1/8. Focal ablation of chaotic atrial rhythm in an infant with cardiomyopathy.Chaotic atrial rhythm in infants has been defined similar to multifocal atrial tachycardia in adults, implying a multifocal etiology. However, its ECG appearance resembles atrial fibrillation, which sometimes has a unifocal ectopic mechanism amenable to catheter ablation. Curative focal radiofrequency ablation was performed in a 4-month-old infant with chaotic atrial rhythm and dilated cardiomyopathy. Left ventricular function subsequently returned to normal. Reversibility of associated cardiomyopathy supports aggressive rhythm management of chaotic atrial rhythm. In this patient, the unifocal origin allows insight into the pathophysiology of the rhythm and demonstrates the potential utility of catheter ablation for refractory cases.- - - - - - - - - - ranking = 1keywords = atrial fibrillation, fibrillation (Clic here for more details about this article) |
2/8. Cardiac leiomyosarcoma of the right atrium in a teenager: unusual manifestation with a lifetime history of atrial ectopic tachycardia.A 16-year-old girl presented with atrial fibrillation. Transesophageal echocardiography revealed a right atrial leiomyosarcoma. Her past medical history was remarkable for incessant atrial ectopic tachycardia (AET) beginning in early infancy and continuing throughout childhood and adolescence that was refractive to medical and nonpharmacological treatment. After combined surgical and medical therapy, normal sinus rhythm was restored and the patient is currently in complete remission with no recurrent symptoms or atrial arrhythmias at 31 months after surgery and 23 months after the discontinuation of chemotherapy. Atrial tachycardia may be the first, and for prolonged periods, the only manifestation of a cardiac tumor and should prompt thorough investigation of its underlying morphological substrate.- - - - - - - - - - ranking = 1keywords = atrial fibrillation, fibrillation (Clic here for more details about this article) |
3/8. Iterative atrial tachycardia originating from the coronary sinus musculature.A case of iterative atrial tachycardia leading to dilated cardiomyopathy is reported. During electrophysiologic study, the tachycardia showed a markedly irregular cycle length associated with changes in atrial activation breakthrough as demonstrated by coronary sinus (CS) recordings and frequently degenerated into self-terminating atrial fibrillation. Left atrial transseptal mapping demonstrated the earliest endocardial atrial activation close to the posterolateral mitral annulus, but this was invariably later than that recorded within the CS, where low-energy radiofrequency applications eliminated the tachycardia. No acute vessel damage was observed at postablation CS angiography. In accordance with previously published experimental data, we hypothesized that the muscular sleeves surrounding the CS might be involved in the genesis of this tachycardia. During 6-month follow-up, the patient remained asymptomatic without tachycardia recurrences and with complete recovery of left ventricular function, confirming the reversible nature of the tachycardia-induced cardiomyopathy.- - - - - - - - - - ranking = 1keywords = atrial fibrillation, fibrillation (Clic here for more details about this article) |
4/8. A novel approach to the management of symptomatic junctional and ectopic atrial rhythms.Chronic recurrent junctional and ectopic atrial rhythms are a challenge to manage as they are not responsive to pharmacologic therapy and will usually inhibit standard pacemakers. This report presents two patients with junctional and low atrial rhythms who were successfully managed with a recently introduced atrial overdrive suppression algorithm intended for the treatment of paroxysmal atrial fibrillation. In contrast with the standard AAI mode, the AF suppression algorithm paces progressively faster in response to sensed atrial events (or junctional rhythms with retrograde conduction). Maintaining atrial pacing produces a more normal A-V interval with relieve of symptoms.- - - - - - - - - - ranking = 1keywords = atrial fibrillation, fibrillation (Clic here for more details about this article) |
5/8. Treatment of sustained left atrial tachycardia by ostial pulmonary vein isolation.This report describes two patients with sustained regular left atrial tachycardias originating from multiple pulmonary veins in the absence of clinical evidence of atrial fibrillation. The tachycardias were eliminated by activation map-guided pulmonary vein isolation. Stable sustained regular pulmonary vein tachycardias unassociated with atrial fibrillation are uncommon, and they belong to the spectrum of pulmonary vein arrhythmias that include the more common paroxysmal and unstable tachycardias engendering atrial fibrillation.- - - - - - - - - - ranking = 3keywords = atrial fibrillation, fibrillation (Clic here for more details about this article) |
6/8. Incessant ectopic atrial tachycardia and sudden death.A patient with refractory and incessant ectopic atrial tachycardia (IEAT) is reported in whom it was possible to document, during ECG (Holter) the occurrence of aborted sudden death by spontaneous ventricular fibrillation (VF). Following the second of two attempts at surgical ablation of the origin of the IEAT, the patient has been asymptomatic without antiarrhythmic drugs and in sustained sinus rhythm for 24 months. Although we cannot exclude the residual action of amiodarone and flecainide (proarrhythmia) or the residual peripartum cardiomyopathy it is probable that the observed VF was a true complication of a cardiomyopathy induced by a chronically increased heart rate (HR). Although unclear, this VF might be considered as a form of adrenergic-dependent long qt syndrome due to early afterdepolarization in the presence of predisposing myocardial conditions.- - - - - - - - - - ranking = 0.46731780911129keywords = fibrillation (Clic here for more details about this article) |
7/8. adenosine in wide complex tachycardia: potential pitfalls in diagnostic value.adenosine is an efficacious diagnostic and therapeutic agent in the acute management of wide complex tachycardias. Its potent negative dromotropic effect terminates supraventricular tachycardias involving the atrioventricular node, allowing differentiation from tachycardias of atrial and ventricular origin. Its extranodal actions, however, may lead to potential pitfalls in arrhythmia diagnosis. We report three unusual cases of patients with adenosine-sensitive tachycardias. One patient had idiopathic ventricular tachycardia originating from the right ventricular outflow tract, one had ectopic atrial tachycardia, and one had atrial fibrillation with rate-related intraventricular aberration. Recognition of the extranodal actions of adenosine and careful ECG evaluation before and after adenosine administration should maximize the diagnostic accuracy of adenosine in wide complex tachycardias.- - - - - - - - - - ranking = 1keywords = atrial fibrillation, fibrillation (Clic here for more details about this article) |
8/8. Proarrhythmic effects of class Ic drugs.Three cases managed with class Ic antiarrhythmic drugs but with subsequent aggravation of arrhythmias are reported herein. A 58-year-old man given 300 mg of flecainide for atrial flutter developed sinus arrest and transient ventricular fibrillation. A 42-year-old man with a postoperative condition of tetralogy of fallot who received 300-mg doses of flecainide for sustained ventricular tachycardia had spontaneous sustained ventricular tachycardia. A 74-year-old man given 150 mg of propafenone for atrial tachycardia developed sustained ventricular tachycardia. The present cases illustrate that class Ic drugs may exacerbate ventricular arrhythmias, and their use may reveal concealed sinus node dysfunction. This may be due to marked slowing of conduction and prolonged ventricular refractoriness, which are characteristic of the class Ic drugs; also, it is probable that the patients' underlying cardiac conditions served as contributing factors.- - - - - - - - - - ranking = 0.46731780911129keywords = fibrillation (Clic here for more details about this article) |