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AT1-receptor blockade with irbesartan improves peripheral but not coronary endothelial dysfunction in patients with

Ascan Warnholtz1, Mir Abolfazl Ostad, Thomas Heitzer

  • 1Department of Medicine II, Johannes Gutenberg-University Mainz, Langenbeckstrasse 1, 55101 Mainz, Germany. warnholt@uni-mainz.de

Atherosclerosis
|September 15, 2006
PubMed

Insights

Irbesartan improved peripheral endothelial function in coronary artery disease (CAD) patients, but did not affect coronary function. This improvement in brachial artery flow-dependent dilation (FMD) may enhance prognosis for CAD patients.

Area of Science:

  • Cardiovascular Medicine
  • Pharmacology

Background:

  • The renin-angiotensin-aldosterone system is implicated in endothelial dysfunction and atherosclerosis.
  • Previous studies on AT1-receptor blockers' effects on endothelial dysfunction in coronary artery disease (CAD) yielded inconsistent results.
  • Limited research exists on the dual effects of AT1-receptor blockers on both coronary and peripheral function within the same patient cohort.

Purpose of the Study:

  • To investigate the impact of long-term irbesartan therapy on both coronary and peripheral endothelial function in patients with CAD.
  • To assess whether irbesartan influences markers like N(G),N(G)-dimethyl-arginine and isoprostane excretion rates.

Main Methods:

  • A 6-month double-blind, placebo-controlled study involving 72 CAD patients.
  • Random assignment to irbesartan (300 mg/day) or placebo.
  • Assessment of coronary endothelial function via intracoronary acetylcholine infusion and peripheral endothelial function using brachial artery flow-dependent dilation (FMD).

Main Results:

  • Irbesartan significantly improved peripheral endothelial function, as measured by FMD.
  • No significant changes were observed in coronary endothelial function.
  • Plasma levels of N(G),N(G)-dimethyl-arginine and isoprostane excretion rates remained unchanged.

Conclusions:

  • Long-term irbesartan therapy benefits peripheral endothelial function in CAD patients.
  • Irbesartan does not improve coronary endothelial function in this population.
  • The observed improvement in FMD suggests a potential for better cardiovascular outcomes in CAD patients treated with irbesartan.

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