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Right sided circulatory failure (RSCF), a common complication after left ventricular assist device (LVAD) implantation, results in decreased systemic output due to diminished blood flow across the pulmonary vasculature. The authors hypothesized that creation of a venoarterial shunt (VAS) would decompress the right-sided circulation and improve systemic pressure and perfusion with significant arterial desaturation. An experimental model was created in which RSCF was induced acutely in a large animal (n = 6) by beta-blockade after LVAD placement. After VAS creation, hemodynamic and blood gas determinations were performed to compare non shunt and shunt states. After induction of heart failure after LVAD placement, VAS resulted in a 22% elevation in systemic blood pressure (p < 0.0001), a 36% elevation in cerebral blood flow (p = 0.02), and an 18% decrease in right sided filling pressures (p = 0.08). Systemic pH and aortic oxygen saturation remained unchanged from baseline. In a large animal model of RSCF after LVAD implantation, VAS improves systemic hemodynamics without a significant cost in arterial oxygenation to critical organs and without creating acid-base imbalance. Beside implementation, adjustable capabilities, easy removal and salutatory hemodynamic effects suggest that VAS may serve as a first line, short-term therapy for LVAD recipients who develop perioperative RSCF.

The authors reviewed the charts of 26 recipients of a left ventricular assist device to determine the incidence of fungal infections and the clinical course of these patients. Nine patients (35%) had positive fungal cultures. Of these, six had clinical infections and three were colonized asymptomatically. Three of the six infected patients (including one with mediastinal sepsis and another requiring left ventricular assist device replacement for intractable fungemia) underwent orthotopic heart transplantation after successful therapy. Of the remaining three, one died of a thromboembolic stroke (probably septic in nature), one died secondary to driveline rupture, and the third succumbed to culture-negative sepsis. Two of the colonized patients underwent transplantation, and the third succumbed to perioperative right sided circulatory failure and hypoxia. Positive fungal cultures were a common finding in our series. Because of a significant incidence of fungal infection-related morbidity, the authors revised their pre operative and post operative protocol to include: 1) 2 weeks of fluconazole therapy (200 mg intravenously daily) for patients receiving broad spectrum antibiotics and for those with evidence of preoperative fungal colonization; 2) daily dressing changes around drivelines; 3) daily nystatin swish and swallow; and 4) empiric fluconazole treatment for culture-negative sepsis. Using this protocol, three left ventricular assist device recipients received prophylactic fluconazole and had no evidence of fungal morbidity or mortality on short-term follow-up.

Left ventricular assist devices can be successfully used in the pediatric population if currently available devices are used appropriately. To highlight their management strategies, the authors' experience with pediatric left ventricular assist devices is reviewed, with case studies documenting options for device use. A retrospective study was conducted for all patients supported at the authors' institutions. Nine pediatric patients received devices during this time, with ages ranging from 12 days to 15 years. There was considerable size differences in our patients, with weights ranging between 2.5 and 73 kg. Either the Abiomed BVS 5000 (Abiomed Cardiovascular, Inc, Danvers, MA) or the Biomedicus centrifugal pump (Bio-Medicus, Inc, Eden Prairie, MN) were used for all patients. Patients were supported for an average of 5 days (range 1-11 days). Eight patients were successfully weaned from the device, with four undergoing transplant. Four patients were discharged and are long-term survivors, and one is still recovering post transplant. Neurologic sequelae were the most common complications in these patients, with four patients having events. Pediatric ventricular assist devices are limited because of size considerations, although current devices can be successfully used for bridging to recovery or transplantation. New devices are needed to meet the flow and size characteristics for pediatric patients. Successful use of assist devices, as has been recognized in adults, is possible in pediatric patients if these requirements are met.