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Long QT syndrome (LQTS) is one of the most common inherited cardiac channelopathies with a prevalence of 1:2000. The condition can be congenital or acquired with 15 recognized genotypes; the most common subtypes are LQTS 1, 2, and 3 making up to 85%-90% of the cases. LQTS is characterized by delayed ventricular cardiomyocyte repolarization manifesting on the surface electrocardiogram (EKG) by a prolonged corrected QT (QTc) interval. The mainstay of treatment for this condition involves in part or combination medical therapy via β-blockers as first-line (or other anti-arrhythmic), left cardiac sympathectomy, or implantable cardiac defibrillator placement. Given the high rate of adverse cardiac events (ACE) or sudden cardiac death (SCD) in this population of patients with this disease, this review seeks to highlight the genotype-specific treatment consensus in β-blocker therapy of the most common subtypes. A database search of PubMed, PMC, and Medline was conducted to ascertain the most recent data in the last five years on the management of LQTS types 1-3 and the role of β-blockers in reducing ACE in these types. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were adhered to in the study selection, and selected studies focused on humans, written in the English Language, and within the last five years of LQTS subtypes 1, 2, and 3. Eleven relevant studies were selected after considering inclusion criteria, exclusion criteria, and quality appraisal within the last five years, focusing on β-blocker selection directed based on the subtypes of LQTS. Two meta-analyses, one cohort study, and eight reviews provided significant data that non-selective β-blockers unequivocally are of benefit in these LQTS types. Summary of findings suggested nadolol followed by propranolol yields the best results in LQTS 1, while nadolol would yield the best effect in LQTS 2 and 3.

Reactivity to a reward is affected by prior experience with different reinforcer values of that reward, a phenomenon known as incentive relativity. Incentive relativity can be studied via the consummatory successive negative contrast (cSNC) paradigm, in which acceptance of 4% sucrose is assessed in animals that had been exposed to 32% sucrose. These downshifted animals usually exhibit significantly less sucrose acceptance than animals that always received the 4% sucrose solution. In previous work, we found that exploration of a novel open field (OF) before the first trial with the downshifted solution attenuated the contrast effect. The goal of the present experiments was to expand the knowledge on the effects of OF exposure on cSNC. We evaluated the effect OF exposure before the second downshift trial and assessed the mediational role of the adrenergic system in the effects of OF during the first and second trial of cSNC. The results indicate that OF applied before the first or second downshift trials exert opposite effects and that the adrenergic system is involved in the acquisition and consolidation of the OF information. Fil: Justel, Nadia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina Fil: Psyrdellis, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina Fil: Pautassi, Ricardo Marcos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina Fil: Mustaca, Alba Elisabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Universidad Abierta Interamericana; Argentina

Thyroidectomy is the most common endocrine surgical procedure being carried out throughout the world. Besides, many patients who have deranged thyroid physiology, namely hyperthyroidism and hypothyroidism, have to undergo various elective and emergency surgical procedures at some stage of their life. The attending anesthesiologist has to face numerous daunting tasks while administering anesthesia to such patients. The challenging scenarios can be encountered at any stage, be it preoperative, intra-op or postoperative period. Preoperatively, deranged thyroid physiology warrants optimal preparation, while anticipated difficult airway due to enlarged thyroid gland further adds to the anesthetic challenges. Cardiac complications are equally challenging as also the presence of various co-morbidities which make the task of anesthesiologist extremely difficult. Thyroid storm can occur during intra-op and post-op period in inadequately prepared surgical patients. Postoperatively, numerous complications can develop that include hemorrhage, laryngeal edema, nerve palsies, tracheomalacia, hypocalcemic tetany, pneumothorax, etc., The present review aims at an in-depth analysis of potential risk factors and challenges during administration of anesthesia and possible complications in patients with thyroid disease.

Introduction: Several therapeutic approaches have been developed to treat choroidal hemangioma. However, all these therapies are associated with a potential risk of damaging the overlying retina. Case Report: We report a case of circumscribed choroidal hemangioma (CCH) in a 59-year-old man refractory to laser treatment. Visual acuity was 20/200 and a serous macular detachment was present. The CCH was treated with oral propanolol, whereupon visual acuity improved to 20/20 and the macular detachment resolved without systemic or local adverse effects. Discussion: Propanolol is a β-blocker commonly used in cardiology that may induce endothelium vasoconstriction and inhibit endothelial proliferation. It has been shown to be effective in infantile facial hemangiomas, and proved safe and effective for the CCH in our patient. Further studies are needed to confirm our observation.

Background: Ergometrine is a uterotonic agent that is recommended in the prevention and management of post partum hemorrhage. Despite its long-standing use the mechanism by which it acts in humans has never been fully elucidated. The objective of this study was to investigate the role of adrenoreceptors in ergometrine's mechanism of action in human myometrium. The study examined the hypothesis that alpha adrenoreceptor antagonism would result in the reversal of the uterotonic effects of ergometrine. Methods: Myometrial samples were obtained from women undergoing elective cesarean delivery. The samples were then dissected into strips and mounted in organ bath chambers. Following generation of an ergometrine concentration-response curve (10-15 to 10-5 M), strips were treated with increasing concentrations of ergometrine (10-15 to 10-7 M) alone and ergometrine (10-7 to 10-5 M) in the presence of phentolamine (10-7 M), prazosin (10-7 M), propranolol (10-6 M) or yohimbine (10-6 M). The effects of adding ergometrine and the effect of drug combinations were analysed using linear mixed effects models with measures of amplitude (g), frequency (contractions/10min) and motility index (g*contractions/10min). Results: A total of 157 experiments were completed on samples obtained from 33 women. There was a significant increase in the motility index (adding 0.342 g*counts/10min/µM; 95% CI from 0.253 to 0.431, P

The Brazilian Society of Cardiology (SBC) proposes that hypertensive subjects who use beta-blockers and practice physical exercises must have their training heart rate (HR) corrected due to the negative chronotropic effect of this drug. Nevertheless, if the physical activity is performed outside of plasmatic half-life, correction may not be necessary. This study investigated the exercise chronotropic response both inside and outside the beta-blocker plasmatic half-life. Nine subjects in use of atenolol or propranolol, and six controls, carried out three walking sessions in three days according to different schedules: EX2 (two hours after drug administration, at the plasmatic peak); EX11 (eleven hours after drug administration, at the end of plasmatic half-life); and EX23 (twenty-three hours after drug administration, outside the plasmatic half-life. The walking sessions were performed on an ergometric treadmill and HR was monitored by a heart rate monitor. During the exercises, mean HRs were 97.2, 108.4 and 109 for EX2, EX11 and EX23, respectively, with the value for EX2 statistically lower than the others (p0.05). The study concludes that the attenuation of the positive chronotropic response which occurs during exercise in subjects using beta-blockers, is less evident when the exercise is performed outside the plasmatic half-life of the drug.A Sociedade Brasileira de Cardiologia (SBC) propõe que os hipertensos que utilizam beta-bloqueadores e praticam exercícios físicos devem ter sua frequência cardíaca de treinamento (HR) corrigida devido ao efeito cronotrópico negativo desse fármaco. Contudo, se a atividade física é realizada fora da meia-vida plasmática do fármaco, a correção pode não ser necessária. Este estudo investigou a resposta cronotrópica ao exercício dentro e fora da meia-vida plasmática do beta-bloqueador. Nove indivíduos que usavam atenolol ou propranolol e seis controles, efetuaram três sessões de caminhada em três dias, de acordo com diferentes esquemas: EX2 (duas horas após a administração do fármaco, no pico plasmático); EX11 (11 horas após a administração do fármaco, no fim da meia-vida plasmática) e EX23 (23 horas após a administração do fármaco, fora da meia-vida plasmática). As caminhadas foram realizadas em esteira ergométrica e a HR foi monitorada por monitor de freqüência cardíaca. Durante os exercícios, as HR médias foram de 97,2, 108,4 e 109, para EX2, EX11 e EX23, respectivamente, com valor de EX2 estatisticamente mais baixo do que os outros (p0,05). O estudo conclui que a atenuação da resposta cronotrópica positiva, que ocorre durante o exercício em indivíduos que utilizam beta-bloqueadores, é menos evidente quando o exercício é realizado fora da meia-vida plasmática do fármaco.

Hemangiomas are the most frequent vasculartumors observed in early childhood. Thepresentation is unique, with an initialphase of proliferation, followed by aphase of slow, spontaneous regression after the age of1 year.1,2 Most hemangiomas are uncomplicated anddo not require intervention. However, therapy may beneeded if the hemangioma is located at certain bodysites, such as the face, or if it results in a functionalhandicap, such as limitation of eye opening. Inaddition, ulcerated, rapidly growing hemangiomasmay require treatment.3

1. 1. Adrenalin (5.0 × 10-5M) increases gill vascular resistance up to 23.2 ± 6.8% in the isolated and perfused head of the european eel (Anguilla anguilla L.). 2. 2. This vasoactive response is nearly abolished by the α-adrenergic blocking agent phentolamine mesylate (5.0 × 10-4M), while it is increased by the β-blocker propranolol (5.0 × 10-5M). 3. 3. From these results it may be inferred that, in our experimental conditions, the major response to the catecholamine is a vasoconstriction mediated via α-adrenoceptors. © 1983.