Research Progress on the Molecular Mechanisms of Toxicology of Ethanol-Aconitine Induced Arrhythmia / 法医学杂志

Aconitum is one of the most widely used Chinese herbal medicines, and aconitine is the major toxic component in it. Aconitine can induce a variety of arrhythmias, resulting in death. Acute ethanol consumption causes arrhythmia as well. Poisoning cases caused by aconitum medicinal liquor are frequently encountered in the practice of forensic medicine. The molecular mechanisms of myocardial toxicity of these two drugs have much in common, and both of them affect the sodium channel, calcium channel and potassium channel of myocardial cell membrane and so on. This paper analyzes and discusses the possible co-effects of ethanol-aconitine on cardiomyocyte channel proteins, by reviewing researches on the mechanism of cardiotoxicity of ethanol and aconitine in recent years, in order to provide ideas and references for the research on the molecular mechanism of arrhythmia caused by combined poisoning.

Oclusión total de la arteria coronaria derecha y disfunción de la arteria del nodo sinoatrial / A total occlusion of the right coronary artery and a dysfunction of the sinoatrial node artery

Resumen La arteria del nodo sinoatrial irriga al marcapasos principal del corazón y su oclusión o lesión puede generar arritmias. Se reportó un infarto de miocardio inferior, el cual presentó oclusión total trombótica proximal de la coronaria derecha, y presentó desde extrasístoles atriales hasta bloqueo atrioventricular. Se describieron las 6 rutas que puede seguir la arteria del nodo sinoatrial y las distintas manifestaciones clínicas que puede tener su oclusión o daño. Se deben realizar estudios de prevalencia para conocer la distribución de esta arteria en la población mexicana, y poder predecir con mayor probabilidad los trastornos del ritmo.

Abstract The sinus node artery irrigates the main pacemaker of the heart and its occlusion or damage can generate arrhythmias. We reported the case of a patient that had an inferior myocardial infarction due to total thrombotic occlusion of the proximal right coronary artery, atrial premature beats and an atrioventricular block. We described the 6 routes that the sinus node artery can follow and the different clinical manifestations that can be observed if occluded. Prevalence studies should be conducted to determine the distribution of this artery in the Mexican population, and to be able to predict rhythm disorders with a higher probability.

Arrhythmogenic potential develops rapidly at graft reperfusion before the start of hypotension during living-donor liver transplantation / 대한마취과학회지

BACKGROUND: Detailed profiles of acute hypothermia and electrocardiographic (ECG) manifestations of arrhythmogenicity were examined to analyze acute hypothermia and ventricular arrhythmogenic potential immediately after portal vein unclamping (PVU) in living-donor liver transplantation (LT). METHODS: We retrospectively analyzed electronically archived medical records (n = 148) of beat-to-beat ECG, arterial pressure waveforms, and blood temperature (BT) from Swan-Ganz catheters in patients undergoing living-donor LT. The ECG data analyzed were selected from the start of BT drop to the initiation of systolic hypotension after PVU. RESULTS: On reperfusion, acute hypothermia of < 34degrees C, < 33degrees C and < 32degrees C developed in 75.0%, 37.2% and 11.5% of patients, respectively. BT decreased from 35.0degrees C +/- 0.8degrees C to 33.3degrees C +/- 1.0degrees C (range 35.8degrees C-30.5degrees C). The median time to nadir of BT was 10 s after PVU. Difference in BT (DeltaBT) was weakly correlated with graft-recipient weight ratio (GRWR; r = 0.22, P = 0.008). Compared to baseline, arrhythmogenicity indices such as corrected QT (QTc), Tp-e (T wave peak to end) interval, and Tp-e/QTc ratio were prolonged (P < 0.001 each). ST height decreased and T amplitude increased (P < 0.001 each). However, no correlation was found between DeltaBT and arrhythmogenic indices. CONCLUSIONS: In living-donor LT, regardless of extent of BT drop, ventricular arrhythmogenic potential developed immediately after PVU prior to occurrence of systolic hypotension.

Ventricular Tachycardia due to Perinatal Asphyxia.

Background: Perinatal asphyxia is known to precipitate myocardial dysfunction, rhythm abnormalities and congestive cardiac failure. Case characteristics: A 2-day old neonate with perinatal asphyxia. Observation: He developed shock secondary to ventricular tachycardia, and required synchronized cardioversion for reversion of abnormal rhythm. Outcome: Reversal of arrhythmia leading to recovery. Message: Early identification and management of ventricular tachycardia in neonate with perinatal asphyxia can be lifesaving.

Ritmo nodal secundario a descarga eléctrica de alto voltaje: Report of one case / Transient high frequency nodal rhythm after a high voltage electric shock

Electrical shock can cause a direct myocardial damage and different types of arrhythmias, which are uncommon and occur more often when there is a high voltage exposure. We report a 19-year-old male that received a high voltage shock, falling thereafter from an altitude of four meters. On admission to the emergency room, he had second and third degree burns in the right hand and the left thigh. The electrocardiogram showed a nodal rhythm of 72 beats per minute. After four hours of monitoring, sinus rhythm returned spontaneously.

The value of T wave alternans in prediction of ventricular arrhythmias in post-op TOF children / 临床儿科杂志

Objective To explore the value of T wave alternans (TWA) in prediction ventricular arrhythmias in post-op TOF children. Methods The characteristics of TWA were retrospectively analyzed in 36 post-op TOF patients and 120 age-matched normal children. The relationship of sustained TWA and ventricular arrhythmias was also analysed. Results Compared with normal children, the incidence of sustained TWA was significantly increased in post-op TOF group (χ2=6.98, P<0.05). In post-op TOF patients, the incidence of ventricular arrhythmia was much higher when sustained TWA was present (χ2=10.41, P<0.05). Conclusions There exists electrophysiological basis for ventricular arrhythmia in post-op TOF children. Sustained TWA has important value in prediction of ventricular arrhythmia of post-op TOF.

Correlation between single nucleotide polymorphism H558R in SCN5A gene and chronic Keshan Disease complicated with hypertension, and their electrocardiogram characteristics / 中国地方病学杂志

Objectives To investigate the relationship between single nucleotide polymorphism (SNP)H558R in SCN5A gene and chronic Keshan disease (KSD) complicated with hypertension,and the relationship between H558R and occurrence of arrythmia in chronic KSD complicated with hypertension.MethodsThirty nine patients with chronic KSD complicated with hypertension and 63 geographical region matched hypertension control subjects were recruited in our study in Fuyu county,Qiqihaer city,Heilongjiang province between 2006 and 2010.H558R polymorphism in case and control groups was genotyped using the polymerase chain reaction single-strand conformation polymorphism(PCR-SSCP) and sequenced,and electrocardiography(ECG) characteristics were examined in the two groups.Case-control study analytical methods were applied to analyze the relationship between H558R and chronic KSD complicated with hypertension,and the relationship between H558R and occurrence of arrythmia in chronic KSD patients complicated with hypertension.Results Subjects of genotype 558 TC in the case group had a decreased risk of chronic KSD complicated with hypertension with odds ratio of 0.288[95％ confidence interval (CI):0.104 - 0.794],and subjects of genotype TC in chronic KSD complicated hypertension patients had a decreased risk of QRS prolongation with odds ratio of 0.061 (95％CI:0.006 - 0.612).Conclusions Polymorphism H558R in SCN5A gene may be a predisposition factor of chronic KSD complicated with hypertension and occurrence of arrythmia in chronic KSD complicated with hypertension.

A Case of Sick Sinus Syndrome in Extremely Low Birth Weight Infant with Annular Pancreas

Sick sinus syndrome (SSS) is a disorder characterized by sinus node dysfunction. Although the condition is most common in the elderly, it can occur in children including neonates and its recognition and treatment are important. The diagnosis of SSS is based on the presence of sinus bradycardia, sinus arrest or exit block, combinations of sinoatrial and atrioventricular nodal conduction disturbances, and atrial tachyarrhythmias documented in the Holter recordings. In most children with SSS, previous history of congenital heart malformation or cardiac surgery is noted. SSS is also seen in the children including neonates without heart disease or other contributing factors, however SSS is most often idiopathic. The treatment of SSS depends on the basic rhythm problem, but generally involves the placement of a cardiac pacemaker. We report a case of SSS in extremely low birth weight infant without congenital heart disease and suggest that the treatment system is necessary for preterm infants with SSS.

Early Onset Hyperkalemia in Very Low Birth Weight Infants

PURPOSE:This study was designed to know the clinical significance and risk factors of hyperkalemia in very low birth weight infants (VLBWI). METHODS:We compared the incidence of hyperkalemia and its associated ECG abnormalities and mortality rate according to birth weight (102 of less than 1,000 g vs. 328 of 1,000 to 1,500 g) in 430 VLBWI who were born from Jan. 2000 to July 2004, retrospectively, and also compared the several parameter according to serum potassium (35 of hyperkalemia vs. 11 of normokalemia) in 49 selected VLBWI who need mechanical ventilation for respiratory distress without oliguria within 72 hours of life to know the risk factors of hyperkalemia. RESULTS:Overall incidence of hyperkalemia in VLBWI was 21.1%, and was significantly higher in below 1,000 g than in 1,000 to 1,500 g (32.4% vs. 17.7%, P<0.05). Hyperkalemia associated ECG abnormalities, life-threatening cardiac arrhythmia, and death were also significantly higher in below 1,000 g. There were no significant differences in maternal or infant's characteristics, laboratory findings and clinical conditions between hyperkalemic vs. normokalemic group. The incidence of cardiac arrhythmia and mortality rate were also significantly higher in hyperkalemic group. CONCLUSION:Early onset nonoliguric hyperkalemia is often associated with life- threatening cardiac arrhythmia and death in VLBWI, especially less than 1,000 g. Although perinatal risk factors were not found in this study, prospective study is needed to establish the preventive strategy and to improve the outcome.

Effects of lappaconitine on the toxicity and analgesic activity of 3-acetylaconitine in their combination / 中国药理学通报

Lappaconitine (LA) 0. 5 mg? kg-1had significant antagonistic action on the ar-rythmia induced by 3-acetylaconitine ( AA ) 0.07 mg?kg-1in rat. When LA and AA were used in combination (7:1) in mice, the analgesic activity of AA was not influenced marked-ly by LA but the LD50 of AA was increased by 50% ,therefore the therapeutic index of AA was increased and the margin of safety was widened.