CASE PRESENTATION: We present a successful aortic valve replacement with cardiopulmonary bypass in a 48 years old lady with antiphospholipid syndrome, who has severe aortic regurgitation as a result of Libman-sacks endocarditis. Antiphospholipid antibodies were positive and the clinical data showed both negative cultures and infective parameters. Surgically resected vegetations revealed sterile fibrinous and verrucous vegetations on aortic valve. Valve replacement and the course of cardiopulmonary bypass was uneventful, and the patient was discharged well.
CONCLUSIONS: Classically Libman-Sacks endocarditis is often and more commonly associated with autoimmune diseases such as systemic lupus erythematosus, although it can occur in both primary and secondary antiphospholipid syndrome. It is not a common entity, and it is a frequent underestimated disease as most clinicians do not routinely screen for valvular lesion in patients with antiphospholipid syndrome unless they are symptomatic. However, due to its high prevalence of cardiac involvement, clinicians should have a high index of suspicion in the attempt to minimize cardiovascular and haemodynamic complications. Valve surgery in patients with antiphospholipid syndrome carries considerable early and late morbidity and mortality, usually caused by thromboembolic and bleeding events. The perioperative anticoagulation management and haemostatic aspect of antiphospholipid syndrome present an exceptional challenges to clinicians, surgeons, anaesthetists and laboratory personnel.
METHODS: hUC-MSCs were labelled with GFP-Luc2 protein, followed by characterisation with flow cytometry. Upon intravenous infusion of transduced hUC-MSCs into the healthy BALB/c mice, the cells were dynamically monitored through the bioluminescent imaging (BLI) approach.
RESULTS: Transduction of hUC-MSCs with GFP-Luc2 not only preserved the characteristics of MSCs, but also allowed live monitoring of transduced cells in the mice model. Upon systemic administration, BLI showed that transduced hUC-MSCs first localised predominantly in the lungs of healthy BALB/c mice and mainly remained in the lungs for up to 3 days before eventually cleared from the body. At terminal sacrifice, plasma chemistry biomarkers remained unchanged except for C-peptide levels, which were significantly reduced in the hUC-MSCs group. Histopathological findings further revealed that hUC-MSCs infusion did not cause any adverse effects and toxicity to lung, liver and heart tissues.
CONCLUSIONS: Collectively, systemically administrated hUC-MSCs was safe and demonstrated dynamic homing capacity before eventually disappearing from the body.