Effects of percutaneous coronary interventions in silent ischemia after myocardial infarction: the SWISSI II randomized controlled trial

JAMA. 2007 May 9;297(18):1985-91. doi: 10.1001/jama.297.18.1985.


Context: The effect of a percutaneous coronary intervention (PCI) on the long-term prognosis of patients with silent ischemia after a myocardial infarction (MI) is not known.

Objective: To determine whether PCI compared with drug therapy improves long-term outcome of asymptomatic patients with silent ischemia after an MI.

Design, setting, and participants: Randomized, unblinded, controlled trial (Swiss Interventional Study on Silent Ischemia Type II [SWISSI II]) conducted from May 2, 1991, to February 25, 1997, at 3 public hospitals in Switzerland of 201 patients with a recent MI, silent myocardial ischemia verified by stress imaging, and 1- or 2-vessel coronary artery disease. Follow-up ended on May 23, 2006.

Interventions: Percutaneous coronary intervention aimed at full revascularization (n = 96) or intensive anti-ischemic drug therapy (n = 105). All patients received 100 mg/d of aspirin and a statin.

Main outcome measures: Survival free of major adverse cardiac events defined as cardiac death, nonfatal MI, and/or symptom-driven revascularization. Secondary measures included exercise-induced ischemia and resting left ventricular ejection fraction during follow-up.

Results: During a mean (SD) follow-up of 10.2 (2.6) years, 27 major adverse cardiac events occurred in the PCI group and 67 events occurred in the anti-ischemic drug therapy group (adjusted hazard ratio, 0.33; 95% confidence interval, 0.20-0.55; P<.001), which corresponds to an absolute event reduction of 6.3% per year (95% confidence interval, 3.7%-8.9%; P<.001). Patients in the PCI group had lower rates of ischemia (11.6% vs 28.9% in patients in the drug therapy group at final follow-up; P = .03) despite fewer drugs. Left ventricular ejection fraction remained preserved in PCI patients (mean [SD] of 53.9% [9.9%] at baseline to 55.6% [8.1%] at final follow-up) and decreased significantly (P<.001) in drug therapy patients (mean [SD] of 59.7% [11.8%] at baseline to 48.8% [7.9%] at final follow-up).

Conclusion: Among patients with recent MI, silent myocardial ischemia verified by stress imaging, and 1- or 2-vessel coronary artery disease, PCI compared with anti-ischemic drug therapy reduced the long-term risk of major cardiac events.

Trial registration: clinicaltrials.gov Identifier: NCT00387231.

Publication types

  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angioplasty, Balloon, Coronary*
  • Coronary Artery Disease / therapy
  • Echocardiography, Stress
  • Female
  • Humans
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors / therapeutic use
  • Kaplan-Meier Estimate
  • Male
  • Middle Aged
  • Myocardial Infarction / therapy
  • Myocardial Ischemia / diagnosis
  • Myocardial Ischemia / therapy*
  • Platelet Aggregation Inhibitors / therapeutic use
  • Prognosis
  • Proportional Hazards Models
  • Radionuclide Angiography
  • Vasodilator Agents / therapeutic use


  • Hydroxymethylglutaryl-CoA Reductase Inhibitors
  • Platelet Aggregation Inhibitors
  • Vasodilator Agents

Associated data

  • ClinicalTrials.gov/NCT00387231