Trial Details:

Acronym: Invasive versus Conservative Treatment in Unstable Coronary Syndromes Trial

Purpose: To determine if an early invasive stategy (using coronary angiography and PCI) should be used in all non-ST elevation MI patients or to determine which subgroups benefit from this approach.

Format: Double blind, multicenter, randomized controlled trial

Treatment Group: Early invasive strategy (coronary angiography)

Control Group: Inital conservative strategy (medical therapy followed by risk stratification)

Number of Patients: 1,200

Inclusion Criteria:

  • Symptoms of ischemia that were increasing or occuring at rest
  • Last episode of angina no more than 24 hours prior
  • Elevated cardiac troponin T of at least 0.03 μg per liter
  • One of the following must also be present
    • Ischemic changes on ECG - ST depression 
    • Transient ST elevation of no more than 0.5 mm 
    • T wave inversion in two contiguous leadsd
    • Documented history of coronary artery disease such as prior MI or seen on previous coronary angiography
    • Positive exercise test

Exclusion Criteria:

  • Age < 18 or > 80
  • MI with ST eleation in past 48 hours
  • Any indication for primary PCI or thrombolytic therapy
  • Hemodynamic instability
  • Overt congestive heart failure
  • Use of oral anticoagulants in past 7 days
  • PCI within 14 days
  • Contraindication to using glycoprotein IIb/IIIa inhibitors
  • Recent trauma or risk of bleeding
  • Hypertension despite treatment (systolic BP > 180/100 mmHg)
  • Weight > 120 kg
  • Inability to give informed consent

Follow-up: 1 year

Primary Endpoint: Composite of death, recurrent myocardial infarction, or rehospitalization for angina at 1 year

Secondary Endpoint: 

  • Major bleeding
  • Presence of recurrent angina


Evaluated early invasive versus initial conservative therapy in patients with non-ST segment elevation myocardial infarction (NSTEMI). The primary composite endpoint of all-cause mortality, nonfatal MI or rehospitalization for anginal symptoms within one year was no different between the two groups.

Original Publication:

deWinter RJ, et al. N Engl J Med. 2005;doi:10.1056/NEJMoa044259.