Pure Saline OCT
Dr. Karl Chi-yuen CHAN
Prince of Wales Hospital, Hong Kong
A 73-year-old female enjoyed good past health until 3 months before admission. She presented with on and off chest discomfort for 3 months. She noted to have recurrence of chest discomfort 3 days. ECG showed anterior ST segment elevation (Figure 1). Her chest discomfort improved with Aspirin and sublingual nitrate. Repeat ECG showed ST segment resolution.
Urgent Coronary angiogram was performed via right radial approach. 6Fr Ikari-Left guide was used. It showed a tight mid LAD lesion (Movie 1a, Movie 1b, Movie 1c). The lesion was wired and pre-dilated with 2.0mm balloon. Pre-OCT was done by pure saline injection (Movie 2a, Movie 2b). 2.25 x 38mm DES was deployed at nominal pressure. Post-stenting angiogram showed stenosis at diagonal ostium due to plaque shifting (Movie 3). Diagonal branch was wired. OCT was performed with pure saline injection (Movie 4a, Movie 4b). Whole stented segment was post-dilated with NC 2.25mm balloon. It was planned to balloon the diagonal ostium and completed with kissing balloon with NC 2.25mm balloon at main branch. However, 2.0mm balloon was not able to deliver into diagonal branch. On careful OCT study on the 2nd OCT run (post-stented OCT run), the diagonal wire was found running underneath the first ring of struts (Movie 5a, Focus OCT run at proximal stent edge; Movie 5b, 3D reconstruction of proximal stent edge; Figure 2, Carpet view of OCT showing wire underneath the strut). Diagonal wire was retrieved and rewired. Diagonal branch was post-dilated and completed with kissing balloon with NC 2.25mm balloon at distal main branch. Proximal main branch was further post-dilated with NC 3.0mm balloon as POT technique. Final OCT with pure saline and angiogram showed perfect stenting result (Movie 6a, Movie 6b, Movie 7).
This case illustrates that OCT can be done with pure saline on selected case. And the image quality is good enough for 3D reconstruction.