ajmaline and Tachycardia--Ventricular

Sodium channel blocker (SCB) infusion is used to unmask the electrocardiographic pattern of Brugada syndrome. The test may also induce premature ventricular complexes (PVCs) in individuals without Brugada pattern, the clinical relevance of which is little known.. The purpose of this study was to describe the prevalence of short-coupled (Sc) PVCs induced by ajmaline or flecainide in patients with suspected or documented severe ventricular arrhythmias.. We reviewed the SCB tests performed in 335 patients with suspected ventricular arrhythmias and structurally normal hearts in 9 centers. ScPVCs were defined as frequent and repetitive PVCs with an R-on-T pattern on SCB tests. Repeated SCB tests were performed in 7 patients and electrophysiological mapping of ScPVCs in 9.. Sixteen patients (8 men; mean age 36 ± 11 years) showed ScPVCs and were included. ScPVCs appeared 229 ± 118 seconds after the initiation of infusion and displayed coupling intervals of 288 ± 28 ms. ScPVC patterns were monomorphic in 12 patients, originating from the Purkinje system in mapped patients. Repetitive PVCs were induced in 15 patients (94%) including polymorphic ventricular tachycardias in 9 (56%). SCB infusion was repeated 45 (interquartile range 0.6-46) months later and induced identical ScPVC in all. SCB test was the only mean to reveal the malignant arrhythmia in 6 patients. Catheter ablation was performed in 9 patients, resulting in arrhythmia elimination in 8 with a follow-up of 6 (interquartile range 2-9) years.. SCB can induce ScPVC, mostly from Purkinje tissue, in a small subset of patients with idiopathic ventricular arrhythmias. Its high reproducibility suggests a distinct individual mechanism.

Topics: Adult; Ajmaline; Catheter Ablation; Electrocardiography; Flecainide; Humans; Male; Middle Aged; Reproducibility of Results; Sodium Channel Blockers; Tachycardia, Ventricular; Ventricular Premature Complexes

Pharmacologic challenge with sodium channel blockers is part of the diagnostic workout in patients with suspected Brugada syndrome. The test is overall considered safe but both ajmaline and flecainide detain well known pro-arrhythmic properties. Moreover, the treatment of patients with life-threatening arrhythmias during these diagnostic procedures is not well defined. Current consensus guidelines suggest to adopt cautious protocols interrupting the sodium channel blockers as soon as any ECG alteration appears. Nevertheless, the risk of life-threatening arrhythmias persists, even adopting a safe and cautious protocol and in absence of major arrhythmic risk factors. The authors revise the main published case studies of sodium channel blockers challenge in adults and in children, and summarize three cases of untreatable ventricular arrhythmias discussing their management. In particular, the role of advanced cardiopulmonary resuscitation with extra-corporeal membrane oxygenation is stressed as it can reveal to be the only reliable lifesaving facility in prolonged cardiac arrest.

Topics: Action Potentials; Adolescent; Adult; Aged; Aged, 80 and over; Ajmaline; Brugada Syndrome; Cardiopulmonary Resuscitation; Child; Electrocardiography; Extracorporeal Membrane Oxygenation; Female; Flecainide; Heart Arrest; Heart Conduction System; Heart Rate; Humans; Male; Middle Aged; Predictive Value of Tests; Risk Factors; Sodium Channel Blockers; Tachycardia, Ventricular; Treatment Outcome; Ventricular Fibrillation; Young Adult

The Brugada syndrome is a genetic disease characterized by an abnormal electrocardiogram (ECG) and an elevated risk of sudden cardiac death. Sodium channel blockers (SCBs), such as ajmaline, are used to unmask the characteristic type 1 Brugada electrocardiographic pattern. We review the literature on the incidence of ventricular arrhythmia (VA) during SCB challenge. We evaluate the clinical and electrocardiographic characteristics of these patients as well as their prognosis. All articles published from January 2000 until August 2015, in which the incidence and predictors of VAs during SCB challenge were reported, are reviewed. The occurrence of VA during SCB challenge ranges from 0 to 17.8%. The weighted average for induction of any VA during sodium blocking challenge is 2.4%; for non-sustained ventricular tachycardia (VT), it is 0.34% and for sustained VT 0.59%. No fatal cases were reported. Predictors may be young age, conduction disturbance at baseline ECG, and mutations in the SCN5A gene. All other clinical and electrocardiographic characteristics failed to be consistent predictors. Life-threatening arrhythmias during SCB challenge are not an exceptional event. Therefore, provocation testing must necessarily be performed in an appropriate environment in which advanced life support facilities are present. Patients who have a higher risk for induced arrhythmias might be those who display a conduction disturbance at baseline ECG or have certain SCN5A mutations or are of a younger age. However, survivors of these induced arrhythmias do not seem to suffer from a worse prognosis.

Topics: Ajmaline; Brugada Syndrome; Death, Sudden, Cardiac; Electrocardiography; Humans; Incidence; Mutation; NAV1.5 Voltage-Gated Sodium Channel; Risk Factors; Tachycardia, Ventricular; Voltage-Gated Sodium Channel Blockers

We report on a youngster followed by his paediatrician from birth until 14 years of age for premature beats, most likely of ventricular origin. The sudden death of his sister provoked a re-assessment of his electrocardiograms (ECG), resulting in the diagnosis of Brugada syndrome and the subsequent implantation of a cardioverter defibrillator. This syndrome is a well known entity in adult cardiology, first described by Brugada and Brugada in 1992. It is considered to be the second most common cause of death in young adults after road traffic accidents. In children, however, the Brugada syndrome is not well known and we believe to be certainly underdiagnosed.

Topics: Adolescent; Adult; Ajmaline; Brugada Syndrome; Death, Sudden; Defibrillators, Implantable; Electrocardiography; Female; Humans; Male; Siblings; Sodium Channel Blockers; Tachycardia, Ventricular

The diagnostic type I ECG in Brugada syndrome (BS) is often concealed and fluctuates between the diagnostic and non-diagnostic pattern. Challenge with intravenous ajmaline is used to unmask the diagnostic Brugada ECG. The aim of this study was to evaluate the safety of the test and to identify predictors for the response to an intravenous ajmaline challenge.. In four tertiary referral centres, 677 consecutive patients underwent an intravenous ajmaline challenge for diagnosis or exclusion of BS in accordance with the recommendations of the Brugada consensus conferences. Two hundred and sixty-two ajmaline challenges (39%) were positive. Male gender, familial BS, sudden cardiac arrest (SCA), first-degree AV-block, basal saddleback type ECG, and basal right bundle branch block were identified as predictors for a positive ajmaline challenge. A predictor for negative ajmaline test was the absence of ST-segment elevation at baseline. Six of 12 patients who had experienced SCA, and five of 25 patients with a familial sudden death exhibited a positive response to ajmaline. Only one patient (0.15%) developed sustained ventricular tachyarrhythmias (ventricular fibrillation) during ajmaline challenge, which was terminated by a single external defibrillator shock.. Ajmaline challenge is a safe procedure to unmask the electrocardiographic pattern of BS. Electrocardiographic and clinical parameters were identified to predict patients' response to ajmaline. The results of this study guide the clinician in which setting an ajmaline challenge is an appropriate diagnostic step.

Topics: Adult; Ajmaline; Anti-Arrhythmia Agents; Brugada Syndrome; Electrocardiography; Female; France; Germany; Humans; Injections, Intravenous; Male; Reproducibility of Results; Sensitivity and Specificity; Tachycardia, Ventricular

Abnormal delayed electrograms (EGMs) from the anterior wall of the right ventricular outflow tract (RVOT) epicardium have become the ablation target in Brugada syndrome (BrS).. The aim of this study was to analyze the safety, feasibility, and efficacy of a novel hybrid thoracoscopic approach to perform epicardial RVOT radiofrequency ablation in BrS.. Thirty-six patients with BrS (26 men (72.2%); mean age 36.6±15.8 years; range 3-63 years) who underwent hybrid thoracoscopic epicardial ablation of RVOT from January 2016 to April 2018 were included in this study. Two expert electrophysiologists analyzed the EGMs during ajmaline challenge and guided the surgeon to perform ablation. Ajmaline challenge was repeated after 1 month to assess the absence of the BrS electrocardiographic pattern. Patients were followed by remote monitoring and outpatient visits every 6 months.. The elimination of all abnormal EGMs was achieved in 94.4% of patients. After a mean follow-up of 16 ± 8 months (range 6-30 months), freedom from ventricular arrhythmias was obtained in 7 (77.8%) patients in secondary prevention 9/36 (25%) and in 24 (100%) patients in primary prevention 24/36 (75%). Major complications were observed in 1 patient (2.8%), who experienced late cardiac tamponade.. Hybrid thoracoscopic epicardial RVOT ablation in BrS is a safe and feasible approach, allowing direct visualization of ablation during radiofrequency delivery. Because of ventricular arrhythmia recurrences, implantable cardioverter-defibrillator implantation is still mandatory in patients treated in secondary prevention and with high risk.

Topics: Adult; Ajmaline; Anti-Arrhythmia Agents; Brugada Syndrome; Cardiac Tamponade; Catheter Ablation; Electrophysiologic Techniques, Cardiac; Feasibility Studies; Female; Heart Ventricles; Humans; Male; Pericardium; Postoperative Complications; Recurrence; Risk Adjustment; Tachycardia, Ventricular; Thoracic Surgery, Video-Assisted

Brugada syndrome (BrS) is associated with a pronounced risk to develop sudden cardiac death (SCD). Up to 21% of patients are related to mutations in SCN5A. Studies identified SCN10A as a contributor of BrS. However, the investigation of the human cellular phenotype of BrS in the presence of SCN10A mutations remains lacking. The objective of this study was to establish a cellular model of BrS in presence of SCN10A mutations using human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs).. Dermal fibroblasts obtained from a BrS patient suffering from SCD harbouring the SCN10A double variants (c.3803G>A and c.3749G>A) and three independent healthy control subjects were reprogrammed to hiPSCs. Human-induced pluripotent stem cells were differentiated into cardiomyocytes (hiPSC-CMs).The hiPSC-CMs from the BrS patient showed a significantly reduced peak sodium channel current (INa) and a significantly reduced ATX II (sea anemone toxin, an enhancer of late INa) sensitive as well as A-887826 (a blocker of SCN10A channel) sensitive late sodium channel current (INa) when compared with the healthy control hiPSC-CMs, indicating loss-of-function of sodium channels. Consistent with reduced INa the action potential amplitude and upstroke velocity (Vmax) were significantly reduced, which may contribute to arrhythmogenesis of BrS. Moreover, Ajmaline effects on action potentials were stronger in BrS-hiPSC-CMs than in healthy control cells. This is in agreement with the higher susceptibility of patients to sodium channel blocking drugs in unmasking BrS.. Patient-specific hiPSC-CMs are able to recapitulate single-cell phenotype features of BrS with SCN10A mutations and may provide novel opportunities to further elucidate the cellular disease mechanism.

Topics: Action Potentials; Ajmaline; Brugada Syndrome; Cardiotonic Agents; Case-Control Studies; Cellular Reprogramming Techniques; Cnidarian Venoms; Death, Sudden, Cardiac; Humans; Induced Pluripotent Stem Cells; Loss of Function Mutation; Male; Middle Aged; Morpholines; Mutation; Myocytes, Cardiac; NAV1.8 Voltage-Gated Sodium Channel; Niacinamide; Patch-Clamp Techniques; Phenotype; Tachycardia, Ventricular; Voltage-Gated Sodium Channel Blockers

There is emerging evidence that localization and elimination of abnormal electric activity in the epicardial right ventricular outflow tract may be beneficial in patients with Brugada syndrome.. In Brugada syndrome, AES is commonly located in the right ventricle epicardium and ajmaline exposes its extent and distribution, which is correlated with the degree of coved ST-elevation. AES elimination by radiofrequency ablation results in ECG normalization and VT/VF noninducibility. Substrate-based ablation is effective in potentially eliminating the arrhythmic consequences of this genetic disease.. URL: https://clinicaltrials.gov. Unique identifier: NCT02641431.

Topics: Action Potentials; Adolescent; Adult; Aged; Ajmaline; Anti-Arrhythmia Agents; Brugada Syndrome; Catheter Ablation; Death, Sudden, Cardiac; Defibrillators, Implantable; Electric Countershock; Electrocardiography; Electrophysiologic Techniques, Cardiac; Female; Heart Rate; Humans; Male; Middle Aged; Predictive Value of Tests; Prospective Studies; Tachycardia, Ventricular; Treatment Outcome; Ventricular Fibrillation; Young Adult

Topics: Ajmaline; Anti-Arrhythmia Agents; Brugada Syndrome; Catheter Ablation; Electrocardiography; Humans; Tachycardia, Ventricular; Ventricular Fibrillation

Topics: Ajmaline; Anti-Arrhythmia Agents; Brugada Syndrome; Catheter Ablation; Defibrillators, Implantable; Epicardial Mapping; Humans; Male; Middle Aged; Tachycardia, Ventricular

We present a case of a symptomatic patient with Brugada syndrome, who had sustained right ventricular outflow tract tachycardia after pronounced exercise-induced ST segment elevation in V

Topics: Ajmaline; Anti-Arrhythmia Agents; Brugada Syndrome; Catheter Ablation; Electrocardiography; Heart Conduction System; Humans; Male; Metaproterenol; Middle Aged; Stimulation, Chemical; Tachycardia, Ventricular; Treatment Outcome

Sudden arrhythmic death syndrome defines a sudden unexpected and unexplained death despite comprehensive pathological and toxicological investigation. Previous studies have focused on evaluation of adult relatives. There is, however, a lack of data in children, leading to highly variable management. We sought to determine the clinical utility of cardiac evaluation in pediatric relatives of sudden arrhythmic death syndrome probands.. Retrospective review was undertaken of pediatric patients with a family history of sudden arrhythmic death syndrome assessed from 2010 to 2013 in 2 centers. Clinical history, cardiac, and genetic investigations were assessed, including diagnoses made after evaluation of adult relatives. A total of 112 pediatric relatives from 61 families were evaluated (median age at presentation, 8 years; range, 0.5-16 years). A probable diagnosis was made in 18 (29.5%) families: Brugada syndrome, 13/18 (72%); long QT syndrome, 3/18 (17%); and catecholaminergic polymorphic ventricular tachycardia, 2/18 (11%). Genetic testing identified mutations in 20% of Brugada syndrome (2/10) and 50% of long QT syndrome (1/2) and catecholaminergic polymorphic ventricular tachycardia families (1/2) who were tested. Pediatric evaluation diagnosed 6/112 relatives (5.4%), increasing to 7% (6/85) if only first-degree relatives were assessed. The only useful diagnostic tests were the 12-lead and exercise electrocardiograms and ajmaline provocation test. The median duration of follow-up was 2.1 years (range, 0.2-8.2 years) with no cardiac events.. The yield of evaluating pediatric relatives is significant and higher when focused on first-degree relatives and on conditions usually expressed in childhood. We propose a management pathway for these children.

Topics: Adolescent; Adult; Age Factors; Ajmaline; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Brugada Syndrome; Child; Child, Preschool; Death, Sudden, Cardiac; Electrocardiography; Female; Genetic Predisposition to Disease; Genetic Testing; Humans; Infant; London; Long QT Syndrome; Male; Middle Aged; Pedigree; Phenotype; Predictive Value of Tests; Prognosis; Retrospective Studies; Risk Factors; Tachycardia, Ventricular; Time Factors; Young Adult

Topics: Ajmaline; Brugada Syndrome; Cardiovascular Diseases; Child; Feasibility Studies; Humans; Tachycardia, Ventricular

Sustained ventricular arrhythmias (sVAs), such as polymorphic ventricular tachycardia or ventricular fibrillation, can complicate ajmaline challenge in patients with Brugada syndrome (BS).. To assess the incidence of life-threatening sVAs during ajmaline administration in a large series of patients with BS. In addition, clinical characteristics as well as prognosis of these patients were evaluated.. All consecutive patients with ajmaline-induced diagnosis of BS were eligible for this study.. A total of 503 patients were included. Nine (1.8%) patients (44% men; mean age 26 ± 18 years) developed a life-threatening sVA during ajmaline challenge. Three patients (33%)were children, and 2 (22%) patients experienced sVAs refractory to the first external defibrillation. One patient underwent venoarterial extracorporeal membrane oxygenation to restore sinus rhythm. Age at the time of ajmaline challenge was significantly lower in patients with sVAs compared with patients without sVAs (26 ± 18 years vs 41 ± 18 years; P = .01). Moreover, patients with sVAs presented more frequently with sinus node dysfunction compared with patients with normal response to ajmaline (22.2% vs 1.4%; P = .01). After a mean follow-up time of 29 ± 8 months, none of the patients who had developed a sVA during ajmaline challenge died suddenly or developed further life-threatening ventricular arrhythmias.. sVA during ajmaline challenge is not a rare event in BS occurring in 9 (1.8%) patients. Despite its challenging acute treatment, the occurrence of ajmaline-induced sVAs in patients with BS might not identify a category at higher risk for further arrhythmic events.

Topics: Adolescent; Adult; Ajmaline; Anti-Arrhythmia Agents; Belgium; Brugada Syndrome; Child; Dose-Response Relationship, Drug; Electrocardiography; Female; Follow-Up Studies; Humans; Incidence; Injections, Intravenous; Male; Middle Aged; Prognosis; Prospective Studies; Risk Factors; Survival Rate; Tachycardia, Ventricular; Time Factors; Young Adult

A 44-year-old male patient admitted with palpitations was diagnosed with tachycardia with wide QRS, but recovered after being treated with amiodarone. The patient's coronary angiography was normal. As the patient's resting ECG was compatible with Brugada type 2, an ajmaline challenge test was scheduled. The infusion procedure was suspended following an observation of type 1 ECG findings in the 4th minute of infusion. Approximately 10-15 seconds later, a monomorphic ventricular tachycardia with a rate of 150 beats/minute developed. In the follow-up, the patient's heartbeat returned spontaneously to the sinus rhythm within 3-4 minutes. Polymorphic ventricular tachycardia or ventricular fibrillation tachyarrhythmias usually result in syncope or sudden cardiac death in cases of Brugada syndrome, while monomorphic tachycardia, as in our case, is rare. Here, we present a rare case of monomorphic ventricular tachycardia, which was observed during the ajmaline challenge test.

Topics: Adult; Ajmaline; Amiodarone; Anti-Arrhythmia Agents; Electrocardiography; Humans; Male; Tachycardia, Ventricular

We report the case of a very prolonged spontaneous episode of self-terminating ventricular fibrillation in a patient with Brugada syndrome (BrS). The patient first underwent implantation of an internal loop recorder after an episode of prolonged loss of consciousness (several minutes) that was suggestive of a nonarrhythmic cause. After a second episode of prolonged syncope, subsequent interrogation of the loop recorder revealed a very prolonged episode of self-terminating ventricular arrhythmia, lasting 2 minutes and 41 seconds. This short report emphasizes the fact that an arrhythmic cause of syncope should not be ruled out in patients with BrS presenting with very prolonged loss of consciousness.

Topics: Administration, Oral; Adult; Ajmaline; Anti-Arrhythmia Agents; Brugada Syndrome; Defibrillators, Implantable; Electrocardiography; Follow-Up Studies; Humans; Male; Quinidine; Signal Processing, Computer-Assisted; Tachycardia, Ventricular; Unconsciousness; Ventricular Fibrillation

Early graft failure after CABG surgery may lead to severe adverse events and death. Because the cause of the graft failure can vary, rapid diagnostic management is mandatory in order to address these complications appropriately. In the present 2 cases, patients who underwent CABG procedures showed typical electrocardiograms and serology of a perioperative myocardial ischemia shortly after surgery. In the first case, a rapidly performed coronary angiogram revealed a torqued right CABG, which was detorqued and, in order to avoid further torsion, fixated to the pericardium in a redo procedure. In the second case, the patient underwent a revascularization by means of percutaneous coronary intervention with stent implantation for severe stenosis due to a localized dissection of the vein graft, diagnosed on coronary angiogram. The further postoperative course of both patients was smooth and both could be discharged on day 8 and 11 after initial surgery, respectively.

Topics: Aged; Ajmaline; Amiodarone; Anti-Arrhythmia Agents; Coronary Artery Bypass; Coronary Artery Disease; Female; Humans; Male; Tachycardia, Ventricular; Treatment Outcome

The present study investigated whether several ECG markers of ventricular repolarization are associated with ventricular tachycardia/fibrillation (VT/VF) inducibility in subjects with type 1 ECG pattern of Brugada syndrome (BS).. The clinical data of 23 individuals (19 males, age 42.69 +/- 14.63) with spontaneous (n = 10) or drug-induced (n = 13) type 1 ECG pattern of BS who underwent programmed ventricular stimulation were analysed. Sustained VT/VF was induced in 17 subjects (74%) and was significantly associated with the presence of spontaneous type 1 ECG of BS (P = 0.012). Among the studied ECG repolarization markers, subjects with inducible VT/VF displayed an increased T(peak)-T(end) interval in leads V(2) (88.82 +/- 15.70 vs. 78.33 +/- 4.08 ms, P = 0.02) and V(6) (76.33 +/- 10.08 vs. 66.66 +/- 5.16 ms, P = 0.04) and a greater T(peak)-T(end)/QT ratio in lead V(6) (0.214 +/- 0.028 vs. 0.180 +/- 0.014, P = 0.009) compared with those without arrhythmias. Ventricular tachycardia/fibrillation inducibility was not associated with arrhythmic events during a mean follow-up period of 4.61 +/- 2.14 years (P = 0.739).. The T(peak)-T(end) interval and T(peak)-T(end)/QT ratio were associated with VT/VF inducibility in BS. The utility of T(peak)-T(end)/QT ratio as a new marker of arrhythmogenesis in BS requires further studies, including a large number of patients.

Topics: Adult; Ajmaline; Anti-Arrhythmia Agents; Biomarkers; Brugada Syndrome; Electrocardiography; Female; Flecainide; Heart Conduction System; Humans; Male; Middle Aged; Predictive Value of Tests; Retrospective Studies; Risk Factors; Tachycardia, Ventricular; Ventricular Fibrillation

Topics: Adult; Ajmaline; Anti-Arrhythmia Agents; Brugada Syndrome; Electrocardiography; Female; France; Germany; Humans; Injections, Intravenous; Male; Reproducibility of Results; Sensitivity and Specificity; Tachycardia, Ventricular

A 24-year-old man without structural heart disease was admitted following recurrent syncopes. His baseline ECG revealed a right bundle-branch block (RBBB) pattern. Spontaneous monomorphic and polymorphic ventricular tachycardias (VT) were observed during monitoring. The provocation test by propafenone brought out recurrent spontaneous polymorphic VT and provocation by ajmaline caused an ST elevation in V2. Programmed ventricular stimulation test during the electrophysiologic study revealed both monomorphic and polymorphic VT. The patient received an internal cardioverter/defibrillator with the diagnosis of Brugada syndrome.

Topics: Adult; Ajmaline; Anti-Arrhythmia Agents; Brugada Syndrome; Bundle-Branch Block; Defibrillators, Implantable; Electrocardiography; Humans; Male; Propafenone; Tachycardia, Ventricular

An association between arrhythmogenic right ventricular dysplasia-cardiomyopathy (ARVD/C) and Brugada syndrome can be supposed according to several case reports. In order to examine a possible link between ARVD/C and Brugada syndrome, systematic ajmaline testing with 1 mg/kg body weight intravenously, was done in 55 patients (32 males, mean age 46.7+/-12.3 years) with ISFC/ESC criteria of ARVD/C. In nine patients ajmaline testing could demonstrate coved ST segment elevation of at least 2 mm in at least two right precordial leads. Three of these patients had recurrent syncopes. Electrophysiological study revealed non-sustained ventricular tachycardia with left bundle branch block configuration and inferior axis in only one case. Systematic ajmaline testing could demonstrate a definite link between ARVD/C and Brugada syndrome.

Topics: Adult; Aged; Ajmaline; Anti-Arrhythmia Agents; Arrhythmogenic Right Ventricular Dysplasia; Bundle-Branch Block; Electrocardiography; Female; Germany; Humans; Male; Middle Aged; Prevalence; Syncope; Syndrome; Tachycardia, Ventricular

The Brugada syndrome is an arrhythmogenic disease caused in part by mutations in the cardiac sodium channel gene, SCN5A. The electrocardiographic pattern characteristic of the syndrome is dynamic and is often absent in affected individuals. Sodium channel blockers are effective in unmasking carriers of the disease. However, the value of the test remains controversial.. We studied 147 individuals representing 4 large families with SCN5A mutations. Of these, 104 were determined to be at possible risk for Brugada syndrome and underwent both electrocardiographic and genetic evaluation. Twenty-four individuals displayed an ECG diagnostic of Brugada syndrome at baseline. Of the remaining, 71 received intravenous ajmaline. Of the 35 genetic carriers who received ajmaline, 28 had a positive test and 7 a negative ajmaline test. The sensitivity, specificity, and positive and negative predictive values of the drug challenge were 80% (28:35), 94.4% (34:36), 93.3% (28:30), and 82.9% (34:41), respectively. Penetrance of the disease phenotype increased from 32.7% to 78.6% with the use of sodium channel blockers. In the absence of ST-segment elevation under baseline conditions, a prolonged P-R interval, but not incomplete right bundle-branch block or early repolarization patterns, indicates a high probability of an SCN5A mutation carrier.. In families with Brugada syndrome, the data suggest that ajmaline testing is valuable in the diagnosis of SCN5A carriers. In the absence of ST-segment elevation at baseline, family members with first-degree atrioventricular block should be suspected of carrying the mutation. An ajmaline test is often the key to making the proper diagnosis in these patients.

Topics: Ajmaline; Electrocardiography; Female; Genetic Testing; Heart Block; Heterozygote; Humans; Male; NAV1.5 Voltage-Gated Sodium Channel; Pedigree; Risk; Sensitivity and Specificity; Sodium Channel Blockers; Sodium Channels; Syndrome; Tachycardia, Ventricular

Ajmaline, a reserpine derivative, is an effective class I antiarrhythmic agent. Herein we report two cases of ajmaline-induced abnormal QT prolongation accompanied by polymorphic ventricular tachycardia of the torsade de pointes type. Since ajmaline is increasingly used for the acute termination of wide complex tachycardia and as a diagnostic tool after syncope and in patients with idiopathic ventricular tachyarrhythmias, our observations suggest that caution should be exercised with regard to the effects of the drug on the QT interval and its potency to induce proarrhythmia of the torsade de pointes type.

Topics: Ajmaline; Anti-Arrhythmia Agents; Atrial Flutter; Electrocardiography; Female; Humans; Long QT Syndrome; Male; Middle Aged; Tachycardia; Tachycardia, Ventricular; Torsades de Pointes

We present the case of a 13-year-old boy with an episode of aborted sudden death, absence of structural heart disease, and a characteristic ECG pattern of right bundle branch block with persistent ST-segment elevation in the right precordial leads, in whom a monomorphic sustained ventricular tachycardia developed spontaneously after the administration of ajmaline. This effect may be related to an increased inhomogeneity of repolarization mediated by the drug and demonstrates the arrhythmogenic potential of Class I antiarrhythmic drugs in patients with Brugada syndrome.

Topics: Adolescent; Ajmaline; Anti-Arrhythmia Agents; Bundle-Branch Block; Electrocardiography; Humans; Male; Syndrome; Tachycardia, Ventricular; Ventricular Fibrillation

We report a case of tachycardia due to reentry within the His-Purkinje system (HPS) occurring after introduction of flecainide. The patient presented with a mild mitral regurgitation and normal left ventricular function. He had incomplete left bundle branch block with left-axis deviation. At the electrophysiology study, a prolonged HV interval was observed at baseline, and the tachycardia could be reproduced after ajmaline infusion. Six months after interruption of flecainide, the patient remains free of arrhythmia recurrence. The authors emphasize that proarrhythmic effects of flecainide may include reentry within the HPS in patients with underlying HPS disease.

Topics: Administration, Oral; Aged; Ajmaline; Anti-Arrhythmia Agents; Bundle of His; Bundle-Branch Block; Electrocardiography; Female; Flecainide; Humans; Infusions, Intravenous; Purkinje Fibers; Tachycardia, Ventricular

A 48-year-old patient with recurrent episodes of palpitations and syncope presented with transient ST segment elevation in the right precordial ECG leads. Structural heart disease was excluded. No arrhythmias were inducible by programmed ventricular stimulation. Parallel to ST elevation after intravenous ajmaline, a gradual and reversible delay in the upstroke of right ventricular (RV) monophasic action potentials (MAPs) occurred that was most marked in the RV outflow tract and nearly absent at right free-wall recordings. Ajmaline led to a cycle length-dependent increase in RV dispersion of repolarization. Thus, right endocardial MAPs may demonstrate regionally different action potential changes that may contribute to the ECG changes in Brugada syndrome.

Topics: Action Potentials; Ajmaline; Anti-Arrhythmia Agents; Defibrillators, Implantable; Electrocardiography; Female; Follow-Up Studies; Humans; Injections, Intravenous; Middle Aged; Syndrome; Tachycardia, Ventricular; Ventricular Fibrillation; Ventricular Function, Right

As yet the antiarrhythmic efficacy of ajmaline with regard to suppressing the induction of sustained ventricular tachycardia after myocardial infarction has not been determined. Therefore, programmed electrical stimulation was performed in 8 conscious, chronically instrumented mongrel dogs 8-20 days after a 4-hour occlusion of the left anterior descending coronary artery. At baseline all animals responded with sustained ventricular tachycardia. Thereafter, ajmaline was administered at two consecutive i.v. doses: a bolus of 0.7 mg kg-1 followed by infusion of 2 mg kg-1 h-1 and infusion of 4 mg kg-1 h-1. The induction of sustained ventricular tachycardia was prevented in 2/8 animals by 2 mg kg-1 h-1 ajmaline and in 1/8 animals by 4 mg kg-1 h-1 ajmaline. During sinus rhythm only 4 mg kg-1 h-1 ajmaline significantly increased QRS-duration and intraventricular activation times, but during rapid right ventricular pacing (cycle length = 330 ms) both doses of ajmaline increased QRS duration and intraventricular conduction times. 4 mg kg-1 h-1 ajmaline also increased the cycle length of induced sustained ventricular tachycardia. In 3 animals induction of sustained ventricular tachycardia during infusion of 4 mg kg-1 h-1 ajmaline was achieved by introduction of less extrastimuli than at baseline. Furthermore the coupling intervals of extrastimuli that induced sustained ventricular tachycardia were substantially prolonged by this dose. Inhomogeneity of conduction between left ventricular normal zone and left ventricular infarct zone was significantly increased by 4 mg kg-1 h-1 ajmaline during rapid right ventricular pacing, but not during sinus rhythm.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Ajmaline; Animals; Anti-Arrhythmia Agents; Cardiac Complexes, Premature; Coronary Vessels; Dogs; Electric Stimulation; Electrophysiology; Female; Heart Conduction System; Male; Myocardial Infarction; Myocardial Reperfusion; Tachycardia, Ventricular

Topics: Ajmaline; Alkaloids; Humans; Rauwolfia; Tachycardia; Tachycardia, Paroxysmal; Tachycardia, Ventricular

Topics: Ajmaline; Drug Therapy; Electrocardiography; Humans; Myocardial Infarction; Rauwolfia; Tachycardia; Tachycardia, Ventricular

Topics: Ajmaline; Pacemaker, Artificial; Procainamide; Rauwolfia; Tachycardia; Tachycardia, Paroxysmal; Tachycardia, Ventricular; Therapeutics

Topics: Ajmaline; Myocardial Infarction; Rauwolfia; Tachycardia; Tachycardia, Paroxysmal; Tachycardia, Ventricular