Acute coronary syndrome: an early invasive strategy using tirofiban reduced death, non-fatal MI and readmission with acute coronary syndrome

Clinical bottom line (level 1b)

  1. Patients with unstable angina or myocardial infarction without ST elevation who received an early invasive strategy with tirofiban compared with an early conservative strategy with tirofiban were less likely to die, have a non-fatal myocardial infarction or require readmission with an acute coronary syndrome (NNT = 28 at 6 months) .
  2. Patients who received an early invasive strategy were less likely to have a myocardial infarction (NNT = 47 at 6 months) .
  3. Patients who received an early invasive strategy were more likely to undergo coronary angiography (NNT = 3 at 6 months) , angioplasty (NNT = 8 at 6 months) or CABG (NNT = 17 at 6 months) .
Cannon et al: New Engl J Med 2001; 344 : 1879-1887
Expires March 2004

The study

Double-blinded concealed randomised trial without intention-to-treat
Setting: over 25 acute hospitals, USA

2220 patients (aged mean 62, 66% male) with unstable angina (accelerating pattern or > 20 minute episodes of chest pain, or recurrent episodes at rest or with minimal effort) and at least one of
  • new ST depression of at least 0.5 mm, transient (< 20 min) ST elevation of at least 1 mm, or T wave inversion of at least 3 mm in 2 or more leads
  • elevated cardiac markers
  • history of coronary disease from catheterisation, revascularisation or myocardial infarction


Excluded if
  • persistent ST elevation
  • secondary angina
  • PTCA or CABG within previous 6 months
  • factors associated with an increased risk of bleeding
  • LBBB or paced rhythm
  • severe congestive heart failure or cardiogenic shock
  • serious systemic disease
  • serum creatinine > 220 micromol/l (2.5 mg/dl)
  • participating in another study
  • taking warfarin or received ticlopidine or clopidogrel for more than 3 days before enrollment
  • aged < 18
  • not a candidate for coronary revascularisation

Control Group: (n = 1106, 1106 analysed): early conservative therapy: medical therapy. If stable, patients underwent exercise-tolerance testing (83% included nuclear imaging or echocardiography). Patients underwent coronary angiography and revascularisation if they had prolonged or recurrent angina at rest with ECG signs of ischaemia or changes in cardiac markers; haemodynamic instability; documented ischaemia before the end of Bruce protocol stage 2 or at any time during a pharmacological stress test; unstable angina requiring rehospitalisation; or a new myocardial infarction.
Experimental Group: (n = 1114, 1114 analysed): early invasive therapy: coronary angiography 4-48 hours after randomisation, with angioplasty and stenting as required
All patients received 325 mg aspirin, iv unfractionated heparin (5000 unit bolus, followed by 1000 units/hour for 48 hours) and tirofiban (loading dose 0.4 microgm/kg/min for 30 min, followed by 0.1 microg/kg/min for 48 hours or until 12 hours after revascularisation). Patients could also receive beta-blockers, nitrates, and lipid-lowering therapy.
99% followed for 6 months

The evidence

Outcome Time to outcome CER EER RRR
(95% CI)		 ARR
(95% CI)		 NNT
(95% CI)
coronary angiography 6 months 672
(60.8%)		 1087
(97.6%)		 61%
(53% to 69%)		 36.8%
(33.8% to 39.8%)		 3
(3 to 3)
coronary angioplasty 6 months 323
(29.2%)		 472
(42.4%)		 45%
(29% to 63%)		 13.2%
(9.22% to 17.1%)		 8
(6 to 11)
CABG 6 months 178
(16.1%)		 243
(21.8%)		 36%
(14% to 61%)		 5.72%
(2.47% to 8.97%)		 17
(11 to 41)
death, myocardial infarction or rehospitalisation with an acute coronary syndrome 6 months 215
(19.4%)		 177
(15.9%)		 18%
(2% to 32%)		 3.55%
(0.38% to 6.72%)		 28
(15 to 260)
any myocardial infarction 6 months 76
(6.87%)		 53
(4.76%)		 31%
(3% to 51%)		 2.11%
(0.17% to 4.06%)		 47
(25 to 590)

Comments

  1. Patients in the invasive strategy group spent one day shorter in hospital (5 days v. 6 days: p < 0.001).

Citation

  1. Cannon CP, Weintraub WS, Demopoulos LA, et al: comparison of early invasive and conservative strategies in patients with unstable coronary syndromes treated with the glycoprotein IIb/IIIa inhibitor tirofiban (TACTICS-TIMI 18). New Engl J Med 2001; 344 : 1879-1887
Search Terms: from ACP Journal Club
Contributor: Chris Ball, March 2002
Reviewer:

Clinical Question.
Patient acute coronary syndrome
Intervention or Exposure early angiography and revascularisation
Comparison medical therapy and revascularisation if required
Outcome death, myocardial infarction, readmission with acute coronary syndrome