Initial acute in vivo performance of the Cleveland Clinic PediPump left ventricular assist device.

The PediPump is a small ventricular assist device (VAD) with a hydraulic output range designed to support children from newborns to adolescents. The present report describes our initial evaluation of the PediPump as a left VAD in an acute sheep model. The PediPump was implanted in two sheep (50.8 and 62.7 kg). Pump speed was adjusted to achieve a flow of 2 L/min with the naturally occurring preload and afterload conditions to evaluate pump performance under a steady hemodynamic state for 4 hours. Upon completion, pump performance was evaluated under various blood pressure and heart rate conditions. During steady-state evaluations, the ascending aortic flow and pump speed varied slightly depending on systemic arterial pressure variations. During the hemodynamic manipulation studies, flows ranged between 0.5 and 3.2 L/min with pump speeds of 5,200-16,200 rpm and motor current of 0.06-0.75 A. The PediPump demonstrated good initial hemodynamic performance for use as an implantable left VAD. However, some depositions were detected at the time of explanation, mainly at the rear of the pump. We are continuing with further acute studies to evaluate pump performance in anticipation of beginning chronic studies to evaluate long-term biocompatibility.

A Surgically Treated Case of Acute Type A Dissection Subsequent to Chronic Dissection with 3-Channeled Descending Aorta Dissection / 日本心臓血管外科学会雑誌

A 41-year-old woman was admitted suffering from chest pain and dyspnea. We performed an emergency operation under a diagnosis of type A acute aortic dissection combined with type B chronic 3-channeled dissection on CT scan. The ascending aorta was replaced with woven Dacron graft under deep hypothermic circulatory arrest. Atrial inflow for cardiopulmonary bypass was initiated only through the femoral artery because the right axillary artery was stenotic. Neither cystic medial necrosis nor aortitis were recognized in pathological examination of the ascending aorta. Postoperative recovery was smooth and uneventful. Three-channeled aortic dissection tends to enlarge the false lumen, and has a high risk of rupture compared with the more common 2-channeled aortic dissection, therefore careful follow-up is needed in this patient. When acute type A dissection is complicated with 3-channeled chronic dissection, it is important to preoperatively assess the route of visceral blood supply, and to carefully select the cannulation site of extracorporeal circulation to prevent malperfusion.