Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Vasc Surg ; 77(2): 642-649.e4, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35850164

RESUMEN

BACKGROUND: Aberrant subclavian artery (AScA) with or without associated Kommerell's diverticulum (KD) is the most frequently encountered anomaly of the aortic arch, it may be life threatening, especially when associated with aneurysmal degeneration. The best management is still debated and depends on many clinical and anatomical factors. A systematic review was conducted to assess the current evidence on the treatment options and their efficacy and safety for AscA and KD repairs. METHODS: A literature search in PubMed and Cochrane Library was performed, and articles that were published from January 1947 to August 2021 reporting on AscA and KD management were identified. Multicenter studies, single-center series, and case series with three or more patients were considered eligible in the present review. A comparison of outcomes of patients who underwent open surgery (OS), a hybrid approach (HA), and total endovascular repair (ER) (ie, 30-day mortality and stroke were analyzed when available and compared among the three groups (P < .05; Benjamini and Hochberg-adjusted P < .05; Bonferroni-adjusted P < .05). Titles, abstracts, and full texts were evaluated by two authors independently. Primary outcomes included survival rate, perioperative stroke, arm ischemia, and spinal cord ischemia. Endoleak, in the case of HA and ER, and reintervention rates were considered outcomes. RESULTS: Three hundred thirty-one articles were initially evaluated and 30 studies, totaling 426 patients treated for AScA with 324 KD, were included. Of the 426 patients, 241 were male (56.5%), and the mean patient age was 57.9 ± 12.0 years. The approach was OS in 228 patients, HA in 147 patients, and ER in 51. Dysphagia was the most common presentation in 133 cases. Aortic rupture was observed in 16 of the 426 patients (3.8%), including 14 AScA/KD (3.3%) aneurysm rupture. KD maximum diameter varied widely from 12.6 to 63.6 mm. The overall 30-day mortality was 20 (4.7%) (OS group 8/228 [3.5%]; HA group 10/147 [6.8%]; ER 2/51 [3.9%]; P = NS). The overall stroke rate was 4.9% (21/426) (OS group 10/228 [4.4%]; HA group 6/147 [4.1%]; ER group 5/51 [9.8%]; P = NS), including nine transient and nondisabling neurological deficits. Overall secondary procedures for complications were reported in 36 of the 426 cases (8.4%), mostly owing to endoleak. Follow-up varied from 13 to 74 months. CONCLUSIONS: This systematic review assessed the current outcomes of the three types of therapeutic management for AScA and KD and demonstrated that they are all relatively safe and effective, providing satisfactory early and midterm outcomes. Long-term outcomes are warranted, especially for total ERs since the long-term durability of stent grafts remains unknown.


Asunto(s)
Rotura de la Aorta , Divertículo , Procedimientos Endovasculares , Humanos , Masculino , Persona de Mediana Edad , Anciano , Femenino , Endofuga/complicaciones , Aorta Torácica/diagnóstico por imagen , Aorta Torácica/cirugía , Aorta Torácica/anomalías , Arteria Subclavia/diagnóstico por imagen , Arteria Subclavia/cirugía , Arteria Subclavia/anomalías , Rotura de la Aorta/etiología , Procedimientos Endovasculares/efectos adversos , Divertículo/diagnóstico por imagen , Divertículo/cirugía , Resultado del Tratamiento
2.
J Vasc Surg ; 78(6): 1409-1417, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37572890

RESUMEN

OBJECTIVE: In the majority of patients with chronic type B aortic dissection, there is persistent retrograde flow in the false lumen (FL) through distal re-entry tears. Among several endovascular techniques proposed for FL management, the "Candy Plug" (CP) technique has gained acceptance with good early results. The aim of this study is to report the types and outcomes of open and endovascular reinterventions and identify mechanisms of procedure failure as well as other causes for reinterventions. METHODS: All patients with type B aortic dissection submitted to thoracic endovascular aneurysm repair and CP implantation for FL embolization from January 2016 to December 2022 at our institution were included in this study. The preoperative, intraoperative, and postoperative data of the primary intervention and secondary reinterventions, when performed, were prospectively collected and retrospectively analyzed. Preoperative and postoperative computed tomography angiography were also analyzed. RESULTS: During the study period, 33 patients were submitted to thoracic endovascular aneurysm repair and CP implantation. Twenty-three patients (69.7%) showed thoracic FL complete thrombosis with aortic stability or positive remodeling at a mean follow-up of 45 ± 23.1 months. Ten patients (30.3%) underwent aortic reinterventions (male, n = 9; mean age, 60.5 ± 7.6 years). Of these 10 patients, in four patients, complete thrombosis of the FL was never achieved, leading to ongoing perfusion of the FL, defined as "primary failure." The other six patients underwent reinterventions for different causes: two patients, after initial sealing, showed a progressive enlargement of the abdominal FL leading to distal degeneration. One patient showed proximal degeneration, two patients showed a type II thoracoabdominal aortic aneurysm and CP implantation was used as a planned procedure to reduce the extent of the surgical procedure, and one patient had recurrent, intractable back pain despite complete thrombosis of the FL. Reinterventions were open in five cases and endovascular in five. One in-hospital death (postoperative day 27) after a type II thoracoabdominal aortic aneurysm open repair was recorded. In addition, two cases of delayed spinal cord ischemia after open reintervention were recorded: one resulting in permanent paraplegia and one transitory with complete recovery. CONCLUSIONS: The CP technique was safe and effective; however, a significant rate of aortic-related reintervention was observed. Several mechanisms led to reinterventions either in terms of "primary failure" of the CP or subsequent aneurysmal degeneration. Complex reinterventions were often necessary, with a high rate of major complications in case of open repair. Life-long and closer surveillance might be required in these patients.


Asunto(s)
Aneurisma de la Aorta Abdominal , Aneurisma de la Aorta Toracoabdominal , Disección Aórtica , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Trombosis , Humanos , Masculino , Persona de Mediana Edad , Anciano , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/cirugía , Mortalidad Hospitalaria , Estudios Retrospectivos , Implantación de Prótesis Vascular/efectos adversos , Procedimientos Endovasculares/efectos adversos , Disección Aórtica/diagnóstico por imagen , Disección Aórtica/cirugía
3.
J Vasc Surg ; 77(2): 347-356.e2, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36243266

RESUMEN

OBJECTIVE: In the field of thoracoabdominal aortic aneurysm (TAAA) open surgical repair (OSR), some preoperative characteristics are established risk factors for adverse outcomes, whereas others are supposed to be relevant, but their role still need to be defined; among them, the presence of "shaggy aorta" (SA), an extensive and irregular atheroma within the aorta. The aim of this study is to report the results of a single-center large cohort of patients treated with OSR for TAAA with SA, comparing the outcomes with patients affected by TAAA without SA, and analyzing the impact of the scores for SA on the outcomes. METHODS: All consecutive patients receiving OSR for TAAA between 2012 and 2021 were retrospectively analyzed. Clinical data from patients with degenerative TAAA were included and analyzed for preoperative characteristics and postoperative outcomes; patients with ruptured TAAA, and patients with aortic dissection were excluded from the analysis. Patients with degenerative aortic aneurysm, thrombus measurement in non-aneurysmal aortic segments (≤40 mm), atheroma thickness ≥5 mm, and finger-like thrombus projection were included in the SA group, whereas the others were included in the non-shaggy aorta group (NSA group). The SA group and NSA group were compared using a propensity-matched comparison. Preoperative computed tomography scans of patients in the SA group were also stratified according to SA grading scores. RESULTS: A total of 58 patients with SA were identified (male, n = 43 [74.1%], mean age 70.1 ± 7.8 years) among 497 patients with TAAA treated with open surgical repair. After propensity matching, there were 57 patients in the SA group and 57 in the NSA group with correction of all differences in baseline characteristics. Patients in the SA group presented significantly higher in-hospital mortality (SA group, 14.0% vs NSA group, 3.5%; P = .047), postoperative acute renal failure (Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease [RIFLE], 3-5) (SA group, 21.1% vs NSA group, 5.3%; P = .013), and postoperative embolization (SA group, 28.1% vs NSA group, 8.8%; P = .008). Spinal cord ischemia and stroke rate were not significantly influenced by the presence of SA. In the SA group, 16 patients (27.6%) with end-organ embolization were compared with 42 patients (72.4%) without a documented embolization considering the grade of aortic "shagginess" and no significant difference was identified (P = .546). CONCLUSIONS: Despite a better knowledge of the SA disease, new classifications, and intraoperative adjuncts, TAAA patients with SA treated with OSR have worse postoperative outcomes if compared with patients without SA. The presence of SA is a risk factor itself, whereas the grade of "shagginess" seems not to impact on postoperative outcomes.


Asunto(s)
Lesión Renal Aguda , Aneurisma de la Aorta Torácica , Aneurisma de la Aorta Toracoabdominal , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Placa Aterosclerótica , Trombosis , Humanos , Masculino , Persona de Mediana Edad , Anciano , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/cirugía , Placa Aterosclerótica/complicaciones , Estudios Retrospectivos , Resultado del Tratamiento , Factores de Riesgo , Aorta/cirugía , Lesión Renal Aguda/etiología , Trombosis/etiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Procedimientos Endovasculares/efectos adversos
4.
J Vasc Surg ; 78(4): 863-873.e3, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37330705

RESUMEN

OBJECTIVE: Analyze the outcomes of endovascular complex abdominal and thoracoabdominal aortic aneurysm repair using the Cook fenestrated device with the modified preloaded delivery system (MPDS) with a biport handle and preloaded catheters. METHODS: A multicenter retrospective single arm cohort study was performed, including all consecutive patients with complex abdominal aortic aneurysm repair and thoracoabdominal aortic aneurysms treated with the MPDS fenestrated device (Cook Medical). Patient clinical characteristics, anatomy, and indications for device use were collected. Outcomes, classified according to the Society for Vascular Surgery reporting standards, were collected at discharge, 30 days, 6 months, and annually thereafter. RESULTS: Overall, 712 patients (median age, 73 years; interquartile range [IQR], 68-78 years; 83% male) from 16 centers in Europe and the United States treated electively were included: 35.4% (n = 252) presented with thoracoabdominal aortic aneurysms and 64.6% (n = 460) with complex abdominal aortic aneurysm repair. Overall, 2755 target vessels were included (mean ,3.9 per patient). Of these, 1628 were incorporated via ipsilateral preloads using the MPDS (1440 accessed from the biport handle and 188 from above). The mean size of the contralateral femoral sheath during target vessel catheterization was 15F ± 4, and in 41 patients (6.7%) the sheath size was ≤8F. Technical success was 96.1%. Median procedural time was 209 minutes (IQR, 161-270 minutes), contrast volume was 100 mL (IQR, 70-150mL), fluoroscopy time was 63.9 minutes (IQR, 49.7-80.4 minutes) and median cumulative air kerma radiation dose was 2630 mGy (IQR, 838-5251 mGy). Thirty-day mortality was 4.8% (n = 34). Access complications occurred in 6.8% (n = 48) and 30-day reintervention in 7% (n = 50; 18 branch related). Follow-up of >30 days was available for 628 patients (88%), with a median follow-up of 19 months (IQR, 8-39 months). Branch-related endoleaks (type Ic/IIIc) were observed in 15 patients (2.6%) and aneurysm growth of >5 mm was observed in 54 (9.5%). Freedom from reintervention at 12 and 24 months was 87.1% (standard error [SE],1.5%) and 79.2% (SE, 2.0%), respectively. Overall target vessel patency at 12 and 24 months was 98.6% (SE, 0.3%) and 96.8% (SE, 0.4%), respectively, and was 97.9% (SE, 0.4%) and 95.3% (SE, 0.8%) for arteries stented from below using the MPDS, respectively. CONCLUSIONS: The MPDS is safe and effective. Overall benefits include a decrease in contralateral sheath size in the treatment of complex anatomies with favorable results.


Asunto(s)
Aneurisma de la Aorta Abdominal , Aneurisma de la Aorta Torácica , Aneurisma de la Aorta Toracoabdominal , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Humanos , Masculino , Anciano , Femenino , Prótesis Vascular , Reparación Endovascular de Aneurismas , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/cirugía , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/cirugía , Estudios Retrospectivos , Estudios de Cohortes , Resultado del Tratamiento , Factores de Tiempo , Diseño de Prótesis
5.
J Vasc Surg ; 73(1): 81-91, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32442603

RESUMEN

OBJECTIVE: The objective of this study was to evaluate the performance of percutaneous femoral access with large-bore sheaths (>21F outer diameter) mainly employed for thoracic and thoracoabdominal aortic endovascular treatment and to stratify the outcomes on the basis of the introducer size. METHODS: Between December 2015 and December 2018, all consecutive patients who received endovascular repair through a percutaneous approach with a suture-mediated vascular closure device (VCD) and the preclose technique were included in a retrospective single-center study called Totally Percutaneous Approach to Endovascular Treatment of Aortic Aneurysms (PEVAR-PRO). The morphologic characteristics of the access vessels and patients' demographics were recorded, and 30-day closure success was defined as the primary end point. Analysis of the closure success comparing large-bore sheaths vs small-bore sheaths (≤21F outer diameter) was performed after 1:1 propensity score matching of preoperative confounding variables. RESULTS: The closure success rate of the entire study cohort was 94% (622 femoral accesses in 360 patients; median age, 74 years; 84% male). Univariate analysis identified eight different factors associated with failure, but only two remained significant on multivariate analysis: diabetes (odds ratio [OR], 2.8; 95% confidence interval [CI], 1.3-6.2; P = .011) and common femoral artery stenosis >50% (OR, 4.5; 95% CI, 1.3-13.7; P = .019). After propensity score matching (1:1, 172 femoral accesses per group), closure success rate was not significantly different between large-bore and small-bore sheaths (90.7% vs 93.0%; P = .43). Multivariate analysis of the large-sheath group identified two factors associated with failure: small (<9 mm) femoral arteries (OR, 6.9; 95% CI, 1.5-31.6; P = .13) and access vessel calcifications involving more than one-third of the circumference (OR, 7.9; 95% CI, 2.1-29.4; P = .002). Neither previous femoral cutdown (44 accesses [23%]) nor percutaneous closure with VCDs (38 accesses [20%]) affected the closure success rate in the large-sheath group. Closure failure did not significantly increase the need for postoperative blood transfusions or hospital length of stay. CONCLUSIONS: Off-label use of VCDs and the preclose technique for percutaneous approach with large-bore sheaths needed for complex aortic endovascular procedures is safe and feasible. Closure success rate is not significantly different from that obtained with on-label application of VCDs with smaller sheaths.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular/instrumentación , Cateterismo Periférico/métodos , Procedimientos Endovasculares/instrumentación , Técnicas Hemostáticas/instrumentación , Dispositivos de Cierre Vascular , Anciano , Diseño de Equipo , Femenino , Arteria Femoral , Humanos , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
6.
Eur J Vasc Endovasc Surg ; 59(4): 565-576, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31870689

RESUMEN

OBJECTIVE: To evaluate the safety and effectiveness of a multistaged approach for elective thoraco-abdominal aneurysm (TAAAs) repair by means of endovascular fenestrated and/or branched (F/B-EVAR) grafts. METHODS: Between 2013 and 2018, 80 high risk surgical patients received elective F/B-EVAR for TAAAs with a protocolled multistaged approach (thoracic, visceral, and limb steps) and were enrolled in an ambispective single centre study called STEAR (STaged Endovascular Aortic Repair - NCT03342755). Data regarding all study participants, single step mortality and morbidity (systemic complications) rates were recorded and the overall results were considered for statistical analysis. RESULTS: Previous aortic interventions (61/80 cases, 76.3%) combined with the TAAA extents resulted in different staging strategies: 58 patients (73%) had a thoracic step and 33 (41%) a limb step. The median TAAA treatment time was 77 days (50-107). The overall mortality was six cases (8%) and 30 day clinical success rate 64 cases (80%). The overall rate of grade 2 or 3 (including death) systemic complications was 19 cases (24%) and 20 patients (25%) experienced grade 1 complications. Three patients with type II or III TAAAs (4%) had permanent and fatal spinal cord (SC) impairment. On multivariable analysis, SC ischaemia was associated with an aortic coverage ≥350 mm (OR: 9.15, p = .03, 95% CI: 1.3-66.4) and bovine arch (OR: 10.6, p = .01, 95% CI: 1.6-68.6). The overall short term (six month) clinical success was 72 cases (90%) and none experienced SC ischaemia after late endoleak resolution or treatment. At mid term (mean follow up: 13.3 ± 15.4 months), the overall freedom from conversions, re-interventions, late rupture, or type I and III endoleaks was 57 of 72 survivors (79%). CONCLUSION: A multistaged approach with a third limb step in case of TAAAs is safe and technically feasible, with an acceptable rate of permanent spinal cord ischaemia. Different staging methods and protocols have been proposed and standardisation is required, especially for type I-II-III aneurysms.


Asunto(s)
Aneurisma/cirugía , Aneurisma de la Aorta Torácica/cirugía , Procedimientos Endovasculares , Isquemia de la Médula Espinal/cirugía , Anciano , Anciano de 80 o más Años , Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/efectos adversos , Procedimientos Quirúrgicos Electivos/efectos adversos , Endofuga/etiología , Procedimientos Endovasculares/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Stents/efectos adversos
7.
Ann Vasc Surg ; 68: 88-92, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32589931

RESUMEN

Heparin resistance is an uncommon phenomenon defined as the need for high-dose unfractionated heparin (UFH) of more than 35,000 IU/day to achieve the target activated partial-thromboplastin time ratio or the failure to achieve the desired activated clotting time after a full UFH dose. This rare phenomenon is being more commonly observed in Covid-19 patients in a hypercoagulable state. We describe a Covid-19 patient confirmed by reverse-transcriptase polymerase chain reaction assay, with acute limb ischemia, who developed heparin resistance. The patient was managed by the departments of vascular surgery, anesthesia and intensive care, and the Coagulation Service and Thrombosis Research from San Raffaele Scientific Institute, Milan, Italy.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/complicaciones , Resistencia a Medicamentos , Heparina/farmacología , Isquemia/tratamiento farmacológico , Extremidad Inferior/irrigación sanguínea , Neumonía Viral/complicaciones , Enfermedad Aguda , Anciano , Anticoagulantes/farmacología , Coagulación Sanguínea/efectos de los fármacos , COVID-19 , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/epidemiología , Humanos , Isquemia/sangre , Isquemia/etiología , Masculino , Pandemias , Neumonía Viral/diagnóstico , Neumonía Viral/epidemiología , SARS-CoV-2 , Tomografía Computarizada por Rayos X
8.
J Vasc Surg ; 69(6): 1941-1951.e1, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30606664

RESUMEN

OBJECTIVE: The objective of this study was to collect and critically analyze the current evidence on the modalities and results of treatment of descending thoracic aortic surgical graft (SG) and endograft (EG) infection, which represents a rare but dramatic complication after both surgical and endovascular aortic repair. METHODS: A comprehensive electronic health database search (PubMed/MEDLINE, Scopus, Google Scholar, and the Cochrane Library) identified all articles that were published up to October 2017 reporting on thoracic aortic SG or EG infection. Observational studies, multicenter reports, single-center series and case reports, case-control studies, and guidelines were considered eligible if reporting specific results of treatment of descending thoracic aortic SG or EG infection. Comparisons of patients presenting with SG or EG infection and between invasive and conservative treatment were performed. Odds ratio (OR) meta-analyses were run when comparative data were available. RESULTS: Forty-three studies reporting on 233 patients with infected SG (49) or EG (184) were included. Four were multicenter studies including 107 patients, all with EG infection, associated with a fistula in 91% of cases, with a reported overall survival at 2 years of 16% to 39%. The remaining 39 single-center studies included 49 patients with SG infection and 77 with EG infection. Association with aortoesophageal fistula was significantly more common with EG (60% vs 31%; P = .01). In addition, time interval from index procedure to infection was significantly shorter with EG (17 ± 21 months vs 32 ± 61 months; P = .03). Meta-analysis showed a trend of increased 1-year mortality in patients with SG infection compared with EG infection (pooled OR, 3.6; 95% confidence interval, 0.9-14.7; P = .073). Surgical management with infected graft explantation was associated with a trend toward lower 1-year mortality compared with graft preservation (pooled OR, 0.3; 95% confidence interval, 0.1-1.0; P = .056). CONCLUSIONS: Thoracic aortic EG infection is likely to occur more frequently in association with aortoesophageal fistulas and in a shorter time compared with SG infection. Survival is poor in both groups, especially in patients with SG infection. Surgical treatment with graft explantation seems to be the preferable choice in fit patients.


Asunto(s)
Aorta Torácica/cirugía , Implantación de Prótesis Vascular/efectos adversos , Prótesis Vascular/efectos adversos , Remoción de Dispositivos , Procedimientos Endovasculares/efectos adversos , Infecciones Relacionadas con Prótesis/cirugía , Stents/efectos adversos , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Implantación de Prótesis Vascular/instrumentación , Implantación de Prótesis Vascular/mortalidad , Remoción de Dispositivos/efectos adversos , Remoción de Dispositivos/mortalidad , Procedimientos Endovasculares/instrumentación , Procedimientos Endovasculares/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Relacionadas con Prótesis/mortalidad , Reoperación , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
9.
J Vasc Surg ; 68(4): 966-975, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29606568

RESUMEN

OBJECTIVE: The aim of this study was to evaluate the perioperative and short-term results in a cohort of patients treated during the last year at our institution with the stent-assisted balloon-induced intimal disruption and relamination in aortic dissection repair (STABILISE) technique for acute complicated aortic dissection. METHODS: Between June 2016 and June 2017, 10 patients (all male; mean age, 62.6 ± 7.4 years) received treatment for acute complicated aortic dissection with the STABILISE technique. After a standard provisional extension to induce complete attachment procedure using the commercially available endovascular dissection system (Cook Medical, Bloomington, Ind), the distal stent graft area and the bare stent area were ballooned to completely exclude the thoracic false lumen (FL) and to obtain a single-channeled abdominal aorta. Computed tomography was routinely performed within the first postoperative week before discharge and then at 3 months, at 6 months, and yearly thereafter. The technical and clinical success rates were analyzed. RESULTS: The 30-day technical and clinical success rates were 100%, with complete thrombosis of the thoracic FL and no type I endoleak. Malperfusion was resolved in all cases. No aortic ruptures were recorded, and no open conversion was required. One case of delayed spinal cord ischemia fully resolved within the discharge period. Predischarge computed tomography showed complete thrombosis of the thoracic FL in all cases. In two cases, some degree of patency of the abdominal FL was observed. At short-term follow-up, the overall aortic diameters remained stable with no further dilation. CONCLUSIONS: The STABILISE technique was safe and feasible in this cohort of patients, with complete thrombosis of the thoracic FL and creation of a single-channeled aorta in most cases. Further studies are needed to ascertain the long-term behavior of the treated aorta.


Asunto(s)
Angioplastia de Balón/métodos , Aneurisma de la Aorta/cirugía , Disección Aórtica/cirugía , Implantación de Prótesis Vascular/métodos , Enfermedad Aguda , Anciano , Disección Aórtica/diagnóstico por imagen , Disección Aórtica/fisiopatología , Angioplastia de Balón/efectos adversos , Angioplastia de Balón/instrumentación , Aneurisma de la Aorta/diagnóstico por imagen , Aneurisma de la Aorta/fisiopatología , Aortografía/métodos , Prótesis Vascular , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/instrumentación , Angiografía por Tomografía Computarizada , Ecocardiografía Transesofágica , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Stents , Factores de Tiempo , Resultado del Tratamiento
10.
J Endovasc Ther ; 25(2): 230-236, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29313455

RESUMEN

PURPOSE: To evaluate the 1-year outcomes of thoracoabdominal aortic aneurysm (TAAA) repair using fenestrated and branched stent-grafts and a novel balloon-expandable covered stent. METHODS: Between March 2015 and January 2017, 18 patients (median age 74.7 years; 14 men) received 43 LifeStream balloon-expandable covered stents in conjunction with Zenith fenestrated/branched stent-grafts to bridge 11 celiac trunks, 8 superior mesenteric arteries, and 24 renal arteries (total 32 fenestrations and 11 branches). RESULTS: Stent delivery and deployment was successful in all cases. At 30 days, 5 patients presented with perifenestration endoleaks (type IIIc) secondary to inadequate sealing of the LifeStream covered stent in 7 (22%) of 32 fenestrations. No type IIIc endoleaks were reported in the branched cases. Four patients had a secondary endovascular reintervention with proximal relining by means of a bare balloon-expandable stent at the perifenestration transition area, with complete resolution of the endoleak at 1-year follow-up. One patient refused reintervention. The last 4 fenestrated stent-grafts of this series had prophylactic perifenestration bare stent relining with no evidence of type IIIc endoleaks at imaging. At a median follow-up of 14.1 months (interquartile range 11, 22), the 12-month LifeStream patency rate was 100%. CONCLUSION: This single-center preliminary experience with the LifeStream balloon-expandable covered stent in fenestrated/branched stent-grafts for TAAA repairs demonstrated good patency; however, an unexpectedly high rate of type IIIc endoleaks was observed. These endoleaks were resolved with reintervention or during the index procedure by proximal relining with a bare balloon-expandable stent, achieving adequate perifenestration sealing.


Asunto(s)
Angioplastia de Balón/instrumentación , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Stents , Anciano , Angioplastia de Balón/efectos adversos , Angioplastia de Balón/mortalidad , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/mortalidad , Aneurisma de la Aorta Torácica/fisiopatología , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/mortalidad , Endofuga/etiología , Endofuga/terapia , Femenino , Humanos , Masculino , Datos Preliminares , Diseño de Prótesis , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Grado de Desobstrucción Vascular
11.
J Vasc Surg ; 66(4): 1065-1072, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28478020

RESUMEN

OBJECTIVE: The aim of this study was to evaluate midterm clinical and morphologic outcomes after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm (AAA) with large (≥28 mm) infrarenal neck. METHODS: From 2009 to 2012, we prospectively collected and retrospectively analyzed clinical, morphologic, and intraoperative and postoperative data of patients undergoing EVAR for wide-neck AAA at three European vascular surgery units. All patients had computed tomography angiography follow-up of ≥24 months. The early end points were technical success and proximal type I endoleak at 30 days. The midterm end points were type Ia endoleak, freedom from reintervention (FFR), survival, AAA-related mortality, and infrarenal and suprarenal aortic diameter progression. The aortic diameters were measured on three-dimensional workstation center lumen line reconstructions, 1 cm below the lowest renal artery, at the level of the renal arteries, at the superior mesenteric artery, and at the celiac trunk. Preoperative and 24-month aortic diameters were compared by paired t-test. Survival and FFR were evaluated by Kaplan-Meier analysis. RESULTS: During the study period, 118 patients (74 ± 8 years) were enrolled. The mean aneurysm diameter was 61 ± 10 mm. Suprarenal and infrarenal fixation endografts were implanted in 102 (86%) and 16 (14%) patients, respectively. The mean main body oversizing was 17% ± 9%. Technical success rate was 98% (three type Ia endoleaks at 30 days). The mean follow-up was 38 ± 12 months. Fourteen type Ia endoleaks (12%) were detected during follow-up. Survival at 3 years and 5 years was 89% and 70%, respectively. Four deaths (3.4%) were type Ia endoleak related. FFR at 1 year, 3 years, and 5 years was 96%, 83%, and 82%, respectively. Eight reinterventions (7%) were proximal neck related. All infrarenal and suprarenal aortic diameters increased at 24 months. The mean increase was 11% for the lowest renal artery (29.1 ± 1.1 mm preoperatively vs 32.3 ± 4.5 mm at 24 months; P < .001), 3% to 5% at the level of the renal arteries, and <3% for the superior mesenteric artery and the celiac trunk. Neck length <15 mm (P = .032), stainless steel endograft (P = .003), and type Ia endoleak at 24 months (P = .001) were associated with infrarenal neck enlargement on multivariate logistic regression. CONCLUSIONS: EVAR performed in AAAs with large necks is associated with a significant infrarenal aortic neck enlargement at 24 months as well as with a high risk of proximal type I endoleak and proximal neck-related reinterventions. In this subgroup of patients, main body oversizing >15% and suprarenal sealing should be considered.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/mortalidad , Aortografía/métodos , Prótesis Vascular , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/instrumentación , Implantación de Prótesis Vascular/mortalidad , Angiografía por Tomografía Computarizada , Supervivencia sin Enfermedad , Endofuga/etiología , Endofuga/terapia , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/instrumentación , Procedimientos Endovasculares/mortalidad , Femenino , Francia , Humanos , Italia , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Sistema de Registros , Retratamiento , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
12.
J Vasc Surg ; 65(2): 318-329, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27832988

RESUMEN

OBJECTIVE: Long-term results of abdominal aortic aneurysm (AAA) endovascular repair are affected by graft design renewals that tend to improve the performance of older generation prostheses but usually reset the follow-up times to zero. The present study investigated the long-term outcomes of endovascular AAA repair (EVAR) using the Zenith graft, still in use without major modification, in a single center experience. METHODS: Between 2000 and 2011, 610 patients underwent elective EVAR using the Zenith endograft (Cook Inc, Bloomington, Ind) and represent the study group. Primary outcomes were overall survival, freedom from AAA rupture, and freedom from AAA-related death. Secondary outcomes included freedom from late (>30 days) reintervention, freedom from late (>30 days) conversion to open repair, freedom from aneurysm sac enlargement >5.0 mm and freedom from EVAR failure, defined as a composite of AAA-related death, AAA rupture, AAA growth >5 mm, and any reintervention. RESULTS: Mean age was 73.2 years. Mean aneurysm diameter was 55.3 mm. There were five perioperative deaths (0.8%) and three intraoperative conversions. At a mean follow-up of 99.2 (range, 0-175) months, seven AAA ruptures occurred, all fatal except one. Overall survival was 92.8% ± 1.1% at 1 year, 70.1% ± 1.9% at 5 years, 37.8% ± 2.9% at 10 years, and 24 ± 4% at 14 years. Freedom from AAA-rupture was 99.8% ± 0.02 at 1 year (one case), 99.4% ± 0.04 at 5 years (three cases), and 98.1% ± 0.07 at 10 and 14 years. Freedom from late reintervention and conversion was 98% ± 0.6 at 1 year, 87.7% ± 1.5 at 5 years, 75.7% ± 3.2 at 10 years, and 69.9% ± 5.2 at 14 years. Freedom from aneurysm sac growth >5.0 mm was 99.8% at 1 year, 96.6% ± 0.7 at 5 years, 81.0% ± 3.4 at 10 years, and 74.1% ± 5.8% at 14 years. EVAR failure occurred in 132 (21.6%) patients at 14 years. At multivariate analysis, independent predictors of EVAR failure resulted type I and III endoleak (hazard ratio [HR], 6.7; 95% confidence interval [CI], 4.6- 9.7; P < .001], type II endoleak (HR, 2.3; 95% CI, 1.6-3.4; P < .001), and American Society of Anesthesiologists grade 4 (HR, 1.6; 95% CI, 1.0-2.6; P = .034). CONCLUSIONS: EVAR with Zenith graft represents a safe and durable repair. Risk of rupture and aneurysm-related death is low, whereas overall long-term survival remains poor. Novel endograft models should be tested and evaluated considering that one-fourth of the operated patients will still be alive after 14 years.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/instrumentación , Stents , Adulto , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Abdominal/complicaciones , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/mortalidad , Rotura de la Aorta/etiología , Rotura de la Aorta/mortalidad , Rotura de la Aorta/terapia , Aortografía/métodos , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/mortalidad , Distribución de Chi-Cuadrado , Angiografía por Tomografía Computarizada , Bases de Datos Factuales , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Endofuga/etiología , Endofuga/mortalidad , Endofuga/terapia , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/mortalidad , Femenino , Oclusión de Injerto Vascular/etiología , Oclusión de Injerto Vascular/mortalidad , Oclusión de Injerto Vascular/terapia , Humanos , Italia , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Modelos de Riesgos Proporcionales , Diseño de Prótesis , Retratamiento , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
15.
J Endovasc Ther ; 21(3): 439-47, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24915595

RESUMEN

PURPOSE: To evaluate the late results of endovascular aneurysm repair (EVAR) with the endografts currently in use and compare outcomes to older devices. METHODS: Clinical, demographic, and imaging data on consecutive patients undergoing elective EVAR from January 1997 to December 2011 at a single center were retrieved from an electronic database and reviewed. Newer stent-grafts (NSG) were defined as those introduced after 2004 (second-generation Excluder and Anaconda) or currently in use without modifications (Zenith, Endurant). Of the 1412 consecutive patients (1290 men; mean age 73 years) who underwent elective EVAR in a tertiary university hospital, 882 were treated with NSGs and 530 with older stent-grafts (OSGs). RESULTS: In the NSG group, the abdominal aortic aneurysms (AAA) were larger (55.7 vs. 53.2 mm, p<0.0001) and the patients were older (p<0.0001) and less frequently smokers or had pulmonary disease, while hypertension and diabetes were more frequent (all p<0.0001). Thirty-day mortality was 0.8% in the NSG group vs. 1.1% in the OSG group (p=NS). Follow-up ranged from 1 to 174 months (mean 54.1±42.4); the OSG patients had longer mean follow-up compared to the NSG group (80.2±47.9 vs. 38.4±29.1 months, p<0.0001). All-cause survival rates were comparable in both groups. Freedom from late conversion (96.1% vs. 89.1% at 7 years, p<0.0001) or reintervention (83.6% vs. 74.2% at 7 years, p=0.015) and freedom from AAA diameter growth >5 mm (p=0.022) were higher in the NSG group. In adjusted analyses, the use of a new-generation device was a negative independent predictor of reintervention [hazard ratio (HR) 0.67, 95% confidence interval (CI) 0.49 to 0.93, p=0.015] and aneurysm growth (HR 0.63, 95% CI 0.45 to 0.89, p=0.010). CONCLUSION: Newer-generation endografts can perform substantially better than the older devices. In the long term, incidences of reintervention, conversion, and AAA growth are decreased in patients treated with devices currently in use. However, the need for continuous surveillance is still imperative for all endografts.


Asunto(s)
Aorta Abdominal/cirugía , Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/instrumentación , Diseño de Prótesis , Stents , Anciano , Anciano de 80 o más Años , Aorta Abdominal/fisiopatología , Aneurisma de la Aorta Abdominal/diagnóstico , Aneurisma de la Aorta Abdominal/mortalidad , Aneurisma de la Aorta Abdominal/fisiopatología , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/mortalidad , Supervivencia sin Enfermedad , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/mortalidad , Femenino , Hospitales Universitarios , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/mortalidad , Complicaciones Posoperatorias/cirugía , Modelos de Riesgos Proporcionales , Reoperación , Estudios Retrospectivos , Factores de Riesgo , Ciudad de Roma , Centros de Atención Terciaria , Factores de Tiempo , Resultado del Tratamiento
16.
Int Angiol ; 42(3): 223-228, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37222507

RESUMEN

INTRODUCTION: To perform a scoping review analyzing the current evidence reporting on acute kidney injury (AKI) after elective open surgery (OS) of complex abdominal aortic aneurysms (c-AAAs) and evaluate the impact of renal perfusion, and the different types of solutions on renal morbidity. EVIDENCE ACQUISITION: Research questions were defined, and a literature search was performed following the PRISMA guidelines for scoping reviews. Multicenter, single-center observational studies were considered eligible. No abstracts only and unpublished literature were included. EVIDENCE SYNTHESIS: Two hundred and fifty studies were screened, 20 studies met screening criteria and were included, reporting 1552 patients treated for c-AAAs. The majority did not receive renal perfusion and the others received different types of renal perfusions. Acute kidney injury is a common complication after c-AAAs OS, with an incidence up to 32.5%. Heterogeneity in AKI classifications reduce the ability to compare outcomes after perfusion and nonperfusion strategies. Pre-existing CKD, ischemic injury due to suprarenal aortic clamping are major determinants of AKI after aortic surgery. Most papers reported chronic kidney disease (CKD) at admission. Another debated topic is the indication for renal perfusion during c-AAAs OS. Controversial results for cold renal perfusion have been found. CONCLUSIONS: In the context of c-AAAs, this review identified the need to standardize the definition of AKI to reduce reporting bias. Besides this, it showed the need to assess the indication for renal perfusion and the type of perfusion solution to be used.


Asunto(s)
Lesión Renal Aguda , Aneurisma de la Aorta Abdominal , Insuficiencia Renal Crónica , Humanos , Lesión Renal Aguda/etiología , Aorta Abdominal , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/cirugía , Estudios Multicéntricos como Asunto , Perfusión/efectos adversos , Insuficiencia Renal Crónica/diagnóstico
17.
J Cardiovasc Surg (Torino) ; 64(5): 459-469, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37199677

RESUMEN

INTRODUCTION: The aim of the present study is to perform a systematic review of published papers regarding the suitability of the current off-the-shelf (OTS) devices for endovascular thoracoabdominal aortic aneurysm (TAAA) repair. EVIDENCE ACQUISITION: A systematic review of the MEDLINE database via PubMed was performed in March 2023. All studies reporting the outcomes of the three currently available OTS stent-grafts: the Zenith t-Branch (Cook Medical, Bloomington, IN, USA), the Gore Excluder thoracoabdominal branch endoprosthesis (TAMBE; W.L. Gore & Associates, Flagstaff, AZ, USA) and the E-nside Multibranch Stent-Graft System (Artivion, Kennesaw, GA, USA), were retrieved and further analyzed. The main endpoints were technical success, reintervention rate, and primary branch patency. Theoretical feasibility studies of these OTS devices were also included and separately analyzed. EVIDENCE SYNTHESIS: A total of 19 studies were published between 2014 and 2023. Thirteen clinical studies and six theoretical feasibility studies were included. Eleven studies reported the clinical outcomes of the t-Branch stent-graft, one detailed the observational results of the use of the E-nside endoprosthesis, and one described the TAMBE stent-graft results. The following data primarily involve the t-Branch device outcomes. A total of 1131 patients that underwent aneurysm repair using an OTS stent-graft were identified. Among those, 1002, 116 and 13 patients received a t-Branch, E-nside, and TAMBE stent-grafts, respectively. A total of 767 (67.8%) were men, with a mean age of 71.6±7.4 years old, and a mean Body Mass Index (BMI) of 26.3±3.8 kg/m2. Technical success ranged from 64% to 100%. A total of 4172 target visceral vessels (TVV) were planned for bridging, with a success rate ranging from 92 to 100%. The total of early and late reinterventions reported were 64 and 48, respectively, mainly due to endoleaks and visceral branch occlusions. Among the theoretical feasibility studies, six described the feasibility of the t-Branch device in a total of 661 patients, two described the E-nside and the TAMBE devices feasibility comprising 351 patients for each stent-graft. The overall feasibility of the t-Branch device varied from 39% to 88%, the E-nside from 43% to 75%, and the TAMBE stent-graft ranged from 33% to 94%. CONCLUSIONS: This systematic review demonstrated a good suitability for the use of OTS endografts for the treatment of TAAA.

18.
Int Angiol ; 42(5): 402-411, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37943291

RESUMEN

BACKGROUND: The aim of this study was to assess perioperative and late performance of a silver acetate and triclosan impregnated antimicrobial vascular graft (Intergard Synergy, Intervascular SAS, La Ciotat, France) during open surgical repair of abdominal aortic aneurysms (AAA), and to compare it with standard polyester grafts ones. METHODS: This retrospective single-centre study (STAGER Study, clinicaltrials.gov: NCT04557254) included patients undergone non-infectious AAA surgical repair between 2012 and 2019, divided into two groups according to the implanted aortic prosthesis: standard polyester graft (PolyG) and silver-triclosan graft (SynG). Early primary endpoints were 30-day mortality, major adverse events (MAEs), and reintervention rates; late primary endpoints were overall and aortic-related survival, reintervention-free survival, and graft infection rate at a mean follow-up (FU) of 49.4±26.8 months. RESULTS: Five hundred forty-seven patients were included [PolyG 49%, and SynG 51%]. Both groups were substantially homogeneous in risk factors and demographics. Two patients died within 30 days. In-hospital MAE rate [PolyG 14.2% vs. SynG 10.7%; P=.248] and 30-day reintervention rate were not significantly different [PolyG 2.6% vs. SynG 1.4%; P=.374]. At 5 years, overall survival in the PolyG and SynG groups were 85% and 84%, respectively. Reintervention-free survival was 82% for both groups. Aortic-related survival was 95% and 96%, respectively. Graft infection was observed in 8 (3.3%) PolyG patients and 5 (1.8%) SynG patients. CONCLUSIONS: Silver acetate and triclosan impregnated grafts demonstrated good early and mid-term results, being considered safe and durable for AAA open repair. Similar graft infection and related death rates were observed compared to polyester standard grafts, supporting non-superiority of one graft over the other.


Asunto(s)
Antiinfecciosos , Aneurisma de la Aorta Abdominal , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Triclosán , Humanos , Triclosán/efectos adversos , Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/métodos , Estudios Retrospectivos , Complicaciones Posoperatorias/etiología , Aneurisma de la Aorta Abdominal/cirugía , Poliésteres , Resultado del Tratamiento , Factores de Riesgo
19.
Aorta (Stamford) ; 10(4): 194-200, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36521813

RESUMEN

Despite the improvements, spinal cord ischemia is still one of the major and most dramatic potential complications after thoracic and thoracoabdominal aortic treatments, for both open and endovascular procedures. A multimodal approach, which includes several intraoperative and postoperative maneuvers, may contribute to optimizing the spinal cord tolerance to ischemia. The aim of this article is to report the different techniques employed to improve spinal cord perfusion, directly and indirectly through collateral circulation.

20.
J Cardiovasc Surg (Torino) ; 62(4): 326-338, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33307647

RESUMEN

Acute kidney injury (AKI) is a common complication of both open and endovascular repair of thoracoabdominal aortic aneurysms (TAAA). Its definition varies across difference studies, some standardized definitions (RIFLE, AKIN, KDIGO) have been proposed but still not uniformly employed in published papers. Acute kidney injury is multifactorial and is associated with increased in-hospital mortality, long-term mortality and late renal function decline. In addition, AKI is also associated with perioperative spinal cord ischemia. No specific pharmacological strategy has received a strong recommendation with high level of evidence as a protective measure. Fenoldopam, methylprednisolone or mannitol use to prevent AKI is commonly employed, but not supported by literature data. Avoiding nephrotoxic drugs and maintaining an adequate MAP, during and after the procedure plays a key role in preserving kidney function. During open TAAA surgery, renal arteries may be reimplanted using different techniques. The choice of the best option must be tailored to the patient, to reduce ischemic time and guarantee long-term patency. Current experience suggests that cold crystalloid solutions are the best substrates in preventing ischemia-reperfusion injury. Renal perfusion using Custodiol® (Dr Franz-Kohler Chemie GmbH; Bensheim, Germany) 4 °C, even if currently considered off-label, represents an encouraging organ protection tool. In endovascular TAAA repair, techniques such as fusion imaging, use of diluted contrast, and CO2 subtraction angiography have the potential to reduce postoperative AKI. Visceral vessels patency is closely related to the anatomy. Therefore, accurate endograft design according to these characteristics is crucial for long-term preservation of renal function.


Asunto(s)
Lesión Renal Aguda/prevención & control , Aneurisma de la Aorta Torácica/cirugía , Procedimientos Endovasculares/métodos , Lesión Renal Aguda/etiología , Aneurisma de la Aorta Torácica/complicaciones , Humanos , Resultado del Tratamiento
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA