[The relationship between variant angina pectoris syncope and coronary artery spastic targeted location, arrhythmia...

Objective: Investigation of the relationship between variant angina pectoris syncope and coronary artery spastic targeted location, arrhythmias, and coronary artery stenostic lesion. Methods: This study combined retrospective and prospective registry approaches. Data were sourced from the case database of Henan province "Multicenter Clinical Observation Study of Variant Angina Pectoris". A total of 507 patients with variant angina pectoris who had complete records from June 1980 to December 2022 were consecutively enrolled. Select patients among them who experienced syncope, and analyze the target vessel sites of coronary artery spasm, arrhythmias during variant angina pectoris attacks, and the degree of stenosis in coronary artery lesions. Results: Among 507 variant angina pectoris patients, 88 experienced syncope. Age was (53.9±9.7) years and 66 patients (75.0%) were male. Forty patients (45.5%, 40/88) were aged 50-59 years. The incidence of syncope in variant angina pectoris caused by left anterior descending artery (LAD) spasm, right coronary artery (RCA) spasm, and multivessel coronary artery spasm was 7.4% (15/202), 22.7% (42/185), and 23.6% (25/106), respectively. The latter two were significantly higher than those in the LAD group (P all<0.05). Among 77 patients with variant angina pectoris syncope, definitive electrocardiogram recordings were available during syncope episodes. All patients exhibited arrhythmias during syncope: 34 cases involved tachyarrhythmias and 43 cases involved bradyarrhythmias. The incidence of rapid arrhythmias in patients with LAD, RCA, and multi-vessel spasm syncope was 72.7% (8/11), 24.3% (9/37), and 54.2% (13/24), respectively, with P<0.05 for the first two. Bradyarrhythmias occurred in 27.3% (3/11) of LAD, 75.7% (28/37) of RCA, and 45.8% (11/24) of multivessel coronary artery spasm syncope cases, with the first two showing P<0.05. Coronary angiography analysis of 56 syncope patients revealed target vessel locations and stenosis severity: 12 patients had LAD lesions and 41 had RCA lesions, stenosis ≥50% occurred in 66.7% (8/12) and 43.9% (18/41) of these lesions, respectively (P>0.05). Conclusions: Variant angina pectoris syncope predominantly affects middle-aged males. Bradyarrhythmias triggered by RCA spasm are a common cause, while the incidence of syncope shows no significant correlation with the degree of coronary artery stenostic lesion, whether in the LAD or the RCA.