Progress on treatment of tachyarrhythmia in infants / 中国小儿急救医学

Infant tachycardia is a critical disease, mainly with supraventricular tachycardia and ventricular tachycardia.The treatment of tachycardia in infant is quite different from that of older children, and there is no relevant guidelines at present.Drug therapy in the acute stage of supraventricular tachycardia and atrial fluttery is mainly intravenous adenosine injection.Digoxin is widely used in neonates.Propranolol is the first choice for prophylactic treatment, and landilolol is in the development stage.Ventricular tachycardia can be spontaneously subsided, the treatment is dominated by intravenous lidocaine.For non-drug therapy, heart cardioerter is the emergency treatment for serious rapid arrhythmia.Radiofrequency ablation is used in infants with more severe conditions and where the onset of tachycardia can not be controlled.Bury cardioverter-defibrillator is effective in preventing infant ion channel disease complicated with malignant ventricular tachycardia induced sudden cardiac death.Subcutaneous implantion of a defibrillator may be superior to intravenous implantation in infants and young children.

Progress in the Treatment of Tachyarrhythmia by Pulsed Electric Field Ablation Catheter Ablation / 中国医疗器械杂志

Pulsed electric field(PEF) provides high-energy instantaneous pulse and release energy to myocardial cell membrane, resulting in irreversible electroporation and causes myocardial cell contents leakage, destruction of intracellular homeostasis, cell death, and slight inflammatory response. PEF as non-thermal energy promotes the design and application of arrhythmia ablation catheter to enter a new stage. There are currently limited clinical studies that have proved the safety and effectieness of Farawave PEF catheter, PVAC GOLD PEF catheter, Lattice-tip Sphere-9 PEF and radiofrequency (RF) catheter used for atrial fibrillation ablation, but still need further discussion. The research of atrial fibrillation ablation with PEF is under study in China. In this paper, the design and application of PEF ablation for tachyarrhythmia are reviewed.

Microvolt T-wave alternans complemented with electrophysiologic study for prediction of ventricular tachyarrhythmias in patients with arrhythmogenic right ventricular cardiomyopathy: a long-term follow-up study / 中华医学杂志(英文版)

Background@#The long-term predicted value of microvolt T-wave alternans (MTWA) for ventricular tachyarrhythmia in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) remains unclear. Our study explored the characteristics of MTWA and its prognostic value when combined with an electrophysiologic study (EPS) in patients with ARVC.@*Methods@#All patients underwent non-invasive MTWA examination with modified moving average (MMA) analysis and an EPS. A positive event was defined as the first occurrence of sudden cardiac death, documented sustained ventricular tachycardia (VT), ventricular fibrillation, or the administration of appropriate implantable cardioverter defibrillator therapy including shock or antitachycardia pacing.@*Results@#Thirty-five patients with ARVC (age 38.6 ± 11.0 years; 28 males) with preserved left ventricular (LV) function were recruited. The maximal TWA value (MaxValt) was 17.0 (11.0–27.0) μV. Sustained VT was induced in 22 patients by the EPS. During a median follow-up of 99.9 ± 7.7 months, 15 patients had positive clinical events. When inducible VT was combined with the MaxValt, the area under the curve improved from 0.739 to 0.797. The receiver operating characteristic curve showed that a MaxValt of 23.5 μV was the optimal cutoff value to identify positive events. The multivariate Cox regression model for survival showed that MTWA (MaxValt, hazard ratio [HR], 1.06; 95% confidence interval [CI], 1.01–1.11; P = 0.01) and inducible VT (HR, 5.98; 95% CI, 1.33–26.8; P = 0.01) independently predicted positive events in patients with ARVC.@*Conclusions@#MTWA assessment with MMA analysis complemented by an EPS might provide improved prognostic ability in patients with ARVC with preserved LV function during long-term follow-up.

Assessing Accuracy of Wrist-Worn Wearable Devices in Measurement of Paroxysmal Supraventricular Tachycardia Heart Rate

BACKGROUND AND OBJECTIVES: Wrist-worn wearable devices provide heart rate (HR) monitoring function via photoplethysmography technology. Recently, these devices have been used by patients to measure the HR when palpitation occurs, but few validation studies of these instruments have been conducted. We assessed the accuracy of these devices for measuring a HR. METHODS: This study enrolled 51 consecutive patients with a history of paroxysmal supraventricular tachyarrhythmia (SVT) or paroxysmal palpitations who were scheduled to undergo an electrophysiological study (EPS). Three devices were assessed: Apple Watch Series 2 (Apple), Samsung Galaxy Gear S3 (Galaxy), and Fitbit Charge 2 (Fitbit). Patients were randomly assigned to wear 2 different devices. The HR at baseline and induced SVT were measured during the EPS. After successful ablation of SVT, HR measurements was also done during atrial and ventricular pacing study. RESULTS: The mean patient age was 44.4±16.6 years and 27 patients were male (53%). The accuracy (within ±5 beats per minute [bpm] of an electrocardiogram [ECG] measurement) of the baseline HR measurements was 100%, 100%, and 94%, for Apple, Galaxy, and Fitbit, respectively. The HR during induced SVT ranged from 108 bpm to 228 bpm and the accuracy (within ±10 bpm of an ECG) was 100%, 90%, and 87% for the Apple, Galaxy, and Fitbit, respectively. During pacing study, accuracy of these devices was also acceptable but tended to decrease as the HR increased, and showed differences between the devices. CONCLUSIONS: Wrist-worn wearable devices accurately measure baseline and induced SVT HR. TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0002282

Effect and safety of amiodarone in emergency treatment of tachyarrhythmia / 中国基层医药

Objective To analyze the efficacy and safety of amiodarone in the treatment of patients with tachyarrhythmia in emergency department.Methods The clinical data of 112 patients with emergency tachyarrhythmia admitted to the Emergency Department of the First People's Hospital of Jinzhong from March 2017 to March 2018 were analyzed.According to the different treatment plans applied,the patients were divided into two groups,with 56 patients in each group.The control group was given routine emergency treatment,and the observation group was treated with routine emergency treatment and amiodarone.The efficacy,blood pressure,heart rate and safety in the two groups were compared.Results The total effective rate in the observation group was 91.07％,which was higher than that in the control group(69.64％) (x2 =8.145,P ＜ 0.05).The diastolic blood pressure,systolic blood pressure and heart rate in the observation group were (77.40:±:6.21) mmHg,(124.24 ± 6.15) mmHg and (130.18 ± 6.14) beats/min,respectively,which were lower than those in the control group[(93.47 ± 7.40)mmHg,(140.60 ± 7.48)mmHg and (150.35 ± 12.32) bests/main] (x2 =8.145,t =12.448,12.642,10.966,all P ＜ 0.05).The total incidence rate of adverse reactions in the observation group was 3.57％,which was lower than 19.64％ in the control group (x2 =7.049,P ＜0.05).Conclusion For patients with tachyarrhythimia in the emergency department,the application of amiodarone has significant curative effects and high safety,which can help stabilize their blood pressure,heart rate and improve their conditions,and yet incurs less adverse reactions.Therefore,it is of significant value to be popularized in clinical applications.

Investigation for Current Status of Tachyarrhythmia Treatment in Emergency Patients in Beijing / 中国循环杂志

Objective: To investigate the current status of tachyarrhythmia treatment and outcomes in emergency patients. Methods: A total of 250 tachyarrhythmia patients treated in emergency departments from 1 tertiary hospital, 1 secondary hospital and 1 cardiovascular hospital in Beijing were enrolled. The baseline condition, type of tachyarrhythmia such as atrial fibrillation (AF)/atrial flutter, intravenous medication, prognosis and the choice of anticoagulation therapy were collected and statistically analyzed. Results: The mean age of patients was 64 years including 123/250 (49.2%) female. Common previous histories included 135 (54.0%) cases of hypertension, 93 (37.2%) cases of CAD, 29 (11.6%) cases of stroke/TIA, 29 (11.6%) cases of valvular heart disease and 18 (7.2%) cases of cardiomyopathy; 136 (54.4%) cases combined with organic heart disease. 123 (49.2) cases had previous atrial flutter/AF. The most common type of tachyarrhythmia was AF (172 cases, 68.8%) and the rest in turn, were supra-ventricular tachycardia (41 cases, 16.4%), ventricular tachycardia (23 cases, 9.2%), atrial flutter (21 cases, 8.4%), atrial tachycardia (12 cases, 4.6%) and premature ventricular contraction (5 cases, 2%). The most commonly used drug for treating supra-ventricular tachycardia was propafenone (151 cases, 60.4%), commonly used drug for treating supra-ventricular tachycardia and ventricular arrhythmia was amiodarone. With proper treatment, arrhythmia was stopped in 56% (140 cases), improved in 40% (100 cases) and unchanged or died in 10% (25 cases). 107 non-valvular AF/atrial flutter patients received low molecular heparin for anticoagulation therapy and only 25 patients continued oral anticoagulant therapy after discharge.Conclusion: In our research, most emergency patients were treated consistently with current guidelines. The choice of medication and anticoagulation therapy in AF patients should be improved.

Complejos ventriculares prematuros frecuentes luego de ablación de fibrilación auricular y su relación con el tono autonómico medido por parámetros del Holter / Frequent premature ventricular complexes following ablation of atrial fibrillation and their relationship to the autonomic tone measured with Holter parametres

Resumen Introducción: La ablación con catéter de radiofrecuencia es un tratamiento prometedor para la fibrilación auricular. Pese a su seguridad, se ha evidenciado incremento en la frecuencia de complejos ventriculares prematuros y taquicardia ventricular no sostenida, asociados tal vez con influencias autonómicas. Objetivo: Analizar la actividad autonómica mediante parámetros de monitorización Holter en pacientes llevados a esta intervención. Metodología: Análisis retrospectivo de pacientes con complejos ventriculares prematuros frecuentes luego de aislamiento eléctrico de venas pulmonares por fibrilación auricular, seguidos mediante monitorización Holter entre octubre de 2010 y noviembre de 2014, a fin de comparar parámetros de variabilidad de la frecuencia cardiaca. Resultados: 12,4% tuvo un incremento significativo del automatismo ventricular. Los datos demográficos en los grupos comparados no demostraron diferencias estadísticamente significativas. El promedio de complejos ventriculares prematuros durante las 24 horas fue de 5.363 con 237 por hora. En el grupo de estudio, 65% presentó taquicardia ventricular no sostenida. La variabilidad de la frecuencia cardiaca fue menor en los pacientes del grupo control (p = 0,000). La medida por frecuencias espectrales, evidenció una disminución en la frecuencia LF y HF para ambos grupos, con un valor menor para el grupo control (p = 0,000). La relación LF/HF para ambos grupos fue elevada (p = 0,612). Conclusión: La ablación de venas pulmonares en el tratamiento de la fibrilación auricular puede conducir al desarrollo de complejos ventriculares prematuros frecuentes y taquicardia ventricular. El impacto sobre el sistema parasimpático y simpático puede ser un factor que precipite esta condición.

Abstract Introduction: Radiofrequency catheter ablation is a promising treatment for atrial fibrillation. Despite its security, and increase in the frequency of premature ventricular complexes and nonsustained ventricular tachycardia has been evidenced, which could have autonomic influences. Motivation: To analyse autonomic activity using Holter monitoring parametres in patients who underwent this procedure. Methods: Retrospective analysis of patients with frequent premature ventricular complexes following electric isolation of pulmonary veins due to atrial fibrillation, followed up with Holter monitorisation between October 2010 and November 2014 with the goal of comparing heart rate variability parametres. Results: 12.4% had a significant increase of ventricular automacity. Demographic data in compared groups did not reveal statistically significant differences. The average of premature ventricular complexes within 24 hours was of 5,363, with 237 per hour. In the study group, 65% showed non-sustained ventricular tachycardia. Heart rate variability was lower in patients from the control group (p = 0.000). Evaluation of spectral frequency evidenced a decrease in LF and HF for both groups, with a lower value for the control group (p = 0.000). HF/LF relationship for both groups was high (p = 0.612). Conclusion: Ablation of pulmonary veins in the treatment of atrial fibrillation can lead to the development of frequent premature ventricular complexes and ventricular tachycardia. The impact on the parasympathetic and sympathetic system could be a factor that triggers this condition.

Síndrome de Brugada como causa de muerte súbita de origen cardíaco / Brugada syndrome as a cause of sudden cardiac death

ResumenMuerte súbita se define como un evento fatal e inesperado que ocurre en un individuo aparentemente sano. Una de las principales causas son las de origen cardiovascular, entre las cuales se encuentran las anormalidades electrofisiológicas primarias como lo es el síndrome de Brugada. Este se define como una canalopatía que afecta canales de sodio, producto de una variante genética, principalmente de herencia autosómica dominante.Se ha determinado que la mutación del gen SCN5A es la más asociada con el síndrome. El diagnóstico se realiza mediante historia clínica y patrones electrocardiográficos específicos y generalmente se presenta como síncope o como muerte súbita resucitada debida a taquicardia ventricular polimórfica o fibrilación ventricular. El desfibrilador automático implantable es la principal herramienta para la prevención de muerte súbita, sin embargo, previo a su uso debe hacerse una adecuada estratificación de los pacientes, tanto para prevenir muerte súbita, como para evitar el uso innecesario del dispositivo.

AbstractSudden death is defined as an unexpected fatal event occurring in an apparently healthy subject. Sudden cardiac death is a leading cause, among which are primary electrical abnormalities such as Brugada Syndrome. Brugada Syndrome is an autosomal dominant channelopathy affecting the sodium channel. SCN5A has emerged as the most common gene associated with Brugada syndrome. The diagnosis is suggested by the clinical history in a patient with specific electrocardiographic pattern. The most typical presentation is syncope or resuscitated sudden death due to polymorphic ventricular tachycardia or ventricular fibrillation. An implantable cardioverter defibrillator is the main tool for preventing sudden death, and correct risk stratification in these patients is important both to prevent sudden death and to avoid unnecessary implantable cardioverter defibrillator use.

Analysis of Therapeutic Efficacy of Shensong Yangxin Capsule Combined with Low-dose Amiodarone in the Treatment of Ventricular Tachyarrhythmia / 中国药房

OBJECTIVE:To observe therapeutic efficacy and safety of Shensong yangxin capsule combined with low-dose ami-odarone in the treatment of ventricular tachyarrhythmia. METHODS:In retrospective analysis,106 patients with ventricular tachyar-rhythmia were divided into control group and observation with 53 cases in each group according to drug use. Based on conventional treatment,control group was additionally given Amiodarone tablet (first week:0.2 g each time,3 times a day;second week:0.2 g each time,2 times a day;third week to the end of the treatment:0.2 g each time,1 times a day),orally. Observation group was given Amiodarone tablet (first week:0.2 g each time,twice a day;second week to the end of the treatment:0.2 g each time,1 times daily),orally +Shensong yangxin capsule 1.6 g,3 times a day,orally. Both groups were treated for 8 weeks. Clinical effica-cy,blood pressure,heart rate and electrocardiogram(PR period and QT period)and the cardiac cardioversion time were compared between 2 groups,and the occurrence of ADR was also recorded during treatment. RESULTS:After treatment,total response rate of observation group(94.34%)was higher than that of control group(81.13%),the incidence of ADR was lower than that of con-trol group (3.77% vs. 13.21%) and the cardiac cardioversion time was shorter than that of control group,with statistical signifi-cance(P0.05). CONCLUSIONS:Based on conventional treatment, Shensong yangxin capsule combined with low-dose amiodarone have good therapeutic efficacy with rapid response for ventricular arrhythmia,it can significantly improve the heart rate of the patients,and the effect is faster with good safety .

Tachycardia-induced cardiomyopathy in children / 中华实用儿科临床杂志

Tachycardia-induced cardiomyopathy (TIC) is defined as a kind of cardiomyopathy with cardiac dilatation and dysfunction secondary to sustained or recurrent tachyarrhythmia.Myocardial dysfunction can wholly or partially recover after control of the responsible tachyarrhythmia.TIC,a reversible acquired cardiomyopathy with generally benign prognosis,can occur at any age;however,it often proves to be unrecognized by most of pediatricians in clinical practices.Now,the clinical criteria,pathogenesis,characteristics,therapy and prognosis of pediatric TIC were summarized,so as to provide a clinical basis for early recognition and prompt therapy.

Meta-analysis on risk stratification of malignant ventricular tachyarrhythmic events in arrhythmogenic right ventricular cardiomyopathy / 영남의대학술지

BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a cardiomyopathy characterized by predominant right ventricular fibro-fatty replacement, right ventricular dysfunction and ventricular arrhythmias. It is a rare but important cause of sudden cardiac death in children and young adults. A meta-analysis on risk stratification of major ventricular tachyarrhythmic events indicating the need for implantable cardioverter defibrillator therapy in ARVC was performed.METHODS: The pubmed database was searched from its inception to May 2015. Of the 433 citations identified, 12 were included in this meta-analysis. Data regarding major ventricular tachyarrhythmic events were retrieved in 817 subjects from the studies. For the variables, a combined odds ratio (OR) was calculated using a fixed-effects meta-analysis.RESULTS: Extensive right ventricular dysfunction (OR, 2.44), ventricular late potential (OR, 1.66), inducible ventricular tachyarrhythmia during electrophysiology study (OR, 3.67), non-sustained ventricular tachycardia (OR, 3.78), and history of fatal event/sustained VT (OR, 5.66) identified as significant risk factors (p < 0.0001).CONCLUSION: This meta-analysis shows that extensive right ventricular dysfunction, ventricular late potential, inducible ventricular tachyarrhythmia during electrophysiological study, non-sustained ventricular tachycardia, and history of sustained ventricular tachycardia/fibrillation are consistently reported risk factors of major ventricular tachyarrhythmic events indicating implantable cardioverter defibrillator therapy in patients with ARVC.

Meta-analysis on risk stratification of malignant ventricular tachyarrhythmic events in arrhythmogenic right ventricular cardiomyopathy / 영남의대학술지

BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a cardiomyopathy characterized by predominant right ventricular fibro-fatty replacement, right ventricular dysfunction and ventricular arrhythmias. It is a rare but important cause of sudden cardiac death in children and young adults. A meta-analysis on risk stratification of major ventricular tachyarrhythmic events indicating the need for implantable cardioverter defibrillator therapy in ARVC was performed. METHODS: The pubmed database was searched from its inception to May 2015. Of the 433 citations identified, 12 were included in this meta-analysis. Data regarding major ventricular tachyarrhythmic events were retrieved in 817 subjects from the studies. For the variables, a combined odds ratio (OR) was calculated using a fixed-effects meta-analysis. RESULTS: Extensive right ventricular dysfunction (OR, 2.44), ventricular late potential (OR, 1.66), inducible ventricular tachyarrhythmia during electrophysiology study (OR, 3.67), non-sustained ventricular tachycardia (OR, 3.78), and history of fatal event/sustained VT (OR, 5.66) identified as significant risk factors (p < 0.0001). CONCLUSION: This meta-analysis shows that extensive right ventricular dysfunction, ventricular late potential, inducible ventricular tachyarrhythmia during electrophysiological study, non-sustained ventricular tachycardia, and history of sustained ventricular tachycardia/fibrillation are consistently reported risk factors of major ventricular tachyarrhythmic events indicating implantable cardioverter defibrillator therapy in patients with ARVC.

Caracterización de pacientes con síndrome de apnea e hipopnea obstructiva del sueño llevados a Holter electrocardiográfico de 24 horas / Characterisation of patients with obstructive sleep apnoea/hypopnoea syndrome with 24-hour ECG Holter monitoring

Introducción: El síndrome de apnea/hipopnea del sueño se ha asociado a alteraciones en el ritmo cardíaco, sin embargo, en nuestro medio hay pocos datos acerca de las características clínicas y los trastornos del ritmo en sujetos con el síndrome llevados a Holter electrocardiográfico. Métodos: Se desarrolló un estudio descriptivo de serie de casos, con toma de datos de historia clínica, en cuanto a edad, género, antecedentes médicos, ecocardiograma, resultados de polisomnografía y diagnóstico de Holter electrocardiográfico en pacientes con síndrome de apnea/hipopnea obstructiva del sueño en un centro de tercer nivel de atención. Resultados: Se analizaron 149 registros, con edad promedio de 63,01 años (DE: 11,76); 101 pacientes (67,8%) presentaron algún tipo de trastorno del ritmo cardíaco y 86 (57,7%) algún tipo de arritmia. El sexo femenino y la enfermedad pulmonar obstructiva crónica se relacionaron con la presencia de arritmia cardíaca (p < 0,05). Conclusión: En este estudio la presencia de arritmias cardiacas en pacientes con síndrome de apnea/hipopnea obstructiva del sueño llevados a Holter electrocardiográfico, fue de 57,7%; en este sentido, el trastorno más frecuente fueron las extrasístoles ventriculares y contribuyeron con un 28,9%. El sexo femenino y la enfermedad pulmonar obstructiva crónica pueden guardar relación con el incremento de trastornos del ritmo cardíaco en los pacientes con síndrome de apnea/hipopnea obstructiva del sueño. Se requieren estudios analíticos para corroborar estos hallazgos.

Introduction: Sleep apnoea-hypopnoea syndrome has been associated to heart rate alterations; however, in our fields there is few data of the clinical characteristics and heart rate disorders in individuals with this syndrome who have been subject to 24-hours ECG Holter monitoring. Methods: This is a case series descriptive study, with data collection of clinical records including age, gender, medical history, echocardiogram, polysomnography results and ECG Holter monitoring diagnosis in patients with obstructive sleep apnoea hypopnoea syndrome at a third level centre. Results: 149 registers were analysed, with an average age of 63.01 (SD: 11.76); 101 patients (67.8%) showed some kind of heart rate disorder and 86 (57.7%) some type of arrhythmia. Being female and suffering from obstructive pulmonary disease were related to the presence of heart arrhythmia (p < 0.05). Conclusion: In this study the presence of heart arrhythmias in patients with obstructive sleep apnoea hypopnoea syndrome subject to 24-hour ECG Holter monitoring was of 57.7%; the most common disorder were ventricular extrasystoles, which accounted for 28.9%. Being female and suffering from obstructive pulmonary disease could be linked with an increase of heart rate disorders in patients with obstructive sleep apnoea hypopnoea syndrome. Analytical studies are required to corroborate the findings.

Diferencias entre 2 electrocardiogramas sinusales como predictoras de fibrilación auricular: estudio de cohorte / Variations between 2 ECG as predictors of atrial fibrillation: Cohort study

Resumen Objetivo Evaluar la asociación entre las diferencias de mediciones de 2 ECG separados en el tiempo, con el desarrollo de fibrilación auricular (FA). Método Cohorte retrospectiva de 9,975 pacientes adultos, afiliados a la prepaga del Hospital Italiano de Buenos Aires, Argentina, con realización de al menos 2 ECG sinusales digitales entre 2006-2011. Se siguieron clínicamente para la detección de FA. Todas las mediciones electrocardiográficas y los deltas (diferencias entre los 2 ECG) fueron estandarizadas. Se estimaron los hazard ratio para desarrollo de FA, para cada delta de los distintos componentes electrocardiográficos utilizando un modelo de regresión de Cox. Resultados Durante una mediana de seguimiento de 3,5 años se detectaron 189 episodios de FA. El delta FC, delta intervalo ST y delta amplitud onda P se asociaron significativamente a FA. Ajustado por características clínicas y mediciones de ECG basal, el hazard ratio ajustado para FA fue 0.86 (IC95%: 0.75-0.98, p = 0.024) para delta FC; 1.12 (IC95%0.98-1.27, p = 0.082) para delta intervalo ST; y 1.21 (IC95%: 1.05-1.38, p = 0.006) para delta amplitud onda P. Conclusiones Las diferencias FC y amplitud onda P, entre mediciones de ECG, predicen FA en forma independiente de características clínicas y mediciones de ECG basal.

Abstract Objetive To evaluate the association between delta variations in the parameters of 2 sinusal ECG with atrial fibrillation (AF) onset. Method Retrospective cohort of 9,975 adult patients and members of the prepaid system at Hospital Italiano de Buenos Aires from Argentina, who had at least 2 sinusal ECG between 2006 and 2011. Population was followed up for detection of AF. All measurements and electrocardiographic deltas (differences between the 2 ECG) were standardized. Hazard ratio (HR) was estimated for the development of AF for each delta of the different ECG parameters using a Cox regression model. Results During a median follow up of 3.5 years, 189 patients (1.89%) developed AF. Heart rate delta, ST interval delta and P wave amplitude were predictors of AF. Hazard ratio Adjusted for clinical characteristics and ECGbasal values was 0,86 (CI95%: 0.75-0.98, p = 0.024) for heart rate delta, 1.12 (CI95%: 0.98-1.27, p = 0.082) for ST interval delta and 1.21 (CI95%: 1.05-1.38, p = 0.006) for P wave amplitude delta. Conclusion Differences of heart rate and P wave amplitude between ECG's measurements may predict AF, independently of clinical features and ECGbasal values.

The alteration of energy metabolism and oxidative injury in the myocardia suffering from lethal ventricular ;tachyarrhythmia ( / 中国法医学杂志

Objective To investigate the alteration of energy metabolism and oxidative injury in the myocardia suffering from lethal ventricular tachyarrhythmia (LVTA). Methods Two LVTA-SCD SD rat models, induced by aconitine injection or coronary artery ligation (CAL), respectively, were developed. Rats that died from over-anaesthesia or CAL-induced heart failure were served as their controls, respectively. Mitochondrial membrane potential (MMP), reactive oxygen species (ROS), malonaldehyde (MDA), phosphocreatine (PCr) in the ventricular myocardia, and serum troponin I (cTnI) were detected, and compared between LVTA rats and their controls. Results Fourteen ACO-LVTA and six CAL-LVTA rats were successfully developed. As compared to their controls, ACO-LVTA and CAL-LVTA rats had higher ROS and MDA content, and lower concentration of PCr in the ventricular myocardia. MDA content in ACO-LVTA group is signiifcantly higher than that of its control (P<0.05). MMP in myocardia of ACO-LVTA is lower than that of its control, but is higher than those of two CAL groups. Serum cTnI in rats of both LVTA models is higher than those of their controls and pre-treated control. Specially, serum cTnI in CAL-LVTA was signiifcantly higher than that of ACO-LVTA and its control (P<0.01). The myocardial ROS content is correlated with the duration of VT and VF (P<0.05), with correlation coefifcients being 0.44 and 0.46, respectively. Conclusions After LVTA, the ventricular myocardia had lower MMP and PCr content, higher concentration of ROS, MDA, as well as higher serum cTnI than their controls, indicative of oxidative injury and alteration of energy metabolism under LVTA-SCD.

Radiofreqeuncy Catheter Ablation for Tachyarrhythmia / 대한내과학회지

Radiofrequency (RF) refers to the portion of the electromagnetic spectrum in which electromagnetic waves can be generated by feeding an alternating current to an antenna. RF energy is electrically conducted, not radiated, during catheter ablation, and RF rarely induces rapid polymorphic arrhythmias. When using RF to measure lesion size in a steady state, the lesion size is proportional to the temperature measured at the tissue-electrode interface and the RF power amplitude. Focal ablation using RF is the treatment of choice for all supraventricular tachyarrhythmias, including AV nodal reentry, tachycardias with concealed accessory pathways, incessant automatic atrial tachycardia, isthmus dependent atrial flutter, and other macroreentrant atrial tachycardias. The isolation of pulmonary veins by RF energy has been successful for paroxysmal atrial fibrillation.

Organophosphorous intoxication and hyperthyroidism.

It is well established that transient thyroid dysfunction can occur in many non-thyroid illness. But abnormal thyroid function test in the range of hyperthyroidism is not reported many a times. Here we present two cases of chlorpyrifos intoxication presenting with hyperthyroidism and its implications in the management of the patient in acute illness. Role of atropine in antagonizing muscarinic effects of organophosphorus intoxication is well documented. Interplay between atropine, hyperthyroid state and tachycardia discussed.

Manejo terapeútico de algunas arritmias fetales / Therapeutic management of some fetal arrhythmias

Introducción: la electrocardiografía fetal constituye la prueba de oro para el diagnóstico de las arritmias en la vida posnatal, algo difícil de lograr en la vida prenatal incluso con la ecografía prenatal de alta resolución. Las taquiarritmias supraventriculares son las que se manifiestan con frecuencias cardíacas superiores a 180 latidos por min y pueden asociarse a mortalidad fetal en un tercio de los casos, sobre todo cuando se asocia a hidropesía fetal o cuando se establece por más de 15 días. El tratamiento permite la reversión de la arritmia o el control ventricular en el menor tiempo posible. Objetivos: comprobar la respuesta intraútero de la taquiarritmia al tratamiento farmacológico. Métodos: se realizó un estudio descriptivo prospectivo observacional de un universo de 24 fetos con el diagnóstico de taquiarritmia fetal que se diagnosticaron y atendieron en el Departamento Provincial de Genética de La Habana y en el Hospital Ginecobstétrico "Ramón González Coro" entre los años 2003 y 2012. Resultados: las taquiarritmias se observaron en 24 fetos (40,6 %). Las madres menores 30 años fueron las más representadas en el grupo de mujeres del estudio, unido al índice de masa corporal sobrepeso y específicamente las pacientes nulíparas. Casi la mitad de la muestra no requirió tratamiento farmacológico (45,8 %) todas con el diagnóstico ecocardiográfico de extrasístoles y sola una con compromiso orgánico del corazón. Conclusiones: la flecainida se utilizó, en la cuarta parte de la muestra y mostró una resolutividad de 83,3 % en los fetos intraútero. La sobrevida de los fetos tratados farmacológicamente por vía oral fue 100 %.

Introduction: fetal electrocardiography is the gold standard for diagnosis of arrhythmias in postnatal life. This is difficult to achieve in prenatal life even with high-resolution prenatal ultrasound. Supraventricular tachyarrhythmias are manifested with heart rates above 180 beats per min and may be associated with fetal death in one third of cases, especially when associated with fetal hydrops or when it is set for over 15 days. Treatment allows the reversal of ventricular arrhythmia or control in the shortest possible time. Objective: to test tachyarrhythmia in uterus response to drug treatment. Methods: an observational prospective descriptive study was conducted in a universe of 24 fetuses with the diagnosis of fetal tachyarrhythmia that were diagnosed and treated at the Provincial Department of Genetics, Havana and at the Ramón González Coro Maternal Hospital from 2003 to 2012. Results: tachyarrhythmias were observed in 24 fetuses (40.6 %). Mothers younger than 30 were the most represented in this study group, together with BMI overweight and nulliparous patients specifically. Almost half of the sample did not require drug (45.8 %) treatment, all with extrasystoles echocardiographic diagnosis and only one with organic heart involvement. Conclusions: flecainide was used in a quarter of the sample and showed 83.3 % resoluteness of fetuses in uterus. Survival of fetuses pharmacologically orally treated was 100 %.

Cellular electrophysiologic mechanisms of tachyarrhythmia in rabbits induced by positive acceleration / 军事医学

Objective To investigate the effect of positive acceleration (+Gz) on monophasic action potential duration of 90%repolarization( MAPD90 ) and transmural dispersion of repolarization ( TDR) in ventricles of rabbits and to explore the cellular electrophysiologic mechanism of tachyarrhythmia induced by positive acceleration .Methods Twenty-four healthy, male New Zealand white rabbits were randomly and equally divided into control group and +Gz group.The +Gz group rabbits were given +8 Gz exposure, 1 min a time, 3 times a day,and a total of 7 days.The two groups were subjec-ted to Holter monitoring at the same time to observe the incidence of tachyarrhythmia .Using the monophasic action potential ( MAP) recording technology , the MAP of the left ventricle was recorded while MAPD 90 and TDR were measured .By using Burst stimulation method , the right ventricular anterior wall of the rabbits was stimulated , and the incidence of tachya-rrhythmia was observed .Results The Holter record showed that the incidence of tachyarrhythmias in +Gz group was 55%(6/11), but the control group did not have any case of tachyarrhythmias .Compared with the control group ,MAPD90 of en-docardial and epicardial cells was significantly decreased in the +Gz group, while MAPD90 of middle myocardial cells did not change significantly ,but TDR was increased obviously .Four rabbits in +Gz group suffered from tachyarrhythmias dur-ing Burst stimulation ,and the incidence of tachyarrhythmias was 40% ( 4/10 ) .Conclusion +Gz exposure can increase the incidence of tachyarrhythmias .The shortened MAPD90 of ventricular muscle cells and the increased TDR may be the cell electrophysiological mechanisms of tachyarrhythmias induced by +Gz.

Reversible cerebral vasoconstriction syndrome secondary to catheter ablation / Síndrome de vasoconstrição reversível secundária à ablação por cateter

We report a case of a 41-year-old woman with chagasic cardiomyopa-thy who was submitted to ventricular septal catheter ablation. After the procedure she evolved with new-onset thunderclap headaches followed by migraine-type headaches. Cerebral angiography revealed bilateral segmental stenosis of the middle cerebral arteries.

Relatamos um caso de uma mulher de 41 anos de idade, portadora de cardiomiopatia chagásica, que foi submetida à ablação ventricu-lar septal por cateter. Após o procedimento, a paciente apresentou cefaleia em trovoada de início recente seguida de cefaleia do tipo migranosa. A angiografia cerebral revelou estenoses segmentares bilaterais em território de artéria cerebral média.