Pathomorphological study of the endocrine heart in various cardiovascular diseases.

Tissue of the endocrine heart was examined from patients undergoing open heart surgery for aorto-coronary bypass and correction of valve and septum diseases. The right auricular myoendocrine cells were studied with immunohistochemistry and electron microscopy for cardiac hormones (cardiodilatin = CDD-99-126, which is identical to alpha-human atrial natriuretic polypeptide = alpha-hANP). Furthermore, the pre- and postoperative blood samples were analysed by radioimmunoassay (RIA) combined with high pressure liquid chromatography (HPLC) to determine the plasma concentration and the molecular forms of circulating CDD-99-126/alpha-hANP. The results show that, depending on the status of the patient, differing quantities of CDD-IR (cardiodilatin immunoreactivity) are detected in the myoendocrine cells. This is also confirmed by the granularity of myoendocrine cells, as seen in the electron microscope. The ACB (aorto-coronary bypass) patients with normotonia exhibit, as a rule, the status of a normal endocrine heart. In mitral valve diseases, particularly in the combined vitia, prominent autophagolytic changes in myoendocrine cells are frequently seen. Pre- and postoperative blood shows only one circulating form of cardiodilatin which exhibits the characteristics of the 28 amino acid residues containing molecule CDD-99-126/alpha-hANP. The postoperative CDD content of blood plasma tends to decrease mainly in patients with successful treatment.