Anti-hypertensive drugs and left ventricular hypertrophy: a clinical update

In this review, we present some different and special conditions that are generally being treated with anticoagulants such as cerebral vein thrombosis (CVT), mesenteric vein thrombosis (MVT), Budd–Chiari syndrome (BCS), and Pulmonary Hypertension (PH) despite the lack of controlled clinical trials. While either low molecular weight heparins (LMWHs) or unfractioned heparin (UFH) are used in the acute phase of the first three conditions, the potential chronic use of warfarin in PH is controversial. What is not completely known in the management of CVT, MTV, and BCS is whether (a) LMWHs are similar to UFH in terms of efficacy and safety, and (b) a fibrinolytic drug could be employed in the acute phase. The timing at which warfarin should be started, and the duration of its employment are two additional crucial points that deserve to be examined. In the course of PH, the role of warfarin is controversial, but it could be employed after a careful balance of the hemorrhagic and thromboembolic risk. In conclusion, we tried to simplify the approach to this sometimes problematic task considering the available literature with the aim of providing some practical skills to be used by physicians in their daily clinical practice. Since it is improbable that in the future controlled clinical trials will be designed to find the optimal anti-thrombotic management of these conditions, we believe that a physician should be aware of the lack of solid data in the field but at the same time should always exert clinical judgment when considering an aggressive anticoagulant approach. The duration of oral anticoagulant treatment is left to the clinical judgment of the balance between the hemorrhagic and thrombotic risks in any single patient.     

Linear regression models and k-means clustering for statistical analysis of fNIRS data

We propose a new algorithm, based on a linear regression model, to statistically estimate the hemodynamic activations in fNIRS data sets. The main concern guiding the algorithm development was the minimization of assumptions and approximations made on the data set for the application of statistical tests. Further, we propose a K-means method to cluster fNIRS data (i.e. channels) as activated or not activated. The methods were validated both on simulated and in vivo fNIRS data. A time domain (TD) fNIRS technique was preferred because of its high performances in discriminating cortical activation and superficial physiological changes. However, the proposed method is also applicable to continuous wave or frequency domain fNIRS data sets.OCIS codes: (000.5490) Probability theory, stochastic processes, and statistics; (170.2655) Functional monitoring and imaging; (170.6920) Time-resolved imaging; (170.1470) Blood or tissue constituent monitoring     

Chemotherapy-Associated Liver Injuries: Unmet Needs and New Insights for Surgical Oncologists

Annals of Surgical Oncology -     

Dynamic clustering of hazard functions: an application to disease progression in chronic heart failure

We analyse data collected from the administrative datawarehouse of an Italian regional district (Lombardia) concerning patients affected by Chronic Heart Failure. The longitudinal data gathering for each patient hospital readmissions in time, as well as patient-specific covariates, is studied as a realization of non homogeneous Poisson process. Since the aim behind this study is to identify groups of patients behaving similarly in terms of disease progression and then healthcare consumption, we conjectured the time segments between two consecutive hospitalizations to be Weibull distributed in each hidden cluster. Adding a frailty term to take into account the within subjects unknown variability, the corresponding patient-specific hazard functions are reconstructed. Therefore, the comprehensive distribution for each time to event variable is modelled as a Weibull Mixture. We are then able to easily interpret the related hidden groups as healthy, sick, and terminally ill subjects.     

Diagnostic compatibility of structural and haemodynamic parameters in open‐angle glaucoma patients

Purpose: Current evidence indicates that alteration in ocular blood flow may be relevant in open‐angle glaucoma (OAG) patients independent of intraocular pressure (IOP). Presently, the lack of an adequate methodology capable of assessing all vascular beds limits the clinical role of blood flow parameters in glaucoma management. We aimed to compare differences in retinal nerve fibre layer (RNFL) thickness and retrobulbar haemodynamics between OAG patients and healthy age‐matched control subjects. Methods: Sixty eyes of 30 OAG patients and 30 healthy age‐matched controls were enrolled into the prospective, randomized study. Retinal nerve fibre layer thickness was analysed by scanning laser polarimetry (SLP). Standard SLP parameters were determined, including: average temporal, superior, nasal, inferior thickness (TSNIT); superior and inferior averages; TSNIT standard deviation (TSNIT‐SD), and nerve fibre indicator (NFI). Retrobulbar haemodynamics were assessed using colour Doppler imaging (CDI). Peak systolic velocity (PSV), end‐diastolic velocity (EDV), pulsatility index (PI) and resistivity index (RI) in the ophthalmic artery (OA), central retinal artery (CRA) and short posterior ciliary artery (SPCA) were evaluated. Results: The RNFL in OAG patients was statistically significantly thinner compared with that in age‐matched controls: the NFI was 24.9 ± 10.24 in OAG patients and 16.13 ± 7.95 in healthy controls (p < 0.05). Statistically significant differences were observed: CRA PSV was 20.54 ± 7.84 cm/second in OAG subjects and 16.5 ± 6.19 cm/second in healthy controls (p = 0.0038); OA EDV was 8.99 ± 4.71 cm/second in OAG subjects and 5.93 ± 3.23 cm/second in healthy controls (p = 0.0048). Correlation analysis of NFI was in positive association with CRA EDV (r = 0.395; p < 0.05) and CRA PI (r = 0.403; p < 0.05) in OAG subjects, but no statistically significant association was seen in healthy controls. Conclusions: Statistically significant thinning of the RNFL in association with reduced retrobulbar blood flow velocities was observed in OAG patients. Combining ocular structural alterations with ocular circulation assessment may increase our ability to elucidate potential IOP‐independent glaucomatous risk factors.     

Antiangiogenic strategies in medulloblastoma: reality or mystery

Medulloblastoma is the most common malignant brain tumor of childhood. Surgery, radiation therapy, and chemotherapy successfully cure many patients, but survivors can suffer long-term toxicities affecting their neurocognitive and growth potential; furthermore, there is no curative therapy in up to 30% of cases, mainly because of our incomplete understanding of many of the underlying molecular and cellular processes. Angiogenesis is a hallmark of the progression of medulloblastoma and, over the last years, investigators have sought to develop effective and less toxic antiangiogenic strategies, including the inhibition or destruction of abnormal blood vessels using either antiangiogenic or vascular disrupting agents. However, the results are conflicting principally because of the complex biology of tumor vasculature and the irregular geometry of the vascular system in real space. In addition, current targets of antiangiogenic therapy, such as vascular endothelial growth factor (VEGF), are thought to be critical for both physiologic and pathologic angiogenesis, and clinical side effects of anti-VEGF therapy are beginning to emerge. We here review the state-of-the-art concerning antiangiogenic targets for medulloblastoma treatment, and discuss the complexity of the vascular system that intrinsically limits the efficacy of current strategies.     

Incidence and precipitating factors of delirium after coronary artery bypass grafting

OBJECTIVE: To analyze large contemporary patient population, undergoing on-pump coronary artery bypass grafting at our institution, and identify the prevalence and precipitating factors of delirium development. DESIGN: Baseline demographics, operative data and postoperative outcomes of 1367 consecutive patients were recorded prospectively and analysed using multivariate logistic regression analysis, to determine independent predictors of postoperative delirium development. RESULTS: Delirium was detected in 42 (3.07%) patients. Eight factors: age more than 65 years, peripheral vascular disease, Euroscore>/=5, preoperative IABP support, postoperative blood product usage and postoperative low cardiac output syndrome were independently predicting delirium development after coronary artery bypass procedures. Postoperative delirium was associated with significantly higher mortality rate (16.6% vs. 3.9%, p=0.013), prolonged mechanical ventilation time (9.2+/-3.1 vs. 5.05+/-7.6, p=0.04) and increased length of intensive care unit stay (6.8+/-4.9 vs. 2.0+/-2.7 days, p=0.001). CONCLUSIONS: Delirium is a dangerous complication, prolonging intensive care unit stay and postoperative mortality. Factors associated with delirium development are advanced age, peripheral vascular disease, diminished cardiac function and blood product usage.