ABSTRACT
Background: Since February 2002, Flextend® electrode catheters are used at the Cardiovascular Unit of the Catholic University Clinical Hospital. These transvenous catheters have an IS-1 connector, silicone coating, active fixation and retractile helix with dexamethasone acetate. Aim: To report early and one year results using Flextend® catheters. Material and methods: Retrospective analysis of all patients that received an implant of a Flextend® catheter in the Unit. Results: Forty one Flextend® catheters were implanted in 24 patients, without acute displacement or clinical pericarditis. In 18 electrode catheters located in the right atrium the mean values for p wave, stimulation threshold and impedance at the moment of placement, were 2.9±1.4 mV, 0.8±0.4 V and 522±86 Ohms, respectively. The figures 24 hours after placement were 3.6±2.1 mV, 0.8±0.3 V and 612±69 Ohms, respectively. In 23 electrode catheters in the right ventricle, mean values at the moment of placement for R wave, stimulation threshold and impedance were 11.3±3.6 mV, 0.8±0.2 V and 756±108 Ohms, respectively. The figures 24 hours after placement were 3.6±2.1 mV, 0.8±0.3 V and 612±69 Ohms, respectively. In one patient, the stimulation threshold increased two months after placement and required a new intervention. Conclusions: Flextend® catheters ca be placed successfully with a low rate of complications and stable function parameters on follow up.
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Electric Stimulation , Electrodes, Implanted/standards , Pacemaker, Artificial , Technology Assessment, Biomedical , Arrhythmias, Cardiac/therapy , Cardiography, Impedance , Follow-Up Studies , Heart Conduction System , Retrospective Studies , Sensory ThresholdsABSTRACT
La taquicardia ventricular del tracto de salida de ventrículo derecho (TVD) es causa del 70 por ciento de las taquicardias ventriculares idiopáticas. Entre octubre de 1995 y agosto de 1997, siete pacientes (4 hombres), con edad promedio de 35 años (6-60), fueron sometidos a estudio electrofisiológico (EEF) y fulguración con radiofrecuencia (FRF) por TVD. El tiempo promedio de evolución de los síntomas fue de 21 meses. Los 7 pacientes tenían palpitaciones y 2 síncope. Ninguno tenía cardiopatía estructural de base y todos habían fracasado el tratamiento farmacológico. Durante el EEF, en tres pacientes la TV se inició espontáneamente, en cuatro con estimulación ventricular e isoproterenol y en uno con estimulación auricular. Para la FRF se avanzó un catéter vía vena femoral derecha, y bajo visión radioscópica, se mapeó el tracto de salida del ventrículo derecho con técnica de pace mapping. La FRF tuvo éxito en los 7 pacientes. Hubo una recidiva a los 92 días, con refulguración exitosa. El promedio de aplicaciones de radiofrecuencia fue de 10 (rango de 1 a 19). El tiempo promedio de laboratorio fue de 4,6 ñ 0,6 horas, con un tiempo de radioscopia de 27 ñ 5 min. No hubo complicaciones ni recidivas de las TVDs. Conclusión: la FRF es una alternativa terapéutica eficaz y segura para pacientes con TVD
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Catheter Ablation/methods , Arrhythmogenic Right Ventricular Dysplasia/surgery , Electrocoagulation/methods , Amiodarone/therapeutic use , Arrhythmogenic Right Ventricular Dysplasia/complications , Electrocardiography/methods , Tachycardia, Ventricular/drug therapy , Tachycardia, Ventricular/etiologyABSTRACT
We report a 41 years old female, previously operated of an atrial septal defect, presenting with a persisting atrial flutter. Sinus node dysfunction became evident during an electrophysiological study at the moment of interrupting the flutter with electrical stimulation. The patient was treated with his bundle ablation and implantation of a definitive pacemaker. After one year of follow up, she is devoid of symptoms
Subject(s)
Humans , Female , Adult , Atrial Flutter/diagnosis , Sick Sinus Syndrome/physiopathology , Atrial Flutter/surgery , Atrial Flutter/etiology , Atrial Flutter/drug therapy , Sick Sinus Syndrome/complications , Sick Sinus Syndrome/diagnosis , Digoxin/therapeutic use , Amiodarone/therapeutic use , Catheter Ablation , Electrocardiography, Ambulatory , Clinical EvolutionABSTRACT
Radiofrecuency fulguration is the definitive treatment of several supraventricular and ventricular arrythmias. During radiofrecuency application, the conduction in a specific zone is interrupted as a consequence of cellular necrosis and edema. The disappearance of edema, minutes or hours after the procedure, allows the reappearance of conduction and arrythmias. On the other hand, the definitive lesion is larger than the one caused acutely, due to the progression of the scar. We report four patients, in whom there was an apparent failure of the fulguration, since at the end of the procedure there was conduction in the fulgurated zone, the tachycardia was inducible or pre excitation and arrythmias reappeared during the follow up. All four were subjected to a new eletrophysiological study and in all, fulguration had been effective. We conclude that these late effects of fulguration are due to the slow progression of fibrosis, that continues days or weeks after the procedure
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Arrhythmias, Cardiac/surgery , Catheter Ablation/adverse effects , Electrocoagulation/adverse effects , Recurrence , Heart Block , Electroencephalography/methodsABSTRACT
Ventricular tachycardia due to reentry within the bundle branches occurs in the presence of left ventricular dilatation and conduction alterations in the His-Purkinje system. A macro-reentry is formed by the His bundle, left and right bundles and ventricular myocardium. The anatomical substrate of this arrhythmia is ventricular dilatation. However, it may appear in healthy hearts. Alterations of intraventricular conduction are reflected by a prolongation of PR intenval and bundle branch block in the surface EKG and prolongation of HV interval in the endocavitary registry. During tachycardia, His activation precedes ventricular activation. We report three patients aged 55,58 and 78 years old with a dilated cardiomyopathy and ventricular tachycardia due to reentry within the bundle branches. All had a left bundle branch block and a prolonged HV internal. The arrhythmia was induced during the study in two patients. All were subjected to radiofrequency fulguration of the right branch of the His bundle. After fulguration, two remained with a pattern of complete right bundle branch block and one with a complete intermittent AV block. All three are free of arrhythmic events
Subject(s)
Humans , Male , Middle Aged , Tachycardia, Atrioventricular Nodal Reentry/diagnosis , Tachycardia, Ventricular/diagnosis , Tachycardia, Ventricular/therapy , Catheter Ablation , Electrocardiography/methods , ElectrocoagulationABSTRACT
Background: Accessory pathways are muscular connections between auricles and ventricles, present in different points of mitral and tricuspid annuluses. These pathways participate in 50 percent of Paroxysmal supraventricular tachycardias and the definitive cure of the arrhythmia is their ablation. Aim: To report our experience in patients with right accessory pathways. Patients and methods: 50 consecutive patients treated between 1990 and 1996 are reported. Eight had a history of syncope, two had a diagnosis of Epstein disease and 36 had a pre-excitation in the surface electrocardiogram. Results: Fifty four accessory pathways were identified, since four patients had two pathways. Twenty four pathways were posteroseptal, 15 were lateral, 9 were medioseptal and 6 were anteroseptal. One patient had also a nodal reentry tachycardia. Fulguration was attempted in 39 patients and it was finally successful in 32. Three patients required more than one session. There were six relapses and all were successfully ablated in a second session. A mean of 28 radiofrequency applications were done (range 1- 76), mean laboratory time was 6 hours and mean radioscopy time was 70 min. Four patients had a transient atrioventricular conductor blockade. Conclusions: Radiofrequency ablation of accessory pathways has a high degree of success and a low rate of complications
Subject(s)
Humans , Male , Female , Child, Preschool , Adolescent , Adult , Middle Aged , Arrhythmia, Sinus/surgery , Catheter Ablation/methods , Electrocoagulation/methods , Atrial Flutter/physiopathology , Tachycardia, Supraventricular/surgery , Atrial Fibrillation/physiopathology , Tachycardia, Paroxysmal/surgeryABSTRACT
Siendo la fulguración una técnica médica, enfermería tiene una activa participación en el desarrollo de ésta. En este trabajo sólo se definió la atención directa que se le brinda al paciente durante el procedimiento aplicando el proceso de atención de enfermería y no se mostró la participación activa que tiene la enfermera en el desarrollo de este procedimiento, ya que nos parece importante definir la atención directa con el paciente a fin de no confundir roles y acciones
Subject(s)
Child , Catheter Ablation , Nurses , Patient Care , Pediatrics , Role , Tachycardia, Paroxysmal , Tachycardia, Supraventricular , Arrhythmias, Cardiac , ChildABSTRACT
La taquicardia ventricular por reentrada de rama a rama corresponde a un tipo de taquicardia ventricular monomorfa sostenida que se presenta en pacientes con miocardiopatía dilatada y transtornos de conducción del sistema His-Purkinje. Esta taquicardia produce compromiso hemodinámico y hasta un 75 por ciento de los pacientes debuta con síncope o muerte súbita. Con el desarrollo de la electrofisiología se ha comprendido su mecanismo, y la fulguración con radiofrecuencia permite un tratamiento definitivo mediante interrupción de la conducción por la rama derecha. Presentamos el caso clínico de un paciente con miocardiopatía dilatada de origen valvular, quien presentó taquicardia por reentrada de rama a rama y fue sometido a fulguración con radiofrecuencia
Subject(s)
Humans , Male , Middle Aged , Electrocoagulation/methods , Tachycardia, Ventricular/therapy , Cardiomyopathy, Dilated/complications , Cardiomyopathy, Dilated/drug therapy , Diagnosis, Differential , Tachycardia, Ventricular/diagnosis , Tachycardia, Ventricular/etiology , Verapamil/therapeutic useABSTRACT
Nodal reentrant supraventricular paroxysmal tachycardia corresponds to a reentry circuit established between fibers with different conduction relocities and refractory periods in the atrioventricular mode. These are the slow and fast nodal pathways. That ventricular tissue does not form part of the circuit of this arrbythmia is accepted nowadays, and the involvement of atrial tissue is discussed. We report a 57 years old male with a nodal reentrant tachycardia. In the electrophystological study be presented an atrial and ventricular dissociation during the tachycardia. These findings allow a better undestanding of the electrophysiological substrae of this arrhytmia
Subject(s)
Humans , Male , Middle Aged , Tachycardia, Supraventricular/diagnosis , Tachycardia, Paroxysmal/diagnosis , Tachycardia, Sinoatrial Nodal Reentry/diagnosis , Tachycardia, Sinoatrial Nodal Reentry/therapy , Electrocardiography/methods , Electrocoagulation/methods , Electrophysiology/methodsABSTRACT
Patients and methods: We report six patients (five male), aged 35 years old as a mean, with idiopathic left ventricular tachycardia that were subject to conventional electrophysiological studies with atrial and ventricular simulation programs and radiofrequency fulguration, between December 1993 and May 1996. Results: The mean lapse of disease was 24 months and five patients received antiarrytmic medications previously. All tachycardias had a morphology with an image of right bundle branch block. Radiofrequency fulguration was done after obtaining a satisfactory pace mapping of at least 11 of the 12 superficial EKG derivations. The procedure was successful in five patients and two had a relapse. One of the relapsed patients was successfully fulgurated again. Conclusions: Radiofrequency fulguration for idiopathic ventricular tachycardias is a safe and effective therapeutic procedure
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Tachycardia, Ventricular/physiopathology , Tachycardia, Ventricular/surgery , Catheter Ablation/methods , Electrophysiology/methodsABSTRACT
Patients and methods: Nine patients with dilated cardiomyopathy were studied. Hemodynamic and tissular perfusion values, echocardiographic and radioisotopic ventricular function parameters were measured before and after six hours of AV interval shortening with electrical stimulation of the heart. Results: After electrical stimulation, cardiac output increased from 3.38 ñ 0.8 to 32.87 ñ 0.79 l/min (p < 0.05). Pulmonary capillary pressure decreased from 23.8 ñ 8.9 to 19.8 ñ 9.2 mm Hg (p = NS). There were no significant changes in ventricular function parameters or in systemic and pulmonary pressures. Conclusions: Electrical shortening of AV interval in patients with dilated cardiomyopathy increases cardiac output but does not change ventricular function parameters
Subject(s)
Humans , Male , Adult , Middle Aged , Cardiomyopathy, Dilated/physiopathology , Hemodynamics/physiology , Creatine/urine , Creatine/blood , Lactic Acid/blood , Cardiac Pacing, Artificial/methods , Electric Stimulation/methods , Ventricular Function/physiology , Cardiac Output/physiology , Blood Pressure/physiology , Systole/physiologyABSTRACT
Nine patients (8 males) whose ages ranged from 6 to 72 years old were studied. Two patients had an operated congenital cardiopathy, 2 had high blood pressure, 1 has no subject previously to radiofrequency ablation due to a left paraspecific pathway; 1 developed a cardiac failure secondary to tachycardia and 3 relapses in the first month after the procedure, of these, 2 patients were succesfully treated again. After a mean follow up of 4.5 months, these patients are asymptomatic and without antiarrythmic drugs. Analyzis of obtained signals, showed that radiofrequency that interrupted atrial flutter always occurred in zones of double potentials. Radiofrequency ablation is an effective tretament for atrial flutter and the zone of succesful ablation is associated to the presence of double atrial potentials
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Atrial Flutter/surgery , Catheter Ablation/methods , Arrhythmias, Cardiac/surgery , Arrhythmias, Cardiac/physiopathology , Atrial Flutter/physiopathology , Electrophysiology/methodsABSTRACT
Supraventricular tachycardias (SVT) are the most frequent cause of tachycardia in children. Its pharmacological treatment has adverse effects, is not curative and is not always effective. During the last few years radiofrequency ablation (RF-A) has changed the treatment. The purpose of this study is to evaluate our experience in RF-A in children with SVT. Between 1990 and 1995, 92 patients (1 mont to 17 years old) underwent electrophysiological study after the diagnosis of SVT. RF-A was attempted in 55 patients with accessory pathways (AP), slow-pathway of the atrioventricular node, or ectopic focus. The site of ablation was decided according to the electrical signals and the catheter position. The success of the RF-A was confirmed by the interruption of the tachychardia, the change in the sequence of activation of the intracardiac signals, the regression of the preexcitation and the inability to reinduce tachycardia. RF-A was succesful in 81 percent of the patients; 88 percent in those with a left AP 56 percent in those with a right arterial obstruction, one with a minimal pneumothorax and one with cardiac tamponade. During a follow up of 16.6 months there was no relapse nor late complications. We conclude that RF-A is a safe and effective procedure in pediatric patients with SVT
Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Adolescent , Tachycardia, Supraventricular/therapy , Catheter Ablation/methods , Catheter Ablation/adverse effects , Electrophysiology/methodsABSTRACT
La ablación por radiofrecuencia de haces paraespecíficos es un aterapia muye efectiva para el tratamiento de las taquicardías paroxíticas supraventriculares. Con el objeto de evaluar la utilidad del electrograma local en la identificación del sitio correcto para efecturar la ablación por radiofrecuencia, se analizaron las características de éstos en 20 pacientes con haces paraespecíficos fulgurados exitosamente. 16 pacientes tenían un haz paraespecífico izquierdo (10 ocultos), 2, haz paraespecífico anteroseptal y 1, un haz paraespecífico lateral derecho. En 15 pacientes la fulguración se realizó durante taquicardia paroxítica supraventricular y en 5, durante ritmo sinusal. En los 20 electrogramas analizados, el hallazgo más frecuente fue el de complejos fusionados. Se registró un probable electrograma de Kent en 3 pacientes fulgurados en taquicardia y en 4 pacientes fulgurados en ritmo sinusal. Pensamos que ninguna de las características del electrograma local tiene un valor predictivo alto para precisar el sitio de la fulguración exitosa
Subject(s)
Humans , Male , Female , Child, Preschool , Adolescent , Adult , Middle Aged , Electrocardiography/methods , Electrocoagulation/methods , Catheter Ablation/methods , Bundle of His/surgery , Predictive Value of Tests , Tachycardia, Paroxysmal/surgery , Neural PathwaysABSTRACT
La taquicardia auricular es una causa de taquicardia paroxística supraventricular que puede originarse en relación a un circuito de reentrada intraauricular o por la existencia de uno o múltiples focos de automatismo anormal. Esta última forma de taquicardia se denomina como taquicardia auricular ectópica (TAE) y se caracteriza porque suele ser resistente a tratamiento antirrítmico y porque en caso de tener carácter incesante puede llevar a insuficiencia cardíaca. En los últimos años se han desarrollado diversas alternativas de tratamiento no farmacológico. En la presente publicación presentamos el caso clínico de una mujer con TAE derecha que fue fulgurada con radiofrecuencia en forma exitosa
Subject(s)
Humans , Female , Pregnancy , Adult , Catheter Ablation/methods , Electrocoagulation/methods , Tachycardia, Ectopic Atrial/surgery , Atenolol/therapeutic use , Diagnosis, Differential , Electrocardiography , Electrophysiology , Femoral Vein/physiology , Pregnancy Complications, Cardiovascular/drug therapy , Tachycardia, Ectopic Atrial/diagnosis , Tachycardia, Ectopic Atrial/drug therapy , Tachycardia, Ectopic Atrial/etiology , Tachycardia, Paroxysmal/complicationsABSTRACT
Atrioventricular nodal reentry tachycardia (AVNRT) is one of the most mechanisms of paroxysmal supraventricular tachycardia. In these patients tachycardia is maintained due to anterograde conduction through a slow pathway and retrograde conduction to the atrium via a fast pathway. We present here our experience in ablation of the slow pathway. Since January 1993, 30 consecutive patients with AVNRT underwent attempted catheter ablation of the slow pathway. Mean age was 37ñ3.7 years. All patients had symptomatic tachycardia and six had history of syncope. Electrophysiological studies revealed AVNRT in all patients, in addition, 2 patients had a left accesory pathway. Slow pathway ablation was performed with Mansfield 7 F catheter, guided by both fluoroscopic positioning and endocardial signals. A mean of 13 burst were applied. In the 30 patients conduction though the slow pathway was interrupted and thus tachycardia was no longer inductible. Retrograde conduction post ablation was evaluated in 17 of the 30 patients, significant changes were observed in three of them. One patient developed second degree AV block and a permanent pacemaker was implanted. Another patient had recurrence of tachycardia three months post ablation. After a second attempt she is arrhythmia free. Patients have been followed for a mean of 15.7ñ2.5 months and are asymptomatic in the absence of antiarrhythmic therapy
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Tachycardia, Atrioventricular Nodal Reentry/surgery , Catheter Ablation/methods , Tachycardia, Atrioventricular Nodal Reentry/physiopathology , Electrophysiology/methodsABSTRACT
The permanent form is a variety of functional reciprocating tachycardia that is refractory to medical treatment. The anterograde arm of the circuit is formed by the His Purkinje bundle and the retrograde conduction is through a slow conduction accesory atrioventricular pathway. We report five patients with this type of arrhythmia, subjected to electrophysiological assessment. Their mean age was 37 years, all suffered from palpitations and several medical treatments had failed. During tachycardia, electrocardiogram had a negative P wave in inferior leads and RP interval was bigger than PR interval. Accesory Pathway were located in the right postero-septal region in three patients, in the left postero-septal region in one and in the left lateral in one. Specific bundle fulguration was succesfully attempted in four patients, in whom arrythmias did not recur without medical treatment
Subject(s)
Humans , Male , Adolescent , Adult , Middle Aged , Tachycardia, Ectopic Junctional/diagnosis , Heart Conduction System/physiopathology , Electrocardiography/methods , Electrocoagulation , Electrophysiology/methodsABSTRACT
La taquicardia incesante puede ser causada por diferentes mecanismos electrofisiológicos. Desde 1986, hemos estudiado 13 pacientes con taquicardia incesante, 9 hombres y 4 mujeres (edad promedio 35a). Diez pacientes habían recibido múltiples antiarrítmicos y 4 habían desarrollado insuficiencia cardíaca secundaria a taquicardia. Se efectuó estudio electrofisiológico en 11 pacientes, encontrando: 1) haces accesorios con conducción lenta y decremental en 5 pacientes. Se encontró un haz derecho posteroseptal en 3, un haz izquierdo posterolateral en 1 y un haz izquierdo posteroseptal en 1. La ablación por radiofrecuencia fue exitosa en 4 de estos 5 pacientes. 2) la taquicardia auricular ectópica fue el mecanismo de la arritmia en 4 pacientes. Se efectuó una resección quirúrgica exitosa del foco auricular en 1 paciente y ablación del his en otro. Fracasó la ablación por radiofrecuencia del foco auricular en un paciente. 3) Reentrada nodal atípica existió en 2 pacientes que fueron tratados con antiarrítmicos, cuando carecíamos de radiofrecuencia. 4) Un foco ectópico del his existía en un niño de 1 mes de edad, cuya arritmia se encuentra parcialmente controlada con drogas. 5) Un paciente tenía una taquicardia incesante atípica debida a un haz accesorio lento con intervalos A-H y H-V prolongados. Un intento de ablación con corriente continua se complicó de hemopericario que se trató con cirugía y la arritmia respondió posteriormente a antiarrítmicos. Por tanto, el estudio electrofisiológico es valioso en pacientes con taquicardia incesante y conduce a tratamiento exitoso con ablación por radiofrecuencia en muchos de ellos
Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Adolescent , Adult , Middle Aged , Electrophysiology/methods , Tachycardia/diagnosis , Catheter Ablation/methods , Anti-Arrhythmia Agents/therapeutic use , Arrhythmias, Cardiac/diagnosis , Bundle of His , Electrocardiography , ElectrocoagulationABSTRACT
El fenómeno de Wenckebach se caracteriza por una prolongación progresiva del intervalo P-R hasta que una onda P es conducida por bloqueo a nivel del nodo aurículo-ventricular. En estudios electrofisiológicos se ha demostrado que la estimulación ventricular puede conducirse hacia las aurículas con prolongación progresiva del intervalo V-A, lo que constituye una especie de Wenckebach retrógrado. Se presenta el caso de una mujer de 70 años que posterior a un infarto parietal izquierdo oclusivo presentó ritmo hisiano con conducción ventrículo-auricular, con fenómeno de Wenckebach retrógrado espontáneo y evidencias electrocardiográficas de doble vía nodal. Este conjunto de anormalidades electrofisiológicas no ha sido publicado previamente
Subject(s)
Humans , Female , Aged , Heart Block/complications , Heart Rate/physiology , Atrioventricular Node/physiology , Electrocardiography , Heart Conduction System/physiology , Infarction/complicationsABSTRACT
The replacement of muscle by fibrous and adipose tissue leads to arrhythmogenic right ventricular dyaplasia. We report the clinical features and therapeutic options of a 50 years old male with the disease followed during 12 years. The latter included pharmacological therapy, surgical pseudoaneurysmal resection and radiofrequency fulguration of a second arrhythmogenic focus that appeared 10 after the surgical procedure. The patient remained asymptomatic after each therapy, until the disease progressed again. This follow up is one of the longest reported and documents the disease's clinical presentation, evolution and treatment