Effects of the T-type calcium channel blockade with oral mibefradil on the electrophysiologic properties of the human heart
Alois Madle, Katerina Linhartova, Jiri KozaMed Sci Monit 2001; 7(1): CR74-77 :: ID: 510908
Abstract
Background: As the calcium T-channel blockade is a new pharmacological category with presumably unique electrophysiological effects, the influence of its only representative yet mibefradil was tested after the single oral dose.
Material/Methods: 10 patients underwent the electrophysiologic examination. Normal baseline values in sinus node cycle length (SNCL), sinus node recovery time (SNRT), corrected sinus node recovery time (CSNRT), PA interval, atrial effective refractory period, AH interval, Wenckebach point (WP), atrioventricular nodal refractory period, and HV interval were measured using standard techniques. After that a single dose of 100 mg mibefradil was given and the testing repeated in 90 minutes.
Results: Though non-significantly in a study-group limited in size due to global withdrawal of mibefradil, sinus node automaticity was suppressed (prolongation of SNRT by 5.1% and CSNRT by 11.5%) and heart rate lowered (SNCL prolonged by 2.8%) comparatively more than was the negative dromotropic effect on the atrioventricular node (negligible prolongation of AH interval by 1.1% and WP cycle by 0.4%).
Conclusions: Demonstrated electrophysiological effects of oral mibefradil with more pronounced influence on the automaticity of the sinus node seem to be in agreement with the preclinical data on the predominant role of T-channels in the pacemaker activity of the sinus node. According to the Framingham data on the risk of heart rate for the cardiovascular as well as all-cause mortality, calciumT-channel blockade offers a desirable profile for antihypertensive treatment. From this point of view development of new representatives of calcium T-channel blockers could be a useful contribution to clinical practice.
Keywords: calcium antagonist, T-channel calcium blocker, Mibefradil, Electrophysiology, Sinus node, Atrioventricular Node
750 13
Editorial
01 December 2023 : Editorial
Editorial: Outbreaks of Post-Pandemic Childhood Pneumonia and the Re-Emergence of Endemic Respiratory InfectionsDOI: 10.12659/MSM.943312
Med Sci Monit 2023; 29:e943312
In Press
08 Dec 2023 : Clinical Research
Association Between Influenza Vaccine Uptake and Health Awareness: A Cross-Sectional Questionnaire-Based St...Med Sci Monit In Press; DOI:
04 Dec 2023 : Animal Research
Effects of Intrathecal Ketamine on Cerebrospinal Fluid Levels of Brain-Derived Neurotrophic Factor and Mech...Med Sci Monit In Press; DOI:
01 Dec 2023 : Clinical Research
Risk Factors and Clinical Outcomes of COVID-19 Infection in Multiple Sclerosis Patients: A Retrospective St...Med Sci Monit In Press; DOI:
30 Nov 2023 : Review article
Decoding the Neurological Sequelae of General Anesthesia: A ReviewMed Sci Monit In Press; DOI:
Most Viewed Current Articles
13 Nov 2021 : Clinical Research
Acceptance of COVID-19 Vaccination and Its Associated Factors Among Cancer Patients Attending the Oncology ...DOI :10.12659/MSM.932788
Med Sci Monit 2021; 27:e932788
30 Dec 2021 : Clinical Research
Retrospective Study of Outcomes and Hospitalization Rates of Patients in Italy with a Confirmed Diagnosis o...DOI :10.12659/MSM.935379
Med Sci Monit 2021; 27:e935379
14 Dec 2022 : Clinical Research
Prevalence and Variability of Allergen-Specific Immunoglobulin E in Patients with Elevated Tryptase LevelsDOI :10.12659/MSM.937990
Med Sci Monit 2022; 28:e937990
08 Mar 2022 : Review article
A Review of the Potential Roles of Antioxidant and Anti-Inflammatory Pharmacological Approaches for the Man...DOI :10.12659/MSM.936292
Med Sci Monit 2022; 28:e936292