A Peculiar Case of a Floating Angio-Seal.

PURPOSE: To show a complication of the use of an Angio-Seal™ closure device. CASE: We present a patient with a systolic murmur in his femoral artery after PCI. The murmur was caused by a dislocated Angio-Seal™, a vascular closure device. This was diagnosed by Doppler Ultrasound. The device was surgically removed. CONCLUSION: Vascular complications, such as lower limb ischemia, requiring surgical intervention tend to be higher after use of a vascular closure device. We advise routine physical examination of the puncture site after percutaneous closure with a vascular closure device, such as an Angio-Seal™. The removal of the device can be performed via an open or endoscopic approach, based on available experience.

Sinusoidal obstruction syndrome (SOS): A light and electron microscopy study in human liver.

AIMS: Oxaliplatin is an important chemotherapeutic agent, used in the treatment of hepatic colorectal metastases, and known to induce the sinusoidal obstruction syndrome (SOS). Pathophysiological knowledge concerning SOS is based on a rat model. Therefore, the aim was to perform a comprehensive study of the features of human SOS, using both light microscopy (LM) and electron microscopy (EM). METHODS AND RESULTS: Included were all patients of whom wedge liver biopsies were collected during a partial hepatectomy for colorectal liver metastases, in a 4-year period. The wedge biopsy were perfusion fixated and processed for LM and EM. The SOS lesions were selected by LM and details were studied using EM. Material was available of 30 patients, of whom 28 patients received neo-adjuvant oxaliplatin. Eighteen (64%) of the 28 patients showed SOS lesions, based on microscopy. The lesions consisted of sinusoidal endothelial cell detachment from the space of Disse on EM. In the enlarged space of Disse a variable amount of erythrocytes were located. CONCLUSION: Sinusoidal endothelial cell detachment was present in human SOS, accompanied by enlargement of the space of Disse and erythrocytes in this area. These findings, originally described in a rat model, were now for the first time confirmed in human livers under clinically relevant settings.

Adipose tissue-derived stromal cells acquire endothelial-like features upon reprogramming with SOX18.

Adipose tissue-derived stromal cells (ASC) form a rich source of autologous cells for use in regenerative medicine. In vitro induction of an endothelial phenotype may improve performance of ASCs in cardiovascular repair. Here, we report on an in vitro strategy using direct reprogramming of ASCs by means of ectopic expression of the endothelial-specific transcription factor SRY (sex determining region Y)-box18 (SOX18). SOX18 induces ASCs to express a set of genes involved in vascular patterning: MMP7, KDR, EFNB2, SEMA3G and CXCR4. Accordingly, SOX18 transduced ASCs reorganize under conditions of shear stress, display VEGF-induced chemotaxis and form tubular structures in 3D matrices in an MMP7-dependent manner. These in vitro findings provide insight into molecular and cellular processes downstream of SOX18 and show that reprogramming using SOX18 is sufficient to induce several endothelial-like features in ASCs.

Glutathione S-transferase M1-null genotype as risk factor for SOS in oxaliplatin-treated patients with metastatic colorectal cancer.

BACKGROUND: Oxaliplatin is used as a neo-adjuvant therapy in hepatic colorectal carcinoma metastasis. This treatment has significant side effects, as oxaliplatin is toxic to the sinusoidal endothelial cells and can induce sinusoidal obstruction syndrome (SOS), which is related to decreased overall survival. Glutathione has an important role in the defence system, catalysed by glutathione S-transferase (GST), including two non-enzyme producing polymorphisms (GSTM1-null and GSTT1-null). We hypothesise that patients with a non-enzyme producing polymorphism have a higher risk of developing toxic injury owing to oxaliplatin. METHODS: In the nontumour-bearing liver, the presence of SOS was studied histopathologically. The genotype was determined by a semi-nested PCR. RESULTS: Thirty-two of the 55 (58%) patients showed SOS lesions, consisting of 27% mild, 22% moderate and 9% severe lesions. The GSTM1-null genotype was present in 25 of the 55 (46%). Multivariate analysis showed that the GSTM1-null genotype significantly correlated with the presence of (moderate-severe) SOS (P=0.026). CONCLUSION: The GSTM1-null genotype is an independent risk factor for SOS. This finding allows us, in association with other risk factors, to conceive a potential risk profile predicting whether the patient is at risk of developing SOS, before starting oxaliplatin, and subsequently might result in adjustment of treatment.

Development of a composite endpoint for randomized controlled trials in liver surgery.

BACKGROUND: The feasibility of randomized controlled trials (RCTs) in liver surgery using a single-component clinical endpoint is low as such endpoints require large sample sizes owing to their low incidence. A liver surgery-specific composite endpoint (CEP) could solve this problem. The aim of this study was to develop a liver surgery-specific CEP with well-defined components. METHODS: Components of a liver surgery-specific CEP were selected based on a systematic literature search and consensus among 28 international hepatopancreatobiliary (HPB) surgeons. As an example, two prospective cohorts of patients who had undergone liver surgery in high-volume HPB centres were used to assess the event rate and effect of implementing a liver surgery-specific CEP. RESULTS: Components selected for the liver surgery-specific CEP were ascites, postresectional liver failure, bile leakage, intra-abdominal haemorrhage, intra-abdominal abscess and operative mortality, all with a Clavien-Dindo grade of at least 3 and occurring within 90 days after initial surgery. The incidence of this liver surgery-specific CEP was 19.2 per cent in one cohort and 10.7 per cent in the other. These rates led to an approximately twofold reduction in the theoretical sample size required for an adequately powered RCT in liver surgery using the CEP as primary endpoint. CONCLUSION: The proposed liver surgery-specific CEP consists of ascites, postresectional liver failure, bile leakage, intra-abdominal haemorrhage, intra-abdominal abscess and operative mortality. It has a considerably higher event rate than any of its components. Its use as the primary endpoint will increase the feasibility and comparability of RCTs in liver surgery.

Feasibility of randomized controlled trials in liver surgery using surgery-related mortality or morbidity as endpoint.

BACKGROUND: There is a shortage of randomized controlled trials (RCTs) on which to base guidelines in liver surgery. The feasibility of conducting an adequately powered RCT in liver surgery using the dichotomous endpoints surgery-related mortality or morbidity was examined. METHODS: Articles published between January 2002 and November 2007 with mortality or morbidity after liver surgery as primary endpoint were retrieved. Sample size calculations for a RCT aiming to show a relative reduction of these endpoints by 33, 50 or 66 per cent were performed. RESULTS: The mean operative mortality rate was 1.0 per cent and the total morbidity rate 28.9 per cent; mean rates of bile leakage and postresectional liver failure were 4.4 and 2.6 per cent respectively. The smallest numbers of patients needed in each arm of a RCT aiming to show a 33 per cent relative reduction were 15 614 for operative mortality, 412 for total morbidity, 3446 for bile leakage and 5924 for postresectional liver failure. CONCLUSION: The feasibility of conducting an adequately powered RCT in liver surgery using outcomes such as mortality or specific complications seems low. Conclusions of underpowered RCTs should be interpreted with caution. A liver surgery-specific composite endpoint may be a useful and clinically relevant solution to pursue.