Association of Spontaneous Coronary Artery Dissection With Atrial Arrhythmias

The co-morbidities and long-term complications of spontaneous coronary artery dissection (SCAD) are incompletely understood. This study investigated the association of atrial arrhythmias (AA), defined as atrial fibrillation and atrial flutter, with SCAD in a patient registry and population-based cohort. This observational study was performed in 2 parts. The first was a retrospective study reviewing patients diagnosed with AA in the Mayo Clinic SCAD Registry. The second was a population-based, case-control study to assess AA in patients with SCAD compared with age- and gender-matched controls. Of 1,214 patients in the Mayo Clinic SCAD Registry, 45 patients (3.7%) with SCAD were identified with an AA. A total of 8 of those patients (17.8%) had a pre-SCAD AA; 20 (44.4%) had a peri-SCAD AA; and 17 (37.8%) had a post-SCAD AA. The univariate analysis did not reveal significant associations with traditional cardiovascular risk factors. In the population-based cohort, 5 patients with SCAD (4%) and 4 controls (1%) developed an AA before the date of SCAD for each patient (odds ratio 4.5, 95% confidence interval [CI] 1.05 to 19.0, p = 0.04). A total of 5 patients with SCAD (4%) and 3 controls (1%) developed an AA in the 10 years after SCAD (hazard ratio 6.3, 95% CI 1.2 to 32.8, p = 0.03). A subgroup of patients with SCAD experienced AA before and after SCAD. Patients with a history of SCAD were more likely to develop AA in the next 10 years than were age- and gender-matched healthy controls.