The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation
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J. Heart Lung Transplant. · Oct 2005
Nutrition assessment and management of left ventricular assist device patients.
Nutrition evaluation and support is an integral component of left ventricular assist device (LVAD) therapy. Malnutrition in the LVAD patient contributes to a host of post-operative problems, such as infection and limited functional capacity, which compromise long-term outcomes. ⋯ An interdisciplinary approach, including a nutrition support team, is desirable to manage these patients effectively. This article reviews essential aspects regarding nutrition management of these patients.
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J. Heart Lung Transplant. · Oct 2005
Airway vascular changes after lung transplant: potential contribution to the pathophysiology of bronchiolitis obliterans syndrome.
Bronchiolitis obliterans syndrome (BOS) remains the primary factor limiting successful lung transplantation. In asthma and lung transplantation BOS-increased sub-mucosal vascularity has been shown to contribute to airflow limitation. Vascularity has 2 components: sprouting angiogenesis (more vessels) and microvascular enlargement (larger vessels). We hypothesized that the lack of a reanastomosed bronchial arterial blood supply at the time of transplant might stimulate angiogenesis and be a risk factor for subsequent BOS. ⋯ This study suggests early and persistent airway vasculature changes occur in lung transplant recipients, mainly manifested as microvascular enlargement. Potentially this baseline change contributes to airway obstruction and also puts all lung transplant recipients at risk for further exponential loss of airway caliber with any subsequent airway inflammatory insult.
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J. Heart Lung Transplant. · Oct 2005
Left ventricular dysfunction after acute intracranial hypertension is associated with increased hydroxyl free radical production, cardiac ryanodine hyperphosphorylation, and troponin I degradation.
In addition to generating free radicals, stress-induced activation of the sympathetic nervous system results in hyperphosphorylation of the cardiac ryanodine receptor (RyR2)/calcium (Ca2+) release channel on the sarcoplasmic reticulum, causing leaky channels. These events may contribute to cytosolic Ca2+ overload and activation of Ca2+-dependent cytotoxic processes. Because myocardial dysfunction associated with intracranial hypertension is catecholamine mediated, we sought to determine in a rat model if hemodynamic changes are associated with an increase in oxidative stress, hyperphosphorylation of RyR2, and degradation of myofilament protein cardiac troponin I (TnI). ⋯ The present findings demonstrate that hemodynamic instability after intracranial hypertension is associated with oxidative stress and post-translational changes to RyR2 and TnI degradation. Despite this, the myocardial responsiveness to beta1 adrenergic stimulation is preserved in rats with depressed myocardial function.
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J. Heart Lung Transplant. · Oct 2005
High prevalence of pulmonary arterial thrombi in donor lungs rejected for transplantation.
Donor hypoxemia is a common reason for the rejection of lungs for transplantation. Organ donors are at high risk for venous thromboembolism. Pulmonary arterial thrombosis could contribute to donor hypoxemia. The primary objective of this study was to prospectively quantify the incidence of pulmonary arterial thrombosis in organ donors whose lungs were rejected for transplantation. The secondary objective was to better define the spectrum of histologic abnormalities in the same group of lungs. ⋯ Pulmonary arterial thrombosis and/or pulmonary infarction are very common in organ donors whose lungs are rejected for transplantation and might contribute to lung dysfunction both in lung donors and lung recipients. Further studies are needed to define the incidence of pulmonary arterial thrombosis in organ donors whose lungs are used for transplantation and to better assess the adverse clinical consequences of donor pulmonary arterial thrombosis in lung recipients.
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J. Heart Lung Transplant. · Oct 2005
Comparative StudyDifferential exercise performance on ventricular assist device support.
Ventricular assist devices (VADs) are approved for destination therapy because they improve survival in end-stage heart failure (HF). VADs are powered pneumatically or electrically. Pneumatic and electric left ventricular assist devices (LVADs) and biventricular assist devices (BiVADs) provide excellent hemodynamic support at rest, but differences in their effects on exercise tolerance are unclear. We sought to evaluate the effect of devices with varying operating parameters on exercise capacity. ⋯ HF patients supported with a pneumatic LVAD appear to have better exercise tolerance than those receiving an electric LVAD. Patients on LVAD support have better exercise tolerance than BiVAD-supported patients. This highlights the importance of right ventricular function to exercise tolerance in HF patients, and may have implications for future VAD design.