Hemostatic disturbances associated with implantation of an artificial heart

Coagulation and platelet parameters have been assessed following implantation of a Jarvik 7 artificial heart. Initially an ongoing intravascular coagulation could not be overcome with heparin and coumarin. The in vivo formation of thromboxane A2 (as monitored by measurement of the major urinary metabolite) was increased 3-4 fold. Administration of aspirin every second to third day reduced the thromboxane formation dramatically. In parallel to this, the intravascular coagulation subsided, the demand for heparin decreased considerably and the clinical condition of the patient improved. These events provide evidence for a direct link between thromboxane formation and the coagulation cascade. The thromboxane formation was insufficiently suppressed around the 110th postoperative day. Two weeks later the patient suffered a cerebral embolus, followed by a bleeding in the embolized area. This case illustrates the applicability of antiplatelet treatment when the need for efficient antithrombotic treatment is especially pronounced. Aspirin, however, is not the ideal drug for this purpose.