Evidence of ischemic preconditioning in patients experiencing first non-ST-segment elevation myocardial infarction (NSTEMI)

Int J Cardiol. 2003 Dec;92(2-3):209-17. doi: 10.1016/s0167-5273(03)00087-1.

Abstract

Background: Several studies have demonstrated the protective effects of preinfarction angina in Q wave myocardial infarction, implicating the role of ischemic preconditioning but this role remains uncertain in patients with a NSTEMI. Subendocardial viability in NSTEMI patients, is thought to be less dependent on collateral circulation and thus more likely to be protected by other mechanisms such as preconditioning.

Methods: We have studied prospectively 40 patients with first NSTEMI and with angiographically proven poor or no collateral development and compared two groups; those with versus those without preinfarction angina. All in-hospital events, such as recurrent angina, congestive heart failure, arrhythmias and reinfarction were recorded. Serum markers of myocardial necrosis (CPK, CPK-MB, AST) and discharge QTc values were estimated.

Results: Preconditioned patients suffered less recurrent angina (18 vs. 55% P=0.014), congestive heart failure (0 vs. 22%, P=0.02), arrhythmic events (0 vs. 27%, P=0.008) and had significant smaller values of mean peak CPK (381 +/- 152 vs. 859 +/- 496 I.U./l, P=0.0008), mean peak CPK-MB (45.5 +/- 24.6 vs. 105.2 +/- 87 I.U./l, P=0.01), mean peak AST (59.8 +/- 23.1 vs. 112.4 +/- 64.3 I.U./l, P=0.003) and QTc value at discharge (0.42 +/- 0.03 vs. 0.46 +/- 0.05 s, P=0.005) than patients without preconditioning. Multiple logistic regression analysis confirmed that the absence of preinfarction angina (relative risk 9.10, 95% CI 2.08-40.00, P=0.003) was a significant predictor of in-hospital complications.

Conclusions: Preinfarction angina constitutes a strong clinical correlate to ischemic preconditioning in patients with first NSTEMI, offering serious protection, by improving in-hospital outcome and reducing infarct size.

MeSH terms

  • Angina Pectoris / diagnosis
  • Angina Pectoris / physiopathology*
  • Case-Control Studies
  • Collateral Circulation / physiology
  • Coronary Circulation / physiology
  • Electrocardiography
  • Female
  • Humans
  • Ischemic Preconditioning, Myocardial*
  • Logistic Models
  • Male
  • Middle Aged
  • Myocardial Infarction / physiopathology*
  • Outcome Assessment, Health Care
  • Prospective Studies
  • Risk Factors