Effect of milrinone therapy on splanchnic perfusion after heart transplantation

Milrinone is a selective inhibitor of the cAMP-specific phosphodiesterase III isoenzyme in myocardium and vascular smooth muscle. Milrinone administration following heart transplantation is routine practice. The purpose of this study was to evaluate the influence of milrinone therapy on splanchnic perfusion following heart transplantation.

There were 12 patients (10 males and 2 females) with a mean age of 42 ± 12 who underwent heart transplantation. Milrinone parenteral following surgery was started after surgery and continued for the next 67 ± 4 h. Repeated Swann-Ganz measurements and control transthoracic echocardiography were performed. Blood samples were taken to estimate level of lactic acid (LA), liver transaminases, serum amylase, and GFR ratio.

The mean time of milrinone administration was 67 ± 4 h. The serum LA increase following milrinone discontinuation was 1.7 ± 0.7 mmol/dm(3) vs. 3.8 ± 0.9 mmol/dm(3), (p<0.0001). The serum AST increase following milrinone discontinuation was 79 ± 30 IU/L vs. 135 ± 55 IU/L, p<0.04). We found a significant increase of blood ALT (29 ± 9 IU/L vs. 60 ± 23 IU/L) (p<0.0002) after milrinone withdrawn. There was a progressive increase in serum amylase levels after milrinone was withdrawn (80.6 ± 29 IU/L vs. 134 ± 45 IU/L, p<0.05).

Milrinone withdrawal during the postoperative period was associated with deterioration of splanchnic perfusion, as shown by a transient increase in lactic acid and serum increase of aminotransferases (ALT/ASP) concentration and amylase activity. The study results show the extracardiac effects of milrinone therapy.