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Papel de los nitratos en el tratamiento de la enfermedad cardiovascular

Revista Espa de Cardiologia (Impact Factor: 3.2). 01/2006; 6(1):41. DOI: 10.1016/S1131-3587(06)74819-1

ABSTRACT Los nitratos orgánicos, en sus diferentes presentaciones, han constituido uno de los pilares para el tratamiento de las enfermedades cardiovasculares durante más de 100 años. Los nitratos son donadores de óxido nítrico; por tanto, su efecto primordial es el de la relajación del músculo liso endotelial. Producen dilatación venosa y arterial, por lo que reducen la precarga y la poscarga. Sus principales indicaciones son el tratamiento sintomático de la angina de esfuerzo estable, el síndrome coronario agudo, y la insuficiencia cardíaca aguda y crónica. Asimismo, añadidos a la terapia convencional en pacientes afroamericanos con insuficiencia cardíaca crónica, en asociación con la hidralazina, producen una reducción de la mortalidad. Su papel actual en pacientes de otras razas aún se desconoce.La principal limitación de esta terapia es el desarrollo de tolerancia, que conduce a la atenuación de los efectos farmacológicos antiisquémicos, antianginosos y hemodinámicos con la utilización continuada. En la práctica clínica, lo más conveniente para reducir al mínimo la tolerancia es utilizar la menor dosis necesaria y dejar un intervalo libre de nitratos, para permitir la recuperación del endotelio.For more than 100 years, organic nitrates, in one form or another, have formed one the central pillars of the treatment of cardiovascular disease. As nitrates are nitric oxide donors, their main effect is to induce endothelial smooth muscle relaxation. Nitrates induce both venous and arterial dilatation, thereby reducing both preload and afterload. They are principally indicated for the symptomatic treatment of stable angina, acute coronary syndromes, and acute and chronic heart failure. Moreover, nitrates also reduce mortality in Afro-americans when given with hydralazine as an addition to conventional therapy. Their role in other ethnic groups is unknown. The main limitation of nitrate therapy is that its continued use leads to the development of tolerance, with reductions in anti-ischemic and hemodynamic effects. Clinically, the most appropriate way of minimizing tolerance is to use the lowest acceptable dose and to introduce nitrate-free periods to enable recovery of the endothelium.

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