New drug discovery of cardiac anti-arrhythmic drugs: insights in animal models

Cardiac rhythm regulated by micro-macroscopic structures of heart. Pacemaker abnormalities or disruptions in electrical conduction, lead to arrhythmic disorders may be benign, typical, threatening, ultimately fatal, occurs in clinical practice, patients on digitalis, anaesthesia or acute myocardial infarction. Both traditional and genetic animal models are: In-vitro: Isolated ventricular Myocytes, Guinea pig papillary muscles, Patch-Clamp Experiments, Porcine Atrial Myocytes, Guinea pig ventricular myocytes, Guinea pig papillary muscle: action potential and refractory period, Langendorff technique, Arrhythmia by acetylcholine or potassium. Acquired arrhythmia disorders: Transverse Aortic Constriction, Myocardial Ischemia, Complete Heart Block and AV Node Ablation, Chronic Tachypacing, Inflammation, Metabolic and Drug-Induced Arrhythmia. In-Vivo: Chemically induced arrhythmia: Aconitine antagonism, Digoxin-induced arrhythmia, Strophanthin/ouabain-induced arrhythmia, Adrenaline-induced arrhythmia, and Calcium-induced arrhythmia. Electrically induced arrhythmia: Ventricular fibrillation electrical threshold, Arrhythmia through programmed electrical stimulation, sudden coronary death in dogs, Exercise ventricular fibrillation. Genetic Arrhythmia: Channelopathies, Calcium Release Deficiency Syndrome, Long QT Syndrome, Short QT Syndrome, Brugada Syndrome. Genetic with Structural Heart Disease: Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia, Dilated Cardiomyopathy, Hypertrophic Cardiomyopathy, Atrial Fibrillation, Sick Sinus Syndrome, Atrioventricular Block, Preexcitation Syndrome. Arrhythmia in Pluripotent Stem Cell Cardiomyocytes. Conclusion: Both traditional and genetic, experimental models of cardiac arrhythmias' characteristics and significance help in development of new antiarrhythmic drugs.

Neuropathic pain at diagnosis of head and neck squamous cell carcinoma

OBJECTIVE

To assess the prevalence and characteristics of neuropathic pain (NP) at diagnosis of head and neck squamous cell carcinoma (HNSCC) and its impact on nutritional status and treatment tolerance.

MATERIALS AND METHODS

Patients treated for HNSCC between January 1, 2018 and January 30, 2019 were included. Pain was assessed prospectively on the DN2 and NSPI scales. Epidemiological characteristics, nutritional status and treatment tolerance were collected. Two groups were distinguished according to absence or presence of neuropathic pain (NP-, NP+).

RESULTS

Sixty patients were included. NP prevalence at diagnosis was 54%, mainly involving locally advanced oral cavity and oropharyngeal tumors. There was a significant intergroup difference in nutritional status, with 62% malnutrition in NP+ versus 32% in NP- (p=0.0321). There was no such difference in tolerance.

CONCLUSION

NP is frequent at diagnosis of HNSCC. Early diagnosis on a simple validated score can help improve quality of life and nutritional status.

P4660Lipoprotein particle profiles compared with standard lipids in the association with sub-clinical aortic valve calcification in apparently healthy Japanese men

Introduction

Calcific aortic valve disease (CAVD) is one of the most common heart diseases worldwide, and its prevalence has increased in developed countries along with aging populations. Subclinical CAVD is characterized by aortic valve calcification (AVC) that may lead to aortic stenosis. AVC shares the same risk factors with atherosclerotic disease. Recently, nuclear magnetic resonance (NMR)-based lipoprotein particles, low-density and high-density lipoprotein particles (LDL-p, HDL-p) in particular, have emerged as novel markers of atherosclerotic disease. It has been unclear, however, whether NMR-based particles are associated with AVC.

Purpose

To examine cross-sectional association of NMR-based lipoprotein particles, standard lipids with AVC, and compare their strengths of association.

Methods

We studied a community-based random sample of Japanese men aged 40–79 years examined in 2006–08 in Japan. We excluded participants with history of myocardial infarction, stroke, aortic valve surgery, serum triglyceride concentration ≥400 mg/dl, estimated glomerular filtration rate (eGFR) <30 (ml/min/1.73m2), and use of lipid-lowering medication. We scored the degree of AVC according to Agatston's method, and defined prevalent AVC as the score >0. Lipoprotein particles were measured using NMR spectroscopy.

In our main analysis, we obtained multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (95% CI) of prevalent AVC in the top quartile (Q4) for each lipid index in reference to the lowest quartile (Q1). Adjusting covariates include age, smoking, drinking, systolic blood pressure, glycated hemoglobin, medications for hypertension and/or for diabetes, eGFR, C-reactive protein. For sensitivity analysis, we repeated similar analyses presenting ORs per 1 standard deviation (SD) higher NMR-lipoproteins particles or standard lipids.

Results

Of 874 participants we analyzed, 153 (17.5%) men had AVC. The average (SD) age was 63.3 (10.0) years. Those with AVC tended to be older, likely to have clustering of atherosclerotic risk factors. Multivariable-adjusted ORs of prevalent AVC for Q4 versus Q1 were significantly positive for LDL-p [OR, 2.21 (95% CI: 1.24, 3.95] and low-density lipoprotein cholesterol (LDL-c) [2.17 (1.24, 3.80)]. In contrast, neither HDL-p nor high-density lipoprotein cholesterol (HDL-c) was significantly associated with AVC. In sensitivity analyses, however, the corresponding ORs per 1SD higher lipids/lipoprotein particles were smaller in LDL-p [1.33 (1.09, 1.63)] than LDL-c [1.41 (1.15, 1.73)]. The association of HDL-p became significant [1.28 (1.02, 1.61)] (per 1SD decrement) in the sensitivity analysis.

Conclusion

The overall associations of AVC with NMR-based lipoprotein particles (i.e. LDL-p, HDL-p) are comparable to those of standard lipids. This finding is parallel to the association between atherosclerotic cardiovascular diseases with NMR-based lipoproteins.

Plasma lipid abnormalities in Pakistani population: trends, associated factors, and clinical implications

Previous studies have reported increased prevalence of coronary heart disease (CHD) in Indians and South Asian settlers in North America. This increased burden of CHD among South Asians is mainly caused by dyslipidemia. To the best of our knowledge, none of the previous works has studied the patterns and prevalence of dyslipidemia in the Pakistani population. The present work aimed to study the plasma lipid trends and abnormalities in a population-based sample of urban and rural Pakistanis. The study included 238 participants (108 males,130 females). Plasma lipid profiles of the participants were determined using standard protocols. We observed that 63% of the study population displayed irregularities in at least one major lipid-fraction including total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), or triglycerides (TG). The most common form of isolated-dyslipidemia was low HDL-C (17.3%) followed by high TG (11.2%). Several overlaps between high TC, LDL-C, TG and low HDL-C were also noted. Gender, urbanization, and occupational class were all observed to have an impact on lipid profiles. Briefly, male, urban, and blue-collar participants displayed higher prevalence of dyslipidemia compared to female, rural, and white-collar participants, respectively. In comparison to normal subjects, dyslipidemic subjects displayed significantly higher values for different anthropometric variables including body mass index (BMI), body fat percentage, and waist circumference. The present work provides a comprehensive estimation of the prevalence of dyslipidemia and CHD risk in the Pakistani population. This information will be helpful for better healthcare planning and resource allocation in Pakistan.