Author + information
- Received November 4, 2008
- Accepted November 5, 2008
- Published online March 1, 2009.
- Lakshmana K. Pendyala, MD,
- Jinsheng Li, MD, PhD,
- Toshiro Shinke, MD, PhD,
- Sarah Geva, PhD,
- Xinhua Yin, MD, PhD,
- Jack P. Chen, MD, FACC,
- Spencer B. King III, MD, MACC,
- Keith A. Robinson, PhD, FACC,
- Nicolas A.F. Chronos, MD, FACC and
- Dongming Hou, MD, PhD, FACC⁎ ()
- ↵⁎Reprint requests and correspondence:
Dr. Dongming Hou, Saint Joseph's Translational Research Institute/Saint Joseph's Hospital of Atlanta, 5673 Peachtree Dunwoody Road, Suite 675, Atlanta, Georgia 30342
Objectives We sought to evaluate coronary epicardial and intramyocardial resistance, arterial vasomotor function, local inflammatory reaction, and superoxide anion (O2· −) production after overlapping paclitaxel-eluting stent (PES) implantation in a porcine model.
Background PES implantation has been shown to elicit coronary vasomotor dysfunction. However, underlying mechanisms remain largely unknown.
Methods Nine pigs received overlapping PES and bare-metal stents (BMS) in the coronary arteries, and 3 sham animals were naïve. At 1 month, inflammatory response at the overlapped region was assessed by histopathology and scanning electron microscopy. Endothelial vasomotor function and O2· − at nonstented coronary reference segments were measured by angiography and organ chamber tensiometry, and lucigenin luminometry; vasomotor function of distal resistance arteries was measured by myography.
Results Paclitaxel-eluting stents showed reduced late lumen loss, but inflammation and luminal inflammatory cell adherence were higher than for BMS (p < 0.001) at overlapped segments. Endothelium-dependent relaxation to substance P was significantly impaired in PES at nonstented coronary reference segments (≥15 mm proximally and distally) and perfusion bed resistance arteries (p < 0.05). In contrast, endothelium-independent relaxation to nitroglycerin and sodium-nitroprusside was similar between groups. Local O2· − production at both proximal and distal nonstented coronary reference segments was elevated for PES when compared with O2· − production in BMS and naïve arteries (p < 0.001).
Conclusions Abnormal endothelium-dependent relaxation at both coronary conduit and resistance arteries was demonstrated after overlapping PES implantation. Profound localized inflammatory reaction, as well as enhanced local oxidative stress, may contribute to vasomotor dysfunction.
Supported by a Saint Joseph's Translational Research Institute research grant, but contents of the manuscript are solely the responsibility of the authors. Steven Nissen, MD, MACC, served as Guest Editor for this paper.
- Received November 4, 2008.
- Accepted November 5, 2008.
- American College of Cardiology Foundation