A 23 month old boy with highly symptomatic tetralogy of Fallot (TOF) underwent repair. Inspite of cold Bretschneider cardioplegic solution twice the heart was beating soon after application of the cardioplegic solution each time. Soon after transfer to the intensive care unit the patient developed low cardiac output (LCO). The following days high doses of inotropic support ware necessary to maintain sufficient arterial pressure. The dosages of dobutamine (up to 49 micrograms/kg/min); norepinephrine (up to 5.28 micrograms/kg/min, and epinephrine (up to 16 micrograms/kg/min), respectively, were twice and three times as high as common maximum recommendations. After having recovered from acute renal failure requiring hemodialysis from the 5th to the 37th postoperative day the child was discharged 9 weeks after the intervention. The very unusual and interesting course of this boy is described and the form and grade of the inotropic support is discussed.