Despite the increasing use of left ventricular assist devices for patients with end-stage congestive heart failure, no implantable, centrifugal right ventricular assist devices (RVADs) are available ...for those patients with significant right ventricular failure. The DexAide RVAD was developed to provide an implantable RVAD option to surgeons. The aim of this study was to evaluate pump performance in an acute in vivo model. The DexAide RVAD, developed as a modified CorAide left ventricular assist device, was implanted between the right ventricle and the pulmonary artery in four healthy calves. Pump speed was varied from 1800 rpm to 3600 rpm. RVAD performance was analyzed acutely at baseline and under conditions of low circulating volume, high contractility, high pulmonary arterial pressure, vasodilation, and low contractility. Pump flow was well maintained even under conditions of high pulmonary arterial pressure and vasodilation, with the exception of low circulating volume. Under all conditions, pulmonary arterial pressures were not affected by changing pump speed. The DexAide RVAD demonstrated acceptable hemodynamic characteristics for use as an implantable RVAD in the initial acute studies. Further studies are ongoing to examine the biocompatibility of the pump under chronic conditions.
Myocardial salvage through coronary sinus intervention has been documented. The AutoRetroPerfusion Cannula is a novel device that is able to perfuse the coronary bed retrogradely through the coronary ...sinus with arterial blood generated from a peripheral artery with no need for a pump. The cannula consists of a distal end that, once secured in the coronary sinus, opens an umbrella-like membrane to create pressure in the coronary sinus, and at the same time has small channels directed backwards to the right atrium to provide pressure relief. The cannula is introduced from the axillary vein under local anesthesia and the proximal end, which consists of a graft, is anastomosed to the axillary artery to start autoperfusion once the distal end is secured in the coronary sinus and the occluding membrane is open. The AutoRetroPerfusion Cannula was tested in the in vitro mock loop under 50-120 mm Hg of proximal pressure and 50, 100, and 150 ml/min of total flow in the cannula. We were able to achieve the nominal design point of 40-80 mm Hg of distal pressure and 50-150 ml/min of distal flow by adjusting the number, diameter, and length of the small backwards channels.
Living-donor liver transplant for hepatocellular carcinoma located on hepatocaval confluence or in contact with the inferior vena cava is technically challenging, and candidates for this kind of ...procedure should be carefully selected. It is difficult to rule out major vascular invasion except after hepatectomy and histologic examination; in addition, the possible dissemination of cancer cells during recipient hepatectomy is a considerable risk. Herein, we report the first case in Saudi Arabia of right lobe living-donor liver transplant combined with inferior vena cava reconstruction using cryopreserved iliac vein graft after en bloc resection of the liver with part of the diaphragm, anterior wall of retrohepatic inferior vena cava, and a 5-cm hepatocellular carcinoma in segment 7. Our patient achieved so far 3-year disease-free survival. Tumor recurrence and risk of thrombosis related to inferior vena cava reconstruction are the main concerns; therefore, long-term follow-up of those patients is mandatory.
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