. Although aspirin is widely used and a cornerstone in myocardial infarction, there is no information available on the pharmacokinetics of low doses of chewable aspirin.

MATERIALS AND METHODS

This prospective trial assessed the pharmacokinetics of acetylsalicylic acid and its metabolite salicylic acid after intake of 162 mg chewable low-dose aspirin in 35 healthy volunteers. Plasma drug and metabolite levels were analysed using high-performance liquid chromatography, and corresponding pharmacodynamics were determined by impedance aggregometry.

RESULTS

Acetylsalicylic acid was rapidly absorbed with a mean Tmax of 27 ± 8 min. Tmax of salicylic acid was 69 ± 21 min. Mean Cmax was 1·8 ± 0·6 mg/L and 7·6 ± 1·4 for acetylsalicylic acid and salicylic acid, respectively. Arachidonic acid-induced aggregation showed maximum platelet inhibition 30 min after drug ingestion.

CONCLUSIONS

The characterization of the plasma-time profile fills the gap between the lack of data on pharmacokinetics and the pharmacodynamics and the recommendation for using low-dose chewable aspirin for acute coronary syndromes. We describe for the first time that a 162-mg dose of chewable aspirin is rapidly absorbed and achieves plasma concentrations of the active metabolite salicylic acid required to maximally inhibit platelet aggregation. However, a 162-mg dose is truly a minimum, and doubling this dose might be better for patients with myocardial infarction.

Aspirin reload before elective percutaneous coronary intervention: impact on serum thromboxane b2 and myocardial reperfusion indexes

BACKGROUND

Microvascular obstruction seems to predict poor outcome in patients undergoing elective percutaneous coronary intervention (PCI), but the underlying mechanism is still unclear. We analyzed whether serum thromboxane B2, a stable metabolite of thromboxane A2, may be implicated in post-PCI microvascular obstruction.

METHODS AND RESULTS

We enrolled 91 patients (74 males, 66±10 years) on chronic low-dose aspirin therapy (aspirin, 100 mg daily) scheduled for elective PCI and randomly assigned to receive aspirin reload (325 mg orally, n=46) or no reload (control group, n=45) ≥1 hour before elective PCI. Serum levels of thromboxane B2, reperfusion indexes (corrected Thrombolysis In Myocardial Infarction frame count and myocardial blush grade), and serum cardiac troponin I were assessed before and after PCI. Serum thromboxane B2 significantly increased after 120 minutes (P=0.0447) from PCI in control but not in aspirin reload group. After PCI, both groups showed a statistically significant reduction in corrected Thrombolysis In Myocardial Infarction frame count more evident in aspirin reload group (P=0.0023). Moreover, after PCI, 61% of patients allocated to aspirin reload and only 32% of patients allocated to control group reached normal microcirculatory reperfusion (myocardial blush grade=3); patients with myocardial blush grade=3 exhibited lower values of serum thromboxane B2 compared with those with myocardial blush grade <3 (P=0.05). Periprocedural cardiac troponin I significantly increased (F=3.64; P=0.01334) and correlated with serum thromboxane B2 (ρ=0.31; P=0.0413) in control but not in aspirin reload group. In addition, left ventricular ejection fraction significantly increased after PCI only in the aspirin reload group (P=0.0005).

CONCLUSIONS

Aspirin loading dose before elective PCI improves myocardial reperfusion and injury indexes, suggesting a possible role of platelet thromboxane A2 in microvascular occlusion.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT01374698.