Coronary heart disease: stent placement decreased restenosis.

Clinical bottom line (level 1b)

  1. Patients with obstructed coronary artery grafts who were given stent placement, were less likely to have restenosis than those given balloon angioplasty (NNT = 4 at 6 months) .
  2. Patients given stent placement were more likely to have bleeding and vascular complications.
  3. There was no clear difference in death, MI or coronary artery bypass grafts.
Savage et al: New England Journal of Medicine 1997; 337 (11): 740-747
Expires March 2003

The study

Unblinded ?concealed randomised trial with intention-to-treat
Setting: twelve clinical centres, USA

220 patients (aged mean 66 years, 81% male) new lesions in aortocoronary venous bypass grafts and angina pectoris, objective evidence of myocardial ischaemia, or both.

Excluded if
  • stenosis <60%
  • myocardial infarction within previous seven days
  • contraindication to aspirin, dipyridamole or warfarin
  • ejection fraction <25%
  • diffuse disease that would require >two stents
  • evidence of thrombus
  • outflow obstruction of the graft due to distal anastomotic stenosis or poor runoff in the recipient native vessel


    • Control Group: (n = 107, 107 analysed): balloon angioplasty with conventional balloon catheters. Patients were given aspirin (325 mg daily) indefinitely.
    Experimental Group: (n = 108, 108 analysed): stent placement- 15 mm long stents. Patients were given aspirin (325 mg daily) and dipyridamole (75 mg three times a day) beginning at least 24 hours before the procedure. They received iv dextran 40 and heparin during the procedure. Warfarin therapy was begun on the day of the procedure and heparin was continued until a therapeutic prothrombin time was reached.

    100% followed for 6 months
    Outcome notes:
    • no restenosis : restenosis defined as: stenosis of 50% or more of the luminal diameter at follow-up without a major cardiac complication

    The evidence

    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    no restenosis 6 months 33
    (30.8%)    		 8
    (7.41%)    		 76.0%
    (50.0% to 88.0%)    		 23.4%
    (13.4% to 33.5%)    		 4
    (3 to 7)
    bleeding and vascular complications 30 days 12
    (11.2%)    		 40
    (37.0%)    		 -230%
    (-494% to -84%)    		 -25.8%
    (-36.7% to -14.9%)    		 -4
    (-7 to -3)
    death, MI or coronary artery bypass grafts 6 months 11
    (10.3%)    		 6
    (5.56%)    		 46.0%
    (-41.0% to 79.0%)    		 4.72%
    (-2.47% to 11.9%)    		 21
    (NNT = 8 to infinity;
    NNH = 40 to infinity)

    Comments

    1. The newer antiplatelet regimes may affect the absolute improvements seen here.
    2. The use of newer stent types may also improve the results.

    Citation

    1. Savage MP, Douglas JS, Fischman DL, et al: Stent placement compared with balloon angioplasty for obstructed coronary bypass grafts. New England Journal of Medicine 1997; 337 (11): 740-747
    Contributor: Clare Wotton and Chris Ball, February 2000
    Reviewer: Deepak L Bhatt

    Clinical Question.
    Patient obstructed coronary bypass grafts
    Intervention or Exposure stent placement
    Comparison balloon angioplasty
    Outcome restenosis