Bench top evaluation and clinical experience with the Szabo technique: new questions for a complex lesion

Catheter Cardiovasc Interv. 2012 Feb 15;79(3):378-89. doi: 10.1002/ccd.23087. Epub 2011 Jul 29.

Abstract

Background: The Szabo technique has been described as a method to ensure accurate ostial stent placement. We sought to investigate this novel technique in detail both in vitro and in vivo.

Methods and results: The technique was subjected to bench testing and also undertaken in 26 patients. Each step was recorded with cine angiography and the stents imaged by microcomputed tomography. The ostial LAD was treated in 81% and a DES was implanted in 92%. Angiographic success was 88.5% (one case of stent dislodgement). Repeat angiography was performed in 78% and restenosis observed in two patients. MACE rate at 15.5 ± 5.1 months was 13% (1 TLR, 1 MI, 1 cardiac death). Despite a seemingly excellent immediate angiographic result, we report one case of restenosis at follow up and one case of IVUS examination (performed in four patients) in which significant stent protrusion, into the proximal main vessel, was observed. In vitro bench testing confirmed a significant and asymmetric (carina side) stent protrusion into the main branch, with the last cell of the stent undergoing significant deformation.

Conclusions: The Szabo technique is not a precise technique to implant a stent at the level of the ostium. The proximal end of the stent undergoes significant and asymmetric deformation, protruding into main branch. Additional concerns with this complex technique include the potential for stent damage or contamination before implantation and the risk of stent dislodgement. We conclude that there are more disadvantages than benefits to this technique which only partially addresses the difficulties encountered in the treating ostial lesions.

MeSH terms

  • Aged
  • Angioplasty, Balloon, Coronary / adverse effects
  • Angioplasty, Balloon, Coronary / instrumentation
  • Angioplasty, Balloon, Coronary / methods*
  • Angioplasty, Balloon, Coronary / mortality
  • Cineangiography / instrumentation
  • Coronary Angiography / instrumentation
  • Coronary Artery Disease / diagnostic imaging
  • Coronary Artery Disease / mortality
  • Coronary Artery Disease / therapy*
  • Coronary Restenosis / diagnostic imaging
  • Coronary Restenosis / etiology
  • Drug-Eluting Stents
  • Female
  • Humans
  • Male
  • Materials Testing
  • Middle Aged
  • Phantoms, Imaging
  • Prosthesis Design
  • Registries
  • Time Factors
  • Treatment Outcome
  • Ultrasonography, Interventional
  • X-Ray Microtomography / instrumentation