In the long QT syndromes (LQTS), malfunction of ion channels impairs ventricular repolarisation and triggers a characteristic ventricular tachyarrhythmia: torsade de pointes. Symptoms in the LQTS (syncope or cardiac arrest) are caused by this arrhythmia. In congenital LQTS, mutations in the genes encoding for ion channels cause this channel malfunction. Six genotypes (LQT1 to LQT6) have been identified, and attempts are being made to correlate different mutations with clinical signs and specific therapy. In acquired LQTS, channel malfunction is caused by metabolic abnormalities or drugs. The list of drugs that may impair ion-channel function expands continuously. Moreover, attributes that increase the risk for drug-induced torsade (eg, female sex, recent heart-rate slowing, or hypokalaemia) and electrocardiographic "warning signs" are recognised. Recent data suggest that patients with an acquired LQTS have some underlying predisposition to proarrhythmia. Mutations causing "silent" forms of congenital LQTS, in which the patient remains free of arrhythmias until exposed to drugs that further impair repolarisation, are now recognised.
Sudden, unexpected death in avid dieters using the liquid-protein-modified-fast diet. Observations in 17 patients and the role of the prolonged QT interval
Cardiac arrhythmias in acute central nervous system disease. Successful management with stellate ganglion block
Bradycardia-induced abnormal QT prolongation in patients with complete atrioventricular block with torsades de pointes
Left cardiac sympathetic denervation in the therapy of congenital long QT syndrome. A worldwide report
Magnesium suppression of early afterdepolarizations and ventricular tachyarrhythmias induced by cesium in dogs
Clinical characteristics of patients with ventricular fibrillation during antiarrhythmic drug therapy
Subarachnoid hemorrhage: frequency and severity of cardiac arrhythmias. A survey of 70 cases studied in the acute phase
Torsade de pointes: the long-short initiating sequence and other clinical features: observations in 32 patients
Spontaneous sequences of onset of torsade de pointes in patients with acquired prolonged repolarization: quantitative analysis of Holter recordings
Block of IKs, the slow component of the delayed rectifier K+ current, by the diuretic agent indapamide in guinea pig myocytes
Long QT syndrome patients with mutations of the SCN5A and HERG genes have differential responses to Na+ channel blockade and to increases in heart rate. Implications for gene-specific therapy
Extracellular potassium modulation of drug block of IKr. Implications for torsade de pointes and reverse use-dependence
Management of patients with atrial fibrillation. A Statement for Healthcare Professionals. From the Subcommittee on Electrocardiography and Electrophysiology, American Heart Association
Genetically defined therapy of inherited long-QT syndrome. Correction of abnormal repolarization by potassium
Multiple mechanisms in the long-QT syndrome. Current knowledge, gaps, and future directions. The SADS Foundation Task Force on LQTS
Torsade de pointes with an antihistamine metabolite: potassium channel blockade with desmethylastemizole
Cellular and ionic mechanisms underlying erythromycin-induced long QT intervals and torsade de pointes
Sodium channel block with mexiletine is effective in reducing dispersion of repolarization and preventing torsade des pointes in LQT2 and LQT3 models of the long-QT syndrome
Mutation of the gene for IsK associated with both Jervell and Lange-Nielsen and Romano-Ward forms of Long-QT syndrome
Block of the rapid component of the delayed rectifier potassium current by the prokinetic agent cisapride underlies drug-related lengthening of the QT interval
Improvement of repolarization abnormalities by a K+ channel opener in the LQT1 form of congenital long-QT syndrome
Prevention of torsade de pointes in the congenital long QT syndrome: use of a pause prevention pacing algorithm
Polymorphic ventricular tachyarrhythmias in the absence of organic heart disease: classification, differential diagnosis, and implications for therapy
Influence of genotype on the clinical course of the long-QT syndrome. International Long-QT Syndrome Registry Research Group
Selectivity of atipamezole, yohimbine and tolazoline for alpha-2 adrenergic receptor subtypes: implications for clinical reversal of alpha-2 adrenergic receptor mediated sedation in sheep
Severe bacterial infection: increased mortality in elderly women with low body weight taking drugs prolonging the QTc interval
Activation of cardiac human ether-a-go-go related gene potassium currents is regulated by alpha(1A)-adrenoceptors
Multiple mechanisms of hERG liability: K+ current inhibition, disruption of protein trafficking, and apoptosis induced by amoxapine
Effects of dose ranging of adenosine infusion on electrocardiographic findings during and after general anesthesia
Inaccurate electrocardiographic interpretation of long QT: the majority of physicians cannot recognize a long QT when they see one
Electrical storm as initial presentation of arrhytmogenic right ventricular cardiomyopathy in an elderly woman
HERG binding specificity and binding site structure: evidence from a fragment-based evolutionary computing SAR study
Teratogenicity by the hERG potassium channel blocking drug almokalant: use of hypoxia marker gives evidence for a hypoxia-related mechanism mediated via embryonic arrhythmia
Additive effects of ziprasidone and D,L-sotalol on the action potential in rabbit Purkinje fibres and on the hERG potassium current
Prevention of clofilium-induced torsade de pointes by prostaglandin E2 does not involve ATP-dependent K+ channels
Abnormalities of rate-corrected QT intervals in Parkinson's disease-a comparison with multiple system atrophy and progressive supranuclear palsy
Measurement of potassium concentration in salivary and sweat fluids as a screening test for the long QT1 syndrome
Management of ventricular fibrillation or unstable ventricular tachycardia in patients with congenital long-QT syndrome: a suggested modification to ACLS guidelines
Death in bathtub revisited with molecular genetics: a victim with suicidal traits and a LQTS gene mutation
Pause-dependent torsade de pointes following acute myocardial infarction: a variant of the acquired long QT syndrome
The assessment of potential for QT interval prolongation with new pharmaceuticals: impact on drug development
Beyond size, ionization state, and lipophilicity: influence of molecular topology on absorption, distribution, metabolism, excretion, and toxicity for druglike compounds
State-dependent blockade of human ether-a-go-go-related gene (hERG) K(+) channels by changrolin in stably transfected HEK293 cells
Proarrhythmic potential of halofantrine, terfenadine and clofilium in a modified in vivo model of torsade de pointes
Inhibition of the current of heterologously expressed HERG potassium channels by flecainide and comparison with quinidine, propafenone and lignocaine
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