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Background: This case highlights the management of concomitant acute myocarditis and congenital long QT syndrome with electrical storm and incessant Torsade de Pointes., Case Presentation: An 18 years-old Southeast Asian para 1 abortus 0 (P1A0) postpartum patient with cesarean section owing to severe preeclampsia, acute lymphocytic myocarditis, and prolonged QT interval owing to long QT syndrome. She has incessant Torsade de Pointes treated with beta-blocker, lidocaine, overdrive pacing with a temporary transvenous pacemaker, left cardiac sympathetic denervation per video-assisted thoracoscopic surgery, and implantable cardioverter-defibrillator implantation. We initially used bisoprolol, then switched to propranolol and finally to carvedilol, which reduced the Torsade de Pointes frequency. The longest QTc interval was 696 ms, and the shortest was 624 ms, 2 months after initial corticosteroid administration and left cardiac sympathetic denervation. Device interrogation at 9 months follow up showed three episodes of ventricular fibrillation, 2 spontaneously resolved and one necessitates shock., Conclusion: Management of concomitant acute myocarditis and congenital long QT syndrome with incessant Torsade de Pointes requires beta-blockers, anti-inflammatory drugs, autonomic modulation, and short-term measures, such as overdrive pacing with deep sedation. Implantable cardioverter-defibrillator is vital to prevent sudden cardiac death., Competing Interests: Declarations. Ethics approval and consent to participate: Not applicable. Consent for publication: Written informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal. Competing interests: None., (© 2024. The Author(s).)

Coronavirus disease 2019 (COVID-19) is associated with cardiovascular complications; however, Takotsubo cardiomyopathy (TCM) with QT prolongation and Torsade de pointes has been reported only rarely. We present a case of TCM after QT prolongation and Torsade de pointes. A 58-year-old woman was admitted because of COVID-19-related pneumonia. Seven days after admission, she developed sudden loss of consciousness without any indication of cardiovascular disease. A monitoring electrocardiogram indicated Torsade de pointes and a prolonged QT interval. Emergency cardiac catheterization revealed TCM. She was treated with favipiravir and steroids, followed by rehabilitation, and her condition improved. To detect asymptomatic TCM, routine electrocardiography screening should be considered for patients with COVID-19.

The obesity pandemic is becoming one of the most prevalent diseases nowadays. There is a wide spectrum of treatment, ranging from hygienic-dietary measures to bariatric surgery. Endoscopic intragastric balloon placement is becoming increasingly more frequent, due to its technical simplicity, safety and short-term success(1). Although complications are rare some can be severe, so pre-endoscopic evaluation must be carried out carefully. A 43-year-old woman with a history of grade I obesity (BMI 32.7) had an Orbera® intragastric balloon implanted successfully. After the procedure she presented frequent nausea and vomiting, partially controlled with antiemetics. She attended the Emergency Department(ED) with a persistent emetic syndrome - oral intolerance and short-term loss of consciousness(syncope), for which she was admitted. Lab tests showed metabolic alkalosis with severe hypokalemia(K+ 1.8mmol/L), so fluid therapy was initiated for hydroelectrolytic replacement. During the patient's stay in the ED, two episodes of polymorphic ventricular tachychardia "Torsades de Pointes" (PVT-TDP) occurred, leading to cardiac arrest and requiring electrical cardioversion to restore sinus rhythm, in addition to a temporary pacemaker placement. Telemetry showed a corrected QT interval of >500ms, compatible with Long QT Syndrome(LQTS). Once the patient was hemodynamically stabilized a gastroscopy was performed. The intragastric balloon located in the fundus was removed using an extraction kit, puncturing and aspirating 500ml of saline solution, and extracting the collapsed balloon without any complications. The patient achieved an adequate oral intake afterwards, and no recurrence of emetic episodes were noticed. Previous ECGs revealed a prolonged QT interval and a genetic study confirmed a congenital type 1 LQTS. Treatment was initiated with beta-blockers and a bicameral automatic defibrillator was implanted in order to prevent recurrences. Intragastric balloon placement is generally a safe procedure, serious complications present in 0.70% of cases(2). It is essential to have a proper pre-endoscopic evaluation, including patient's medical history and comorbidities. Episodes of PVT-TDP may present precipitated by certain medications (eg. metoclopramide) or hydroelectrolytic imbalances (eg, hypokalemia)(3). A standardized evaluation of ECG before intragastric balloon placement may be useful to prevent these rare but serious complications.

Összefoglaló. A szerzők egy 44 éves, autoimmun betegségben szenvedő nőbeteg kórlefolyását ismertetik. A váratlan kórházi kamrafibrillációt követő sikeres resuscitatio után a beteg comatosus állapotban maradt, ezért terápiás hypothermiában részesült. A hypothermiás kezelés hatására jelentős QT-megnyúlás és "torsade de pointes" kamrai tachycardia lépett fel. A hypothermia okozta szívritmuszavar oka a hőmérséklet-csökkenés kiváltotta QT-megnyúlás és korai utódepolarizációs mechanizmusú triggerelt aktivitás. A szerzők felhívják a figyelmet arra, hogy jelen tudásunk szerint enyhe hypothermiát javasolt alkalmazni az ajánlásban szereplő hypothermiás tartományon belül. Orv Hetil. 2022; 163(13): 523-526. Summary. The authors describe the course of disease in a 44-year-old female patient with autoimmune disease. After successful resuscitation following unexpected hospital ventricular fibrillation, the patient remained in a comatose state and therefore received therapeutic hypothermia. Hypothermic treatment resulted in significant QT prolongation and "torsade de pointes" ventricular tachycardia. The probable cause of arrhythmia is the QT prolongation caused by the hypothermia and the consequential early afterdepolarization and triggered activity. The authors draw attention to the fact that - to the best of our knowledge - milder hypothermia is recommended within the preset hypothermic range. Orv Hetil. 2022; 163(13): 523-526.

Background: This case demonstrates the severe electrolyte derangements that may present after a common therapy such as a bowel preparation for an outpatient procedure and the rare yet potential detrimental outcomes of those abnormalities. It also highlights the implications of long QT syndrome regarding pharmacology and treatment., Case Presentation: We present a case of 48 year-old female with severe electrolyte derangements and long QT syndrome (LQTS) leading to Torsades de Pointes (TdP), pulseless ventricular fibrillation, and unsynchronized defibrillation in the post anesthesia care unit (PACU) after uneventful upper and lower endoscopy. This led to an unanticipated intensive care unit admission for aggressive electrolyte repletion, cardiology consultation, and implantable cardioverter defibrillator (ICD) placement., Conclusions: This is a rare presentation after an outpatient procedure that would have had a detrimental outcome if not promptly diagnosed and treated appropriately. Therefore, we aim to provide further insight into the diagnosis and treatment of severe hypokalemia and long QT syndrome resulting in Torsades de Pointes and ventricular fibrillation., (© 2021. The Author(s).)

An 82-year-old woman was admitted to our hospital because of dyspnea and bradycardia during exertion. Electrocardiography revealed complete atrioventricular block. During pacemaker implantation, a small dose (12.5 mg) of hydroxyzine was injected for sedation, and torsade de pointes (Tdp) occurred. The QT interval was prolonged after administration of hydroxyzine, and Tdp was observed after the R on T phenomenon occurred, indicating that hydroxyzine was capable of prolonging the QT interval and causing Tdp. Therefore, we must be cautious when administering hydroxyzine for sedation during surgery, especially in patients with bradycardia.

Background: The coronavirus disease 2019 (COVID-19) pandemic has affected millions of people worldwide resulting in significant morbidity and mortality. Arrhythmias are prevalent and reportedly, the second most common complication. Several mechanistic pathways are proposed to explain the pro-arrhythmic effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. A number of treatment approaches have been trialled, each with its inherent unique challenges. This rapid systematic review aimed to examine the current incidence and available treatment of arrhythmias in COVID-19, as well as barriers to implementation., Methods: Our search of scientific databases identified relevant published studies from 1 January 2000 until 1 June 2020. We also searched Google Scholar for grey literature. We identified 1729 publications of which 1704 were excluded., Results: The incidence and nature of arrhythmias in the setting of COVID-19 were poorly documented across studies. The cumulative incidence of arrhythmia across studies of hospitalised patients was 6.9%. Drug-induced long QT syndrome secondary to antimalarial and antimicrobial therapy was a significant contributor to arrhythmia formation, with an incidence of 14.15%. Torsades de pointes (TdP) and sudden cardiac death (SCD) were reported. Treatment strategies aim to minimise this through risk stratification and regular monitoring of corrected QT interval (QTc)., Conclusion: Patients with SARS-CoV-2 are at an increased risk of arrhythmias. Drug therapy is pro-arrhythmogenic and may result in TdP and SCD in these patients. Risk assessment and regular QTc monitoring are imperative for safety during the treatment course. Further studies are needed to guide future decision-making., (© 2020 Stichting European Society for Clinical Investigation Journal Foundation. Published by John Wiley & Sons Ltd.)

Dofetilide, a class III antiarrhythmic, is widely used in the treatment of cardiac arrhythmias. Antiarrhythmic drugs can have a long duration of action that prolongs the QT interval. This causes bradycardia that predisposes to R-on-T phenomenon subsequently leading to torsades de pointes (TdP). This necessitates constant monitoring to prevent or treat ventricular arrhythmias or bradycardia associated with cardiac medications. Although extremely rare, dofetilide overdose has been described in the literature. However, no evidence found in the current literature required prolonged intervention after the initial acute stabilization, leading to scarcity of data for treatment of ongoing dofetilide overdose. We present the case of an intentional dofetilide overdose in a 61-year-old Caucasian woman with a history of congestive heart failure, atrial fibrillation, stage IIIb chronic kidney disease, diabetes mellitus type II, hypothyroidism, morbid obesity, and hypertension that required extensive interventions for refractory TdP that lasted 4 days. Therapeutic as well as excess dosage of dofetilide can lead to TdP, which is usually controlled by decreasing the dose or terminating drug administration. If the arrhythmia is not resolved, guidelines recommend management with activated charcoal if ingestion is within 15 minutes, followed by administration of 2 g IV (intravenous) magnesium and addressing the electrolyte imbalance. However, if the arrhythmia is persistent due to ongoing dofetilide toxicity, isoproterenol is given as a bridge to overdrive pacing and dopamine is used as an alternative to isoproterenol.

Human-induced pluripotent stem cell (iPSC) technology paves the way for next-generation drug-safety assessment. In particular, human iPSC-derived cardiomyocytes, which exhibit electrical activity, are useful as a human cell model for assessing QT-interval prolongation and the risk of the lethal arrhythmia Torsade de Pointes (TdP). In addition to proarrhythmia assay, contractile behavior has received increased attention in drug development. In this study, we developed a novel high-throughput in vitro assay system using motion vectors to evaluate the contractile activity of iPSC-derived cardiomyocytes as a physiologically relevant human platform. The methods presented here highlight the use of commercially available iPSC-derived cardiomyocytes, iCell cardiomyocytes, for contractility evaluation recorded by the motion vector system., (© 2021. Springer Science+Business Media, LLC, part of Springer Nature.)

As the coronavirus disease 19 (COVID-19) global pandemic rages across the globe, the race to prevent and treat this deadly disease has led to the "off-label" repurposing of drugs such as hydroxychloroquine and lopinavir/ritonavir, which have the potential for unwanted QT-interval prolongation and a risk of drug-induced sudden cardiac death. With the possibility that a considerable proportion of the world's population soon could receive COVID-19 pharmacotherapies with torsadogenic potential for therapy or postexposure prophylaxis, this document serves to help health care professionals mitigate the risk of drug-induced ventricular arrhythmias while minimizing risk of COVID-19 exposure to personnel and conserving the limited supply of personal protective equipment., (Copyright © 2020. Published by Elsevier Inc.)

This is an article in the Journal of Clinical Pharmacology's Core Entrustable Professional Activities in Clinical Pharmacology series that discusses drug-induced proarrhythmia and is offered as a teaching aid for medical students and residents. Drugs from diverse pharmacological classes can lead to multiple types of arrhythmias including the polymorphic ventricular tachycardia torsades de pointes (TdP). Although typically occurring in self-limiting bursts with or without associated symptoms, which can range from mild lightheadedness and palpitations to syncope and seizures, TdP can also occasionally progress to ventricular fibrillation and sudden cardiac death. To provide patients with the optimal therapeutic benefits of potentially proarrhythmic drugs, prescribers are responsible for obtaining a good understanding of the compound's benefit-risk properties and perform a judicious assessment of the patient's clinical characteristics and individual risk factors. Dose adjustments and/or additional monitoring of electrocardiograms and electrolyte balances may be appropriate in some cases. This article explains the pharmacological mechanism of action of drug-induced proarrhythmia associated with compounds that prolong the repolarization period, illustrates how this liability is conveyed in a drug's prescribing information (label), details the clinical characteristics of patients most susceptible to this type of proarrhythmia, and describes interventions that can be made if TdP occurs. Three clinical vignettes are provided at the end of the article to highlight the relevance of the preceding discussions., (© 2019, The American College of Clinical Pharmacology.)

One of the more challenging aspects of ECG interpretation is measurement and interpretation of the QT interval. This interval represents the time taken for the ventricles to completely repolarise after activation. Abnormal prolongation of the QT interval can lead to torsades de pointes, a form of potentially life-threatening polymorphic ventricular tachycardia (VT). Detection of a prolonged QT interval is essential as this can be a reversible problem, particularly in the context of the use of a variety of commonly prescribed medications in the hospital setting. Automated ECG printouts cannot be relied upon to diagnose QT interval prolongation; thus, the onus is on the clinician to identify it. This is a difficult task, as the normal QT interval is typically measured relative to the heart rate. Therefore, the QT interval often requires "correction" for the current heart rate, in order to correctly stratify the risk of torsades de pointes. A wealth of correctional formulae have been derived, but none has proven superior. We present an approach to the ECG in this context, and a step-by-step guide to manually measuring and correcting the QT interval, and an approach to management in common hospital-based clinical scenarios.

Stroke involving some areas of the cerebral hemisphere, such as insula, amygdala, and lateral hypothalamus, may cause changes in autonomic control of cardiac function. A 58-year-old woman presented to the emergency department for acute onset of left facial-brachial-crural hemiparesis and dysarthria. A brain CT scan showed subacute ischemic lesion with hemorrhagic infarction in right insular-rolandic cortex. Over the next few days ECG showed severe bradycardia with elongation of QTc, significative pauses (5 seconds), runs of nonsustained ventricular tachycardia and torsades de pointes. Drug induced and other several possible causes of elongation of QT and bradycardia such as hypokalemia, a history of heart failure, and structural heart disease were ruled out. The case confirms that insular cortex plays a major role in stroke-induced cardiovascular changes., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: The standard approach for urgent trans-venous temporary cardiac pacemaker (TVTP) implantation is fluoroscopy guidance. The delay in activation of the fluoroscopy-room and the transfer of unstable patients may be life-threatening. Echocardiography-guided TP implantation may increase the safety of the patients by obviating the need for in-hospital transfer. We examined the feasibility and safety of echocardiography-guided vs. fluoroscopy-guided TVTP implantation., Methods: From January 2015 to September 2017 data for consecutive patients who needed emergent TVTP implantation were retrospectively reviewed. Ultrasound-guided TVTP protocol that was introduced in our center in January 2015 involved ultrasound guidance for both central venous access and pacing lead positioning. Access sites included femoral, subclavian, or jugular veins. Electrodes were placed in the right ventricular apex by means of echocardiographic monitoring in intensive care unit or by fluoroscopic guidance. Endpoints were achievement of successful ventricular pacing and procedural complications., Results: Sixty-six patients (17 echocardiography-guided and 49 fluoroscopy-guided) were included. There were no differences in pacing threshold between the echocardiography-guided group and the fluoroscopy-guided group (0.75 ± 0.58 mA vs. 0.57 ± 0.35 mA, p = 0.24). The access site for implantation was femoral vein in 27% for the fluoroscopy-guided vs. none for the echocardiography-guided approach (p = 0.015). One hematoma and one related infection occurred in the fluoroscopy-guided group. The need for electrode repositioning was observed in 1 patient in each group. There were no procedural-related deaths in either group., Conclusions: Echocardiography-guided temporary cardiac pacing is a feasible and safe alternative to fluoroscopy-guided approach and significantly lowers the need for in-hospital transfer.

Today, understanding the true risk of adverse events in long-QT syndrome (LQTS) populations may be extremely complex and potentially dependent on many factors such as the affected gene, mutation location, degree of QTc prolongation, age, sex, and other yet unknown factors. In this context, risk stratification by genotype in LQTS patients has been extremely difficult, also during exercise practice, especially due to the lack of studies that would lead to a better understanding of the natural history of each mutation and its impact upon athletes. The creation of individualized guidelines for sport participation is a goal yet to be achieved not only due to the complexity of genotype effect on the phenotype in this patient population, but also due to penetrance in genotype-positive patients. This article summarizes current knowledge and raises questions concerning the difficult relationship between exercise practice and LQTS., (© 2018 Wiley Periodicals, Inc.)

In patients with ion channel disease the predominant arrhythmias are polymorphic ventricular tachycardias (VT), torsade de pointes tachycardia and ventricular fibrillation (VF). In only extremely rare cases is very rapid monomorphic ventricular tachycardia observed. This is why implantable cardioverter-defibrillators (ICDs) should always be programmed for treatment of VF only with high detection rates to avoid inappropriate discharges. In idiopathic VF and catecholaminergic polymorphic ventricular tachycardia (CPVT), no baseline electrocardiographic abnormalities can be detected, whereas in Brugada syndrome, long QT syndrome, early repolarisation syndrome and Anderson-Tawil syndrome alterations of the baseline ECG are very important to identify patients at risk.

An 18-year-old woman was found unresponsive by her mother. After the patient spontaneously regained consciousness, an electrocardiogram showed a markedly prolonged QT interval thought to be due to congenital long QT1. An implantable cardioverter defibrillator was placed. After being free of symptoms for 1 year, she spontaneously developed torsades de pointes that was successfully terminated by the defibrillator., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Context: The congenital long QT syndrome (LQTS) is an inherited channelopathy known for its electrocardiographic manifestations of QT prolongation and its hallmark arrhythmia, torsades de pointes (TdP). TdP can lead to syncope or sudden death and is often precipitated by triggers such as physical exertion or emotional stress. Given that athletes may be at particular risk for adverse outcomes, those suspected of having LQTS should be evaluated, risk stratified, treated, and receive appropriate counseling by providers with sufficient expertise according to the latest guidelines., Evidence Acquisition: The following keywords were used to query MEDLINE and PubMed through 2016: LQTS, LQT1, LQT2, LQT3, long QT, long QTc, prolonged QT, prolonged QTc, QT interval, QTc interval, channelopathy, channelopathies, athletes, torsades de pointes, and sudden cardiac death. Selected articles within this primary search, in addition to relevant references from those articles, were reviewed for relevant information and data. Articles with pertinent information regarding pathophysiology, evaluation, diagnosis, genetic testing, treatment, and guidelines for athletes were included, particularly those published in the prior 2 decades., Study Design: Clinical review., Level of Evidence: Level 3., Results: Diagnosis of LQTS involves eliciting the patient's family history, clinical history, and evaluation of electrocardiographic findings. Genetic testing for common mutations can confirm suspected cases. β-Blockers represent the mainstay of treatment, though interventions such as implantable cardioverter-defibrillator placement or left cardiac sympathetic denervation may be required. Properly evaluated and treated athletes with LQTS have a low risk of cardiac events., Conclusion: Detection and management of LQTS in the athletic population is crucial given the possibility of adverse outcomes with the stress of athletic participation. Preparticipation screening examinations should include a thorough clinical and family history. Screening electrocardiograms may display key findings consistent with LQTS while genetic testing can confirm the diagnosis. Formerly considered a strict contraindication to athletic participation, LQTS is now an increasingly manageable entity with proper evaluation and treatment by qualified and experienced providers., Competing Interests: The authors report no potential conflicts of interest in the development and publication of this article.

Ventricular tachycardias include ventricular tachycardia, ventricular fibrillation, and torsades de pointes; although these rhythms may be benign and asymptomatic, others may be life threatening and lead to increased morbidity and mortality. To optimize patient outcomes, ventricular tachycardias need to be rapidly diagnosed and managed, and often the electrocardiogram (ECG) is the first and only manifestation of a cardiac defect. Understanding of the initial electrocardiographic pattern and subsequent changes can lead to early intervention and an improved outcome. This article describes mechanisms, ECG characteristics, and management of ventricular tachycardias., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Drug-induced torsades de pointes (TdP) is a rare but potentially fatal adverse effect of commonly prescribed medications including cardiac and noncardiac drugs. Importantly, many drugs have been reported to cause the characteristic Brugada syndrome-linked electrocardiography (ECG) abnormalities and/or (fatal) ventricular tachyarrhythmias. Chlorpheniramine and propranolol have the arrhythmogenic effects reported previously. A review of literature revealed a large number of case reports of chlorpheniramine or propranolol use resulting in QTc prolongation, TdP, or both. However, we wish to report the case of a patient who was treated with a combination of chlorpheniramine and propranolol, whose ECG showed no QT prolongation but who suffered from cardiac arrest due to TdP.

Background: Cardiovascular disease and sudden cardiac arrest are the leading causes of death in the United States. Early defibrillation is key to successful resuscitation for patients who experience shockable rhythms during a cardiac arrest. It is therefore vital that the shock advisory of AEDs (automated external defibrillators) or defibrillators in AED mode be reliable and appropriate. The goal of this study was to better understand the performance of multiple lay-rescuer and hospital professional defibrillators in AED mode in their analysis of ventricular arrhythmias. The measurable objectives of this study sought to quantify: 1. No shock advisory for sinus rhythms at any rate. 2. Recognition and shock advisory for ventricular fibrillation (VF). 3. Recognition and shock advisory for monomorphic ventricular tachycardia (VT). 4. Recognition and shock advisory for Torsades de Pointes (TdP)., Methods: This is a prospective evaluation of two AEDs and four semi-automatic, hospital professional defibrillators. This study represents post-marketing evaluation of FDA approved devices. Each defibrillator was connected to multiple rhythm simulators and presented with simulated ECG waveforms 20 consecutive times at various rates when possible., Results: All four defibrillators and both AEDs tested consistently recognized normal sinus rhythm (NSR) from all rhythm sources, and did not recommend a shock for NSR at any rate (from 80 to 220 bpm). All four defibrillators and both AEDs recognized VF from all rhythm sources tested and recommended a shock 100% of the time. Variations were found in the shock advisory rates among defibrillators when testing simulated VT heart rates at or below 150 bpm. One AED tested did not consistently advise a shock for monomorphic VT or TdP at any tested rate., Conclusion: Lay-rescuer AEDs and professional hospital defibrillators tested in AED mode did not reliably recommend a shock for sustained monomorphic VT or TdP at certain rates, despite the fact that it is a critical component of the currently recommended treatment. These findings require further examination of the risk benefit analysis of shocking or not shocking rhythms such as TdP or pulseless VT., (Published by Elsevier Ireland Ltd.)

A 30-year-old woman, with no medical history, is operated on for breast implants. In recovery room, an episode of torsade de pointes occurs, progressing to ventricular fibrillation. The ECG after cardiopulmonary resuscitation and conversion to a normal sinus rhythm shows a corrected QT interval prolongation, whereas it is normalized after 48hours. We hypothesize that a ventricular fibrillation occurred after a torsade de pointes, due to drug-induced long QT syndrome during general anesthesia, with probably drug interaction., (Copyright © 2014 Société française d’anesthésie et de réanimation (Sfar). Published by Elsevier SAS. All rights reserved.)

Many drugs can significantly influence cardiac repolarisation causing an increased duration of this repolarisation phase, challenging the repolarisation reserve. This may set the stage for life-threatening ventricular arrhythmias such as torsades de pointes (TdP). TdP generally occurs in conjunction with a prolonged QT interval (QT) on the electrocardiogram. The Dutch Poisons Information Centre (NVIC) often receives information requests about drugs that can influence the QT already at therapeutic dosages. Drug-induced QT prolongation is dose dependent and hence can be particularly pronounced in overdose situations. Also, additional risk factors for the development of life-threatening arrhythmias are often present in intoxicated patients. This review focuses on identification and management of drug-intoxicated patients who are at risk for a reduction in their repolarisation reserve, measured by their QT interval. The QT interval is strongly dependent on heart rate, which has led to the introduction of different methods to adjust the QT interval, i.e. the QTc. Bazett's formula, which has been used for decades, lacks accuracy concerning QTc calculation at higher and lower heart rates, situations often relevant when dealing with intoxicated patients. Additionally, we highlight drugs with QT-prolonging potential that are commonly associated with an overdose setting in the Netherlands. Finally, standard treatment options specifically pointed toward the intoxicated patient at risk of QT prolongation and TdP will be discussed.

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. We stress that these premature beats are often misclassified as supraventricular since the two major factors (slow initial depolarisation of the working myocardium and structural abnormalities of the left ventricle) responsible for typical morphological features of ventricular beats are lacking.

In this article, we explore the clinical and cellular phenomena of primary electrical diseases of the heart, that is, conditions purely related to ion channel dysfunction and not structural heart disease or reversible acquired causes. This growing classification of conditions, once considered together as "idiopathic ventricular fibrillation," continues to evolve and segregate into diseases that are phenotypically, molecularly, and genetically unique., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Long QT syndrome in the infant with 2:1 atrioventricular block is a malignant form of disease associated with frequent torsade de pointes in some cases. Those patients that do not respond to antiarrhythmic therapy are particularly challenging to manage. Ventricular pacing in this patient population has been shown to reduce arrhythmic events. We report a case of a newborn with frequent torsade de pointes requiring defibrillation and cardiopulmonary resuscitation with immediate shortening of the QTc interval with ventricular pacing and subsequent resolution of torsade de pointes., (© 2012 Wiley Periodicals, Inc.)

A 38-year-old obese woman presented with recurrent polymorphic ventricular tachycardia secondary to persistent hypokalemia necessitating more than 40 DC shocks. All endocrine investigations for hypokalemia were negative with impression of "mysterious hypokalemia." On repeated inquiry, a hidden history of licorice use was elicited causing persistent hypokalemia. The case highlights a life threatening complication of licorice use. In addition, it reiterates the importance of repeated history taking in a patient with undiagnosed hypokalemia and torsade de pointes which avoided a device therapy., (©2013 Wiley Periodicals, Inc.)

A 75-year-old man presented to the emergency department (ED) for syncope and was found to have intermittent runs of torsades de pointes (TdP). The patient had a medical history significant for disseminated coccidiomycosis and was on prophylactic fluconazole. Forty-eight hours prior to presentation, the patient had intractable nausea and vomiting and was unable to take anything orally. He eventually presented to the ED with severe hypokalaemia and hypomagnesaemia with repeat symptomatic runs of TdP, which required overdrive transvenous pacing. During the patient''s admission, his electrolytes were aggressively replete. Fluconazole was discontinued, and prior to discharge, the patient recovered fully with ECGs showing a normalisation of the QT interval.

History: A 17-year-old female student presented in our emergency room after a seizure with motoric fits and enuresis. It was the second event of this kind within 3 weeks., Investigations: The resting ECG on admission showed sinus bradycardia at 45 bpm and a remarkable repolarisation with notched or bifurcated T waves in several leads. Further clinical investigations were unremarkable., Treatment and Course: As an arrhythmogenic syncope (bradycardia or tachycardia related) was presumed, beta-blocker therapy was initiated and an implantable loop recorder (ILR) was inserted. Approximately one year after the index event, the student was brought to the emergency room by ambulance after another seizure. Interrogation of the ILR revealed torsade de pointes tachycardia with spontaneous termination after 1 min and 24 s. A dual-chamber ICD for secondary prophylaxis of sudden cardiac death was therefore implanted and the dose of beta-blocker was increased. Genetic analysis for long-QT-syndrome (LQTS) was negative with regards to the most frequent known gene loci. For 6 months the patient has been free of symptoms., Conclusion: Arrhythmogenic syncopes can clinically resemble epileptic seizures ("convulsive syncope"). During basic work-up of syncope, the 12 lead ECG may provide valuable clues indicating an arrhythmogenic cause of syncope, showing excitation as well as repolarisation abnormalities. If an arrhythmogenic cause of syncope is suspected but ECG documentation as a proof of diagnosis is missing, implantation of an ILR can be useful. In LQTS, multiple gene mutations are known but cover only a fraction of clinical LQTS., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: Torsade de pointes is a rare but potentially fatal arrhythmia. More than 40 cases of perioperative torsade de pointes have been reported in the literature; however, the current evidence regarding this complication is very limited. To improve our understanding, we performed a systematic review and meta-analysis of all published case reports of perioperative torsade de pointes., Methods: MEDLINE was systematically searched for cases of perioperative torsade de pointes. We included patients of all age groups and cases that occurred from the immediate preoperative period to the third postoperative day. Patient and case characteristics as well as QT interval data were extracted., Results: Forty-six cases of perioperative torsade de pointes were identified; 29 occurred in women (67%), and 2 episodes were fatal (case fatality rate: 4%). Craniotomies and cardiac surgery accounted for 40% of all cases. Preceding events identified by the authors were hypokalemia (12/46, 26%; 99% confidence interval [CI], 9%-43%) and bradycardia (7/46, 15%; 99% CI, 2%-28%). Drugs were implicated in approximately one third of the events (14/46, 30%; 99% CI, 13%-48%). The mean corrected QT (QTc) at baseline was 457 ± 67 milliseconds (minimum 320 milliseconds; maximum 647 milliseconds; data available in 27/46 patients). At the time of the event, the mean QTc increased to 575 ± 77 milliseconds (minimum 413 milliseconds; maximum 766 milliseconds; data available in 33/46 patients). On average, QTc increased by +118 milliseconds (99% CI, 70-166 milliseconds; P < 0.001) between baseline and after the torsade de pointes event. All patients, except for 2, had a substantial prolongation of their QTc interval at the time of the event., Conclusions: This systematic review identified several common risk factors for perioperative torsade de pointes. Given the nearly uniform presence of a substantial QTc interval prolongation at the time of a torsade de pointes episode, increased vigilance for perioperative QTc interval prolongation may be warranted.

Objective: A regulatory science priority at the Food and Drug Administration (FDA) is to promote the development of new innovative tools such as reliable and validated computational (in silico) models. This FDA Critical Path Initiative project involved the development of predictive clinical computational models for decision-support in CDER evaluations of QT/QTc interval prolongation and proarrhythmic potential for non-antiarrhythmic drugs., Methods: Several classification models were built using predictive technologies of quantitative structure-activity relationship analysis using clinical in-house and public data on induction of QT prolongation and torsade de pointes (TdP) in humans. Specific models were geared toward prediction of high-risk drugs with attention to outcomes from thorough QT studies and TdP risk based on clinical in-house data. Models used were independent of non-clinical data or known molecular mechanisms. The positive predictive performance of the in silico models was validated using cross-validation and independent external validation test sets., Results: Optimal performance was observed with high sensitivity (87%) and high specificity (88%) for predicting QT interval prolongation using in-house data, and 77% sensitivity in predicting drugs withdrawn from the market. Furthermore, the article describes alerting substructural features based on drugs tested in the clinical trials., Conclusions: The in silico models provide evidence of a structure-based explanation for these cardiac safety endpoints. The models will be made publically available and are under continual prospective external validation testing and updating at CDER using TQT study outcomes.

Torsades de pointes ("twisting of points") (TdP) is a broad complex tachyarrhythmia which was first described in 1966 by Francois Dessertenne and usually results from prolongation of the QT interval.(1) A wide variety of drugs have been shown to prolong the QT interval in susceptible individuals.(2) We present the case of a former intravenous heroin user presenting with several episodes of TdP which were caused by QT prolongation due to methadone treatment and exacerbated by hepatitis B/C infection. Despite aggressive medical treatment and withdrawal of methadone, he had recurrent episodes of TdP which required continuous temporary cardiac pacing for six days. He was found to have moderate LV dysfunction on his echocardiogram and unobstructed coronary arteries on coronary angiography. He underwent implantation of a defibrillator due to concerns about further episodes of ventricular arrhythmias which could recur even in the absence of further methadone use., (Copyright © 2013 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.)

Longed QT syndromes are cardiac repolarization disorders characterized by longed QT intervals on ECG. This electrophysiological abnormality may lead to syncope or sudden cardiac death due to rapid, polymorphic ventricular tachycardia (VT). Licorice root (Glycyrrhizin glabra root) contains Glycyrrhizin, sterols and many flavones. Glycyrrhizin may have effects on cardiac repolarization and depolarization through the autonomic nervous system. We present a case of polymorphic VT (torsades de pointes) secondary to drinking 5-6 glasses of licorice root tea for constipation for 2 days prior to admission to emergency department. Licorice root consumption should be taken into account in all patients admitted to the hospital for cardiac arrhythmia. It may cause cardiac arrhythmia when consumed regularly and in excessive amounts.

This report describes a case of a patient with long QT syndrome (LQTS) with recurrent episodes of torsades de pointes (TdP). Use of biventricular pacing (BiVP) resulted in a shorter QT interval and a shorter T-peak-end interval and prevented further episodes of TdP. These findings suggest that BiVP may be helpful in patients with LQTS and refractory TdP., (©2011, The Authors. Journal compilation ©2011 Wiley Periodicals, Inc.)