ABSTRACT
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.
ABSTRACT
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.
Subject(s)
Humans , Death, Sudden, Cardiac , Death, Sudden , Brugada Syndrome , Brugada Syndrome/epidemiology , Channelopathies , Forensic MedicineABSTRACT
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 .
ABSTRACT
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.
Subject(s)
Child , Humans , Young Adult , Arrhythmias, Cardiac , Arrhythmogenic Right Ventricular Dysplasia , Cardiomyopathies , Death, Sudden , Death, Sudden, Cardiac , Defibrillators , Electrophysiology , Odds Ratio , Risk Factors , Tachycardia , Tachycardia, Ventricular , Ventricular Dysfunction, RightABSTRACT
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.
Subject(s)
Child , Humans , Young Adult , Arrhythmias, Cardiac , Arrhythmogenic Right Ventricular Dysplasia , Cardiomyopathies , Death, Sudden , Death, Sudden, Cardiac , Defibrillators , Electrophysiology , Odds Ratio , Risk Factors , Tachycardia , Tachycardia, Ventricular , Ventricular Dysfunction, RightABSTRACT
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.
ABSTRACT
BACKGROUND: Aspirin, one of the antiplatelet agents, improves the survival rate after myocardial infarction. This beneficial effect is known to be obtained in part by the antiarrhythmic action of aspirin. It is not known whether other antiplatelet agents have such effects. This study was performed to compare the effects of aspirin, ticlopidine, and abciximab (platelet glycoprotein IIb/IIIa receptor antagonist) on the ischemia-induced arrhythmias with a rat model of cardiac regional ischemia. METHODS: Experiments were performed in 4 groups of rats. The 4 groups were as follows : control, n=10:aspirin-pretreated, 300 mg/kg po for 1 week:ticlopidine-pretreated, 200 mg/kg po for 1 wk:abciximab-pretreated, 2 mg/kg iv 10-20 minutes before experiment. The electrocardiogram and blood pressure were recorded during 20 minutes. The time to the onset of ST-segment elevation and ventricular tachyarrhythmias, frequency and incidence of ventricular tachyarrhythmias, and death rate were assessed during acute myocardial ischemia induced by ligation of proximal left anterior descending coronary artery in anesthetized rats. RESULTS: Platelet aggregations to ADP were significantly lower in aspirin (42.8%), ticlopidine (43.8%), and abciximab group (34.0%) than in control group (66.4%). The frequencies of sustained ventricular tachycardia (VT) were 6.8+/-3.6 in control, 3.6+/-3.8 aspirin, 4.7+/-3.7 ticlopidine, and 1.4+/-2.5 abciximab group. The frequency of sustained VT in the abciximab group was significantly lower than in control group. The incidences of ventricular arrhythmias for 20 min were 10/10 for VT and 8/10 for ventricular fibrillation (VF) in control group, 7/10 for VT and 3/10 for VF in aspirin group, 10/10 for VT and 3/10 for VF in ticlopidine group, and 5/10 for VT and 4/10 for VF in abciximab group. The incidences of cardiac death during 20 min were 8/10 in control group, 4/10 in aspirin group, 2/10 in ticlopidine group and 5/10 in abciximab group. The incidence of VT in the abciximab group was significantly lower than in control group, incidences of VF in the aspirin and ticlopidine groups were significantly lower than in control group, and death rate in ticlopidine group was significantly lower than in control group. CONCLUSION: The present study suggested that aspirin, ticlopidine, and abciximab could prevent ventricular tachycardia or ventricular fibrillation in a rat model of cardiac regional ischemia and their antiarrhythmic effects improve the survival rate.
Subject(s)
Animals , Rats , Adenosine Diphosphate , Arrhythmias, Cardiac , Aspirin , Blood Platelets , Blood Pressure , Coronary Vessels , Death , Electrocardiography , Glycoproteins , Incidence , Ischemia , Ligation , Models, Animal , Mortality , Myocardial Infarction , Myocardial Ischemia , Platelet Aggregation Inhibitors , Survival Rate , Tachycardia , Tachycardia, Ventricular , Ticlopidine , Ventricular FibrillationABSTRACT
BACKGROUND: Aspirin, one of the antiplatelet agents, improves the survival rate after myocardial infarction. This beneficial effect is known to be obtained in part by the antiarrhythmic action of aspirin. It is not known whether other antiplatelet agents have such effects. This study was performed to compare the effects of aspirin, ticlopidine, and abciximab (platelet glycoprotein IIb/IIIa receptor antagonist) on the ischemia-induced arrhythmias with a rat model of cardiac regional ischemia. METHODS: Experiments were performed in 4 groups of rats. The 4 groups were as follows : control, n=10:aspirin-pretreated, 300 mg/kg po for 1 week:ticlopidine-pretreated, 200 mg/kg po for 1 wk:abciximab-pretreated, 2 mg/kg iv 10-20 minutes before experiment. The electrocardiogram and blood pressure were recorded during 20 minutes. The time to the onset of ST-segment elevation and ventricular tachyarrhythmias, frequency and incidence of ventricular tachyarrhythmias, and death rate were assessed during acute myocardial ischemia induced by ligation of proximal left anterior descending coronary artery in anesthetized rats. RESULTS: Platelet aggregations to ADP were significantly lower in aspirin (42.8%), ticlopidine (43.8%), and abciximab group (34.0%) than in control group (66.4%). The frequencies of sustained ventricular tachycardia (VT) were 6.8+/-3.6 in control, 3.6+/-3.8 aspirin, 4.7+/-3.7 ticlopidine, and 1.4+/-2.5 abciximab group. The frequency of sustained VT in the abciximab group was significantly lower than in control group. The incidences of ventricular arrhythmias for 20 min were 10/10 for VT and 8/10 for ventricular fibrillation (VF) in control group, 7/10 for VT and 3/10 for VF in aspirin group, 10/10 for VT and 3/10 for VF in ticlopidine group, and 5/10 for VT and 4/10 for VF in abciximab group. The incidences of cardiac death during 20 min were 8/10 in control group, 4/10 in aspirin group, 2/10 in ticlopidine group and 5/10 in abciximab group. The incidence of VT in the abciximab group was significantly lower than in control group, incidences of VF in the aspirin and ticlopidine groups were significantly lower than in control group, and death rate in ticlopidine group was significantly lower than in control group. CONCLUSION: The present study suggested that aspirin, ticlopidine, and abciximab could prevent ventricular tachycardia or ventricular fibrillation in a rat model of cardiac regional ischemia and their antiarrhythmic effects improve the survival rate.
Subject(s)
Animals , Rats , Adenosine Diphosphate , Arrhythmias, Cardiac , Aspirin , Blood Platelets , Blood Pressure , Coronary Vessels , Death , Electrocardiography , Glycoproteins , Incidence , Ischemia , Ligation , Models, Animal , Mortality , Myocardial Infarction , Myocardial Ischemia , Platelet Aggregation Inhibitors , Survival Rate , Tachycardia , Tachycardia, Ventricular , Ticlopidine , Ventricular FibrillationABSTRACT
The aconite root has been used in oriental medicine to improve metabolism of debilitated patient and to cure acute dysuria, cardiac weakness, gout, neuralgias and rheumatism. The crude drug "bu-shi" or "cho-oh", which is obtained from the Aconitum roots, contains the potent poisons aconitine, mesaconitine, jesaconitine, and hypaconitine, which are C
Subject(s)
Adult , Humans , Aconitine , Aconitum , Alkaloids , Animal Experimentation , Arrhythmias, Cardiac , Dizziness , Dysuria , Gout , Hemodynamics , Medicine, East Asian Traditional , Metabolism , Nausea , Neuralgia , Poisons , Rheumatic Diseases , Shock , Tachycardia , Tachycardia, Ventricular , Torsades de Pointes , Ventricular Fibrillation , VomitingABSTRACT
The coronary vasospasm has usually been readily reversible by sublingual, intravenous or intracoronary nitroglycerin. Relief of spasm, either spontaneous or following nitrate therapy, results in reperfusion. Occurence of ventricular tachyarrhythmia during release of coronary spasm is attractive as a possible cause of sudden death because of significant proportion of sudden death victims do not have acute myocardial infarction. Recently, we experienced a 36 year old man who developed spontaneous coronary vasospasm, and the patients suffered from repetitive reperfusion ventricular tachyarrhythmia, and died suddenly in spite of administration of isosorbide dinitrate, lidocaine and several trials of cardioversion and cardiopulmonary resuscitation, and we report.