title: Prolonged high-pressure is required for optimal stent deployment as assessed by optical coherence tomography.
abstract: OBJECTIVE
  Optimizing stent deployment is important for both acute- and long-term outcomes. High-pressure balloon inflation is the standard for coronary stent implantation. However, there is no standardized inflation protocol. We hypothesized that prolonged high-pressure balloon inflation until stabilization of inflation pressure is superior to a rapid inflation/deflation sequence for both stent expansion and strut apposition.
  
  
  RESULTS
  A high-pressure rapid inflation/deflation sequence was deployed followed by angiography to assure no residual stenosis. Optical coherence tomography (OCT) was then performed followed by prolonged inflation until balloon pressure was stabilized for 30 sec using the same balloon at the same pressure as the rapid sequence. A second OCT run was then done. Thirteen thousand nine hundred thirteen stent struts were evaluated by OCT in 12 patients undergoing successful stenting. Stent expansion improved with prolonged (206 ± 115 sec) vs. rapid (28 ± 17 sec) inflation for both minimal stent diameter (3.0 ± 0.5 vs. 2.75 ± 0.44 mm, P < 0.0001) and area (7.83 ± 2.45 vs. 6.63 ± 1.85 mm(2) , P = 0.0003). The number of malapposed struts decreased (45 ± 41 vs. 88 ± 75, P = 0.005) as did the maximal malapposed strut distance (0.31 ± 0.2 vs. 0.43 ± 0.2 mm, P = 0.0001). Factors related to strut malapposition after rapid inflation included localized asymmetry in 67%, stent underexpansion in 75%, and stent undersizing in 67%.
  
  
  CONCLUSIONS
  These data demonstrate that prolonged inflation is superior to a rapid inflation/deflation technique for both stent expansion and strut apposition. We recommend for routine stent deployment a prolonged inflation protocol as described above to optimize stent deployment.
authors: Central Arkansas Veterans Health System, Division of Cardiology, University of Arkansas for Medical Sciences, Little Rock, Arkansas.
authors: Jeffrey R
authors: JR
authors: Cook
authors: Ajay
authors: A
authors: Mhatre
authors: Fen Wei
authors: FW
authors: Wang
authors: Barry F
authors: BF
authors: Uretsky
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods*; D017023:Coronary Angiography; D023921:Coronary Stenosis / Q000175:diagnosis / Q000628:therapy*; D054855:Drug-Eluting Stents; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011312:Pressure; D011446:Prospective Studies; D011474:Prosthesis Design; D041623:Tomography, Optical Coherence; D016896:Treatment Outcome
keywords: drug eluting stent; optical coherence tomography; percutaneous coronary intervention; stent apposition; stent deployment; stent expansion