Acute Thrombus Burden on Coated Flow Diverters Assessed by High Frequency Optical Coherence Tomography

Cardiovasc Intervent Radiol. 2020 Aug;43(8):1218-1223. doi: 10.1007/s00270-020-02482-w. Epub 2020 May 8.


Purpose: The implantation of flow diverters requires administration of dual anti-platelet therapy, posing the potential for complications. The p48MW HPC (phenox, Bochüm, Germany) hydrophilic-coated flow diverting stent is designed to be anti-thrombotic, thus opening the potential for single anti-platelet therapy. We deploy a novel intravascular high-resolution imaging technique, high-frequency optical coherence tomography (HF-OCT), to study in an animal model the acute thrombus formation on coated p48MW devices versus uncoated control devices.

Methods: Three pigs were implanted with 4 flow diverters each, two test hydrophilic-coated devices, and two control uncoated devices (p48MW). Each pig was treated with a different anti-platelet regime: no anti-platelet therapy, aspirin only, aspirin and clopidogrel. Twenty minutes after the flow diverter was implanted, an HF-OCT data set was acquired. Acute clot formed on the flow diverter at each covered side branch was measured from the HF-OCT slices. Factors considered to be important were the device type (pHPC versus bare metal), aspirin, clopidogrel, and vessel location. A linear model was constructed from the significant factors.

Results: Both coating (p < 0.001) and aspirin (p = 0.003) were significantly related to reduction in clot burden, leading to an approximate 100-fold and 50-fold reduction in clot, respectively.

Conclusions: This study shows the power of HF-OCT not only in the detection of clot but also the quantification of clot burden. In an animal model, the pHPC-coated p48MW significantly reduced acute thrombus formation over jailed side branches as compared to the bare metal p48MW that was nearly eliminated when combined with aspirin administration.

Keywords: Flow diverter; Hydrophilic coating; Optical coherence tomography; Stents; Thrombus.

MeSH terms

  • Acute Disease
  • Animals
  • Aspirin / therapeutic use*
  • Clopidogrel / therapeutic use*
  • Coated Materials, Biocompatible
  • Disease Models, Animal
  • Platelet Aggregation Inhibitors / therapeutic use*
  • Stents*
  • Swine
  • Thrombosis / diagnostic imaging*
  • Thrombosis / prevention & control
  • Tomography, Optical Coherence / methods*


  • Coated Materials, Biocompatible
  • Platelet Aggregation Inhibitors
  • Clopidogrel
  • Aspirin