RESUMEN
Interatrial blocks (IABs) are well described and accepted in the scientific community. In the last four decades major discoveries were made including its physiopathology, ECG presentation, classification and association with atrial tachyarrhythmias (advanced IAB). This article will briefly review the state of the art on the understanding of advanced IAB as an electrical substrate for atrial tachyarrhythmias as well as the future directions.
Asunto(s)
Arritmias Cardíacas/fisiopatología , Atrios Cardíacos/fisiopatología , Sistema de Conducción Cardíaco/anomalías , Sistema de Conducción Cardíaco/fisiopatología , Taquicardia Supraventricular/fisiopatología , Síndrome de Brugada , Trastorno del Sistema de Conducción Cardíaco , Fenómenos Electrofisiológicos , Humanos , SíndromeRESUMEN
BACKGROUND: Low-molecular-weight heparins are attractive alternatives to unfractionated heparin (UFH) for management of unstable angina/non-Q-wave myocardial infarction (UA/NQMI). METHODS AND RESULTS: Patients (n=3910) with UA/NQMI were randomized to intravenous UFH for >/=3 days followed by subcutaneous placebo injections or uninterrupted antithrombin therapy with enoxaparin during both the acute phase (initial 30 mg intravenous bolus followed by injections of 1.0 mg/kg every 12 hours) and outpatient phase (injections every 12 hours of 40 mg for patients weighing <65 kg and 60 mg for those weighing >/=65 kg). The primary end point (death, myocardial infarction, or urgent revascularization) occurred by 8 days in 14.5% of patients in the UFH group and 12.4% of patients in the enoxaparin group (OR 0.83; 95% CI 0.69 to 1.00; P=0. 048) and by 43 days in 19.7% of the UFH group and 17.3% of the enoxaparin group (OR 0.85; 95% CI 0.72 to 1.00; P=0.048). During the first 72 hours and also throughout the entire initial hospitalization, there was no difference in the rate of major hemorrhage in the treatment groups. During the outpatient phase, major hemorrhage occurred in 1.5% of the group treated with placebo and 2.9% of the group treated with enoxaparin (P=0.021). CONCLUSIONS: Enoxaparin is superior to UFH for reducing a composite of death and serious cardiac ischemic events during the acute management of UA/NQMI patients without causing a significant increase in the rate of major hemorrhage. No further relative decrease in events occurred with outpatient enoxaparin treatment, but there was an increase in the rate of major hemorrhage.
Asunto(s)
Angina Inestable/tratamiento farmacológico , Enoxaparina/uso terapéutico , Fibrinolíticos/uso terapéutico , Heparina/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Terapia Trombolítica , Enfermedad Aguda , Anciano , Angina Inestable/complicaciones , Angina Inestable/cirugía , Anticoagulantes/administración & dosificación , Anticoagulantes/efectos adversos , Anticoagulantes/uso terapéutico , Creatina Quinasa/sangre , Método Doble Ciego , Electrocardiografía , Urgencias Médicas , Enoxaparina/administración & dosificación , Enoxaparina/efectos adversos , Europa (Continente)/epidemiología , Inhibidores del Factor Xa , Femenino , Fibrinolíticos/administración & dosificación , Fibrinolíticos/efectos adversos , Hemorragia/inducido químicamente , Heparina/administración & dosificación , Heparina/efectos adversos , Humanos , Isoenzimas , Tablas de Vida , Masculino , Persona de Mediana Edad , Mortalidad , Infarto del Miocardio/epidemiología , Infarto del Miocardio/etiología , Infarto del Miocardio/prevención & control , Infarto del Miocardio/cirugía , Revascularización Miocárdica/estadística & datos numéricos , América del Norte/epidemiología , Tiempo de Tromboplastina Parcial , Recurrencia , Seguridad , América del Sur/epidemiología , Terapia Trombolítica/efectos adversos , Resultado del TratamientoRESUMEN
The electrophysiologic characteristics of the denervated human heart were assessed in 20 cardiac transplants recipient from the Cardiology Department, at the Hospital of San Pablo, Barcelona, Spain. We studied the donor and the recipient sinus node function at rest and exercise test. Holter recording of 24 hours was performed in a few cases. At rest, in 14 patients the intrinsic heart rate of the donor atrium was slower when we used the technique of José. When we analyzed all the results we did not find statistical differences in the heart rate of either: the donor or the recipient atria (r = 0.58, p less than 0.01). However we observed a marked increase in heart rate of the donor with exercise test and normal activity (Holter), probably reflecting an increase in circulating catecholamines (exercise test: base-line 116 +/- 16 vs maximum exercise 140 +/- 10, p less than 0.001; Holter: minimal rate 64 +/- 9.66 vs maximal rate 112 +/- 23, p less than 0.001). We also describe the cardiac arrhythmias including two sudden deaths associated with ventricular tachyarrhythmias and in five patients sinus node disfunction in relation with episodes of acute rejection. We concluded that is important to perform a standard 12 lead electrocardiogram, exercise testing, Holter recording and electrophysiologic study as part of the ongoing routine evaluation of surviving cardiac transplant patients.