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Updated: Jul 31, 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

Experimental antifibrillatory effects of calcium channel blockade with diltiazem: comparison with beta-blockade and

M Anastasiou-Nana, J Nanas, R L Menlove

    Journal of Cardiovascular Pharmacology
    |September 1, 1984
    PubMed

    Insights

    Beta-blockade (timolol) significantly increased ventricular fibrillation thresholds more than calcium channel blockade (diltiazem) in dogs. Nitroglycerin had no effect, highlighting the need for clinical trials on mortality reduction in ischemic heart disease.

    Area of Science:

    • Cardiology
    • Pharmacology

    Background:

    • Calcium channel blockers and beta-blockers are used for angina.
    • Their effectiveness against sudden cardiac death remains unclear.

    Purpose of the Study:

    • To compare the antifibrillatory effects of diltiazem, timolol, and nitroglycerin.
    • To assess their impact on ventricular fibrillation thresholds during ischemia.

    Main Methods:

    • Anesthetized dogs underwent coronary ischemia.
    • Ventricular fibrillation thresholds were measured before and after drug administration (diltiazem, timolol, nitroglycerin, or saline).

    Main Results:

    • Timolol significantly increased ventricular fibrillation thresholds under both ischemic and non-ischemic conditions.
    • Diltiazem also increased thresholds, but to a lesser extent than timolol.
    • Nitroglycerin did not alter ventricular fibrillation thresholds.

    Conclusions:

    • Beta-blockade (timolol) demonstrated stronger antifibrillatory effects than calcium channel blockade (diltiazem) in this experimental model.
    • Further clinical studies are required to determine the comparative efficacy of these agents in reducing mortality in ischemic heart disease.

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