Torsades de pointes short-coupling

A 10-month-old infant experienced cardiac arrest caused by ventricular fibrillation (VF). His electrocardiogram (ECG) at rest was within the normal range. Amiodarone was indispensable due to its refractoriness to defibrillation. After implantable cardioverter defibrillator (ICD) implantation, ICD shock was delivered. ICD recordings documented VF and ventricular tachycardia (VT) triggered by premature ventricular contractions with an extremely short coupling interval (240 ms), which were controlled by verapamil...

We present a case of sudden cardiac arrest 7 hours after radiofrequency ablation of the atrioventricular junction for symptomatic permanent atrial fibrillation unresponsive to medical therapy. The Holter monitoring revealed a progressive increasing of QT interval after the procedure, highlighting the repolarization instability after acute changes in heart rates associated with modification of ventricular activation, leading to occurrence of short coupling interval ventricular extra beats and finally to a "torsade de pointes...

BACKGROUND: Ventricular fibrillation may be caused by premature ventricular contractions (PVCs) whose coupling intervals are <300 ms, a characteristic of the short-coupled variant of torsades de pointes (scTdP). OBJECTIVE: The purpose of this study was to analyze the underlying cardiac ryanodine receptor (RyR2) variants in patients with scTdP. METHODS: Seven patients with scTdP (mean age 34 ± 12 years; 4 men and 3 women) were enrolled in this study...

A 49-year-old woman, with no relevant family history, was admitted in 1996 for arrhythmic storm with polymorphic ventricular tachycardia (torsade de pointes) which degenerated into ventricular fibrillation. Iatrogenic causes were excluded, the electrocardiogram (ECG) was normal and there was no structural heart disease. She refused cardioverter-defibrillator implantation. Treatment was begun with amiodarone, which she took irregularly. She remained asymptomatic until 2014 when she was admitted for a new arrhythmic storm with torsade de pointes, refractory to antiarrhythmic therapy and aggravated by ventricular pacing (65 defibrillations)...

BACKGROUND: Acquired long QT syndrome (a-LQTS) is associated with life-threatening ventricular arrhythmias, mainly torsades de pointes (TdP). ECG parameters predicting evolving into ventricular fibrillation (VF) are ill defined. AIMS: To determine ECG parameters preceding and during TdP associated with higher risk of developing VF. METHODS: We analyzed 151 episodes of TdP, recorded in 28 patients with a-LQTS (mean QTc 638 ms ± 57). RESULTS: All 28 patients had prolonged QT interval, (mean QTc 638 ms ± 57) ranging from 502 ms to 858 ms correcting by Bazett's formula...

The polymorphic ventricular tachycardia (PVT) is uncommon arrhythmia with multiple causes and has been classified according to whether they are associated with long QT interval or normal QT. Whereas "Torsade de pointes (TdP)" is an uncommon and distinctive form of PVT occurring in a setting of prolonged QT interval, which may be congenital or acquired (congenital or acquired), "PVT with normal QT" is associated with myocardial ischemia, electrolyte abnormalities (hypokalemia), mutations of the cardiac sodium channel (Brugada syndrome), and the ryanodine receptor (catecholaminergic PVT)...

No abstract text is available yet for this article.

We describe 5 cases of a rare and often lethal arrhythmia: short-coupled variant of torsade de pointes. In the light of quitecharacteristic electrocardiograms and clinical picture of this arrhythmia, we consider the name 'short-coupled variant torsade de pointes' as more appropriate than, the more commonly applied term for such cases - 'idiopathic ventricular fibrillation'. We suggest that in patients with unexplained syncope, normal echocardiogram, normal QT interval and frequent premature ventricular contraction with short coupling this arrhythmogenic entity should be suspected...

No abstract text is available yet for this article.

Short-coupled variant of torsade de pointes (TdP) is an uncommon variant of polymorphic ventricular tachycardia with unknown etiology. It is initiated by a closely coupled premature ventricular complex (<300 ms) in the absence of QT prolongation and structural heart disease. Verapamil seems to be the only drug able to suppress the arrhythmia but, as it does not reduce the risk of sudden death, implantation of a cardioverter-defibrillator (ICD) is recommended. We describe the case of a 46-year-old woman referred to our Emergency Department because of palpitations...

Electrical storm (ES) presents a difficult management problem that has predominantly been described in adults and there are limited published data relating to children. We set out to characterize ES in children to assist management based on published literature and own institutional experience. We retrospectively analyzed the records of children presenting with ES to our institution between July 2001 and July 2011 and conducted a systematic literature review. Four children were identified (median age: 5.7 years, range: 3...

This case report describes incessant monomorphic ventricular tachycardia (VT), not torsade de pointes, induced by intravenous amiodarone in a 48-year-old woman with dilated cardiomyopathy. VT was reproducibly triggered by short coupled premature ventricular complex (PVC) with different morphology from VT. After amiodarone infusion, the coupling interval of initiating PVC was prolonged, and moreover, the morphology of initiating PVC became the same as that of VT. Though amiodarone has become the first line drug to treat ventricular tachyarrhythmias in patients with cardiac dysfunction, it is important to be aware of its proarrhythmic effect, which may lead to an electrical storm of monomorphic VT...

Chemotherapy has little impact on renal carcinoma. Interferon alfa is the standard treatment, in the absence of a better alternative, but the median survival time is less than a year among patients with advanced-stage or metastatic disease. Pazopanib inhibits multiple receptor tyrosine kinases, including the tyrosine kinase coupled to the vascular endothelial growth factor receptor (VEGFR), thus inhibiting angiogenesis. It is authorised in the European Union for the treatment of advanced-stage renal carcinoma...

During therapeutic hypothermia, QT interval is prolonged. In patients with congenital long QT syndrome (LQTs), a longer QT interval was associated with significantly increased risk of cardiac arrest (CA). Therefore, therapeutic hypothermia may have proarrhythmic effects in survivors of CA due to congenital LQTs. A 27-year-old man was resuscitated from CA due to congenital LQTs type 3 and Brugada syndrome. Torsade de pointes (TdP) recurred spontaneously on admission (body temperature, 36.9°C). During mild hypothermia therapy, QTc increased from 499 (36...

This 24-year-old woman had incessant polymorphic ventricular tachycardia (PVT) during week 24 of her pregnancy and received over 200 implantable cardioverter-defibrillator discharges. She failed to respond to quinidine, magnesium, isoproterenol, amiodarone, esmolol, and cilostazol during her PVT storm, although her dramatic response to verapamil was consistent with the diagnosis of short-coupled variant of torsades de pointes. The case illustrated the utility of extracorporeal membrane oxygenation during refractory PVT, while attempting diagnostic and therapeutic pharmacologic maneuvers...

Torsade de pointes (TdP), a ventricular tachycardia (VT) with the peaks of QRS complexes twisting around the iso-electric baseline and progressive amplitude and polarity variations, is mostly associated with long (congenital or acquired) QT syndromes (LQTS) and long coupling intervals of the initiating complex. We describe a patient with variant, short-coupled TdP, a normal QTc interval and without demonstrable structural heart disease. Mechanisms remain unclear but there may be a relationship with autonomic nervous system imbalance...

INTRODUCTION AND OBJECTIVES: The mechanisms that trigger ventricular fibrillation (VF) are poorly understood. The aim of this study was to analyze the initiation of VF in electrograms stored in implantable cardioverter-defibrillators (ICDs). METHODS: We analyzed ICD electrograms from patients who had suffered at least one episode of VF. RESULTS: Of 250 patients with ICDs, 13 (10 male and 3 female, age 49+/-22 years) had at least one episode of VF...

This report presents a patient with macrovolt T wave alternans, PVC with R on T or a long-short sequence followed by torsades de pointes.

Although a plethora of earlier studies focused on the histology and action potential characteristics of Purkinje fibers, only recently has the His-Purkinje system been found to play a major role in the genesis of cardiac arrhythmias. The anatomic complexity of the left ventricular conduction system appears to favor reentrant arrhythmias in both diseased and healthy hearts. Macroreentrant circuits between the right and left bundles as well as between the left ventricular fascicles are amenable to cure by ablative techniques...

This case report describes a 50-year-old woman with normal repolarization duration who survived multiple electrical storms and cardiac arrest related to recurrent short-coupled torsade de pointes (TdP). Overdrive ventricular pacing could not prevent malignant TdP, but exposed a pause-related TdP initiation pattern. Isoproterenol and atrial pacing completely suppressed TdP, suggesting that ventricular pacing may entail vulnerability to this condition.