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Intracoronary Acetylcholine Provocation Testing for Assessment of Coronary Vasomotor Disorders
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Adenosine causes transient dilatation of coronary arteries in man

A H Watt1, W J Penny, H Singh

  • 1Department of Pharmacology, University of Wales College of Medicine, Heath Park, Cardiff.

British Journal of Clinical Pharmacology
|November 1, 1987
PubMed

Insights

Intravenous adenosine administration temporarily doubled coronary blood flow in healthy individuals. This study provides direct evidence that adenosine dilates coronary arteries in humans, suggesting its use in assessing coronary flow reserve.

Area of Science:

  • Cardiovascular Physiology
  • Pharmacology

Background:

  • Coronary blood flow regulation is crucial for myocardial oxygen supply.
  • Adenosine's role in human coronary vasodilation requires direct investigation.

Purpose of the Study:

  • To investigate the effects of intravenous adenosine on coronary blood flow in humans.
  • To determine if adenosine causes coronary vasodilation.

Main Methods:

  • Ten healthy subjects undergoing chest pain evaluation were studied.
  • Intravenous adenosine was administered at a constant, paced heart rate.
  • Coronary blood flow was measured before and after adenosine infusion.

Main Results:

  • Intravenous adenosine administration resulted in a transient doubling of coronary blood flow.
  • This effect occurred without significant changes in perfusion pressure, systolic load, or inotropic state.
  • The observed vasodilation was dose-dependent, with effects seen at doses >= 3.5 mg.

Conclusions:

  • Adenosine directly dilates human coronary arteries.
  • The transient nature of adenosine-induced vasodilation suggests its potential utility in serial assessments of coronary flow reserve.

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