Recanalization of the Native Artery in Patients with Bypass Failure

Our objective was to evaluate the possible role of endovascular recanalization of occluded native artery after a failed bypass graft in the case of either acute or chronic limb-threatening ischemia otherwise leading to amputation. In a single-center retrospective clinical analysis, from January 2004 to March 2007 we collected 31 consecutive high-surgical-risk patients (32 limbs) with critical limb ischemia following late ([30 days after surgery) failure of open surgery bypass graft reconstruction. All patients deemed unfit for surgery underwent tentative endovascular recanalization of the native occluded arterial tract. The mean follow-up period was 24 (range, 6–42) months. Technical success was achieved in 30 (93.7%) of 32 limbs. The cumulative primary assisted patency calculated by Kaplan–Meyer analysis was 92% and 88%, respectively, at 12 and 24 months. The limb salvage rate approached 90% at 30 months. In conclusion, our experience shows the feasibility of occluded native artery endovascular recanalization after a failed bypass graft, with optimal results in terms of midterm arterial patency and limb salvage. Our opinion is that successful recanalization of the arterial tract previously considered unsuitable for endovascular approach is allowed by improved competency and experience of vascular specialists, as well as the advances made in catheter and guidewire technology. This group of patients would previously have been relegated to repeat bypass grafts, with their inherently inferior patency and recognized added technical demands. We recognize previous surgical native artery disconnection and lack of pedal runoff to be the main cause of technical failure. Keywords Native artery Bypass failure Endovascular recanalizatio

Distribution and origin of natural gas leakage in the Colorado Basin, offshore Argentina Margin, South America : seismic interpretation and 3D basin modelling

The detailed analysis of a dense 2D seismic reflection dataset and data from 8 exploration wells, allowed us to identify, map out and characterize possible indications of past and present-day hydrocarbon leakage (i.e. gas chimneys, gas pockets, and seafloor mounds and pockmarks) on the continental shelf and slope of the Colorado Basin, offshore Argentina, where Permian, Jurassic and Early Cretaceous source rocks are potentially present and may be currently mature. Identified gas leakage features, developed both in the syn-rift and post-rift successions, were also analysed in relation to the structural the stratigraphic elements of the basin. A family of seabed pockmarks, located close to an array of submarine channels, was identified on the distal slope of the basin. These pockmarks are overlying a series of sub-vertical to vertical seismic chimneys in the subsurface. A calibrated basin-wide 3D petroleum system model comprising generation and migration of hydrocarbons was carried out and compared with the observations from the seismic analysis. Preliminary results from this model indicate that although synrift and early Cretaceous source rock (SR) intervals may be depleted in the central areas of the basin, an active kitchen from the Aptian SR may be present below the slope areas. Hydrocarbon migration pathways predicted by the 3D model (Hybrid method) coincide with the interpreted seismic chimneys underlying the observed seabed slope pockmarks. Hence, our results indicate that thermogenic gas may be currently generated in the distal slope of the basin from mature early post-rift source rocks within the Early Cretaceous (Aptian) sequences and migrates vertically, due to seal failure, through the stratigraphic column. This migrating thermogenic gas is feeding the seafloor pockmarks identified in the distal slope of the basin, although up-dip lateral migration along stratigraphic layers to the more proximal slope areas cannot be ruled out. The present work represents the first published study integrating detailed seismic analysis and 3D basin modelling linking observed gas-leakage indicators and associated seepage pathways, to their relative abundance, distribution and feeding systems offshore Argentina's continental margin

Triatomineos do Rio Grande do Sul

Triatomineos do Rio Grande do Su

Pesquisa de triatomíneos nos municípios de Erechim e Getulio Vargas. Resultados de outras investigações

Pesquisa de triatomíneos nos municípios de Erechim e Getulio Vargas. Resultados de outras investigaçõe

Alguns aspectos da ancilostomose no Rio Grande do Sul

Alguns aspectos da ancilostomose no Rio Grande do Su

Carotid artery stenting: a single-centre experience with up to 8 years' follow-up

Carotid artery stenting (CAS) may be an alternative to surgical endoarterectomy not only in high-risk patients. We report results in the endovascular treatment of carotid artery disease with up to 8 years' follow-up. In this retrospective study, we analysed data from 853 consecutive patients (946 arteries) treated for carotid artery stenosis between April 1999 and March 2007; 491 (52%) arteries were symptomatic and 455(48%) were asymptomatic. Preprocedural evaluation of the patients was performed with echo Doppler, magnetic resonance angiography (MRA) or computed tomographic angiography (CTA) and a neurological examination. A cerebral protection device was used in 879 (92.9%) procedures. Anti-platelet therapy was administered before and after the procedure. All patients were included in a follow-up of up to 8 years. Technical success was achieved in 943 (99.6%) lesions. At 30 days, there was a 0.21% (n = 2) death rate, a 0.42% major stroke rate, a 1.69% minor stroke/transient ischaemic attack (TIA) rate and a combined 2.32% TIA/stroke and death rate. During follow-up, echo Doppler evidenced restenosis in 39 (4.85%) cases; of these, only five, presenting restenosis > 80%, were treated with an endovascular reintervention. At the long-term follow-up, two strokes (0.23%) were reported, which both occurred within the first 2 years. In our experience, carotid artery stenting seems to be a safe and effective treatment, providing satisfactory long-term clinical results

Distribuição geográfica do Panstrongylus megistus no Rio Grande do Sul

Distribuição geográfica do Panstrongylus megistus noRio Grande do Su

Atual distribuição geográfica dos triatomíneos e seus índices de infecção no Rio Grande do Sul

Atual distribuição geográfica dos triatomíneos e seus índices de infecção no Rio Grande do Su

Nona contribuição para o reconhecimento microscópico dos resíduos fecais de origem alimentar

Nona contribuição para o reconhecimento microscópico dos resíduos fecais de origem alimenta