"In Vitro" Evaluation of Energy-Based Sealing of Graft Side Branches in Bypass Surgery.

INTRODUCTION: Our objective was to compare the in vitro efficacy of electrothermal bipolar [EB] vessel sealing and ultrasonic harmonic scalpel [HS] versus mechanical interruption, with conventional ties or surgical clips (SC), in sealing saphenous vein (SV) collaterals, during its eventual preparation for bypass surgery. METHODS: Experimental in vitro study on 30 segments of SV. Each fragment included two collaterals at least 2 mm in diameter. One of them was sealed by ligation with 3/0 silk ties (control) and the other one with EB (n = 10), HS (n = 10) or medium-6 mm SC (n = 10). After incorporation in a closed circuit with pulsatile flow, the pressure was progressively increased until causing rupture. Collateral diameter, burst pressure, leak point, and histological study were recorded. RESULTS: Burst pressure was higher for SC (1320.20 ± 373.847 mmHg) as compared with EB (942.2 ± 344.9 mmHg, p = 0.065), and especially with HS (637.00 ± 320.61 mmHg, p = 0.0001). No statistically significant difference between EB and HS was found, and bursting always happened at supraphysiological pressures. The leak point for HS was always detected in the sealing zone (10/10), while for EB and SC, it occurred in the sealing zone only in 6/10(60%) and 4/10(40%), respectively (p = 0.015). CONCLUSIONS: Energy delivery devices showed similar efficacy and safety in sealing of SV side branches. Although bursting pressure was lower than with tie ligature or SC, non-inferiority efficacy was shown at the range of physiological pressures in both, EB and HS. Due to their speed and easy handling, they may be useful in the preparation of the venous graft during revascularization surgery. However, remaining questions about healing process, potential spread of tissue damage and sealing durability, will require further analysis.

Thrombospondins in human aortic aneurysms.

Thrombospondins are a family of matricellular proteins with a multimeric structure that is known to be involved in several biological and pathological processes. Their relationship with vascular disorders has raised special interest recently. Aortic aneurysms are related to the impairment of vascular remodeling, in which extracellular matrix proteins seem to play an important role. Thus, research in thrombospondins, and their potential role in aneurysm development is progressively gaining importance. Nevertheless, studies showing thrombospondin dysregulation in human samples are still scarce. Although studies performed in vitro and in vivo models are essential to understand the molecular mechanisms and pathways underlying the disorder, descriptive studies in human samples are also necessary to ascertain their real value as biomarkers and/or novel therapeutic targets. The present article reviews the latest findings regarding the role of thrombospondins in aortic aneurysm development, paying particular attention to the studies performed in human samples.

Genetic alterations of IDH1 and Vegf in brain tumors.

BACKGROUND: This study evaluates the presence of R132H mutation in isocitrate dehydrogenase (IDH1) gene and the vascular endothelial growth factor (VEGF) +936 C/T polymorphism in brain tumors. The impact of these genetic alterations on overall survival (OS) and progression free survival (PFS) was evaluated. METHODS: A cohort of 80 patients surgically treated at Hospital Clínico San Carlos, Madrid, between March 2004 and November 2012, was analyzed. Tumors were distributed in 73 primary brain tumors (gliomas, meningiomas, hemangiopericytomas and hemangioblastomas) and seven secondary tumors evolved from a low grade glioma, thus providing a mixed sample. RESULTS: IDH1R132H gene mutation was found in 12 patients (15%) and appears more frequently in secondary tumors (5 (71.4%) whereas in 7 (9.7%) primary tumors (p < .001)). The mutation is related to WHO grade II in primary tumors and a supratentorial location in secondary tumors. The OS analysis for IDH1 showed a tendency towards a better prognosis of the tumors containing the mutation (p = .059).The IDH1R132H mutation confers a better PFS (p = .025) on primary tumors. The T allele of VEFG +936 C/T polymorphism was found in 16 patients (20%). No relation was found between this polymorphism and primary or secondary tumor, neither with OS or PFS. CONCLUSIONS: IDH1R132H gene mutation is exclusive in supratentorial tumors and more frequent in secondary ones, with a greater survival trend and better PFS in patients who carry it. The T allele of VEGF +936 C/T polymorphism is more common in primary tumors, although there is no statistical relation with survival.