Objective: To characterise the comparative potency of optically pure (R)- and (S)-verapamil as regards negative dromotropic effects on atrioventricular (AV) node conduction and to compare the hemodynamic effects of single doses of the enantiomers in healthy volunteers.
Methods: Eight healthy volunteers received a single oral dose of 120 mg (S)-verapamil, 480 mg (R)-verapamil, 240 mg racemic verapamil (rac-verapamil) or placebo on 4 separate occasions. Serum concentrations of (R)- and (S)-verapamil were measured up to 24 h. Cardiovascular effects were assessed by electrocardiography, measurement of blood pressure and transthoracic impedance cardiography (cardiac output and total peripheral resistance). The comparative potency of (R)- and (S)-verapamil with regard to prolongation of the PR interval in the surface ECG was estimated by use of the areas under the effect-time and serum concentration-time curves and linear regression analyses of per cent change in PR interval from baseline versus the logarithm of serum (R)- or (S)-verapamil concentration.
Results: The PR interval was significantly prolonged after all verapamil treatments as compared with placebo. (S)-verapamil was 20.6-21.8 times more potent than (R)-verapamil with regard to negative dromotropic effects. (R)-verapamil caused a significantly greater maximum reduction in the mean arterial pressure (MAP) than placebo [15.9+/-6.8 versus 8.7+/-3.2 mmHg (mean+/-SD); 95% CI on the difference, 0.79-13.7 mmHg; p<0.05], whereas MAP was not affected by the other verapamil treatments. No significant changes were observed in heart rate, cardiac output and total peripheral resistance after any verapamil treatment as compared with placebo.
Conclusions: (S)-verapamil was about 20 times more potent than (R)-verapamil with regard to negative dromotropic effects on AV node conduction. (R)-verapamil but not (S)-verapamil significantly reduced the MAP as compared with placebo.
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http://dx.doi.org/10.1007/s00228-006-0154-7 | DOI Listing |
Medicine (Baltimore)
January 2025
Department of Cardiovascular Surgery, Eskisehir Osmangazi University Medical Faculty, Eskişehir, Türkiye.
This study assesses the effect of carotid sinus blockade applied with a local anesthetic on hemodynamic parameters during carotid endarterectomy (CEA) operations performed under general anesthesia. The medical records of patients who underwent CEA under general anesthesia between January 2020 and December 2022, were retrospectively reviewed. It was recorded whether the patients received carotid sinus block with 2 mL of 2% prilocaine.
View Article and Find Full Text PDFPLoS Med
January 2025
Institute for Global Health, University College London, London, United Kingdom.
Background: Cardiovascular disease (CVD) morbidity and mortality is increasing in Africa, largely due to undiagnosed and untreated hypertension. Approaches that leverage existing primary health systems could improve hypertension treatment and reduce CVD, but cost-effectiveness is unknown. We evaluated the cost-effectiveness of population-level hypertension screening and implementation of chronic care clinics across eastern, southern, central, and western Africa.
View Article and Find Full Text PDFPLoS One
January 2025
Equity Research and Innovation Center, Section of General Internal Medicine, Yale School of Medicine, New Haven, Connecticut, United States of America.
Background: Accurate assessment of cardiovascular disease (CVD) risk is crucial for effective prevention and resource allocation. However, few CVD risk estimation tools consider social determinants of health (SDoH), despite their known impact on CVD risk. We aimed to estimate 10-year CVD risk in the Eastern Caribbean Health Outcomes Research Network Cohort Study (ECS) across multiple risk estimation instruments and assess the association between SDoH and CVD risk.
View Article and Find Full Text PDFPLoS One
January 2025
Nursing & Midwifery Research Department (NMRD), Hamad Medical Corporation, Doha, Qatar.
Background: Ischemic heart disease (IHD) has a significant impact on public health and healthcare expenditures in the United States (US).
Methods: We used data from the CDC WONDER database from 1999-2020 to identify trends in the IHD-related mortality of patients ≥ 75 years in the US. AAMRs per 100,000 population and APC were calculated and categorized by year, sex, race, and geographic divisions.
PLoS One
January 2025
Department of General Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China.
Background: Glyphosate, as the main component of glyphosate pesticides, has been shown to have toxic effects on multiple human systems. However, the association between glyphosate and atherosclerotic cardiovascular disease (ASCVD) remains unclear. This study aims to explore the effect of glyphosate exposure on ASCVD.
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