Tormenta eléctrica en síndrome de Brugada tratada exitosamente con infusión de isoproterenol / Electrical storm in Brugada syndrome successfully treated with isoproterenol. Report of a case

We report a 22-year-old male who experienced several episodes of syncope within a timeframe of few hours. In the emergency room, multiple ventricular fibrillation episodes where documented along with a type 1 Brugada ECG pattern. Isoproterenol in continuous infusion was started, normalizing the ECG and avoiding further arrhythmia recurrences. The patient was implanted with an automated defibrillator and discharged 3 days after admission.

Terapia de resincronización en pacientes con insuficiencia cardiaca: experiencia acumulada de 10 años / Cardiac resynchronization therapy in patients with heart failure: A 10-year experience

Background: Multiple randomized trials support the clinical benefits of cardiac resynchronization therapy (CRT) in patients with heart failure (HF) and ventricular dyssynchrony. Since the year 2000 this therapy has been increasingly used in Chile. Aim: To describe the clinical characteristics and follow-up of HF patients undergoing CRT in a single Chilean university hospital during the last 10 years. Patients and Methods: All patients undergoing CRT between 2000 and 2010 in our university hospital were included. Clinical and echocardiographic data were extracted from medical records and mortality causes were obtained from the National Identification Service. Results: A total of 252 patients underwent CRT during the study period. Seventy five percent were in New York Heart Associatin (NYHA) functional class III and mean ejection fraction was 29 ± 10%. Complete left bundle branch block was present in 55% and 20% had permanent atrial fibrillation (AF). Mean survival was 86% at 1 year and 82% of patients in NYHA class III-IV improved at least one functional class. Survival was poorer in patients with ischemic etiology (hazard ratio (HR) 1.48), functional class IV (HR 2.2), right bundle branch block (RBBB) (HR 3.1) and AF (HR 3.4). No survival differences were observed between patients with and without an implanted cardiodefibrillator. Conclusions: This series show good clinical outcomes, comparable to those reported in randomized trials. Predictors of worse survival included an ischemic etiology, functional class IV, RBBB and AF. Patients with a defibrillator had no better survival, which could be relevant in countries with limited health care resources.

[Electrical storm in Brugada syndrome successfully treated with isoproterenol. Report of a case]. / Tormenta eléctrica en síndrome de Brugada tratada exitosamente con infusión de isoproterenol.

We report a 22-year-old male who experienced several episodes of syncope within a timeframe of few hours. In the emergency room, multiple ventricular fibrillation episodes where documented along with a type 1 Brugada ECG pattern. Isoproterenol in continuous infusion was started, normalizing the ECG and avoiding further arrhythmia recurrences. The patient was implanted with an automated defibrillator and discharged 3 days after admission.

[Cardiac resynchronization therapy in patients with heart failure: a 10-year experience]. / Terapia de resincronización en pacientes con insuficiencia cardiaca: experiencia acumulada de 10 años.

BACKGROUND: Multiple randomized trials support the clinical benefits of cardiac resynchronization therapy (CRT) in patients with heart failure (HF) and ventricular dyssynchrony. Since the year 2000 this therapy has been increasingly used in Chile. AIM: To describe the clinical characteristics and follow-up of HF patients undergoing CRT in a single Chilean university hospital during the last 10 years. PATIENTS AND METHODS: All patients undergoing CRT between 2000 and 2010 in our university hospital were included. Clinical and echocardiographic data were extracted from medical records and mortality causes were obtained from the National Identification Service. RESULTS: A total of 252 patients underwent CRT during the study period. Seventy five percent were in New York Heart Associatin (NYHA) functional class III and mean ejection fraction was 29 ± 10%. Complete left bundle branch block was present in 55% and 20% had permanent atrial fibrillation (AF). Mean survival was 86% at 1 year and 82% of patients in NYHA class III-IV improved at least one functional class. Survival was poorer in patients with ischemic etiology (hazard ratio (HR) 1.48), functional class IV (HR 2.2), right bundle branch block (RBBB) (HR 3.1) and AF (HR 3.4). No survival differences were observed between patients with and without an implanted cardiodefibrillator. CONCLUSIONS: This series show good clinical outcomes, comparable to those reported in randomized trials. Predictors of worse survival included an ischemic etiology, functional class IV, RBBB and AF. Patients with a defibrillator had no better survival, which could be relevant in countries with limited health care resources.

[Experience in the use of a new endocardial stimulation electrode]. / Experiencia en el uso de un nuevo catéter electrodo de estimulación endocavitaria: Seguimiento a un año.

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.

[Radiofrequency ablation of ventricular tachycardia in a patient after surgery for Tetralogy of Fallot: case report]. / Fulguración con radiofrecuencia de taquicardia ventricular después de corrección quirúrgica de Tetralogía de Fallot: caso clínico.

Ventricular tachycardia is one of the most feared complications after surgical repair of Tetralogy of Fallot and it is associated with sudden death. We report a 26 years old female with a history of surgical repair of Tetralogy of Fallot at age of 4 year-old, who developed sustained ventricular tachycardia despite antiarrhythmic drugs. She was successfully treated with radiofrequency catheter ablation. Radiofrequency catheter ablation is a valid treatment for these patients.

[Chest pain and ST segment abnormalities in patients with accessory atrioventricular pathways. Report of three cases]. / Dolor torácico y alteración del segmento ST en pacientes con vías accesorias aurículo-ventriculares.

We report three patients with pre-excitation syndrome that resembled an acute coronary syndrome. A 65 years old woman, consulting in the emergency room for palpitations and retrosternal pain. EKG showed regular tachycardia and ST depression that reverted spontaneously after an episode of vomiting. A subsequent EKG demonstrated a pre-excitation syndrome and the accessory pathway was fulgurated. A 18 years old male presenting with tachycardia and chest pain elicited during exercise. An EKG showed a pre-excitation syndrome and ST segment elevation in V2 and V3. A coronary angiogram was normal. The accessory pathway successfully fulgurated. A 63 years old woman that presented tachycardia while exercising. She was subjected to an electrical cardioversion. An electrophysiological study showed an accessory pathway that was successfully fulgurated.

[Results of radiofrequency ablation of the inferior vena cava-tricuspid valve isthmus for atrial flutter]. / Flutter auricular: resultados inmediatos y alejados de la fulguración con radiofrecuencia del istmo cavo-tricuspídeo.

BACKGROUND: Radiofrequency ablation of the inferior vena cava-tricuspid valve isthmus relieves atrial flutter in 95% of cases. AIM: To evaluate the long term results of radiofrequency ablation of the inferior vena cava-tricuspid valve isthmus in atrial flutter. MATERIAL AND METHODS: Retrospective review of 86 patients with common atrial flutter, treated with radiofrequency ablation of the isthmus, while in sinus rhythm or flutter. Patients were contacted by telephone for a new clinical and electrocardiographic assessment, three to 40 months after the procedure. RESULTS: Of all the patients treated, five died and five were lost from follow up, thus 76 patients (mean age 56 years, 58 males) were contacted for reassessment. At the moment of the procedure, 51% had an underlying cardiac disease and 25% had high blood pressure. All referred palpitations, 25% had dyspnea, 84% were receiving antiarrhythmic drugs and 33% were on oral anticoagulants. Flutter was paroxystic in 83% and chronic in 17%. Fulguration was successful in all patients; one patient presented a high grade atrioventricular block as a complication of the procedure. At reassessment, 82% of patients were in sinus rhythm, 16% had atrial fibrillation and 2%, an atypical flutter. CONCLUSIONS: Radiofrequency fulguration is a safe and effective treatment of atrial flutter.

[Treatment of beneficiaries of the Chilean public health system with arrhythmias in a University Clinical Hospital]. / Experiencia de plan piloto para pacientes del FONASA portadores de arritmias atendidos en el Hospital Clínico de la Pontificia Universidad Católica de Chile.

BACKGROUND: The costs of medical care increase along with technological advances. Therefore, highly complex and expensive procedures should be performed in a limited number of institutions. AIM: To report the initial experience on electrophysiological studies performed to beneficiaries of a public health insurance system in Chile (FONASA). MATERIAL AND METHODS: An agreement was reached between the Electrophysiology Unit of the Clinical Hospital of the Catholic University and FONASA, to perform electrophysiological studies at a minimal cost, that only considered disposable materials and hospital stay. Thirty patients with supraventricular arrhythmias or ventricular arrhythmias without an associated cardiopathy, were attended using this agreement at the unit. RESULTS: In all treated patients, arrhythmias disappeared. Costs remained within the assigned budget, excepting occasional complementary tests. CONCLUSIONS: This pioneering experience demonstrated that it is possible that public health insurance systems can buy complex and expensive procedures to private hospitals.

[Paroxysmal tachycardia in a patient with a permanent form of junctional reciprocating tachycardia. A case report]. / Taquicardia recíproca de la unión auriculoventricular: características electrofisiológicas en un paciente con la variedad paroxística. Caso clínico.

Junctional reciprocating tachycardia is an atrioventricular reentrant tachycardia whose anterograde conduction occurs via the His Purkinje and the retrograde conduction via an accessory pathway with slow conduction. The most common form is incessant tachycardia but a paroxysmal form also exists. We report a 35 years old female with recurrent paroxysmal tachycardia, that underwent electrophysiological evaluation. A left posterolateral accessory pathway was documented. Reciprocating paroxysmal tachycardia was induced by electrical stimulation and a successful pathway ablation was performed.