[The sympathetic-adrenal system in mitral heart defects in patients of different ages studied by the use of a specific L-DOPA test].

As many as 59 patients aged 35 to 74 years suffering from mitral valvular disease (MVD) were examined for excretion of dopamine (DA), noradrenaline (NA) and adrenaline, parameters indicating the activity of the sympathoadrenal system. Administration of L-DOPA brought about a significant increase of excretion of all catecholamines in all the patients under 59 years and in those aged 60 to 74 years. In patients with stage I and IIA heart failure, DA excretion rose 50-fold in response to L-DOPA administration, in those with stage IIB and III, 17-fold (p less than 0.001). In patients suffering from MVD, no age-associated differences were revealed in the levels of catecholamines and ICM. In patients suffering from MVD with the predominance of stenosis and in those with stage I and IIA heart failure, background excretion of NA was significantly higher than in patients suffering from MVD with the predominance of heart failure (p less than 0.01). Administration of L-DOPA was followed by an appreciable increment of NA exactly in patients suffering from MVD with the predominance of stenosis (p less than 0.001). In the majority of patients with stage III heart failure refractory to multimodality treatment, the L-DOPA test revealed the smallest increment of DA; its excretion rose only 12-fold. Therefore, the progress of heart failure entails a decrease of the reserve potentialities of the sympathoadrenal system, marked by less output of its mediators.