Association Of Pregnancy With Recurrence Of Spontaneous Coronary Artery Dissection Among Women With Prior Coronary Artery Dissection

Question What is the risk of recurrent spontaneous coronary artery dissection (SCAD) with pregnancy in women with a history of coronary artery dissection? Findings In this nested case-control study of 636 women, there was no difference in exposure to pregnancy after SCAD among women with recurrent SCAD as compared with matched women without recurrent SCAD. There was no association between subsequent pregnancy and recurrent SCAD at 5 years' follow-up in the overall cohort. Meaning This study found no evidence for increased risk of SCAD recurrence among women who became pregnant after SCAD, but results are limited by the small total number of women with normal left ventricular ejection fraction at time of subsequent pregnancy and should be interpreted with caution.Importance Spontaneous coronary artery dissection (SCAD) is a notable cause of acute coronary syndrome in women of childbearing age. Objective To test the hypothesis that pregnancy after SCAD is associated with recurrent SCAD. Design, Setting, and Participants Three study designs were implemented: a case series of women with pregnancy after SCAD; a nested case-control study comparing patients with recurrent SCAD to matched controls without recurrent SCAD; and a cohort study. Women with SCAD who were of childbearing potential and enrolled into the Mayo Clinic SCAD Registry from August 30, 2011, to April 4, 2019, were included in the study. Patients with coronary dissections associated with iatrogenesis, trauma, or atherosclerosis were not enrolled. Exposures Pregnancy after SCAD. Main Outcomes and Measures The primary outcome was SCAD recurrence, defined as an acute coronary syndrome or cardiac arrest due to new SCAD. Other demographic measures collected included age, year of SCAD occurrence, and comorbidities. Results The cohort included 636 women of childbearing potential. Twenty-three of those women had a total of 32 pregnancies after SCAD. The median (interquartile range) age of women with pregnancy after SCAD was 38 years (34-40 years), and 20 (87%) were White. In the nested case-control study, 92 cases of recurrent SCAD were matched to 158 controls. There was no significant difference in exposure to subsequent pregnancies in the women with recurrent SCAD as compared with matched controls (2 of 92 [2%] vs 13 of 158 [8%]; P = .06). In the overall cohort of 636 patients, recurrent SCAD was present in 122 patients with a Kaplan-Meier 5-year SCAD recurrence estimate of 14.8%. The Cox analysis showed no significant association between subsequent pregnancy and SCAD recurrence with a nonsignificant hazard ratio of 0.38 (95% CI, 0.09-1.6) when controlling for age at first SCAD, year of first SCAD, and fibromuscular dysplasia. Conclusions and Relevance This study found that most women tolerated pregnancy and lactation after SCAD without evidence for increased risk of SCAD recurrence when compared with women with a history of SCAD who did not experience pregnancy. Although this study is reassuring and indicates complex contributors to SCAD recurrence, the results need to be interpreted prudently because of study selection bias and the small total number of women who became pregnant after SCAD. The notable hemodynamic changes that occur with pregnancy and severe presentation of pregnancy-associated SCAD are reasons for concern when considering pregnancy after SCAD.This nested case-control study uses data from the Mayo Clinic Spontaneous Coronary Artery Dissection Registry to investigate the association of pregnancy with spontaneous coronary artery dissection recurrence among women with a history of coronary artery dissection.