Author + information
- Hiromasa Otake, MD,
- Junya Shite, MD⁎ ( and )
- Junya Ako, MD
- ↵⁎Kobe University Graduate School of Medicine, Division of Cardiovascular and Respiratory Medicine, 7-5-2 Kusunoki-Cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan
We thank Dr. Kaneda for his interest and comments on our recent publication (1). Dr. Kaneda suggested an additional within-patient analysis comparing stent expansion index (SEI) (minimum/maximum stent diameter) between segments with and without thrombus. This is an important suggestion to examine more local determinants on the presence of thrombus.
In our study, we demonstrated that the average SEI was associated with the presence of subclinical thrombus after sirolimus-eluting stent (SES) implantation (SEI: SES with thrombus: 0.89 ± 0.04 vs. SES without thrombus: 0.92 ± 0.03; p = 0.001). Our results simply suggest, as stated by Guagliumi and Costa (2) in their editorial comment on our study, that the lesions with lower average SEI were more likely to have thrombus somewhere in the stented segment. In our study, however, even in SES without thrombus, there were segments showing suboptimal symmetry. Indeed, the average value of minimum SEI was not statistically different between SES with and without thrombus (0.80 ± 0.07 vs. 0.77 ± 0.06, respectively; p = 0.15). According to detailed cross-sectional optical coherence tomography (OCT) analysis from 14 lesions with thrombus, the segments with thrombus showed comparable SEI with segments without thrombus (segments without thrombus: 0.88 ± 0.04 vs. segments with thrombus: 0.87 ± 0.06). From these observations, we speculate that: 1) the average symmetrical property throughout the stented segment is important rather than the mere existence of segment(s) with asymmetric expansion; 2) thrombus seems to form at the segment whose SEI is at least comparably low as compared with other segments in the same stents (the SEI of the segment with thrombus appears smaller than the average SEI of SES without thrombus); and 3) thrombus does not necessarily form at the most asymmetric segment throughout the stented segment.
We feel that, considering the low statistical power with the small number of patients in this study, a study involving a larger population would be necessary to confirm these findings. However, the greater resolution of OCT might have the potential to provide more detailed information after stenting.
- American College of Cardiology Foundation
- Otake H.,
- Shite J.,
- Ako J.,
- et al.
- Guagliumi G.,
- Costa M.