Study of Unprotected Left Main Stenting Versus Bypass Surgery (LE MANS Study)
Condition: Coronary Artery Stenosis; Myocardial Revascularization; Myocardial Ischemia
MeSH terms: Myocardial Ischemia; Coronary Stenosis; Ischemia
Study type: Interventional
Phase: Phase 4

Summary: 
      Unprotected left main coronary artery (ULMCA) stenting, offering restoration of a native flow
      to left coronary artery, is the subject of intense investigations as a potential alternative
      to bypass surgery. The purpose of the study is to compare the short and long term results of
      unprotected left main stenting with coronary artery bypass surgery.
    

Detailed description: 
      The natural history and the results of pharmacological treatment in patients with severe
      narrowing of left main coronary artery show very poor prognosis (5 year survival less than
      50%).

      There is general agreement that surgical treatment improves 5 year survival in patients with
      left main coronary artery obstruction 3, however long term survival rate (15 year follow-up)
      is low in both groups (37% and 27% respectively in surgical and medical group). Median
      survival was longer in surgical group in general population (13.3 vs 6.6 years) , but there
      was no significant difference in patients with normal LV ejection fraction (14.7 vs 15
      years).

      With the advent of coronary stenting encouraging results were reported by several authors.
      There was high success rate 98-100% for elective procedures and in these series the mortality
      (for protected and non-protected left main) ranged from 0 to 3.4 %, and 6 month event free
      survival rate was 70-80%. Restenosis rate in stented LM varied from 10-22% for proximal LM to
      40% for distal LM. Final minimal luminal area >=7mm2 post procedure, assessed by IVUS,
      predicted low restenosis rate of 7%, while the area below <7mm2 was connected with restenosis
      of 50%. Our and other experience showed that left main in-stent restenosis can be treated
      successfully with another percutaneous intervention (including endarterectomy and balloon
      angioplasty) as well as by surgical revascularization.

      Six and 12-month survival rate depended on the LV function. Patients with LVEF>40% had
      in-hospital event free survival of 98% and 9-month event free survival of 86%, whereas
      patients with LVEF <40% had in-hospital and 9 month event-free survival of 67 and 22%
      respectively. Additionally, in patients presented with acute myocardial infarction or
      bail-out procedures, early and late results of LM stenting were not as good as for elective
      cases.

      Our previously presented promising results of left main stenting is mainly related to proper
      technique of LM stenting (short inflations within LM, careful guiding catheter manipulation,
      stent selection), as well as very cautiously designed follow-up (every month visit for first
      six month, routine coronary angiography within 3-6 months after procedure). This initial
      experience gives us the backgrounds for a larger prospective randomized trial comparing
      elective surgical revascularisation and percutaneous intervention in patients with LM
      coronary artery disease. It is our impression that design and the delivery system of the new
      generation stent is uniquely suited to safely treat this difficult subset of patients. At the
      present time we would limit the study to the discrete lesions in proximal (ostial and mid)
      left main with reference luminal diameter >=3 mm. Based on published results of stenting
      under IVUS examination for such a lesion we estimate the restenosis rate to be well below
      10%. As we expect, the survival and complication rate within one year in both group will be
      similar. Therefore our main concern is weather both treatment strategies will offer the same
      prevention of LV function, as well as improvement of functional capacity and coronary reserve
      in both groups in a period of 2-3 years.
    

Intervention name(s): Percutaneous Coronary Intervention; Coronary Artery Bypass Grafting
Intervention type(s): Procedure; Procedure
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: left main stenosis; Percutaneous Coronary Intervention; Coronary Artery Bypass Grafting