Evaluating the efficacy of antiplatelet therapy in spontaneous coronary artery dissection: a scoping review.

Background: Spontaneous coronary artery dissection (SCAD) is a poorly-studied cause of acute coronary syndrome (ACS), particularly in women. SCAD is a rare cause of ACS that can lead to myocardial injury due to SCAD. This review evaluates optimal antiplatelet therapy for SCAD patients. There is no clear consensus regarding the optimum antiplatelet medication regimen and treatment duration for SCAD despite current American Heart Association (AHA) consensus guidelines recommending 12-month regimen of dual antiplatelet therapy (DAPT) consisting of a P2Y12 inhibitor and aspirin for patients following myocardial infarction (MI). The objective of this study was to evaluate the safety and effectiveness of DAPT compared to using a single antiplatelet therapy (SAPT) as part of the medical armamentarium to treat SCAD.

Methods: This review included only observational studies published in English and excluded randomized controlled trials. A comprehensive search of PubMed, Ovid, and SCOPUS was conducted to identify studies that examined SCAD outcomes including mortality, recurrence, and major adverse cardiovascular events (MACEs) between 2000-2023 after antiplatelet therapy was administered. Based on the documentation in various studies, only 17 relevant studies were identified in which SAPT (primarily aspirin) and DAPT (aspirin combined with a P2Y₁₂ inhibitor) were administered. SCAD for SAPT and DAPT groups were analyzed by calculating the mean, standard deviation (SD), range, and 95% confidence intervals (CIs). Results were reported as mean ± SD, with CIs indicating precision. Studies lacking comprehensive data on concurrent cardiovascular medication use (e.g., beta-blockers, statins) or key outcome measures were excluded.

Results: DAPT treatment was associated with a worse prognosis than SAPT 12 months after patients presented with SCAD. A key observation was the prevalence of antiplatelet treatment in SCAD patients, with DAPT prescribed in the majority of cases. DAPT demonstrated significantly higher rates of mortality (4.96% vs. 1.55%), MACE (12.13% vs. 6.91%), and hospitalizations for angina (23.75% vs. 2.60%) compared to SAPT. SCAD recurrence was also more frequent in the DAPT group (5.54% vs. 2.33%). These adverse outcomes, primarily driven by increased non-fatal MI and unplanned percutaneous coronary interventions (PCIs), highlight the challenges of DAPT in SCAD management.

Conclusions: In patients treated with antiplatelet therapy, adverse events that include unstable angina, mortality, and repeat revascularization were greater in patients with more aggressive antiplatelet therapy consisting for safety and efficacy of DAPT compared with these treated with SAPT.