Ivabradine restores tonic cardiovascular autonomic control and reduces tachycardia, hypertension and left ventricular inflammation in post-weaning protein malnourished rats.

Malnutrition results in autonomic imbalance and heart hypertrophy. Overexpression of hyperpolarization-activated cyclic nucleotide-gated channels (HCN) in the left ventricles (LV) is linked to hypertrophied hearts and abnormal myocardium automaticity. Given that ivabradine (IVA) has emerging pleiotropic effects, in addition to the widely known bradycardic response, this study evaluated if IVA treatment could repair the autonomic control and cardiac damages in malnourished rats. AIM: Assess the impact of IVA on tonic cardiovascular autonomic control and its relationship with hemodynamics regulation, LV inflammation, and HCN gene expression in post-weaning protein malnutrition condition. MAIN METHODS: After weaning, male rats were divided into control (CG; 22 % protein) and malnourished (MG; 6 % protein) groups. At 35 days, groups were subdivided into CG-PBS, CG-IVA, MG-PBS and MG-IVA (PBS 1 ml/kg or IVA 1 mg/kg) received during 8 days. We performed jugular vein cannulation and electrode implant for drug delivery and ECG registration to assess tonic cardiovascular autonomic control; femoral cannulation for blood pressure (BP) and heart rate (HR) assessment; and LV collection to evaluate ventricular remodeling and HCN gene expression investigation. KEY FINDINGS: Malnutrition induced BP and HR increases, sympathetic system dominance, and LV remodeling without affecting HCN gene expression. IVA reversed the cardiovascular autonomic imbalance; prevented hypertension and tachycardia; and inhibited the LV inflammatory process and fiber thickening caused by malnutrition. SIGNIFICANCE: Our findings suggest that ivabradine protects against malnutrition-mediated cardiovascular damage. Moreover, our results propose these effects were not attributed to HCN expression changes, but rather to IVA pleiotropic effects on autonomic control and inflammation.

[Clinical characteristics of 42 children with focal atrial tachycardia originated from the right atrial appendage].

Objective: To investigate the feature and treatment of atrial tachycardia (AT) originated from right atrial appendage (RAA) in children. Methods: The data of 42 children with AT originated from RAA, who were admitted the First Hospital of Tsinghua University from January 2010 to September 2022 were analyzed retrospectively.The clinical characteristics, treatment and efficacy were analyzed. The children were divided into tachycardia cardiomyopathy group and normal cardiac function group. The differences in the ablation age and the heart rate during AT between two groups were compared by independent sample t-test. Results: Among 42 children, there were 20 males and 22 females. The age of onset was 2.7 (0.6, 5.1) years. Their age at radiofrequency ablation was (6.5±3.6) years, and the weight was (23.4±10.0) kg. Thirty-two children (76%) had sustained AT. The incidence of tachycardia cardiomyopathy was 43% (18/42). Compared to that of the normal cardiac function group, the ablation age and the heart rate at atrial tachycardia of the tachycardia cardiomyopathy group were higher ((8.1±3.8) vs. (5.3±3.1) years, t=-2.63, P=0.012; (173±41) vs. (150±30) beats per minute, t=-2.05, P=0.047. Thirty-eight children (90%) responded poorly to two or more antiarrhythmic drugs. The immediate success rate of radiofrequency ablation (RFCA) was 57% (24/42), and the AT recurrence rate was 17% (4/24). Twenty-two children underwent RAA resection, and their AT were all converted to sinus rhythm after the surgery. During the RAA resection, 10 cases of right atrial appendage aneurysm were found, 9/18 of which failed the RFCA. Conclusions: The AT originated from the RAA in children tend to present with sustained AT, respond poorly to antiarrhythmic drugs, and has a low success rate of RFCA as well as high recurrence rate. Resection of the RAA is a safe and effective complementary treatment.

Efficacy of a single dose of esmolol to prevent extubation-related complications during emergence from anesthesia: a randomized, double-blind, placebo-controlled trial

Abstract Background Few trials have examined the efficacy of esmolol to attenuate hemodynamic and respiratory responses during extubation. However, the most appropriate dose of esmolol and an optimal protocol for administering this beta-blocker are uncertain. Methods Ninety patients ASA physical status I, II, and III (aged 18-60 years) scheduled to procedures with general anesthesia and tracheal extubation were selected. Patients were randomized into esmolol and placebo group to evaluate the efficacy and safety of a single bolus dose of esmolol (2 mg.kg-1) on cardiorespiratory responses during the peri-extubation period. The primary outcome was the rate of tachycardia during extubation. Results The rate of tachycardia was significantly lower in esmolol-treated patients compared to placebo-treated patients (2.2% vs. 48.9%, relative risk (RR): 0.04, 95% confidence interval (95% CI) = 0.01 to 0.32, p= 0.002). The rate of hypertension was also significantly lower in the esmolol group (4.4% vs. 31.1%, RR: 0.14, 95% CI 0.03 to 0.6, p= 0.004). Esmolol-treated patients were associated with higher extubation quality compared to patients who received placebo (p< 0.001), with an approximately two-fold increase in the rate of patients without cough (91.1%) in the esmolol group compared to the placebo group (46.7%). The rate of bucking was approximately 5-fold lower in the esmolol group (8.9% vs. 44.5%, respectively, RR: 0.20 (95% CI, 0.1 to 0.5, p= 0.002, with an NNT of 2.8). Conclusion A single bolus dose of esmolol is an effective and safe therapeutic strategy to attenuate cardiorespiratory responses during the peri-extubation period.

Cryoablation as a first-line therapy for atrial fibrillation: current status and future prospects.

INTRODUCTION: Atrial fibrillation (AF) is a common chronic and progressive heart rhythm disorder. For those in whom sinus rhythm is desired, contemporary clinical practice guidelines recommend antiarrhythmic drugs (AADs) as the initial therapy. However, these medications have modest efficacy and are associated with significant adverse effects. AREAS COVERED: The current article reviews the evidence surrounding first-line catheter ablation, particularly the emerging evidence surrounding the use of cryoballoon ablation as a first-line therapy. The focus of the review is on the outcomes of arrhythmia freedom, quality of life, health-care utilization, and safety. In addition, the article will review novel cryoablation systems. EXPERT OPINION: Recent evidence suggests that cryoballoon ablation significantly improves arrhythmia outcomes (e.g. freedom from any atrial tachyarrhythmia or symptomatic atrial tachyarrhythmia, reduction in arrhythmia burden), patient-reported outcomes (e.g. symptoms and quality of life), and health-care resource utilization (e.g. hospitalization), without increasing the risk of adverse events. These findings are relevant to patients, providers, and health-care systems, as they help inform the decision-making regarding the initial choice of rhythm-control therapy in patients with treatment-naive AF.

Amiodarona: fortalezas y debilidades / Amiodarone strengths and weaknesses

Prescritos en la práctica clínica por su eficacia. En su inicio se utilizó para tratar la angina de pecho. hoy día es usado para el tratamiento de cualquier forma de taquicardia. Objetivo: Reconocer la prescripción de la Amiodarona y sus efectos adversos. Métodos: Se realizó una revisión descriptiva en las bases de datos de Lilacs donde se encontraron 18 artículos y en PubMed/Medline (Mesh) 206 artículos, de los cuales se le aplicaron los criterios de inclusión a 51 artículos. Conclusiones: La amiodarona es uno de los antiarrítmicos más utilizados para el tratamiento de las arritmias, su variedad de efectos adversos y toxicidad es conocida, por tanto, los pacientes en tratamiento ameritan un minucioso monitoreo(AU)

Introduction: Amiodarone is one of the most prescribed antiarrhythmic drugs in clinical practice due to its efficacy. Initially it was used to treat angina pectoris, however, today it is used to treat any form of tachycardia. Objective: To identify the prescription of amiodarone and its adverse effects. Methods: A descriptive review was carried out in Lilacs databases where 18 articles were found and in PubMed/Medline (Mesh) 206 articles were retrieved. The inclusion criteria were applied to 51 articles. Conclusions: Amiodarone is one of the most widely used antiarrhythmic drugs for the treatment of arrhythmias, its variety of adverse effects and toxicity is known, therefore, patients undergoing treatment justify careful monitoring(AU)

When Adenosine Does Not Work: Apparent and Real Adenosine-Resistant Tachycardia.

ABSTRACT: Supraventricular tachycardia (SVT) is the most common arrhythmia in the pediatric population. Adenosine is widely accepted as the first-line pharmacological treatment for hemodynamically stable SVT, constituting a class I recommendation in the 2020 American Heart Association guidelines for pediatric life support (2020 American Heart Association Guidelines for cardiopulmonary resuscitation and emergency cardiovascular care). As most pediatric SVTs are dependent on the atrioventricular node (AVN) for their propagation, and adenosine acts primarily on the AVN, adenosine will frequently terminate the arrhythmia. The term "adenosine failure" is often used to describe when its administration does not result in sustained termination of the tachycardia. Because of its very short half-life, there is confusion between improper delivery, failure to have any effect on the tachycardia, or transient termination. There are some pediatric SVTs, which are not AVN dependent, and which truly are refractory to adenosine. Simultaneous electrocardiogram recording during administration can provide important information to differentiate between adenosine resistance and transient adenosine effect, thus guiding further management.

Effects of lidocaine and esmolol on hemodynamic response to tracheal intubation: a randomized clinical trial.

INTRODUCTION AND OBJECTIVES: Although lidocaine is widely used to prevent cardiovascular changes resulting from laryngoscopy and orotracheal intubation, it is still unclear whether there are more efficacious drugs. This study aimed to compare the beta-blocker esmolol with lidocaine regarding the effects on hemodynamic response after orotracheal intubation. METHODS: The study has a prospective, randomized, double-blind, superiority design, and assessed 69 participants between 18 and 70 years of age, ASA I-II, scheduled for elective or emergency surgery under general anesthesia with orotracheal intubation. Participants were randomly allocated to receive 1.5 mg.kg-1 esmolol bolus followed by 0.1 mg.kg-1.min-1 esmolol infusion (n = 34) or 1.5 mg.kg-1 lidocaine bolus followed by 1.5 mg.kg-1.h-1 lidocaine infusion (n = 35). We recorded changes in heart rate, arterial blood pressure and incidence of adverse events. RESULTS: Post-intubation tachycardia episodes were significantly less frequent in the esmolol group (5.9% vs. 34.3%; Relative Risk (RR) 0.17; 95% Confidence Interval (95% CI) 0.04-0.71; Number Needed to Treat (NNT) 3.5; p = 0.015. After orotracheal intubation, mean heart rate was significantly lower in the esmolol group (74.5 vs. 84.5, p = 0.006). Similar results were observed in the subsequent 3 and 6 minutes (75.9 vs. 83.9, p = 0.023 and 74.6 vs. 83.0, p = 0.013, respectively). CONCLUSION: Esmolol was a safe and more effective intervention to reduce incidence of tachycardia and control heart rate immediately after tracheal intubation when compared to lidocaine.

Pharmacologic therapy for engraftment arrhythmia induced by transplantation of human cardiomyocytes.

Heart failure remains a significant cause of morbidity and mortality following myocardial infarction. Cardiac remuscularization with transplantation of human pluripotent stem cell-derived cardiomyocytes is a promising preclinical therapy to restore function. Recent large animal data, however, have revealed a significant risk of engraftment arrhythmia (EA). Although transient, the risk posed by EA presents a barrier to clinical translation. We hypothesized that clinically approved antiarrhythmic drugs can prevent EA-related mortality as well as suppress tachycardia and arrhythmia burden. This study uses a porcine model to provide proof-of-concept evidence that a combination of amiodarone and ivabradine can effectively suppress EA. None of the nine treated subjects experienced the primary endpoint of cardiac death, unstable EA, or heart failure compared with five out of eight (62.5%) in the control cohort (hazard ratio = 0.00; 95% confidence interval: 0-0.297; p = 0.002). Pharmacologic treatment of EA may be a viable strategy to improve safety and allow further clinical development of cardiac remuscularization therapy.

Comparison of intravenous magnesium sulphate and lidocaine for attenuation of cardiovascular response to laryngoscopy and endotracheal intubation in elective surgical patients at Zewditu Memorial Hospital Addis Ababa, Ethiopia.

BACKGROUND: Laryngoscopy and endotracheal intubation are essential components of general anesthesia. But it is always associated with side effects called reflex cardiovascular responses. Many methods have been identified to attenuate these responses like intravenous lidocaine, deep inhalational anesthesia, vasodilators, intravenous magnesium sulphate even though therapeutic superiority remains understudied. METHODS: An institutional-based cohort study on 112 adult patients aged between 18-60 years was applied. 37 patients in the non-exposed group (Group N), 37 in the lidocaine group (Group L), and 38 in magnesium sulphate (Group M) were included. The hemodynamic parameters like heart rate, systolic, diastolic and mean arterial blood pressure at various time points up to 7 minutes post-intubation were recorded and the effect of both drugs to reduce hemodynamic responses was compared. Parametric data were analyzed using ANOVA and nonparametric data using the Kuruska-Wallis H rank test. P-value < 0.05 considered statistically significant. RESULTS: In all three groups, there was a statistically significant rise in heart rate and blood pressure from baseline. There was a statistically significant difference in mean heart rate throughout study minutes among the groups (p<0.001). However, there was no statistically significant difference in mean heart rate between Groups M and L at all post-intubation time intervals. In blood pressure at all three parameters there was statistically significant difference among groups at all-time points except no difference at 7th minutes in DBP. There was significantly lower blood pressure in group M compared to both groups. CONCLUSION: In conclusion, prophylactic administration of magnesium sulphate and lidocaine was effective in attenuating hemodynamic responses to the stress effect of laryngoscopy and intubation. But based on our finding prophylaxis of magnesium sulphate is associated with a more favorable hemodynamic response.

Reconhecimento da paralisia periódica hipocalêmica tireotóxica na emergência: relato de caso e revisão da literatura / Recognizing thyrotoxic hypokalemic periodic paralysis on emergency settings: a case report and literature revie

A paralisia periódica hipocalêmica tireotóxica é uma complicação inusitada do hipertireoidismo, porém é considerada urgência endocrinológica e ainda frequentemente subdiagnosticada. Sua apresentação clínica consiste na tríade de défice de potássio, tireotoxicose e fraqueza muscular ­ sendo esse último sintoma comum em diversas patologias. Realizamos uma revisão bibliográfica e destacamos, por meio do relato de caso, a importância do diagnóstico precoce dessa doença, possibilitando uma evolução favorável ao paciente, independente de sua etnia, sexo ou região geográfica. Atentamos ainda ao tratamento da doença, que, apesar de sua simplicidade, acarreta muitos equívocos.

The thyrotoxic hypokalemic periodic paralysis is a rare complication of hyperthyroidism, but is considered an endocrinological urgency, and yet frequently underdiagnosed. Its clinical presentation consists of potassium deficit, thyrotoxicosis, and muscular weakness, with the latter symptom being very common in several pathologies. We performed a bibliographic review and highlight, through a case report, the importance of the early diagnosis of this disease to allow favorable progression to the patient, regardless of ethnicity, sex, or geographical region. We also reinforce the importance of the disease treatment which, despite its simplicity, leads to many mistakes.

«A case of a pharmacoresistant tachyarrhythmia associated with Arnold-Chiari malformation¼.

Introduction: Arnold-Chiari malformation is a group of congenital malformations of the hindbrain. Common symptoms include cephalgia, vestibular, cerebral and cochlear disorders We present a case of pharmacoresistant tachyarrhythmia associated with Arnold-Chiari malformation.Case Description: A 49-year-old female patient had an Arnold-Chiari malformation (ACM), syringomyelia, a retrocerebellar cyst and a 6 year history of tachyarrhythmia. Heart rhythm normalized after Chiari decompression.Conclusion: ACM can lead to heart rhythm disorders.

Right Atrial Appendage Aneurysm Resection to Cure Aneurysm-Related Atrial Tachyarrhythmia.

Congenital right atrial appendage aneurysm (RAAA) is an extremely rare malformation that can coexist with atrial tachyarrhythmia. There is no consensus on treatment for this condition. This research aimed to investigate the clinical characteristics and efficacy of surgical resection to treat atrial tachyarrhythmia originating from RAAA in children. Four RAAA children diagnosed with atrial tachyarrhythmia at the age of 1-5.25 years weighing 8.3-17.1 kg were discussed in this retrospective study. Patients underwent various treatments, included electrocardiogram (ECG) and echocardiography, antiarrhythmic medication therapy, radiofrequency catheter ablation (RFCA), surgical resection of RAAA and pathological examinations. The results from these treatments along with clinical features of patients were analyzed. The incidence of RAAA in patients with atrial tachycardia originating from the right or left atrial appendages (RAA or LAA) was 7.3% (4/55). The prevalence of RAAA in the RAA was 12.5% (4/32). Atrial tachyarrhythmia was identified both prenatally (26 and 36 weeks of gestational age) and postnatally (1 and 4 months after birth), with two patients per group, respectively. The RAAAs condition in two patients with atrial tachycardia (AT), concomitant atrial flutter (AF) and atrial fibrillation (Af) was identified using echocardiogram. Although, RAAA in two patients with mono AT was unidentified in echocardiogram and failed to be identified in the procedure of RFCA, RAAA was confirmed during surgical resection of the RAA. Multiple pre-surgical antiarrhythmic medications combined therapy used to treat all four patients showed either no effect at all or was only partially effective. The original atrial tachyarrhythmia was successfully abolished after RAAA surgical resection in four patients. AT originating from new foci was established in two patients post-surgically. The conditions of these two patients were successfully reverted and normal sinus rhythm maintained in the application of antiarrhythmic medications. These results confirmed the efficacy of RAAA surgical resection. The pathology study showed cystic dilation in parts of the atrial cavity, fibrosis of the cyst wall, generalized fibrosis of atrial myocardium with myocardium atrophy and cystic dilation. RAAA is prone to misdiagnosis by echocardiogram. Atrial tachyarrhythmia in patients with RAAA is usually resistant to antiarrhythmic medication therapy and RFCA. Surgical resection of RAAA is a safe and effective option that is minimally invasive.

Hemin blunts the depressant effect of chronic nicotine on reflex tachycardia via activation of central NOS/PI3K pathway in female rats.

BACKGROUND: Chronic nicotine administration impairs reflex chronotropic responses that follow arterial baroreceptor unloading in female rats with repleted, but not depleted (ovariectomized, OVX), estrogen (E2). This study investigated whether products of nitric oxide synthase (NOS) and/or heme oxygenase (HO) and related soluble guanylate cyclase (sGC)/phosphatidylinositol 3-kinase (PI3K)/mitogen-activated protein kinases (MAPKs) signaling mediate the E2-sensitive depressant effect of nicotine on reflex tachycardia. METHODS: Baroreflex curves relating reflex tachycardic responses to falls in blood pressure (BP) generated by sodium nitroprusside (SNP) were established in conscious female rats and slopes of the curves were taken as measures of baroreflex sensitivity (BRS). RESULTS: Nicotine (2 mg/kg/day ip, 14 days) reduced BRS in OVX rats treated with E2 but not vehicle. Baroreceptor dysfunction in nicotine-treated OVXE2 rats was abolished after iv treatment with hemin (HO inducer) but not l-arginine (NOS substrate) denoting the importance of reduced availability of carbon monoxide, but not NO, in the nicotine effect. The favorable BRS effect of hemin was abolished after intracisternal (ic) administration of L-NAME (NOS inhibitor) or wortmannin (PI3 K inhibitor). Central circuits of MAPKs do not seem to contribute to the baroreflex facilitatory effect of hemin because the latter was preserved after central inhibition of MAPKERK (PD98059), MAPKp38 (SB203580) or MAPKJNK (SP600125). Likewise, sGC inhibition (ODQ) or E2 receptor blockade (ICI182780) failed to alter the hemin effect. CONCLUSION: The activation of central NOS/PI3K signaling following HO upregulation improves the E2-dependent depressant effect of nicotine on reflex tachycardia.

Use of low-dose neostigmine intravenously in the treatment of thyroid storm-induced severe tachycardia in patient during huge pelvic mass resection: A case report and review of literature.

RATIONALE: Thyroid storm is a rare and life-threatening metabolic crisis because of an emergent release of excess thyroid hormone. Sinus tachycardia induced by excess thyroid hormone may result in congestive heart failure due to decreased diastolic filling time. PATIENT CONCERNS: A controlled hyperthyroidism patient with severe sinus tachycardia. DIAGNOSES: A controlled hyperthyroidism patient was induced thyroid storm during huge pelvic mass resection. INTERVENTIONS: Application of low-dose neostigmine and ß-antagonist esmolol to control the heart rate (HR) avoided hemodynamic collapse. OUTCOMES: The patient improved dramatically following application of low-dose neostigmine instead of esmolol to control the HR avoided hemodynamic collapse. LESSONS: Our case suggests that neostigmine, an acetylcholinesterase inhibitor, may warrant further investigation in patients with thyroid storm-induced severe sinus tachycardia.

Isolated limb perfusion with cytostatic drug leakage. / Perfusión aislada de extremidad inferior con fuga de quimioterapéutico.

Isolated limb perfusion is the treatment of stage III melanoma with in-transit metastasis. This technique allows the administration of cytostatics at an effective concentration and temperature, which could not be administered systemically because of their toxicity. The toxicity due to leakage of the chemotherapy agent from the limb into the systemic circulation is the most serious short-term complication, and is manifested by a systemic inflammatory response syndrome in the immediate post-intervention period. Early detection of this complication and its peri-operative management requires a multidisciplinary approach, in which the anaesthesiologist plays a key role. A case of isolated lower limb perfusion is reported in which the procedure had to be interrupted due to the passage of tumour necrosis factor into the systemic circulation, with severe intra-operative haemodynamic repercussions.

Reentry Tachycardia in Children: Adenosine Can Make It Worse.

OBJECTIVES: We report on a rare but severe complication of adenosine use in a child with reentry tachycardia. METHODS AND RESULTS: Treatment with adenosine, which is the standard medical therapy of atrioventricular reentry tachycardia, led to the development of an irregular wide complex tachycardia, caused by rapid ventricular response to atrial fibrillation. The girl was finally stabilized with electrical cardioversion. We analyze the pathomechanism and discuss possible treatment options. CONCLUSIONS: Atrial fibrillation, as well as its conduction to the ventricles, can be caused by adenosine. Rapid ventricular response in children with Wolff-Parkinson-White syndrome is more frequent than previously believed. A patient history of atrial fibrillation is a contraindication for cardioversion with adenosine and needs to be assessed in children with reentry tachycardia. High-risk patients may potentially profit from prophylactic comedication with antiarrhythmic agents, such as flecainide, ibutilide, or vernakalant, before adenosine administration.