Aspirin desensitization in patients undergoing percutaneous coronary intervention: a survey of current practice

Aspirin hypersensitivity: a practical guide for cardiologists

Aspirin has been known for a long time and currently stays as a cornerstone of antithrombotic therapy in cardiovascular disease. In patients with either acute or chronic coronary syndromes undergoing percutaneous coronary intervention aspirin is mandatory in a dual antiplatelet therapy regimen for prevention of stent thrombosis and/or new ischaemic events. Aspirin is also currently a first-option antithrombotic therapy after an aortic prosthetic valve replacement and is occasionally required in addition to oral anticoagulants after implantation of a mechanical valve. Presumed or demonstrated aspirin hypersensitivity is a main clinical problem, limiting the use of a life-saving medication. In the general population, aspirin hypersensitivity has a prevalence of 0.6%-2.5% and has a plethora of clinical presentations, ranging from aspirin-exacerbated respiratory disease to anaphylaxis. Although infrequent, when encountered in clinical practice aspirin hypersensitivity poses for cardiologists a clinical dilemma, which should never be trivialized, avoiding-as much as possible-omission of the drug. We here review the epidemiology of aspirin hypersensitivity, provide an outline of pathophysiological mechanisms and clinical presentations, and review management options, starting from a characterization of true aspirin allergy-in contrast to intolerance-to suggestion of desensitization protocols.

ASA Allergy and Desensitization Protocols in the Management of CAD: A Review of Literature

Acetylsalicylic acid (ASA) hypersensitivity still represents one of the major deals for patients with atherosclerotic cardiovascular disease (ASHD), especially for those requiring percutaneous coronary interventions in the absence of validated alternative options. Despite symptoms after ASA administration being reported in 6-20% of cases, true ASA allergy only represents a minority of the patients, pointing to the importance of challenge tests and potential strategies for tolerance induction. ASA desensitization protocols were proposed several decades ago, with accumulating the literature on their use in patients undergoing PCI either for chronic disease or acute coronary syndromes. Nevertheless, the promising results of the studies and meta-analyses have not been validated so far by the support of large-scale randomized trials or unique indications from guidelines. Therefore, ASA desensitization is still largely unapplied, leaving the management of ASA hypersensitivity to the individualized approach of cardiologists.

The effect of acetylsalicylic acid dosed at bedtime on the anti-aggregation effect in patients with coronary heart disease and arterial hypertension: A randomized, controlled trial

BACKGROUND

Acetylsalicylic acid (ASA) is one of the basic drugs used in the secondary prevention of coronary artery disease (CAD), and in most cases it is taken in the morning in one daily dose. It is suggested that the morning peak of platelet aggregation is responsible for the occurrence of myocardial infarctions and strokes. Hence, the aim of the study was to observe the effect of ASA (morning vs. evening) dosing on the anti-aggregative effect of platelets in patients with CAD and arterial hypertension (AH).

METHODS

The study involved 175 patients with CAD and AH. Patients were randomly assigned to one of two study groups, taking ASA in the morning or in the evening. The patients had two visits, one baseline and another after 3 months from changing the time of ASA dosage. The platelet aggregation was determined using the VerifyNow analyzer.

RESULTS

In the ASA evening group, a significant reduction in platelet aggregation was obtained. In the ASA morning group, a significant difference in response to ASA was observed, depending on sex. In men, the reactivity of platelets decreased, but in women it increased.

CONCLUSIONS

In the group of patients with CAD and AH, bedtime ASA dosing is associated with a significant reduction in platelet aggregation. The response to ASA may differ between sexes. The benefit gained by changing the drug administration from the morning to the evening is greater in women.