[Changes of alpha hANP concentration in arterial and coronary sinus blood during and after cardiopulmonary bypass].

Recent studies suggest that plasma levels of alpha-hANP may reflect the severity of heart failure, but mechanism whereby ANP secretion increase is not known. Changes in alpha-hANP concentration in the arterial (A-ANP) and coronary sinus blood (CS-ANP) during and after the cardiopulmonary bypass (CPB) were measured to investigate the role of ANP in patients undergoing cardiac surgery. Fifteen patients were divided into 2 group; Group I, valvular heart disease (n = 9), Group II, coronary artery disease (n = 6). Both A-ANP and CS-ANP were significantly higher in the Group I than Group II before and during CPB. The difference between two groups decreased and was insignificant after CPB. The CS-ANP was twice as high as A-ANP at simultaneous sampling point. Significant correlations between the changes in PCWP (delta PCWP) and delta A-ANP (p < 0.01), delta RAP and delta A-ANP (p < 0.02) and an inverse linear correlation between CI and A-ANP (p < 0.01) were observed. Not a significant correlation was found between ANP and urine volume, urinary sodium excretion and other renal functional parameters during and after CPB. Hypothermia and the use of mannitol in large quantities were considered to be factors. In the Group I, A-ANPs were also measured in the postoperative follow-up period. A-ANP remained elevated above 100 pg/ml in patients with poor and decreased below 100 pg/ml with good prognostic signs 3 to 6 months postoperatively. From these results, it is suggested that alpha hANP is secreted from the atrial wall to the coronary sinus vein and the levels of alpha-hANP in the perioperative and follow-up period after heart surgery, especially in the valvular heart disease, are considered to reflect the cardiac performance.