Angina: coumarin and aspirin started before PTCA reduced clinical events compared with aspirin alone, but increased the risk of bleeding

Clinical bottom line (level 1b)

  1. Patients who started coumarin and aspirin before undergoing PTCA compared with aspirin alone were less likely to die, have a myocardial infarction, stroke or require revascularisation (NNT = 17 at 12 months) .
  2. Patients who took coumarin and aspirin compared with aspirin alone were more likely to suffer major bleeding (NNH = 48 at 12 months) or minor bleeding (NNH = 28 at 12 months) .
ten Berg et al: Circulation 2000; 102 : 386-391
Expires October 2003

The study

Unblinded ?concealed randomised trial with intention-to-treat
Setting: 2 acute hospitals, the Netherlands

1058 patients (aged mean 60, 78% male) with symptomatic coronary artery disease plannign to undergot PTCA

Excluded if
  • acute myocardial infarction within 24 hours
  • current use of oral anticoagulants
  • contraindications to coumarins or aspirin
  • target lesion in a bypass graft

Control Group: (n = 528, 528 analysed): aspirin 300 mg loading dose at least 24 hours before procedure then 100 mg daily
Experimental Group: (n = 530, 530 analysed): coumarin started before PTCA and continued for 6 months, adjusted so INR 2.1 to 4.8 and aspirin 300 mg loading dose at least 24 hours before PTCA, followed by 100 mg daily
Heparin was only used during the procedure - 10000 units before, and 5000 units per hour. All patients had groin compression with a mechanical device for 1 hour, followed by a pressure bandage for 12 hours.
100% followed for 12 months
Outcome notes:
  • major event : death, myocardial infarction, stroke, or revascularisation required
  • major bleed : causing hospitalization or death
  • minor bleed : discontinuation of study medication without need for hospitalization

The evidence

Outcome Time to outcome CER EER RRR
(95% CI)		 ARR
(95% CI)		 NNT
(95% CI)
major event 12 months 107
(20.3%)		 76
(14.3%)		 29%
(7% to 46%)		 5.93%
(1.38% to 10.5%)		 17
(10 to 72)
major bleed 12 months 1
(0.19%)		 12
(2.26%)		 -1100%
(-9060% to -56%)		 -2.07%
(-3.39% to -0.76%)		 -48
(-130 to -29)
minor bleed 12 months 2
(0.38%)		 21
(3.96%)		 -950%
(-4300% to -150%)		 -3.58%
(-5.32% to -1.84%)		 -28
(-54 to -19)

Citation

  1. ten Berg JM, Kelder JC, Suttorp MJ, et al: effect of coumarins started before coronary angioplasty on acute complications and long-term follow-up: a randomized trial. Circulation 2000; 102 : 386-391
Contributor: Chris Ball, October 2001
Reviewer:

Clinical Question.
Patient coronary artery disease awaiting PTCA
Intervention or Exposure coumarin and aspirin
Comparison aspirin
Outcome death, myocardial infarction, stroke, revascularisation