Natriuretic peptide measurements as part of the diagnostic work-up in pleural effusions: an emerging concept?

I n the 1950s and 60s, the possible role of the heart in the control of renal excretion of salt and water, and thereby of the extra cellular fluid volume, as well as the presence of specific granules within atrial muscle cells was recognised [1, 2]. Nevertheless, little attention was paid to the possibility of the existence of an endocrine cardiac natriuretic hormone system until the landmark experiments in the late 1970s by DE BOLD et al. [3], which led to the discovery of atrial natriuretic peptide (A-type natriuretic peptide; ANP) having potent natriuretic, diuretic and vasodilatator actions.