Author + information
- Michael S. Kim, MD,
- Marvin H. Eng, MD,
- Paul A. Hudson, MD,
- Joel A. Garcia, MD,
- Onno Wink, PhD,
- John C. Messenger, MD and
- John D. Carroll, MD⁎ ()
- ↵⁎University of Colorado Denver, Anschutz Medical Campus, Leprino Office Building, Room 524, 12401 East 17th Avenue, P.O. Box 6511, Campus Box B-132, Aurora, Colorado 80045
Standard angiography and intravascular ultrasound (IVUS) have limited ability to visualize stent struts and their integrity over time. While it is thought that stent fracture is associated with high incidence of restenosis or thrombosis, the true incidence of stent fracture is difficult to ascertain with current imaging modalities. New methods of digital subtraction imaging in the catheterization lab have been developed to enhance the detail of stents at the time of implantation. One such method summates imaging frames around fixed marker bands on balloon catheters which deliver the stents (StentBoost Subtract, Philips Healthcare, Best, the Netherlands). The detection of stent strut fracture during the procedure is a proposed use of the technology, but was until recently rarely used.
This report provides an example of the clinical use of an image enhancement system to confirm the diagnosis of a type IV stent fracture despite lack of IVUS evidence of stent fracture. A middle-aged patient underwent left anterior descending (LAD) intervention for typical angina. The appearance of the LAD stenosis distal to a markedly ectatic vessel segment before stent implantation (Fig. 1A) showed a significant vessel narrowing and after implantation (Fig. 1B) of a 3.0 × 9 mm open cell design bare-metal stent (Driver, Medtronic Inc., Minneapolis, Minnesota) showed satisfactory stent expansion. The IVUS images (Fig. 1C) confirmed the initial angiographic result. However, the image enhancement (Fig. 1D) demonstrated a stent strut fracture. In the fractured segment, IVUS showed complete stent expansion and vessel wall apposition, but no obvious stent fracture. The image enhancement demonstrated a type IV stent fracture (Fig. 1D, arrow). At 6-month follow-up, neither the angiographic appearance (Fig. 1E) of the LAD stent nor the IVUS (Figs. 1F) had evidence of in-stent restenosis. On examination of the image enhanced angiograms (Figs. 1G and 1H), serial static images demonstrated no significant visual change in the stent fracture (arrow). The image enhanced strategies have the potential to identify stent strut fracture.
Please note: Dr. Carroll is a consultant/investigator for Philips Healthcare.
- American College of Cardiology Foundation