Distinct pharmacologic substrate in lidocaine-sensitive, repetitive atrial tachycardia.

Lidocaine-sensitive, repetitive atrial tachycardia is an uncommon arrhythmia. The electrophysiologic substrate is still unknown, and the pharmacologic responses have not been fully explored. The aim of this study was to investigate the effects of intravenous adenosine and verapamil in patients with lidocaine-sensitive atrial tachycardia. In 9 patients with repetitive uniform atrial tachycardia, the response to intravenous adenosine (12 mg), lidocaine (1 mg/kg body weight), and verapamil (10 mg) were sequentially investigated. Simultaneous 12-lead electrocardiogram (ECG) was recorded at baseline and continuously monitored thereafter. Tracings were obtained at regularly timed intervals right after the administration of each drug to evaluate changes in the arrhythmia characteristics. Repetitive atrial tachycardia was abolished by intravenous lidocaine in the 9 patients within the first 2 minutes after the end of injection. Adenosine suppressed the arrhythmia in 2 patients and shortened the runs of atrial ectopic activity in 1 patient, while verapamil was effective in 2 patients, 1 of them insensitive to adenosine and the other 1 sensitive to this agent. In 5 patients, the arrhythmia was abolished by radiofrequency ablation at different sites of the right atrium. Lidocaine-sensitive atrial tachycardia may eventually be also suppressed by adenosine and/or verapamil. This suggests that this enigmatic arrhythmia may be caused by different underlying electrophysiologic substrates and that at least in some cases, delayed afterdepolarizations seem to play a determining role.

[Evolution of acute myocardial infarction treatment in Argentina from 1987 to 2005]. / Evolución del tratamiento del infarto agudo de miocardio en la Argentina desde 1987 a 2005.

In Argentina, one out of three deaths is of cardiovascular origin and acute myocardial infarction (AMI) is one of the most aggressive and frequent. In our country epidemiological data related to infarction are scarce. Various surveys and reports have been carried out in the past 25 years by different scientific societies, which, even though they provide valuable information, enclose only a small range of the population with access to high complexity centers. Though these records show a gradual increase in the rate of reperfusion, this has not resulted in a mortality reduction. This review is committed to provide all available information about the AMI in Argentina, in order to provide the necessary resources to the right diagnosis and therapeutic handling of this disease.

Evolución del tratamiento del infarto agudo de miocardio en la Argentina desde 1987 a 2005 / Evolution of acute myocardial infarction treatment in Argentina from 1987 to 2005

En la Argentina, una de cada tres muertes es de origen cardiovascular y el infarto agudo de miocardio (IAM) es una de sus presentaciones más agresivas y frecuentes. Sin embargo, en nuestro país los datos epidemiológicos relacionados al infarto son escasos. Diversas encuestas y registros se han realizado en estos últimos 25 años por las diferentes sociedades científicas, las cuales, si bien aportan valiosa información, sólo representan a una parte de la población con posibilidades de acceso a centros de alta complejidad. Los datos proporcionados por estos registros evidencian un aumento progresivo en la tasa de reperfusión; sin embargo, esto no se tradujo en una reducción de la mortalidad. Esta revisión tiene como objetivo aportar toda la información disponible sobre el IAM en la Argentina, y busca identificar los recursos necesarios para lograr un adecuado manejo diagnóstico-terapéutico de esta enfermedad.

In Argentina, one out of three deaths is of cardiovascular origin and acute myocardial infarction (AMI) is one of the most aggressive and frequent. In our country epidemiological data related to infarction are scarce. Various surveys and reports have been carried out in the past 25 years by different scientific societies, which, even though they provide valuable information, enclose only a small range of the population with access to high complexity centers. Though these records show a gradual increase in the rate of reperfusion, this has not resulted in a mortality reduction. This review is committed to provide all available information about the AMI in Argentina, in order to provide the necessary resources to the right diagnosis and therapeutic handling of this disease.