Comparison of post-stent optical coherence tomography findings among three subtypes of calcified culprit plaques in patients with acute coronary syndrome

Objectives To compare the postprocedural optical coherence tomography (OCT) findings and in-hospital outcomes among the three subtypes of calcified plaques: eruptive calcified nodules, superficial calcific sheet, and calcified protrusion. Background Recently, three subtypes of calcified culprit plaques were reported in patients with acute coronary syndrome (ACS). How these subtypes respond to stenting is unknown. Methods ACS patients with calcified plaque at the culprit lesion were selected from our database. OCT findings at baseline and after stent implantation were compared. Results In the final analysis, 87 cases were included. Preprocedural OCT showed eruptive calcified nodules in 19 (21.8%) cases, superficial calcific sheet in 63 (72.4%), and calcified protrusion in 5 (5.7%). Stent edge dissection (SED) and incomplete stent apposition (ISA) were frequently observed in the eruptive calcified nodules group compared to superficial calcific sheet or calcified protrusion (SED; 47.4% vs. 17.5% vs. 20.0%;p= .032, ISA; 94.7% vs. 58.7% vs. 0.0%;p < .001). The superficial calcific sheet group had the smallest minimal stent area (MSA) among the three groups (eruptive calcified nodules vs. superficial calcific sheet vs. calcified protrusion: 6.29 +/- 2.41 vs. 4.72 +/- 1.37 vs. 6.56 +/- 1.13;p= .007). The superficial calcific sheet group had a higher rate of periprocedural myocardial infarction compared to the eruptive calcified nodules group (60.3% vs. 31.6%;p= .028). Conclusions This study demonstrated eruptive calcified nodules are associated with higher incidence of SED and ISA, whereas superficial calcific sheets are associated with small MSA and higher periprocedural myocardial infarction.