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Updated: Aug 10, 2026

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents
10:53

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents

Published on: July 3, 2013

Effects of calcium entry blockade on myocardial blood flow

R J Bache1

  • 1Department of Medicine, University of Minnesota, Minneapolis 55455.

Circulation
|December 1, 1989
PubMed

Insights

Calcium entry blockers aid anti-ischemia by preventing coronary artery vasoconstriction and enhancing blood flow to the subendocardium. Diltiazem specifically improves collateral blood flow in chronic coronary occlusion models.

Area of Science:

  • Cardiovascular Pharmacology
  • Ischemic Heart Disease

Background:

  • Calcium entry blockers impact coronary vasculature, suggesting anti-ischemia potential.
  • These drugs minimally affect basal epicardial arteries but counter vasoconstriction during exercise and spasm.

Purpose of the Study:

  • To evaluate the anti-ischemia effects of calcium entry blockers on coronary vasculature.
  • To understand their impact on coronary blood flow regulation and collateral circulation.

Main Methods:

  • Review of pharmacological effects on coronary arteries (epicardial and resistance vessels).
  • Analysis of impact on vasoconstriction, vasodilation, and reactive hyperemia.
  • Examination of effects on coronary collateral vessels in acute and chronic occlusion models.

Main Results:

  • Calcium blockers prevent vasoconstriction exacerbating stenosis and interrupt variant angina spasms.
  • They cause transient vasodilation of resistance vessels, reducing responsiveness to ischemia and reactive hyperemia.
  • These agents enhance subendocardial perfusion distal to stenoses by preventing excessive vasodilation.
  • Limited effect on acute collateral vessels, but diltiazem improves collateral flow in chronic occlusion models.

Conclusions:

  • Calcium entry blockers offer anti-ischemia benefits by modulating coronary vascular tone and improving perfusion.
  • Their differential effects on resistance vessels and collaterals highlight specific therapeutic applications in ischemic heart disease.

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