Patients with coronary artery spasm responding to 20μg acetylcholine had over twice the risk of major adverse cardiovascular events (HR 2.43) compared to those responding at 100μg.
Does the first responsive dose of intracoronary acetylcholine predict long-term clinical outcomes in patients with coronary artery spasm?
Patients with coronary artery spasm who respond to a lower initial dose of acetylcholine (20μg) have a significantly higher risk of long-term adverse cardiovascular events compared to those responding at higher doses.
Absolute Event Rate: 0% vs 0%
Abstract Background Coronary artery spasm (CAS) has become a focus of recent prognostic studies. However, research evaluating prognosis based on the initial dose of acetylcholine (ACH) at which patients first respond is lacking. This study aims to investigate long-term clinical outcomes according to the first responsive dose of intracoronary ACH in patients with CAS. Methods A total of 3,783 patients with positive intracoronary provocation testing with ACH were categorized into three groups based on the dose at which they first exhibited a positive spasm response: A1 (20μg), A2 (50μg), and A3 (100μg). The primary endpoint was major adverse cardiovascular events (MACE), defined as a composite of total death, myocardial infarction, and revascularization. Secondary endpoints included major adverse cardiovascular and cerebrovascular events 1 (MACCE1), a composite of MACE and stroke, as well as MACCE2, comprised of MACCE1 and recurrent angina requiring repeat coronary angiography. Kaplan-Meier survival analysis and multivariate Cox regression were used to assess the relationship between the initial responsive dose and clinical outcomes. Results The prevalence of coronary artery stenosis was greater in the A1 group (61.1%) compared to the A2 group (56.8%) and the A3 group (58.6%). The A1 group showed the highest incidence of MACE, including total mortality and revascularization (P = 0.003, P = 0.002, and P = 0.044). MACCE2, including recurrent angina, was also significantly more frequent in the A1 group compared to the other groups (P = 0.036 and P = 0.025). Multivariate Cox regression showed a higher risk of MACE (HR 2.43, 95% CI 1.01-5.81, P = 0.047) and MACCE2 (HR 1.62, 95% CI 1.09-2.39, P = 0.016) in the A1 group compared to the A3 group. Conclusion The initial responsive dose of ACH is a potential predictor of long-term clinical outcomes in patients with coronary artery spasm. Patients who respond at lower doses may be associated with a more profound endothelial dysfunction, more vulnerability to CAS and subsequent higher risk of adverse cardiovascular events, indicating the need for tailored therapeutic strategies based on ACH responsiveness.
Ahn et al. (Sat,) reported a other. Patients with coronary artery spasm responding to 20μg acetylcholine had over twice the risk of major adverse cardiovascular events (HR 2.43) compared to those responding at 100μg.