Journal of Artificial Organs最新文献

In patients with left ventricular assist device (LVAD), concomitant mechanical valve is contraindicated for fear of thromboembolism. It is recommended that mechanical valves be replaced with biological valves or that mechanical valves be permanently closed when LVAD is indicated. Recently, a novel mechanical valve has proven safety in terms of valve thrombosis or thromboembolism in patients with valvular disease, though limited data is available regarding the performance of the valve in patients receiving LVAD therapy. In this report, we describe a case of successful bridge with extracorporeal LVAD to durable LVAD therapy without thromboembolism for postoperative cardiogenic shock after aortic root replacement using an On-X mechanical valve.

Genetic and numerous epidemiologic studies have identified lipoprotein (a) [Lp(a)] as a risk factor for atherothrombotic diseases. The structure of Lp(a) is similar to plasminogen and tissue plasminogen activator and it competes with plasminogen for its binding site, leading to reduced fibrinolysis. Furthermore, since Lp(a) stimulates the secretion of plasminogen activator inhibitor-1, it may lead to thrombogenesis. In this cross-sectional study, we aimed to investigate Lp(a) levels in patients with mechanical prosthetic valve thrombosis (MPVT). Blood samples for Lp(a) determination were obtained from 80 MPVT patients (median age: 48.5 (39-59.75) years; 47 male) and 75 age and sex matched controls (median age: 52 (39-63) years; 44 male) with normally functioning mechanical prosthetic valves. The Lp(a) levels in the PVT group were significantly higher than in the controls [22(16.2-39.4) vs. 6.9(2.9-24.6) mg/dL, p < 0.001]. Elevated Lp(a) levels, recent history of subtherapeutic anticoagulation, history of cerebrovascular accidents (CVA) and a low value of international normalized ratio on admission were found to be the independent predictors of PVT. Lp(a) levels above 19.6 mg/dL predicted PVT with a sensitivity of 65% and a specificity of 71% (AUC:0.767; 95%CI: 0.687 to 0.847; p < 0.001). Lp(a) levels were significantly higher in PVT patients with a history of CVA [42.0 (23.6-53.6) vs. 21.1 (16.1- 36.2) mg/dL, p = 0.012]. Elevated Lp(a) levels may be associated with MPVT. The assessment of plasma Lp(a) levels in patients with prosthetic heart valves may provide additive information regarding the risk of PVT and CVA.

Herein, we present the case of a 23-year-old woman with fulminant myocarditis that led to severe biventricular failure and cardiogenic shock. Despite high-dose inotropes and mechanical support with venoarterial extracorporeal membrane oxygenation plus and Impella CP, the patient's cardiac function did not recover. After upgrading to extracorporeal left ventricular assist device support, persistent right heart failure prevented weaning off venoarterial extracorporeal membrane oxygenation. Chest computed tomography revealed a leftward ascending aorta, prompting left mini-thoracotomy for extracorporeal biventricular assist device surgery, thereby preserving the sternum. Perioperatively, a large aortic thrombus was discovered and removed under deep hypothermic circulatory arrest. An extracorporeal left ventricular assist device was established by draining the left ventricle and perfusing the ascending aorta via the subxiphoid area, whereas the right ventricular assist device was drained from the right subclavian vein into the pulmonary outflow graft through the left second intercostal space. Ultimately, the patient underwent durable left ventricular assist device implantation with concurrent extracorporeal right ventricular assist device support via sternotomy. Preserving the sternum offers several advantages including reduced adhesion and simpler subsequent open procedures. Our experience indicates that extracorporeal biventricular assist device surgery through a left mini-thoracotomy is a viable option for selecting patients, particularly if future sternotomy is anticipated.

Bridging critically ill patients to lung transplantation with veno-venous extracorporeal membrane oxygenation (VV-ECMO) may increase infection risk, yet its impact on post-transplant outcomes remains unclear. We evaluated the incidence, timing, and risk factors for respiratory and bloodstream infections in patients supported with pre-operative VV-ECMO and assessed one-year survival. We conducted a retrospective cohort study of 293 adult lung transplant recipients at a single center between January 2018 and June 2023. Thirty-seven patients received pre-transplant VV-ECMO, and 256 did not. We compared the incidence and median time to first respiratory and bloodstream infections and estimated one-year survival. Cox proportional hazard models identified independent predictors of infection. VV-ECMO patients were younger (median 53.0 vs 63.0 years) and more often underwent bilateral transplantation for acute respiratory distress syndrome. Respiratory infections occurred in 64.9% of the VV-ECMO group versus 56.6% of controls (p = 0.38), with a shorter median time to first respiratory infection (8 vs 63 days). Bacterial bloodstream infections were more frequent after VV-ECMO (18.9% vs 6.3%, p = 0.016) and occurred earlier (99 vs 162 days). In multivariate analysis, VV-ECMO independently predicted bloodstream infection (HR 2.36, 95% CI 1.00-5.53; p = 0.049) but not a respiratory infection. One-year survival was equivalent (81.1% vs 89.8%; p = 0.16). Pre-transplant VV-ECMO is associated with earlier and increased bloodstream infections but does not compromise one-year survival, supporting its continued use as a bridge to lung transplantation.

The relationship between the physical activity status of patients with left ventricular assist devices (LVAD) and their quality of life (QOL) remains unclear. The aim of this study was to determine the association between physical activity status and QOL and to identify the factors influencing walking activity time in LVAD patients. Thirty outpatients with LVAD were included. Physical activity was measured using a triaxial accelerometer. QOL was assessed using the Kansas City Cardiomyopathy Questionnaire (KCCQ). Multiple regression analysis was used to examine the relationship between QOL and activity duration. Physical activity measurement revealed that sedentary behavior of 1.5 metabolic equivalents or less accounted for 72.6% of total activity time. The KCCQ was positively correlated with walking activity time (r = 0.60, p = 0.0005), but not with daily activity time (r = 0.12, p = 0.55). Regression analysis revealed that regular employment (p = 0.0013), low depression score (p = 0.0005), low C-reactive protein level (p = 0.016), and high peak oxygen uptake (p = 0.019) was associated with increased walking activity time. LVAD patients had low physical activity, and walking activity time was significantly associated with their QOL. Comprehensive management may play an important role in improving the QOL in LVAD patients.

Danon disease is a rare inherited disorder, and its prognosis is significantly impacted by cardiac complications. Because of the severe shortage of donors, a ventricular assist device (VAD) is necessary as a bridge to heart transplantation. However, reports on VAD implantation for cardiomyopathy in Danon disease patients are limited. Herein, we report a successful pediatric case with nearly 800-day of biventricular assistance as a bridge to heart transplantation. A 12-year-old girl with severe heart failure due to hypertrophic cardiomyopathy associated with Danon disease underwent left implantation of a Heartware VAD (Heartware Inc., Miami Lakes, FL, USA). Owing to severe right ventricular failure, she was unable to be weaned off the cardiopulmonary bypass, and a right VAD implantation was undertaken using a Gyro pump (Kyosera, Kyoto, Japan). However, the right ventricular function did not recover postoperatively, and she subsequently underwent right implantation of a Heartware VAD on postoperative day 34. Despite several VAD-related complications, including aortic and pulmonary valve insufficiency and a driveline infection requiring hospitalization, the patient was able to attend junior high school during the waiting period for a heart transplantation. After a total waiting period of 882 days, including 791 days of biventricular Heartware VAD assistance, the patient underwent a heart transplantation.

Background: Lung transplantation improves survival in advanced lung disease, but calculated Panel Reactive Antibody (cPRA) positive patients are at higher risk for adverse outcomes. It is unclear if sensitization poses additional risks in patients bridged to transplantation with venovenous extracorporeal membrane oxygenation (VV-ECMO). This study compares outcomes between cPRA-positive and -negative patients bridged with VV-ECMO.

Methods: Among 411 transplant recipients from an institutional lung transplantation database (January 2018-March 2025), 52 patients were bridged with VV-ECMO. Of these, 14 were cPRA-positive and 38 were cPRA-negative. Univariate and multivariate analyses evaluated early post-transplant complications and survival outcomes in cPRA-positive and -negative groups.

Results: Rates of post-transplant complications such as primary graft dysfunction (PGD) in any grade (85.7% cPRA-positive vs. 76.4% cPRA-negative, p = 0.48), PGD grade 3 (35.7% vs. 50.0%, p = 0.53), acute kidney injury (AKI) (64.3% vs. 68.4%, p = 1.00), dialysis requirement (21.4% vs. 34.2%, p = 0.51), deep vein thrombosis (DVT) (71.4% vs. 55.3%, p = 0.35), and pulmonary embolism (PE) (7.1% vs. 18.4%, p = 0.42) were similar. 1-year survival rate (85.1% vs. 82.9%) and overall survival (p = 0.81) were not significantly different.

Conclusions: Post-transplant outcomes and survival were similar between cPRA-positive and -negative groups, suggesting that PRA status in VV-ECMO bridged lung transplant recipients is not associated with worse outcomes. VV-ECMO may remain a viable bridge to lung transplantation, even in sensitized patients.

Endovascular repair (EVAR) for abdominal aortic aneurysm and iliac aneurysm is a safe and valid treatment. However, it is associated with some different complications that may require reinterventions. Among these complications, abdominal endograft proximal collapse is an infrequent event. We report a case of acute type A aortic dissection and abdominal endograft proximal collapse in a patient previously treated with EVAR.

Neutrophil extracellular traps (NETs) were detected in blood samples and in cellular deposits of oxygenator membranes during extracorporeal membrane oxygenation (ECMO) therapy and may be responsible for thrombogenesis. The aim was to evaluate the effect of the base material of gas fiber (GF, polymethylpentene) and heat exchange (HE) membranes and different antithrombogenic coatings on isolated granulocytes from healthy volunteers under static culture conditions. Contact of granulocytes with membranes from different ECMO oxygenators (with different surface coatings) and uncoated-GFs allowed detection of adherent cells and NETotic nuclear structures (normal, swollen, ruptured) using nuclear staining. Flow cytometry was used to identify cell activation (CD11b/CD62L, oxidative burst) of non-adherent cells. Uncoated-GFs were used as a reference. Within 3 h, granulocytes adhered to the same extent on all surfaces. In contrast, the ratio of normal to NETotic cells was significantly higher for uncoated-GFs (56-83%) compared to all coated GFs (34-72%) (p < 0.001) with no difference between the coatings. After material contact, non-adherent cells remained vital with unchanged oxidative burst function and the proportion of activated cells remained low. The expression of activation markers was independent of the origin of the GF material. In conclusion, the polymethylpentene surfaces of the GFs already induce NET formation. Antithrombogenic coatings can already reduce the proportion of NETotic nuclei. However, it cannot be ruled out that NET formation can induce thrombotic events. Therefore, new surfaces or coatings are required for future ECMO systems and long-term implantable artificial lungs.