RESUMO
BACKGROUND: Intraventricular resynchronization with pacemakers is a promising therapy for patients with refractory cardiac failure and intraventricular conductions delay. However its long term effects are not well known. AIM: To report the results of this therapy in patients with cardiac failure. PATIENTS AND METHODS: Fourteen patients (11 male), whose mean age was 68 years, with a severe and refractory cardiac failure, have been treated in our unit using intraventricular resynchronization with pacemakers. Eight had a coronary heart disease and six a dilated myocardiopathy. The pacemaker was implanted transvenously, with conventional stimulation in atrium and right ventricle. The left ventricle was stimulated through an epicardial vein, accessed through the coronary sinus. RESULTS: In one patient the high thresholds did not allow a left ventricular stimulation. In the other 13 patients, a clinical improvement was observed in 11 (85 per cent), that has been sustained for a mean of 8.2 months. The ejection fraction improved form 23.5 to 32.4 per cent (p < 0.001), the 6 min walking test improved from 347 to 437 m (p = 0.003) and the functional capacity changes from 3.3 to 2.7 (p < 0.001). Three patients died during follow up. One was the patient in whom the stimulation failed and two had a sudden death. No complications of the procedure were observed. CONCLUSIONS: In this series, intraventricular resynchronization with pacemakers was effective in 11 of 13 patients, improving functional capacity and ejection fraction. Sudden death could be avoided adding a defibrillator to the pacemaker system.
Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estimulação Cardíaca Artificial/métodos , Cardiomiopatia Dilatada/terapia , Doença das Coronárias/terapia , Disfunção Ventricular/fisiopatologia , Marca-Passo Artificial , Resultado do Tratamento , Volume SistólicoRESUMO
BACKGROUND: Implantable defibrillators are the most effective means to prevent sudden death in patients with malignant ventricular tachyarrhythmias. The availability of this type of devices is limited in Chile, due to their high price. AIM: To report the first patients treated with implantable defibrillators in our hospital. PATIENTS AND METHODS: Nine males and one female aged 13 to 65 years old are reported. Three presented with ventricular fibrillation (presenting out of the hospital in three) and the rest had ventricular tachycardia resistant to drugs or radiofrequency ablation. RESULTS: All implants were performed using intracardiac electrodes. The generator was implanted in the pectoral region in nine and in the abdomen in one. A successful defibrillation was obtained with less than 15 J in four patients, with 20 J in three and with 24 J in three. There were no complications during the procedure. After a 12 months follow up, four patients have been treated by the implantable device. One of these subjects had a ventricular fibrillation in two occasions. One patient died of a bronchopneumonia two years after the implant. CONCLUSIONS: Implantable defibrillators are an effective therapy for the treatment of malignant ventricular arrhythmias with a high risk of sudden death.
Assuntos
Desfibriladores Implantáveis , Taquicardia Ventricular/terapia , Adolescente , Adulto , Idoso , Morte Súbita Cardíaca/prevenção & controle , Eletrocardiografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fibrilação VentricularRESUMO
We report a 47 years old male who was recuperated from a sudden death, and in whom the cardiological assessment showed a right bundle branch block and a fluctuating ST segment elevation V1 to V3. During the electrophysiological study, a polymorphic tachycardia and a ventricular fibrillation were induced. Procainamide administration enhanced ST segment alterations in right precordial leads, and isoproterenol normalized the EKG. All these disturbances are similar to the condition described by Brugada brothers. The patient was treated with an internal implantable defibrillator, without the use of antiarrhythmic drugs and is well after four months of follow up.
Assuntos
Morte Súbita Cardíaca/etiologia , Ressuscitação , Fibrilação Ventricular/complicações , Bloqueio de Ramo/complicações , Bloqueio de Ramo/terapia , Desfibriladores Implantáveis , Eletrocardiografia , Humanos , Masculino , Pessoa de Meia-Idade , SíndromeRESUMO
A great deal of interest has received atrial fibrillation, the most common arrhythmia in adults, due to its complications and difficult treatment its most dreaded complication is atrial thrombi formation with the subsequent risk of embolization. There are several reports defining risk factors for embolic complications and the usefulness of anticoagulants for their prevention. We review the state of the art of anticoagulation in atrial fibrillation not associated to rheumatic valvulopathy. We also give tools to assess embolic risk and to determine the anticoagulant choice for the different presentation forms of atrial fibrillation.
Assuntos
Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Tromboembolia/prevenção & controle , Fatores Etários , Arritmia Sinusal/prevenção & controle , Doença Crônica , Ensaios Clínicos como Assunto , Cardioversão Elétrica , Humanos , Metanálise como Assunto , Fatores de RiscoRESUMO
Most cases of atrial fibrillation are converted with antiarrhythmic medications or external electric defibrillation. However, in some refractory patients, an internal transcatheter defibrillation must be attempted. We report a 50 years old male with an atrial fibrillation of one year duration that was refractory to pharmacological treatment and in whom external cardioversion was unsuccessful. After the application of a bifasic shock of 10 joules between a catheter in the right atrium and another one located at the coronary sinus, the patient was converted to sinus rhythm. At two months of follow up, the patient continues in sinus rhythm.
Assuntos
Fibrilação Atrial/terapia , Desfibriladores Implantáveis , Cardioversão Elétrica/métodos , Doença Crônica , Cardioversão Elétrica/instrumentação , Seguimentos , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
We measured plasma concentrations of amiodarone and desethylamiodarone by HPLC in 44 outpatients aged 24 to 67 years old (21 male), receiving the drug during at least three months. The drug was indicated for supraventricular arrhythmias in 37 patients and ventricular arrhythmias in seven. Plasma concentrations of amiodarone, desethylamiodarone and their ratio were 1.71 +/- 0.82, 0.85 +/- 0.42 micrograms/ml and 2.02 respectively, for a mean daily dose of 223 +/- 88 mg. In 41 patients, arrhytmias were successfully treated. These patients received a mean daily dose of 220 +/- 86 mg and concentrations of amiodarone, desethylamiodarone and their ratio were 1.75 +/- 0.86, 0.88 +/- 0.45 micrograms/ml and 1.99 respectively. In three patients with treatment failure, receiving a daily dose of 257 +/- 115 mg, these figures were 1.2 +/- 0.3, 0.5 +/- 0.1 micrograms/ml and 2.4 respectively. We conclude that our patients had lower plasma concentrations of desethylamiodarone and higher amiodarone/desethylamiodarone ratios than those reported in other countries.
Assuntos
Amiodarona/uso terapêutico , Arritmias Cardíacas/tratamento farmacológico , Adulto , Idoso , Amiodarona/análogos & derivados , Amiodarona/sangue , Cromatografia Líquida de Alta Pressão , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Nonpharmacological methods are a novel therapeutic option for tachiarrhythmias. Transcatheter ablation or surgery can cure many arrhythmias, avoiding the collateral effects of antiarrhythmic drugs. Likewise, implantable defibrillators, have changed life expectancy of patients with high risk arrhythmias or sudden death survivors. However, the high cost and sophistication of these methods, preclude their widespread use, thus limiting the number of patients that can be benefited. This article reviews the main nonpharmacological techniques for treatment of arrhythmias, their results and complications.
Assuntos
Ablação por Cateter/métodos , Taquicardia/cirurgia , Contraindicações , Desfibriladores Implantáveis , Eletrofisiologia , Humanos , Prognóstico , Fatores de Risco , Taquicardia/fisiopatologia , Taquicardia Ventricular/cirurgiaRESUMO
A simple specific and sensitive high pressure liquid chromatography method (HPLC) to measure amiodarone and desethylamiodarone is described. The plasma sample is deproteinized with acetonitrile and a 50 ul aliquote run in the HPLC system with reverse phase column (C-18). Methanol-ammonium hydroxide is used to separate and spectrophotometric measurements are read at 254 nm.95% of the drug present in plasma is extracted with this method, with a sensitivity of 0.03 ug/ml and a day to day variation under 3%. Preliminary measurements were analyzed in 14 subjects receiving amiodarone for treatment of supraventricular arrhythmia. With a mean dose of 267 +/- 116 (SD) mg/day, plasma levels of 1.3 +/- 0.6 ug.ml for amiodarone and 0.9 +/- 0.5 mg/ml for desethylamiodarone were obtained.
Assuntos
Amiodarona/análogos & derivados , Amiodarona/sangue , Cromatografia Líquida de Alta Pressão , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e EspecificidadeRESUMO
Normal heart contraction was studied in 20 healthy subjects (14 males and 6 female, mean age 33 years). Rest radioventriculography and phase analysis were used. Ejection fraction was 66 +/- 7% for the LV and 53 +/- 7% for the RV (p < 0.0001). Peak filling rates in the first third of diastole were 1.6 +/- 0.6 EDV/sec for the LV and 0.7 +/- 0.3 EDV/sec for RV (p < 0.0001). Time to peak filling rate normalized for heart rate was 180 +/- 52 ms for the LV and 203 +/- 60 ms for the RV (p = 0.05). Filling fractions were 23 +/- 10% and 9 +/- 3%, respectively (p < 0.0001). Segmental motility was normal in all subjects. Phase analysis revealed faster emptying of the left atrium with phase angles of 171 +/- 13 degrees in the LA and 185 +/- 12 degrees in the RA (p = 0.00007). This difference may be related to faster diastolic events in the left ventricle. Phase angles for the LV and RV were -8.75 +/- 3 and -9.44 +/- 5 degrees, respectively (NS). We conclude that activation occurs earlier in the left atrium, proceeds through the septum and then synchronically over both ventricles.