Long-term Results Following Endoscopic Vein Harvesting in Coronary Artery Bypass Surgery
Condition: Angina Pectoris
MeSH terms: Angina Pectoris
Study type: Observational

Summary: 
      Vena saphena magna is still frequently used as graft material in coronary artery bypass
      grating(CABG, and vein grafts can harvest with either the conventional open technique (Ovh =
      open vein harvesting), or with less invasive endoscopic techniques (EVH = Endoscopic vein
      harvesting). The endoscopic techniques have been shown to reduce the incidence of
      postoperative wound complications while patients are more satisfied with the cosmetic result
      of the operation on the leg.

      Non-randomized studies have raised doubts about patency rates of the vein grafts following
      EVH compared to OVH, while other studies failed to detect any problems in relation to this.
      There are only very few data on long-term patency rates from randomized studies.

      The purpose of this study is to investigate clinical outcome and patency rates of the vein
      grafts following either EVH and OVH in 132 patients who underwent CABG for 4-7 years ago as
      part of a randomized study investigation wound complications. A cost-effectiveness analysis
      will also be performed.

      The hypothesis is: Patency rates following EVH are worse compared to OVH in CABG 4-7 years
      postoperatively.
    

Detailed description: 
      Background

      Vena saphena magna is frequently used as graft material in coronary artery bypass grafting
      (CABG. Vein grafts can be harvested with conventional open technique (OVH = open vein
      harvesting), or with various endoscopic less invasive techniques (EVH = Endoscopic vein
      harvesting). The endoscopic techniques have been shown to reduce the incidence of
      postoperative wound complications and patients are more satisfied with the cosmetic surgery
      results.

      Non-randomized trials, however, cast doubt on the patency rates of the vein grafts following
      EVH compared to OVH, while other studies including one randomized trial failed to detect any
      problems regarding this. There are no data regarding long-term patency rate following EVH.

      It is therefore valuable to conduct a secondary follow-up among CABG patients who 4-7 years
      ago were included in a randomized trial focusing on wound complications from the leg.
      Although the study was not designed to evaluate the clinical results and patency rates of
      vein graft, such a study may still contribute with important knowledge because the results
      will come from a randomized patient cohorts, in contrast to results from most other studies.

      Purpose

      To investigate long-term patency rates (4-7 years) patency rates and clinical outcomes
      following EVH and OVH in first-time CABG.

      We also want to perform a health economic analysis (cost-effectiveness analysis) to assess
      which of the two harvesting methods.

      Hypotheses:

        1. Patency rates following EVH are worse compared to OVH in CABG 4-7 years postoperatively.

        2. EVH is associated with an increased incidence of recurrence of angina and the need for
           re-revascularization compared with OVH.

        3. Although EVH immediately leads to higher direct costs compared with OVH, there is a
           health economic benefit of this method in the long run.

      Methods:

      This experiment consists of a follow-up among 129 of 132 former patients who underwent
      first-time CABG between April 2004 - June 2007 at Aalborg Hospital, Aarhus University
      Hospital, Denmark, comparing EVH and OVH. Register data will be collected and patient records
      will be reviewed. Surviving patients will be invited for a clinical evaluation. CT-angio in
      order to compare long-term patency rates of the vein grafts will be performed. Furthermore
      the incidence of recurrent angina, acute coronary syndrome, need for re-revascularization and
      cardiovascular death since the operation wil be evaluated.

      All direct and indirect costs of the two methods of surgery and throughout the postoperative
      course until this study will be valued in order to perform a health economic analysis
      (cost-effectiveness analysis).

      Subjects The age of the previous trial subjects was 65 years (range 43-90 years, at the time
      they were included in the previous study, and survivors will be 4-7 years old today.

      It is expected that most of the surviving former patients will participate in the study.

      Inclusion Criteria

      All 129 former patients who were included in the initial trial may be included. Deceased
      patients are only included in the trial regarding registry data and medical records.

      Exclusion criteria (in relation to the clinical examination):

      Lack of consent. (Register Data for previous patients who did not give their informed consent
      for a clinical follow-up may be included in the study)

      Exclusion criteria (in relation to CT-angio):

      Former patients with at least one of the following exclusion criteria will not have a
      CT-angio performed:

      p-creatinine> 120 micromol / l Estimated GFR (eGFR = estimated glomerular filtration rate)
      per 1.73 m2 <60 ml / min.

      Atrial fibrillation Allergy to contrast media Pregnancy Breastfeeding Lack of consent
    

Intervention name(s): Surgery
Intervention type(s): Procedure
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        A total of 132 patients who underwent CABG 4-7 years ago. All patients participated in a
        randomized study focusing on wound complications from the leg following either open or
        endoscopic vein harvest.