title: Determinants of target vessel failure in chronic total coronary occlusions after stent implantation. The influence of collateral function and coronary hemodynamics.
abstract: OBJECTIVE
  The goal of this study was to assess the influence of collateral function, coronary hemodynamics, and the angiographic result on the risk of target vessel failure (TVF) after recanalization of a chronic total coronary occlusion (CTO).
  
  
  BACKGROUND
  Collaterals may have an adverse effect on TVF.
  
  
  METHODS
  In 111 consecutive patients, a CTO (duration >2 weeks) was successfully recanalized with stent implantation. Collateral function was assessed by intracoronary Doppler flow velocity and pressure recordings distal to the occlusion. Baseline collateral function was determined before the first balloon inflation, and recruitable collateral function after stenting during a balloon reocclusion. Finally, the coronary flow velocity reserve (CFVR) and the fractional flow reserve (FFR) were measured.
  
  
  RESULTS
  Angiographic follow-up after 5 +/- 4 months in 106 patients showed a reocclusion in 17% and a restenosis in 36%. The major determinants of TVF were the stent length (p < 0.01) and number of implanted stents (p < 0.01). No difference was observed in baseline or recruitable collateral function between patients with and without TVF; 52% of patients had a CFVR >or= 2.0, and only 18% a CFVR >or=2.5 after percutaneous transluminal coronary angioplasty, but neither cutoff-value predicted TVF. A low FFR discriminated patients with reocclusion (0.81 +/- 07 vs. 0.86 +/- 08, p < 0.05) but not with restenosis (0.87 +/- 0.06).
  
  
  CONCLUSIONS
  This study showed that there is no relation between a well-developed collateral supply and the risk of TVF in recanalized CTOs. This was rather determined by the stented segment length. There was also no adverse effect of the frequently observed impaired CFVR on TVF, whereas a low FFR was associated with a higher risk of reocclusion.
authors.affiliation: Clinic for Internal Medicine III, Friedrich-Schiller-University, Jena, Germany. gerald.werner@med.uni-jena.de
authors.forename: Gerald S
authors.initials: GS
authors.lastname: Werner
authors.forename: Philipp
authors.initials: P
authors.lastname: Bahrmann
authors.forename: Oliver
authors.initials: O
authors.lastname: Mutschke
authors.forename: Ulf
authors.initials: U
authors.lastname: Emig
authors.forename: Stefan
authors.initials: S
authors.lastname: Betge
authors.forename: Markus
authors.initials: M
authors.lastname: Ferrari
authors.forename: Hans R
authors.initials: HR
authors.lastname: Figulla
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects* / Q000295:instrumentation; D001783:Blood Flow Velocity; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects* / Q000295:instrumentation; D003097:Collateral Circulation; D015986:Confounding Factors, Epidemiologic; D017023:Coronary Angiography; D003326:Coronary Circulation; D003327:Coronary Disease / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy*; D016002:Discriminant Analysis; D015150:Echocardiography, Doppler; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors; D015607:Stents / Q000009:adverse effects*; D017211:Treatment Failure