[Coffee and caffeine - enemies or alliantes of a cardiologist?].

Caffeine is a widespread known psychoactive substance that is present mainly in coffee, tea, soft and energy drinks. As a natural methylopxanthine it blocks A1 and A2 adenosine receptors and in high doses inhibits the phosphodiesterase activity. Caffeine also decreases calcium ion accumulation in the mitochondria of cardiomyocytes. A clinical and experimental data indicates that the caffeine and coffee increase the arterial wall stiffness, blood pressure and endothelium-dependent flow mediated dilatation. Caffeine also elevates cholesterol and homocysteine blood level. Moderate coffee consumption decreases the mortality of the cardiac infarct. However, acceleration of acute ischemic cardiac disease correlates with high coffee intake. The metyloxantine easily crosses the blood-placenta barrier, and may induce intrauterine growth retardation. Due to chronotropic and inotropic activity it may induce fetal tachycardia and/or extrasystolic beats.