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1.
Environ Toxicol Chem ; 41(12): 2968-2980, 2022 12.
Article in English | MEDLINE | ID: mdl-36089896

ABSTRACT

Amphibians have been facing global declines over the last decades from direct and indirect effects of anthropogenic activities. A contributor to declines is waterway contamination from agricultural runoffs of pesticides such as neonicotinoids. Beyond direct and indirect effects of the pesticide, few studies have investigated the possible interactions between neonicotinoids and natural environmental stressors across larval development, which could alter the strength and direction of observed neonicotinoid effects. The present study used a fully crossed design to investigate how a concentration of imidacloprid (a neonicotinoid; 10 µg/L) measured in surface waters interacted with low and high population densities (0.33 and 1 tadpole/L, respectively), an important environmental stressor, to influence behavior and development across metamorphosis in wood frogs (Rana sylvatica), known to breed in agricultural landscapes. Behaviors were measured in the absence and presence of predation cues using open-field tests at three distinct developmental stages, up to the metamorph stage. We found that imidacloprid did not interact with population density or independently affect behaviors in the absence of predation cues. However, individuals raised at high density compared with low density were more active at an early developmental stage but less active at metamorphic climax. Furthermore, both density and imidacloprid independently decreased the natural freezing response of tadpoles to predation cues. Finally, we found that distance traveled in the open-field test was weakly repeatable between aquatic stages but not repeatable across metamorphosis, a pattern that was not affected by treatments. The present study provides novel insights on the ecotoxicology of imidacloprid in the presence of a natural stressor, highlighting the importance of including behavioral assays and natural stressors in studies of amphibian ecotoxicology. Environ Toxicol Chem 2022;41:2968-2980. © 2022 SETAC.


Subject(s)
Insecticides , Pesticides , Humans , Animals , Insecticides/toxicity , Population Density , Neonicotinoids/toxicity , Ranidae/physiology , Larva , Pesticides/pharmacology
2.
Nature ; 554(7690): 73-76, 2018 02 01.
Article in English | MEDLINE | ID: mdl-29310123

ABSTRACT

White-dwarf stars are the end product of stellar evolution for most stars in the Universe. Their interiors bear the imprint of fundamental mechanisms that occur during stellar evolution. Moreover, they are important chronometers for dating galactic stellar populations, and their mergers with other white dwarfs now appear to be responsible for producing the type Ia supernovae that are used as standard cosmological candles. However, the internal structure of white-dwarf stars-in particular their oxygen content and the stratification of their cores-is still poorly known, because of remaining uncertainties in the physics involved in stellar modelling codes. Here we report a measurement of the radial chemical stratification (of oxygen, carbon and helium) in the hydrogen-deficient white-dwarf star KIC08626021 (J192904.6+444708), independently of stellar-evolution calculations. We use archival data coupled with asteroseismic sounding techniques to determine the internal constitution of this star. We find that the oxygen content and extent of its core exceed the predictions of existing models of stellar evolution. The central homogeneous core has a mass of 0.45 solar masses, and is composed of about 86 per cent oxygen by mass. These values are respectively 40 per cent and 15 per cent greater than those expected from typical white-dwarf models. These findings challenge present theories of stellar evolution and their constitutive physics, and open up an avenue for calibrating white-dwarf cosmochronology.

3.
J Evol Biol ; 28(11): 1975-85, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26310599

ABSTRACT

Intralocus sexual conflict arises when selection favours alternative fitness optima in males and females. Unresolved conflict can create negative between-sex genetic correlations for fitness, such that high-fitness parents produce high-fitness progeny of their same sex, but low-fitness progeny of the opposite sex. This cost of sexual conflict could be mitigated if high-fitness parents bias sex allocation to produce more offspring of their same sex. Previous studies of the brown anole lizard (Anolis sagrei) show that viability selection on body size is sexually antagonistic, favouring large males and smaller females. However, sexual conflict over body size may be partially mitigated by adaptive sex allocation: large males sire more sons than daughters, whereas small males sire more daughters than sons. We explored the evolutionary implications of these phenomena by assessing the additive genetic (co)variance of fitness within and between sexes in a wild population. We measured two components of fitness: viability of adults over the breeding season, and the number of their progeny that survived to sexual maturity, which includes components of parental reproductive success and offspring viability (RS(V) ). Viability of parents was not correlated with adult viability of their sons or daughters. RS(V) was positively correlated between sires and their offspring, but not between dams and their offspring. Neither component of fitness was significantly heritable, and neither exhibited negative between-sex genetic correlations that would indicate unresolved sexual conflict. Rather, our results are more consistent with predictions regarding adaptive sex allocation in that, as the number of sons produced by a sire increased, the adult viability of his male progeny increased.


Subject(s)
Genetic Fitness/physiology , Lizards/genetics , Lizards/physiology , Sexual Behavior, Animal/physiology , Animals , Female , Genotype , Male , Microsatellite Repeats , Sex Ratio
4.
Science ; 340(6132): 549, 2013 May 03.
Article in English | MEDLINE | ID: mdl-23641093

ABSTRACT

Byers and Dunn (Reports, 9 November 2012, p. 802) claimed that predation on offspring reduced the potential for sexual selection in pronghorn. We argue that the potential for sexual selection is not affected by random offspring mortality when relative reproductive success is considered and increases when measured with the opportunity for selection, a metric that describes the potential for selection.


Subject(s)
Antelopes/physiology , Mating Preference, Animal , Predatory Behavior , Sexual Behavior, Animal , Animals , Female , Male
5.
J Evol Biol ; 26(4): 766-74, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23437956

ABSTRACT

Heterogeneous forces of selection associated with fluctuating environments are recognized as important factors involved in the maintenance of inter-individual phenotypic variance within populations. Consistent behavioural differences over time and across situations (e.g. personality) are increasingly cited as examples of individual variation observed within populations. However, the suggestion that heterogeneous selective pressures target different animal personalities remains largely untested in the wild. In this 5-year study, we investigated the dynamics of viability selection on a personality trait, exploration, in a population of eastern chipmunks (Tamias striatus) experiencing substantial seasonal variations in weather conditions and food availability associated with masting trees. Contrary to our expectations, we found no evidence of fluctuating selection on exploration. Instead, we found strong disruptive viability selection on adult exploration behaviour, independent of seasonal variations. Individuals with either low or high exploration scores were almost twice as likely to survive over a 6-month period compared with individuals with intermediate scores. We found no evidence of viability selection on juvenile exploration. Our results highlight that disruptive selection might play an important role in the maintenance of phenotypic variance of wild populations through its effect on different personality types across temporally varying environmental conditions.


Subject(s)
Behavior, Animal/physiology , Exploratory Behavior/physiology , Sciuridae/physiology , Selection, Genetic , Animals , Female , Male , Models, Biological , Personality , Phenotype , Seasons , Survival Analysis , Time Factors
6.
J Cardiovasc Surg (Torino) ; 53(3): 345-53, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22695267

ABSTRACT

AIM: Extend thoraco-abdominal aortic aneurysms (TAAA) involving arch vessels and the visceral arteries remains a challenging operation when affecting high risk patients (HRP). Recently, hybrid surgery has gained popularity for HRP. The conventional surgical repair is the gold standard for low risk patients with previous mortality from 6% to 15% in thoracic aneurysms up to 30% in thoracic type B dissections. The risk of paraplegia is 3% to 15%. Without repair the outcome is poor with only 35% of patient's survival at two years after diagnosis. The total endovascular technique is not widespread used because of its very time-consuming, needs training, and procedure planning with high radiation exposure. Only few centers in the world perform it. In order to reduce the morbidity a novel approach is proposed, with an aortic debranching from the ascending aorta. METHODS: Nine patients (two females) aged between 53 and 81 years, with high risk factors for surgery, were offered this hybrid technique from March 2004 to July 2009. Eight patients presented with a TAAA and one type a B chronic dissection. A staged hybrid operation started by a debranching of the aorta from a median sternotomy to supra-aortic vessels and visceral arteries, followed by the second stage one-two weeks later, with an extended stent grafting. This attitude avoids CPB and aortic cross clamping. The surgical approach is a median sternotomy combined to mid upper laparotomy associated to pericardial and diaphragm division. It is well tolerated even in elderly patients and allows easy access to celiac axis (CA), superior mesenteric artery (SMA), right renal artery (RRA). Access to the left renal artery is more difficult and may be benefit from a combinated stent grafting and bypass according to the VORTEC technique described by Lachat M, or an extra-anatomic bypass. Rerouting the visceral arteries is done from the ascending aorta with a partial clamping on an undiseased implantation site, offering à good anterograde high flow. Combined bypass to supraaortic vessels is associated when needed. RESULTS: There was no intraoperative mortality. One patient died during 30D period from cardiac failure and another on the early follow up from a pancreatic fistula. The complications: one stroke (11.1%); one cardiac failure (11.1%); one renal failure (11.1%), one pancreatic fistula (11.1%), one non-infected retrostrenal collection (11.1%). No paraplegia, limb ischemia or aortic fistula were detected. No stent-graft related complication was retrieved, the bypass patency was 77.7 at four-year survival. CONCLUSION: Our early and mid term results are promising and similarly to other series. This new approach for rerouting the supraaortic and visceral arteries before stent grafting in extended TAAA, lowers the surgical injury and is particularly designed for HRP who cannot benefit from conventional surgery under CPB. Larger series and longer follow-up are needed.


Subject(s)
Aorta, Thoracic/surgery , Aortic Aneurysm, Thoracic/surgery , Aortic Dissection/surgery , Blood Vessel Prosthesis , Vascular Surgical Procedures/methods , Aged , Aged, 80 and over , Aortic Dissection/diagnosis , Aortic Aneurysm, Thoracic/diagnosis , Chronic Disease , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prosthesis Design , Retrospective Studies , Risk Factors , Treatment Outcome
7.
Int J Hyg Environ Health ; 214(6): 478-84, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21917514

ABSTRACT

For accompanying actions to pollution crisis management of recreational waters, rapid methods providing a quantified faecal indicator which can be completed in less than half a day, are currently needed. Two sensitive rRNA-targeted Reverse Transcription-quantitative PCR (RT-qPCR) methods were developed for quantifying Escherichia coli and Enterococcus spp. cells in marine bathing waters. Threshold cycle (Ct) values were found to be linear with a target quantity over a 4log dynamic range (from 10(5) to 100 cell equivalents per 100ml). In order to confirm the scope of application of such alternative methods, 80 and 85 seawater samples from the Atlantic Ocean and Mediterranean sea were analysed by both RT-qPCR and ISO culture-based methods for E. coli and Enterococcus spp. enumerations. This study demonstrates that by giving reliable results in 3h, the RT-qPCR method has high potential as a rapid test for recreational water quality monitoring. In natural waters, significant linear log-log relations between the RT-qPCR and culture method measurements for E. coli and Enterococcus spp. assays were shown (correlation coefficient (r) values of 0.814 and 0.715, p<0.0001, respectively). The sensitivities (defined as the probability of a sample testing positive if the criterion number is exceeded) of RT-qPCR for E. coli and Enterococcus spp. were respectively 94.4% and 83.9%. By contrast, specificities (defined as the probability of a test being negative if a contamination is truly absent) could be considered as lower (65.9% and 50.0% for E. coli and Enterococcus spp.). This reflects that RT-qPCR assays detect all viable cells (culturable and non-culturable) whereas culture methods only detect cells which are viable and culturable.


Subject(s)
Enterococcus/isolation & purification , Escherichia coli/isolation & purification , Water Microbiology , Bathing Beaches/standards , Reverse Transcriptase Polymerase Chain Reaction , Seawater/microbiology
8.
J Evol Biol ; 24(8): 1685-94, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21585586

ABSTRACT

Mate selection for inbreeding avoidance is documented in several taxa. In mammals, most conclusive evidence comes from captive experiments that control for the availability of mates and for the level of genetic relatedness between mating partners. However, the importance of mate selection for inbreeding avoidance as a determinant of siring success in the wild has rarely been addressed. We followed the reproduction of a wild population of eastern chipmunks (Tamias striatus) during five breeding seasons between 2006 and 2009. Using molecular tools and parentage assignment methods, we found that multiple paternity (among polytocous litters) varied from 25% in an early-spring breeding season when less than a quarter of females in the population were reproductively active to 100% across three summer breeding seasons and one spring breeding season when more than 85% of females were reproductively active. Genetically related parents were common in this population and produced less heterozygous offspring. Furthermore, litters with multiple sires showed a higher average relatedness among partners than litters with only a single sire. In multiply sired litters, however, males that were more closely related to their partners sired fewer offspring. Our results corroborate findings from captive experiments and suggest that selection for inbreeding avoidance can be an important determinant of reproductive success in wild mammals.


Subject(s)
Inbreeding , Mating Preference, Animal , Sciuridae/physiology , Animals , Female , Genotype , Male , Microsatellite Repeats
9.
J Cardiovasc Surg (Torino) ; 51(1): 85-93, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20081764

ABSTRACT

Thoracic endovascular aortic repair (TEVAR) has emerged as promising and a less invasive alternative to open surgery for high risk patients (HRP) with type B thoracic aortic dissection (TAD). One of the most serious complication of TEVAR is the retrograde type A TAD (rATAD). This review will focus on an interesting rATAD case and will review the literature, regarding the true incidence, mortality, causes, diagnosis, complications and management of rATAD. Until the development of a specific device for TAD, efforts must be made for better patient and device selection, careful and precise instrumentation, and life-long surveillance to minimize this lethal complication.


Subject(s)
Aortic Aneurysm, Thoracic/surgery , Aortic Dissection/surgery , Blood Vessel Prosthesis Implantation/instrumentation , Blood Vessel Prosthesis , Stents , Aortic Dissection/diagnostic imaging , Aortic Aneurysm, Thoracic/diagnostic imaging , Aortography/methods , Blood Vessel Prosthesis Implantation/adverse effects , Humans , Prosthesis Design , Recurrence , Tomography, X-Ray Computed , Treatment Outcome
10.
J Cardiovasc Surg (Torino) ; 50(5): 677-81, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19455084

ABSTRACT

Carotid angioplasty and stenting (CAS) is a well established technique. CAS indications currently still limited are yet evolving. The choice of the access is defined by the risk factors of the patient among whom ''the vascular anatomy'' is essential. The authors will focus here on the accesses, their advantages and their drawbacks. They made a retrospective study relating 314 patients treated by CAS. No significant difference in term of morbidity or mortality between the cervical or femoral access was found but a clear tendency in favor of the cervical access which avoids the arch manipulations. It can be concluded that various access offer better options for CAS and must be discussed depending on the patient's anatomy and risks factors.


Subject(s)
Angioplasty, Balloon , Carotid Arteries , Carotid Artery Diseases/therapy , Femoral Artery , Patient Selection , Stents , Angioplasty, Balloon/adverse effects , Angioplasty, Balloon/instrumentation , Angioplasty, Balloon/methods , Humans , Ischemic Attack, Transient/etiology , Retrospective Studies , Risk Assessment , Stroke/etiology
11.
J Cardiovasc Surg (Torino) ; 50(2): 189-93, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19329915

ABSTRACT

AIM: The aim of this study was to evaluate the usefulness of the temporal approach during coronary artery stenosis (CAS) to overcome tortuosity in case of difficult arch anatomy or tortuous common carotid artery, and to provide cerebral protection of proximal lesions of the supra-aortic trunks during stenting. METHODS: The superficial temporal artery is exposed through a small incision right in front of the ear and is cannulated. A guidewire is used to descend in the external and common carotid artery and in the arch if needed. Between the end of March 2007 and May 2008 9 patients were treated with the temporal approach: in 5 cases of stenosis of the internal carotid artery with difficult arch anatomy to obtain a through and through guide from the temporal to the femoral artery, in 3 of the supra-aortic trunks to obtain cerebral protection during the procedure and in one case of tandem lesion of the left common and internal carotid artery. RESULTS: The procedure was successful in all 9 cases and there were no complications. CONCLUSIONS: The temporal approach proved to be feasible and at low risk; it represents a new possibility to increase the feasibility of carotid artery stenting in patients with difficult anatomy but, above all, it is a good way to obtain cerebral protection during endovascular treatment of proximal lesions of the supra-aortic vessels.


Subject(s)
Angioplasty, Balloon/methods , Carotid Stenosis/therapy , Catheterization, Peripheral , Stroke/prevention & control , Temporal Arteries , Aged , Aged, 80 and over , Angioplasty, Balloon/adverse effects , Angioplasty, Balloon/instrumentation , Carotid Stenosis/diagnostic imaging , Catheterization, Peripheral/adverse effects , Feasibility Studies , Female , Humans , Male , Radiography , Stents , Stroke/etiology , Treatment Outcome
12.
J Cardiovasc Surg (Torino) ; 48(6): 689-95, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17947925

ABSTRACT

AIM: This registry aims at evaluating the use and efficacy of the EndoFit stent graft (LeMaitre Vascular, Burlington MA, USA) for the treatment of acute and chronic aortic type B dissections. METHODS: Indications for treatment are: recurrent pain, persistent hypertension, serious organ malperfusion in patients with acute or subacute type B aortic dissection and progression of aneurysm size despite maximal medical therapy in patient with chronic type B dissection. Exclusion criteria are: age under 18 years old, pregnancy, coagulopathy or bleeding disorders, connective tissue disease. Straight or tapered EndoFit stent graft will be used in acute or chronical dissection respectively. RESULTS: The primary endpoint is the assessment of the safety and the efficacy of the EndoFit Thoracic Endoluminal Stent Graft in the exclusion of the thoracic aortic false lumen in acute and chronic type B aortic dissections. The assessment includes: technical success, thrombosis of the thoracic false lumen at 6 months, rate of aorto-enteric, aorto-esophageal and aorto-bronchial fistula, serious adverse events including death, stroke, paraplegia, myocardial infarction, multi-organ failure and renal insufficiency. Secondary endpoints are: the technical feasibility of device implantation in 2 different shapes (straight for acute dissection and tapered for chronic dissection), the technical feasibility of endovascular placement of tapered grafts in vessels of different size and shape, the integrity of the device fabric and wire structure, the occurrence of device migration, the patient's neurological, cardiac and cardiovascular status, the blood flow supply to abdominal and visceral organs arteries and any secondary intervention including stentgraft extension, coiling or surgical conversion. One hundred patients enrolled have been defined to allow reliable findings and results. CONCLUSION: The DEDICATED is the first prospective data collection registry focusing on the role of tapered stentgrafts in chronic aortic dissection and their efficacy in excluding the dissected thoracic false lumen.


Subject(s)
Aortic Aneurysm, Thoracic/epidemiology , Aortic Aneurysm, Thoracic/surgery , Aortic Dissection/epidemiology , Aortic Dissection/surgery , Blood Vessel Prosthesis , Registries , Stents , Acute Disease , Alloys , Chronic Disease , Disease Progression , Europe/epidemiology , Humans , Pilot Projects , Polytetrafluoroethylene , Prospective Studies , Prosthesis Design , Safety , Treatment Outcome
13.
J Cardiovasc Surg (Torino) ; 48(6): 805-7, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17947941

ABSTRACT

The proper identification of the proximal landing zone prior to aortic stentgraft deployment is a key step that impacts the global outcome of the procedure. We report an intraoperative technique during total aortic arch transposition that facilitates subsequent endovascular arch exclusion thanks to a reliable radio-opaque marker. In patients who require an endovascular exclusion of the aortic arch, a total arch transposition can be performed through a median sternotomy prior to stentgraft deployment. During the surgical stage, a radio-opaque thread is pull out of a surgical sponge pad, looped around the ascending aorta just distal to the ostium of the aorto-innominate bypass and fixed in place by means of metal clips. The technique we describe increases the accuracy of stentgraft deployment in the ascending aorta after total arch transposition. It will potentially improve the outcome.


Subject(s)
Aorta, Thoracic/anatomy & histology , Aorta, Thoracic/surgery , Blood Vessel Prosthesis Implantation/methods , Stents , Transposition of Great Vessels/surgery , Humans
14.
J Cardiovasc Surg (Torino) ; 47(5): 497-502, 2006 Oct.
Article in English | MEDLINE | ID: mdl-17033598

ABSTRACT

AIM: The standard approach for treating acute Type A aortic dissections (TAD) is replacement of the ascending aorta utilizing hypothermic circulatory arrest (HCA), which is associated with significant morbidity and frequently leaves a residual aortic arch dissection. We describe a staged surgical and endovascular technique of ascending aorta replacement and simultaneous aorto-innominate artery bypass without HCA, followed 4 weeks later by carotid-carotid bypass and endovascular exclusion of the remaining arch dissection with a thoracic endograft. METHODS: From December 2004 to December 2005, 5 consecutive patients (mean age 58 +/- 6.9 years) with TADs underwent the staged procedure. All patients underwent replacement of the ascending aorta and aorto-innominate bypass. Two patients subsequently underwent the second endovascular stage. In one patient the aortic false lumen completely thrombosed following the first surgical stage and two patients are currently awaiting the endovascular stage. RESULTS: There were no major adverse events (death, cerebrovascular accident or paraplegia) following the first surgical stage. One patient suffered a transient minor stroke. The 2 patients who underwent the second endovascular stage showed no immediate adverse events. Postoperative CT scans have demonstrated that the false channel was excluded from the aortic arch down to the distal end of the endograft in the descending aorta in each case, but became patent further downstream. CONCLUSIONS: This procedure appears safe and feasible. It may allow for a more definitive treatment of TADs than the standard surgical approach. It can be adapted by low volume centers, surgeons untrained in aortic arch repair, and in high risk patients.


Subject(s)
Aortic Aneurysm, Thoracic/surgery , Aortic Dissection/surgery , Blood Vessel Prosthesis Implantation/methods , Stents , Acute Disease , Aortic Dissection/diagnostic imaging , Aortic Aneurysm, Thoracic/diagnostic imaging , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prosthesis Design , Retrospective Studies , Tomography, X-Ray Computed , Treatment Outcome
15.
Acta Chir Belg ; 106(2): 230-2, 2006.
Article in English | MEDLINE | ID: mdl-16761486

ABSTRACT

PURPOSE: To report simultaneous endovascular repair of tandem proximal common carotid artery and internal carotid artery in a patient with complex post-radiotherapy lesions. CASE REPORT: A 67-year-old woman with a medical history of cervical and thoracic radiotherapy and claudication, was admitted with the diagnosis of critical inferior limb ischaemia (stage III-Fontaine) and two recents episodes of amaurosis fugax of the left eye. Duplex Scan and M.R. Angiography revealed high grade stenosis of the proximal left common and internal carotid artery and a complete bilateral iliac artery occlusion. A synchronous ante- and retro-grade carotid endovascular treatment was performed in the first stage of the treatment, allowed by an open minimal cervical access under cerebral filter protection (Angio-Guard system, Cordis corp.). The post-operative period was uneventful. The patient underwent a succesful aortobifemoral reconstruction soon afterwards. At 26 months, the patient was asymptomatic. Duplex Scan confirmed a good patency of the carotid stents with normal cerebral CT Scan. CONCLUSIONS: Serial common and internal carotid lesions appear amenable to concomitant ante- and retro-grade endovascular repair in selected patients.


Subject(s)
Angioplasty , Carotid Artery, Common , Carotid Artery, Internal , Carotid Stenosis/surgery , Stents , Aged , Angiography , Arteritis/complications , Arteritis/diagnostic imaging , Arteritis/surgery , Atherosclerosis/complications , Atherosclerosis/diagnostic imaging , Atherosclerosis/surgery , Carotid Artery, Common/diagnostic imaging , Carotid Artery, Internal/diagnostic imaging , Carotid Stenosis/diagnostic imaging , Carotid Stenosis/etiology , Female , Humans , Radiotherapy/adverse effects
16.
J Cardiovasc Surg (Torino) ; 47(2): 143-51, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16572088

ABSTRACT

AIM: Carotid stenting (CS) has proved to be a safe alternative to carotid endarterectomy, and subsets of patients who may benefit from carotid stents rather than surgery still need to be defined. Randomized trials and individual series are looking at predicting factors of early outcome after carotid angioplasty and stenting (CAS) that can hardly be applied to all series. We analyzed early results of the Eurocast registry and discussed the potential role of multicentric registries in determining such outcome predictors. METHODS: The Eurocast registry is an online prospective registry on CAS that collected 897 procedures from February 2000 to December 2005 across 20 centers. Statistical analyses were performed with the univariate Fisher's exact test on CS procedures, excluding sole balloon angioplasty. Risk factors reported were hypertension, hyperlipidemia, past or current history of smoking, diabetes mellitus, obesity, cardiac disease, other vascular disease, pulmonary disease, hostile neck and renal failure. Half of patients (50.2%) had symptomatic carotid lesions. Local anesthesia (91.8%) and retrograde femoral access (95.6%) were the preferred method. Overall procedures were achieved in 98.2%, of which 84.5% were performed under cerebral protection. RESULTS: Intraoperative neurological complications occurred in 26 (3.1%) of 824 procedures achieved. No immediate deaths were reported. The intraoperative ipsilateral stroke/death rate was 1.7%. The overall in-hospital stroke/death rate was 3.5%. Significant predictors of early neurological complications were infarctions on preoperative cerebral CT scanning, a deficient circle of Willis, a too short preoperative length of medication (7 days or less), any additional intervention (stenting and/or balloon dilatation), bradycardia and hypotension. Less reliable predictors were: age >70 years, renal failure, preoperative speech or motor deficit, postradiation stenosis, lesion on the left carotid axis and lesion on the common carotid artery. CONCLUSIONS: This analysis confirmed that CS is a feasible and secure technique to treat carotid stenosis. However, the determination of neurological outcome predictors remains subject to further confirmation. Other patient subgroups identified in other studies (female sex, diabetics, coronary disease) should be investigated more precisely. Finally, the Eurocast analysis showed that the setting up of risk scores would be dependent on local practices, physicians' experience and would not be reproducible.


Subject(s)
Angioplasty , Carotid Stenosis/surgery , Registries , Stents , Adult , Age Factors , Aged , Aged, 80 and over , Angioplasty/adverse effects , Carotid Stenosis/diagnostic imaging , Cohort Studies , Europe , Female , Humans , Internet , Intracranial Embolism/etiology , Intracranial Embolism/prevention & control , Male , Middle Aged , Predictive Value of Tests , Radiography , Risk Factors , Severity of Illness Index , Treatment Outcome
17.
Eur J Vasc Endovasc Surg ; 32(1): 38-45, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16520069

ABSTRACT

OBJECTIVES: To evaluate a recent approach for the endovascular repair of thoracic aortic aneurysms and dissections involving the aortic arch in high risk patients (HRP). METHODS: Amongst 102 thoracic aortic aneurysms and dissections, we treated 25 patients for aortic arch endovascular exclusion after transposition of the great vessels, of which 14 (56%) had thoracic aortic arch aneurysms and 11 type A and B chronic aortic dissections. Total transpositions were done in 15 cases (60%) and hemi-arch transpositions in 10. We then used Talent, Excluder and Zenith endografts in 12, seven and six cases, respectively. RESULTS: Surgical transpositions were complicated by one minor stroke, which worsened to a major stroke (4%) after endovascular exclusion. After endovascular exclusions, two patients (8%) died from catheterization related complications. One patient had a delayed minor stroke (4%). The successful exclusion rate was 92%. During follow-up (15+/-5.8 months), one patient (4%) developed unilateral limb palsy, successfully treated by CSF drainage. The late exclusion rate remained 92%. No stent-related complications were seen. CONCLUSIONS: Transposition of supra-aortic vessels allows the endovascular exclusion of the aortic arch in HRP. Aortic endografting after surgical transposition proved to be feasible and offers good mid-term results. Specialized surgical centers with both endovascular and surgical expertise are required to treat these patients.


Subject(s)
Aorta, Thoracic/surgery , Aortic Aneurysm, Thoracic/surgery , Aortic Dissection/surgery , Aged , Aged, 80 and over , Anastomosis, Surgical , Aortic Aneurysm, Thoracic/pathology , Blood Vessel Prosthesis Implantation , Catheterization , Female , Humans , Male , Middle Aged , Postoperative Complications/etiology , Retrospective Studies , Stents , Stroke/etiology , Tomography, X-Ray Computed
18.
J Cardiovasc Surg (Torino) ; 46(2): 141-7, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15793493

ABSTRACT

AIM: We describe our experience in endovascular repair of Thoracic Aortic Aneurysms and Dissections (TAAD) involving the aortic arch in high risk patients (HRP). METHODS: Twenty-nine patients presented with TAAD involving the aortic arch and were treated by endovascular exclusion. Pathologies were as follows: atherosclerotic aneurysms of the descending thoracic aorta in 15 cases, acute Stanford type A dissections in 6 cases, Stanford type B dissections in 7 cases (1 acute), and 1 false aneurysm of the ascending aorta. Total-arch transpositions of all supra-aortic vessels (aortic debranching) to the ascending aorta were done in 11 cases throught median sternotomy. We performed carotido-carotid bypass (hemi-arch transposition) in 16 patients by cervicotomy. Secondary to surgical transpositions, we placed endovascular stentgrafts in all but 2 patients for final exclusion, the 2 remaining being planned for later exclusion. The Talent, Excluder, TAG and Zenith endografts were used in 12, 3, 1 and 4 cases respectively. Banding technique was associated in some cases. RESULTS: All surgical transpositions were successful although 1 led to a minor stroke (1/29=3.5%), which worsened to major stroke after endovascular exclusion. Endovascular procedures were performed in all but one case (26/27=96.3%). Two patients (2/26=7.7%) died from catheterization related complications after endovascular exclusion (iliac rupture and left ventricle perforation). One patient had a delayed minor stroke (1/26=3.8%). Recirculation was found in 13.3% (2/15) of aneurysms and 27.3% of thoracic false channels. During a mean follow-up of 15.7 months (13 days to 45.5 months), 1 patient (1/26=3.8%) who had preoperative chronic pulmonary failure died at 6 months from respiratory worsening. We observed one case (3.8%) of unilateral limb palsy unrelated to cerebral ischemia, which we successfully treated by cerebrospinal fluid (CSF) drainage. No stent-related complication was seen. One new type 1 endoleak appeared at 12 months on an aneurysm, which resolved after stentgraft extension. Three thoracic dissection false channels remained patent during follow-up, of which one was retrograde originating distally in the descending aorta. CONCLUSIONS: Secondary endovascular exclusion of thoracic aortic diseases involving the arch in HRP is made feasible thanks to the preliminary aortic debranching. Total-arch transposition may be of greater interest in case of proximal neck length uncertainty and potential embolization from the aortic arch. Mid-term results are good although patients must be followed carefully to detect aortic recirculation and enlargement.


Subject(s)
Aorta, Thoracic , Aortic Aneurysm, Thoracic/surgery , Aortic Dissection/surgery , Blood Vessel Prosthesis Implantation , Aged , Aged, 80 and over , Aortic Dissection/diagnostic imaging , Aorta, Thoracic/diagnostic imaging , Aorta, Thoracic/pathology , Aorta, Thoracic/surgery , Aortic Aneurysm, Thoracic/diagnostic imaging , Blood Vessel Prosthesis Implantation/adverse effects , Blood Vessel Prosthesis Implantation/instrumentation , Female , Follow-Up Studies , Humans , Male , Middle Aged , Retrospective Studies , Stents , Survival Rate , Treatment Outcome , Ultrasonography, Interventional
19.
J Cardiovasc Surg (Torino) ; 44(3): 349-61, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12832988

ABSTRACT

UNLABELLED: Descending thoracic aortic aneurysms (TAA) and chronic dissections have high morbidity and mortality rates. For 10 years, the evolution of both imaging techniques and aortic stent-graft design has brought a new therapeutic hope for patients at high risk for surgery presenting non-ruptured or emergency cases of TAA. Our goal is to describe the endovascular technique, review its state of the art and compare its mid-term results to those of conventional surgery. We also describe surgical ways to manage complex TAA, involving the aortic arch and/or the celiac aorta, as therapeutic solutions for high risk patients for surgery with unfitted anatomy for endovascular repair. After a review of the literature dealing with the natural history, the etiology, and the surgical treatment, we describe the endovascular devices, the conventional stent-grafting technique and we detail the adjunctive procedures we used to manage complex cases. We then retrospectively report our personal 38-patient experience from October 1999 to February 2003. Thirty-three patients presented with TAA and the average age was 70 years old (35-88), while the male/female ratio was 5.3. All of them were at high risk for surgery, of which 27% required adjunctive procedures to achieve proximal and/or distal neck management. The in-hospital death rate was 9%. We reported no case of paraplegia and only 1 patient with post-operative regressive stroke (3%). All the aneurysmal sacs were successfully excluded without early endoleak. During follow-up period (mean: 2 years; 1-40 months), we observed a late death rate of 10%. All aneurysmal sac remained excluded by the endografts and no stent-graft migration was observed. No late endoleak appeared during the follow-up course, but 1 patient presented a proximal aortic enlargement, which required total transposition of the supra-aortic vessels and stent-graft extension. The endovascular repair of TAA and chronic dissections proved to be feasible and offers hopeful mid-term RESULTS: With a very low morbidity-mortality rate, compared to surgery, the endovascular technique may represent an unquestionable therapeutic options, especially for patients at high risk for surgery. However, long-term results are needed to point out the durability of descending thoracic aortic stent-grafting. Neck management must be encouraged in order to avoid type 1 endoleaks in cases with short landing zones.


Subject(s)
Angioplasty/instrumentation , Aortic Aneurysm, Thoracic/therapy , Aortic Dissection/therapy , Arteriosclerosis/therapy , Blood Vessel Prosthesis , Stents , Adult , Aged , Aged, 80 and over , Aortic Dissection/diagnostic imaging , Aortic Dissection/mortality , Aortic Aneurysm, Thoracic/diagnostic imaging , Aortic Aneurysm, Thoracic/mortality , Aortography , Arteriosclerosis/diagnostic imaging , Arteriosclerosis/mortality , Combined Modality Therapy , Comorbidity , Female , Follow-Up Studies , Hospital Mortality , Humans , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Male , Middle Aged , Postoperative Complications/diagnostic imaging , Postoperative Complications/mortality , Risk , Survival Analysis
20.
J Vasc Surg ; 33(2 Suppl): S111-6, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11174821

ABSTRACT

OBJECTIVE: Carotid bifurcation angioplasty and stenting (CBAS) has generated controversy and widely divergent opinions about its current therapeutic role. To resolve differences and establish a unified view of CBAS' present role, a consensus conference of 17 experts, world opinion leaders from five countries, was held on November 21, 1999. METHODS: These 17 participants had previously answered 18 key questions on current CBAS issues. At the conference these 18 questions and participants' answers were discussed and in some cases modified to determine points of agreement (consensus), near consensus, (prevailing opinion), or divided opinion (disagreement). RESULTS: Conference discussion added two modified questions, placing a total of 20 key questions before the participants, representing four specialties (interventional radiology, seven; vascular surgery, six; interventional cardiology, three; neurosurgery, one). It is interesting that consensus was reached on the answers to 11 (55%) of 20 of the questions, and near consensus was reached on answers to 6 (30%) of 20 of the questions. Only with the answers to three (15%) of the questions was there persisting controversy. Moreover, both these differences and areas of agreement crossed specialty lines. Consensus Conclusions: CBAS should not currently undergo widespread practice, which should await results of randomized trials. CBAS is currently appropriate treatment for patients at high risk in experienced centers. CBAS is not generally appropriate for patients at low risk. Neurorescue skills should be available if CBAS is performed. When cerebral protection devices are available, they should be used for CBAS. Adequate stents and technology for performing CBAS currently exist. There were divergent opinions regarding the proportions of patients presently acceptable for CBAS treatment (<5% to 100%, mean 44%) and best treated by CBAS (<3% to 100%, mean 34%). These and other consensus conclusions will help physicians in all specialties deal with CBAS in a rational way rather than by being guided by unsubstantiated claims.


Subject(s)
Angioplasty/methods , Carotid Artery Diseases/surgery , Patient Selection , Practice Guidelines as Topic/standards , Stents , Angioplasty/instrumentation , Attitude of Health Personnel , Benchmarking , Clinical Competence/standards , Diffusion of Innovation , Evidence-Based Medicine , Humans , Needs Assessment , Research , Risk Factors , Treatment Outcome
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