Biventricular Assist Device by the Berlin Heart as Bridge to Transplant in a 9-Year-Old Boy with Dilated Cardiomyopathy and Multiorgan Failure

We report on a 9-year-old boy who presented with end-stage heart failure due to idiopathic dilated cardiomyopathy 7 months after the initial diagnosis. On admission to the Pediatric Intensive Care Unit he showed massive right ventricular dilation with minimal contractility and severe left ventricular dysfunction in transthoracic echocardiography, permanent monomorphic ventricular tachycardia of 130/min, and an elevated BNP-level (887 pg/ml). Despite maximal medical treatment with amiodarone, diuretics, inotropes (dobutamine, milrinone, epinephrine, norepinephrine), and a course of thyrotardin and levosimendan the patient developed cardiogenic shock with multiorgan dysfunction syndrome (lactic acidosis, renal, respiratory and liver failure with coagulopathy and encephalopathy). Therefore a pulsatile paracorporeal biventricular assist device, the Berlin Heart pediatric®, was implanted under resuscitation.

With the exception of resternotomy for diffuse bleeding the early postoperative course was uneventful with all organ functions recovering rapidly and the boy being extubated after 3 days remaining on diuretics only.

Infectious complications included catheter-related sepsis with staphylococcus epidermidis perioperativly treated with vancomycin, and persistant colonization of the device with staphylococcus epidermidis, cultured from clots in removed pumps. Systemic signs of inflammation were associated with hyperfibrinogenemia initially making anticoagulation management difficult.

The anticoagulation protocol consisted of full systemic heparinization postoperativly followed by an overlapping combination of phenprocoumon and aspirin according to results of thrombelastogram and platelet aggregation test. Nevertheless extensive thrombus formation on the polyurethane valve surface of the artificial blood pumps occurred making the exchange of the pumps necessary twice. With addition of dipyridamole to the anticoagulation regimen and spontaneously decreasing plasma fibrinogen levels less clot formation was detectable later on. Fortunately the young boy did not experience neither thromboembolic nor bleeding complications. He is on the device for 4 months actually, pursuing normal daily activities within the hospital – and awaiting transplantation.

In conclusion the Berlin Heart pediatric allows long-term mechanical circulatory support with complete recovery from multiorgan failure and full mobilization. However this case illustrates the high risk of pump thrombosis and thromboembolic complications, especially in the initial phase due to hyperfibrinogenemia, requiring an aggressive anticoagulation therapy and monitoring.