Natural History of Spontaneous Coronary Artery Dissection With Spontaneous Angiographic Healing.

OBJECTIVES

Given the uncertainty regarding the degree and prevalence of spontaneous healing following spontaneous coronary artery dissection (SCAD), the aim of this study was to assess the angiographic characteristics of the dissected segments in a large cohort of patients with SCAD who underwent subsequent repeat coronary angiography.

BACKGROUND

SCAD is an uncommon yet important cause of myocardial infarction in women. Very little is known about the characteristics of healing of dissected arteries.

METHODS

Patients with nonatherosclerotic SCAD followed prospectively at Vancouver General Hospital who underwent repeat angiography were included in this study. Those who underwent percutaneous coronary intervention for SCAD were excluded. Baseline patient demographics and in-hospital and long-term cardiovascular events were recorded. Angiographic characteristics of the SCAD artery at index and repeat angiography were assessed by 2 experienced angiographers. Criteria for angiographic healing were as follows: 1) improvement of stenosis severity from index event; 2) residual stenosis <50%; and 3) TIMI (Thrombolysis In Myocardial Infarction) flow grade 3.

RESULTS

One hundred fifty-six patients with 182 noncontiguous SCAD lesions were included. The mean age was 51.5 ± 8.7 years, 88.5% were women, 83.3% were Caucasian, and 75.6% had fibromuscular dysplasia. All patients presented with myocardial infarction. At index angiography, type 2 SCAD was most commonly observed, in 126 of 182 lesions (69.2%); TIMI flow grade <3 was present in 85 of 182 (46.7%); and median lesion stenosis was 79.0% (interquartile range: 56.0% to 100%). Median time to repeat angiography was 154 days (interquartile range: 70 to 604 days), with median residual lesion stenosis improving to 25.5% (interquartile range: 12.0 to 38.8 days), and TIMI flow grade <3 observed in 10 of 182 lesions (5.5%). Angiographic healing occurred in 157 of 182 lesions (86.3%). Of repeat angiography performed ≥30 days post-SCAD, 152 of 160 (95%) showed spontaneous angiographic healing.

CONCLUSIONS

The majority of coronary arteries affected by SCAD heal spontaneously on repeat angiography, with apparent time dependency, with the vast majority having complete healing after 30 days from the SCAD event.