title: Serial morphological and functional assessment of drug-eluting balloon for in-stent restenotic lesions: mechanisms of action evaluated with angiography, optical coherence tomography, and fractional flow reserve.
abstract: OBJECTIVE
  This study sought to elucidate the underlying mechanism through which drug-eluting balloons (DEB) restore coronary blood flow, by assessing the coronary vessel before, immediately after, and at 6-month follow-up with angiography, optical coherence tomography (OCT), and fractional flow reserve (FFR).
  
  
  BACKGROUND
  In-stent restenosis (ISR) treatment remains challenging. Drug-eluting balloons have been shown to be a valid treatment option in several studies. These studies focused on efficiency of the device, whereas the mechanisms of action of DEB in ISR treatment have not been investigated.
  
  
  METHODS
  In this prospective, single-center observational study, patients with ISR were treated with a second-generation DEB. Serial angiographic, OCT, and FFR measurements were performed before and after the procedure, as well as at 6-month follow-up.
  
  
  RESULTS
  Twenty-five patients were assigned to DEB treatment, with an angiographic and device success of 100% and 92%, respectively. Late luminal loss was 0.01 ± 0.43 mm. Median percent changes [interquartile range] between pre-and post-procedure, and post-procedure and follow-up were, respectively: lumen volume 75.1% increase [43.7 to 115.0], and 8% increase [-14.0 to 25.8]; stent volume 23.7% increase [15.5 to 40.0], and -1.2% decrease [-6.9 to 5.9]; and neointimal volume -14.4% decrease [-29.2 to -9.5], and -15.8% decrease [-38.1 to 28.3]. The FFR gradient along the treated stent (difference in FFR between the distal and the proximal stent edge) was 0.37 ± 0.18 pre-procedure, 0.06 ± 0.04 post-procedure, and 0.05 ± 0.05 at follow-up. In all post-procedural OCT images, intrastent dissections were seen, which were sealed at follow-up OCT.
  
  
  CONCLUSIONS
  DEB restore coronary blood flow by means of a short-term mechanical effect, causing an increase in lumen and stent volumes and compression of neointimal hyperplasia (with intra-stent dissections). Due to the local drug effect, patency persists and may even improve at follow-up, with further increase in lumen volume, decrease in neointimal volume, and complete sealing of neointimal dissections.
authors.affiliation: Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands. agostonipf@gmail.com
authors.forename: Pierfrancesco
authors.initials: P
authors.lastname: Agostoni
authors.forename: Anouar
authors.initials: A
authors.lastname: Belkacemi
authors.forename: Michiel
authors.initials: M
authors.lastname: Voskuil
authors.forename: Hendrik M
authors.initials: HM
authors.lastname: Nathoe
authors.forename: Pieter A
authors.initials: PA
authors.lastname: Doevendans
authors.forename: Pieter R
authors.initials: PR
authors.lastname: Stella
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D006328:Cardiac Catheterization; D062906:Cardiac Catheters; D002317:Cardiovascular Agents / Q000008:administration & dosage*; D016009:Chi-Square Distribution; D023903:Coronary Restenosis / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D004337:Drug Carriers; D004867:Equipment Design; D005260:Female; D053805:Fractional Flow Reserve, Myocardial; D006801:Humans; D008297:Male; D008875:Middle Aged; D058426:Neointima; D009426:Netherlands; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015607:Stents; D013997:Time Factors; D041623:Tomography, Optical Coherence; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014654:Vascular Patency
chemical_list: D002317:Cardiovascular Agents; D004337:Drug Carriers