Intravascular Ultrasound Assessment and Correlation With Angiographic Findings Demonstrating Femoropopliteal Arterial Dissections Post Atherectomy: Results From the iDissection Study.

BACKGROUND: Dissections occur post atherectomy of the infrainguinal arteries. We hypothesized that angiography under-estimates their presence significantly. METHODS: In this prospective pilot study, a total of 15 patients were evaluated by intravascular ultrasound (IVUS) following treatment of femoropopliteal de novo or non-stent restenosis using atherectomy. Eagle Eye Platinum ST IVUS catheters (Philips) were used in this study. Thirteen Jetstream XC atherectomy devices (Boston Scientific) and 2 investigational B-laser atherectomy devices (Eximo Medical) were used. Cine and IVUS images were obtained at baseline, after atherectomy, and after adjunctive balloon angioplasty. Angiographic and IVUS core labs analyzed the images. RESULTS: Mean age was 70.6 ± 8.0 years. Diabetes and claudication were present in 60% and 73%, respectively. Mean baseline, post-atherectomy, and post-adjunctive angioplasty stenosis severity was 71.4%, 38.1%, and 19.7%, respectively (P<.001 for both baseline vs post atherectomy and post atherectomy vs adjunctive angioplasty). Lesion length was 108.5 ± 43.1 mm. Forty-six dissections were identified on IVUS post atherectomy vs 8 dissections on angiogram (P<.01) (ratio, 5.75 to 1). Post adjunctive angioplasty, there were 39 dissections on IVUS vs 11 on angiogram (P<.01) (ratio, 3.55 to 1). Of these dissections, 13% and 30.8% were ≥180° in circumference post atherectomy and adjunctive balloon angioplasty, respectively (P=.047). Also, 39.1% and 33.3% involved the media and/or adventitia as seen on IVUS post atherectomy and adjunctive balloon angioplasty, respectively (P=.58). Longer lesions correlated with more dissections post atherectomy on IVUS (P=.03), but not on angiogram (P=.28). CONCLUSION: Dissections post atherectomy are grossly under-appreciated on angiogram when compared to IVUS. A multicenter registry correlating these findings with clinical outcomes is needed.

Intravascular ultrasound assessment of the effect of laser energy on the arterial wall during the treatment of femoro-popliteal lesions: a CliRpath excimer laser system to enlarge lumen openings (CELLO) registry study.

The CliRpath Excimer Laser System to Enlarge Lumen Openings (CELLO) registry included patients treated with modified excimer laser catheters for the endovascular treatment of peripheral artery disease affecting the superficial femoral artery (SFA) and proximal popliteal artery. The aim of this study was to assess, via intravascular ultrasound (IVUS) the dissections in the vessel wall following treatment with the laser catheters. IVUS grayscale images from the CELLO registry were systematically reviewed for dissections in the treated vessel segments by two investigators. Images from 33 patients; 66 pullbacks (1867 IVUS frames in 2 phases), were successfully matched frame-to-frame to evaluate identical segments of the treated vessels in the two phases; post-2 mm Turbo-Elite laser pilot channel creation and post Turbo-Booster laser atherectomy. Dissections were categorized as; (1) intimal, (2) medial, (3) intramural hematoma, and (4) adventitial according to the ACC Clinical Expert Consensus Document classification of dissections. An average of 57 frames was evaluated per pullback, giving a total of 3734 frames (1867 matched for pre-ablation (post channel creation) and post-ablation phases). Treatments with the modified Excimer laser catheters resulted in a significant increase in lumen area of 5.5 ± 3.2-mm2 (95% CI 4.3-6.8, p < 0.0001) and reduction in plaque plus media volume of -10.6 ± 36.0 mm3 (95% CI -25.8 to 4.6, p = 0.1619) whilst giving rise to mainly intramural hematoma formations post Turbo-Booster laser treatment in 55% of frames assessed and 24% medial dissections with less than 1% adventitial disruption. The Excimer laser based Turbo-Booster treatment of peripheral artery lesions resulted in significant plaque debulking and increased lumen diameter with negligible degree of adventitial layer injury.

Transfemoral access assessment for transcatheter aortic valve replacement: evidence-based application of computed tomography over invasive angiography.

BACKGROUND: Although computed tomography (CT) is commonly used for iliofemoral evaluation for transfemoral transcatheter aortic valve replacement, many centers worldwide use invasive angiography alone for this purpose. No study to date has evaluated the value of CT over angiography for the prediction of vascular complications. In addition, no data exist for the value of noncontrast CT. METHODS AND RESULTS: Of the 588 transcatheter aortic valve replacement patients, we reviewed 496 consecutive transfemoral cases. Vessel diameters were measured by CT or angiography. Sheath-related complication (SRC) was defined as an iliofemoral arterial injury not including a cannulation site. Receiver operating characteristic models were generated using sheath-to-iliofemoral artery ratios as a variable and SRC as an end point. In patients undergoing both contrast CT and angiography (n=283; 35 SRCs), contrast CT showed a greater predictive value than angiography by area under the curve P<0.001): 0.87 (95% confidence interval: 0.82-0.91) versus 0.72 (95% confidence interval: 0.66-0.77). In patients undergoing both noncontrast CT and angiography (n=103; 17 SRCs), there was no difference between noncontrast CT and angiography: 0.79 (95% confidence interval: 0.70-0.86) versus 0.73 (95% confidence interval: 0.63-0.81). Three-dimensional assessments of calcification and tortuosity provided limited additional value for SRC prediction. CONCLUSIONS: Contrast CT has a greater predictive value for post-transcatheter aortic valve replacement vascular complications than angiography. Because these complications increase mortality, an accurate assessment of the vasculature is a critical component of proper access selection.

Tratamiento endovascular de lesiones de arteria femoral superficial, TASC II B-C mediante stents de nitinol autoexpandibles extra largos (> 120 mm). Evaluación de la permeabilidad a los 6, 12, 24 y 36 meses post implante. / Tratamento endovascular de lesões da artéria femoral superficial, TASC II B-C com o uso de stents de nitinol auto-expansíveis extra longos (> 120mm). Avaliação da permeabilidade após 6, 12, 24 e 36 meses pós implante. / Endovascular treatment of TASC II B-C lesions of the superficial femoral artery with ultra long self expandable nitinol stents (> 120 mm). Assessment of patency at 6, 12, 24 and 36 months post-stenting

Objetivos: evaluación de la permeabilidad de los stents de Nitinol autoexpandibles extra largos(> 120 mm de longitud) en lesiones de arteria femoral superficial TASC II B-C, a los 6, 12, 24 y 36 meses post implante.Pacientes y Métodos: Entre junio de 2007 y diciembre de 2008, fueron tratados 7 miembros inferiores en 6 pacientes con lesiones de arteria femoral superficial tipo TASC II B-C mediante stents extra largos auto expandibles. Utilizamos stents autoexpandibles de Nitinol de 120-140 mm largo (Large SMART CONTROL) (Cordis). Utilizamos la vía percutánea ipsilateral anterógrada y, en aquellos pacientes que presentaron enfermedad de la cámara femoral, realizamos tratamiento hibrido: endarterectomía femoral, angioplastia con balón y colocación de stent. Se realizó elseguimiento mediante Ecodoppler y Rx de miembro inferior a los 6, 12, 24 y 36 meses post implante. Resultados: Se intervino a 5 pacientes del sexo femenino (84%) con un promedio de edad de 74 años +/- 5; 1 paciente de sexo masculino (16%) cuya edad fue de 60 años. 3 procedimientos fueron por vía percutánea ipsilateral anterógrada. Se realizaron 4 procedimientos híbridos (endarterectomía cámara femoral, angioplastia con balón y colocación de stent). La permeabilidad inicial fue del 100%, permeabilidad a los 6 meses: 100% de los casos, permeabilidad a los 12 meses: 86% de los casos, permeabilidad a los 24 meses: 86% de los casos con detección de Reestenosisen una paciente del 60%, siendo asintomática, permeabilidad a los 36 meses: 72 % de los casos. No se observaron fracturas de stent durante el estudio. Conclusiones: El stent largo de (> 120 mm longitud) es un buen instrumento para el tratamientode lesiones tipo TASC II B-C, comparables con la cirugía convencional, los cirujanos vascularesdeben conocer y aplicar todas las técnicas disponibles (cirugía, bioingeniería, endovascular, etc.) al tratar enfermedad arterial periférica encontrando la mejor opción para cada paciente...

Objetivo: avaliaçãó da permeabilidade dos stents de Nitinol auto expansíveis extra longos (> 120 mm de longitude) em lesões da artéria femoral superficial TASC II B-C, após 6, 12, 24 e 36 mesespós implante. Pacientes e Métodos: Entre junho de 2007 e dezembro de 2008, foram tratados 7 membrosinferiores em 6 pacientes com lesões da artéria femoral superficial tipo TASC II B-C com o uso de stents extra longos auto expansíveis. Utilizamos stents auto expansíveis de Nitinol de 120-140mm de comprimento (Large SMART CONTROL) (Cordis). Utilizamos a via percutânea ipsilateral anterógrada e, nos pacientes que apresentaram problemas na câmara femoral, realizamos um tratamento híbrido: endarterectomia femoral, angioplastia com balão e colocação de stent. Oseguimento foi realizado com a utilização de Ecodoppler e Rx de membro inferior após 6, 12, 24 e 36 meses pós implante. Resultados: Dos pacientes tratados, 5 eram do sexo feminino (84%) com uma média de idade de 74 anos +/- 5; 1 paciente do sexo masculino (16%) de 60 anos de idade. Com relação aos procedimentos, 3 foram por via percutãnea ipsilateral anterógrada. Foram realizados 4 procedimentos híbridos (endarterectomia câmara femoral, angioplastia com balão e colocação de stent). A permeabilidade inicial foi de 100%, após 6 meses, também de 100%, após 12 meses a permeabilidadefoi de 86% e 24 meses depois, de 86% com detecção de Reestenosis em uma paciente em 60%, sendo assintomática,apresentando uma permeabilidade após 36 meses de 72%. Não foram observadas fraturas de stent durante o estudo realizado. Conclusões: O stent longo de (> 120 mm de comp.) é um bom instrumento para o tratamentode lesões tipo TASC II B-C, comparáveis com a cirurgia convencional, os cirurgiões vasculares devem conhecer e aplicar todas as técnicas disponíveis (cirurgia, bioengenharia, endovascular, etc.) no tratamento da doença arterial periférica, encontrando a melhor opção para cada paciente...

Objetives: Evaluation of self-expanding large nitinol (> 120mm) stents patency in the treatments of TASC II B-C of SFA lesions at 6, 12 , 24 and 36 months after implantation. Patients and Methods: Between June 2007 to December 2008, we have treated 7 legs in 6 patients with TASC II B-C of Superficial Femoral Artery lesions with large nitinol stent, SMART (Cordis). The procedures was with percutaneous ipsilateral antegrade approach and when the patients had femoral common disease had made hybrid approach (open femoral endarterectomy+ balloon angioplasty & stent placement). We used nitinol stents of 120-140 mm large (Large SMART CONTROL) ( Cordis). The follow-up of patency was studied with Dupplex Scan and RX of the legs at 6, 12, 24 and 36 months after the initial treatment.Results: 5 ( five) Female patients (84%) mean age 74 years +/- 5; 1 (one) Male patient (16%) mean age 60 years. 3 procedures was with percutaneous ipsilateral antegrade approach. 4 was hybrid approach ( open femoral endarterectomy + balloon angioplasty & stent placement). Initial patency was of 100%, Restenosis in one case (14%) of 60% asintomatyc patient at 24 months and distal to stent placement; Ocluded one case (14%) at 12 month (man with reestenosiscarotid stent to). Don´t observed stent fracture in this study. Conclusions: Large Nitinol stents (> 120 mm length) are a good instrument to the treatment of superficial artery lesion with a comparable patency with surgery approach in lesions TASC II B-C. Vascular Surgeons needs to learn and use all of the technics (conventional surgery, Bio Ingeneering, Endovascular) to treat periphereal arterial disease and found the best options for each patients...

Development of a standard swine hemorrhage model for efficacy assessment of topical hemostatic agents.

BACKGROUND: The diverse information of efficacy of hemostatic products, obtained from different military laboratories using different models, has made it difficult to ascertain the true benefit of new hemostatic agents in military medicine. The aim of this study was to recommend a standard hemorrhage model for efficacy testing acceptable by most investigators in the field and avoid contradictory and duplicative efforts by different laboratories. METHODS: The swine femoral artery injury model (6-mm arteriotomy) with some modifications was tested to standardize the model. The suggested modifications included no splenectomy, one-time treatment, 30 seconds free bleeding, and 5 L limit for fluid resuscitation. The model was tested with all or some of these modifications in four experimental conditions (n = 5-6 pigs per condition) using Combat Gauze (CG) as control agent. RESULTS: The primary end points including blood pressure, blood loss, and survival rates were modestly changed in the four conditions. The second experimental condition in which bleeding was treated with a single CG with 3-minute compression produced the most suitable results. The average blood loss was 99 mL/kg, and hemostasis was achieved in one-third of the pigs, which led to matching survival rate. CONCLUSION: A rigorous hemorrhage model was developed for future evaluation of new hemostatic agents and comparison with CG, the current standard of care. This model may not be suitable for testing every agent and some modifications may be necessary for specific applications. Furthermore, laboratory studies using this or similar models must be accompanied by operational testing in the field to confirm the efficacy and practical utility of selected agents when used on the battlefield.

Incremental role of three-dimensional over two-dimensional ultrasound in the assessment of traumatic peripheral arteriovenous fistula.

We present a patient with an accidental self-inflicted stab wound to his right thigh in whom three-dimensional (3D) ultrasound was able to find two communications between the right femoral artery and the femoral vein, in contrast to two-dimensional (2D) peripheral ultrasound which could find only one communication between them, thereby showing an incremental value of 3D over 2D ultrasound.

Assessment of mouse hind limb endothelial function by measuring femoral artery blood flow responses.

OBJECTIVE: Substantial progress has been made in cell therapy strategies and in gene- and cytokine-introduced angiogenesis using a variety of mouse models, such as hind limb ischemia models. Endothelial function is an important target in evaluating the effects and outcomes of these potential therapies. Although animal models have been established for estimating endothelium-dependent function by measuring the blood flow responses in carotid and renal arteries and the abdominal aorta, a model specific for an indicated hind limb by measuring femoral artery blood flow (FABF) has not yet been established. METHODS: A 2-day protocol was designed, including exploration of the segmental femoral artery on the first day, and evaluation of endothelium-dependent vasodilatation function the next day. By placing a transonic flow probe around the left femoral artery, the FABF in response to endothelium-dependent and endothelium-independent vasodilatory stimulations was reproducibly measured. Hemodynamic measurements, including the left FABF and mean arterial pressure, were recorded. RESULTS: In normal controls, the baseline left FABF averaged 0.12 ± 0.01 mL/min. Acetylcholine increased the FABF up to 0.41 ± 0.02 mL/min. Rose bengal-associated photochemical injury was titrated to cause endothelial dysfunction but without disturbing the integrity of the endothelial layer. The response to acetylcholine significantly decreased 10 minutes after photochemical injury and was further impaired after 1 and 24 hours. However, the response to nitroprusside was preserved. A femoral and iliac artery wire-injury model was also introduced to cause endothelial and smooth muscle cell injury. One day after the wire injury, the responses to acetylcholine and nitroprusside injections were both remarkably attenuated. CONCLUSIONS: This model can be widely used to analyze the in vivo endothelium-dependent vasodilatation function before and after a variety of therapeutic interventions on a mouse hind limb.

ARFI ultrasound for in vivo hemostasis assessment postcardiac catheterization, part I: preclinical studies.

The world wide prevalence of cardiovascular disease leads to over seven million annual percutaneous coronary catheterization procedures, the majority of which exploit femoral artery access. Femoral puncture sites ('arteriotomies') can be associated with severe vessel complications after sheath removal if hemostasis is not properly achieved. Hemostasis onset is routinely determined by examination for bleeding at the skin puncture; however, clotting along the puncture path can obscure subcutaneous bleeding, and therefore hemostasis is blindly assessed. We hypothesize that hemostasis assessment can be un-blinded by Acoustic Radiation Force Impulse (ARFI) ultrasound. In this first of a two-part series, we present in vivo ARFI hemostasis imaging data obtained in relevant canine models of femoral artery puncture. Above arteriotomies, ARFI-induced displacements were large (3.5 to >5.0 microm) relative to surrounding soft tissue soon after needle removal, which was consistent with our expectation for pooled extravasated blood. ARFI-induced displacements above arteriotomies decreased in magnitude (to approximately 2 microm) some time after needle removal and suggested the onset of hemostasis. This preclinical investigation served as proof of concept and justification for a pilot human study, which is presented in part two of this series.

ARFI ultrasound for in vivo hemostasis assessment postcardiac catheterization, part II: pilot clinical results.

In this second of a two part series, we present pilot clinical data demonstrating Acoustic Radiation Force Impulse (ARFI) ultrasound for monitoring the onset of subcutaneous hemostasis at femoral artery puncture sites (arteriotomies), in vivo. We conducted a randomized, reader-blinded investigation of 20 patient volunteers who underwent diagnostic percutaneous coronary catheterization. After sheath removal (6 French), patients were randomized to treatment with either standard of care manual compression alone or, to expedite hemostasis, manual compression augmented with a p-GlcNAc fiber-based hemostatic dressing (Marine Polymer Technologies, Danvers MA). Concurrent with manual compression, serial ARFI imaging began at the time of sheath removal and continued every minute for 15 min. Serial data sets were processed with custom software to (1) estimate the time of hemostasis onset, and (2) render hybrid ARFI/B-Mode images to highlight displacements considered to correspond to extravasted blood. Images were read by an observer blinded to the treatment groups. Average estimated times to hemostasis in patient volunteers treated with manual compression alone (n = 10) and manual compression augmented by hemostatic dressing (n = 9) were, respectively, 13.00 +/- 1.56 and 9.44 +/- 3.09 min, which are statistically significantly different (p = 0.0065, Wilcoxon two-sample test). Example images are shown for three selected patient volunteers. These pilot data suggest that ARFI ultrasound is relevant to monitoring subcutaneous bleeding from femoral arteriotomies clinically and that time to hemostasis was significantly reduced by use of the hemostatic dressing.

[Factors affecting the morbidity and mortality of surgical management of vascular gunshot injuries: missed arterial injury and disregarded vein repair]. / Atesli silahla olusan vasküler yaralanmalarin cerrahisinde morbidite ve mortaliteyi etkileyen faktörler: Gözden kaçan arteryel yaralanma, ihmal edilmis ven tamiri.

BACKGROUND: The aim of this study was to establish the clinical course and importance of missed arterial injuries and disregarded venous repair after surgery for gunshot injuries. METHODS: This retrospective study was performed on the operative results of 275 shotgun vascular injury patients' presented to our clinic between January 1992 and December 2004. All patients were analyzed from their medical files and operative notes. The incidence of missed arterial injuries and ignored venous repair, localization and type of vascular complications, limb loss and mortality outcomes were documented. RESULTS: Seventy-five patients (27.27%) for a delayed diagnosis of a missed arterial injury and 91 patients (33.09%) for an ignored venous repair were treated. Complications of missed arterial injuries were determined as followings: false aneurysm n=43 (57.33%), arteriovenous fistula n=20 (26.66%), occlusion n=12 (16%). The missed vascular injury was most commonly observed in superficial femoral artery (n=20). The venous injury was present in 167 patients. Complications of disregarded venous repair were determined as venous edema and deep vein thrombosis. CONCLUSION: Missed arterial injuries and disregarded venous repairs during initial diagnosis or operation affect the morbidity and mortality in gunshot injury patients. After haemodynamic stabilization, gunshot patients should be evaluated by arteriography and venography to determine the anatomic localization of vascular injuries. All vascular continuity should be restored either by primary repair or by an autolog graft. All venous injuries located in popliteal and femoral area should be repaired.

Vascular access complications after cardiac catheterisation: a nurse-led quality assurance program.

BACKGROUND: Vascular access complications may be a cause of discomfort, prolonged hospital stay, and impaired outcomes in patients undergoing cardiac catheterisation. AIMS: To assess vascular access complication in our patients with/without the use of closure devices as a first local benchmark for subsequent quality improvement. METHODS: A nurse-led single-centre prospective survey of all vascular access complications in consecutive patients submitted to cardiac catheterisation during 4 months. RESULTS: The radial and femoral access were used in 78 (14%) and 470 (83%), respectively, of 564 procedures, and a closure device was used in 136 of the latter. A haematoma (any size) was isolated and uneventful in 9.6% of cases. More severe complications (haemoglobin loss >2 g, need for blood transfusion or vascular repair) occurred in 1.2% of cases, namely: in none of the procedures with radial access, and in 0.4% and 2.4% of femoral diagnostic and interventional coronary procedures, respectively. During complicated (n=40) vs uncomplicated (n=172) transfemoral interventions, the activated coagulation time was 309+/-83 vs 271+/-71 s (p=0.004), but the use of closure devices was similar. CONCLUSION: Severe vascular access complications in our patients were fewer than in most reports, and virtually absent in radial procedures. Vigorous anticoagulation was associated with increased complications in our patients, but closure devices were not. A new policy including both the use of the radial access whenever possible, and a less aggressive anticoagulation regimen during transfemoral interventions will be tested.

Comparative morphometric and immunohistological assessment of the development of restenosis after arterial injury and a cholesterol-rich diet in apolipoprotein E -/-mice and C57BL/6 control mice.

OBJECTIVE: Animal models of restenosis have been a cornerstone of testing potential therapies and have improved the understanding of the underlying mechanisms. The aim of this study was to provide an in-depth comparison of the progression of restenotic lesion formation after arterial injury in apolipoprotein E -/- and C57BL/6 control mice. METHODS: In this study, we investigated the difference in lesion formation of apolipoprotein E -/- and C57BL/6 controls on a high-cholesterol, high-fat diet after arterial injury. One week prior to arterial injury of the left femoral artery, mice were started on a high-cholesterol, high-fat diet. Diets were continued after arterial injury until euthanization. At five consecutive time points (2, 5, 10, 15, and 21 days), the intimal hyperplasia in the injured arteries was analyzed. RESULTS: In the C57BL/6 control mice, a continuously increasing lesion formation, consisting primarily of alpha-smooth muscle actin-positive cells, was observed. Lesion formation in apolipoprotein E -/- mice was significantly more pronounced, resulting in complete occlusion of the arteries in four out of five vessels after 21 days. Lesions in apolipoprotein E -/- mice consisted predominantly of lipid-loaded foam cells and alpha-smooth muscle actin-positive cells. Further histological evaluation demonstrated cholesterol crystals in the lesions and neovascularizsation in cases of occlusion. CONCLUSIONS: Thus, apoE -/- mice on a high-cholesterol, high-fat diet provide a more valid model for the characterization of the development of restenotic lesions after mechanical irritation such as angioplasty than C57BL/6 mice.

Functional assessment of human femoral arteries after cryopreservation.

An established method for the cryopreservation of human femoral arteries for subsequent transplantation as allografts has been studied with particular attention to preservation of smooth muscle and endothelium. Human femoral arteries (HFAs) were harvested from multi-organ donors. Two groups were established; a control group of unfrozen HFAs and a group of cryopreserved HFAs. Cryopreservation was performed using RPMI solution containing dimethyl sulfoxide and the rate of cooling was 1 degrees C/min to -40 degrees C and faster thereafter until -150 degrees C was reached. The contraction and relaxation responses of unfrozen and frozen/thawed arteries were assessed by measurement of the isometric force generated by the HFAs in an organ bath. After thawing (warming was at 15 degrees C/min) the maximal contractile response to noradrenaline was 43% of the response of unfrozen HFAs. The endothelium-independent response to sodium nitroprusside was not altered, whereas the endothelium-dependent relaxation response to acetylcholine was slightly altered. The cryopreservation method used provided limited preservation of the contractility of human femoral arteries, and good preservation of both endothelium-independent and endothelium-dependent relaxation responses.

Development of a hematoma classification tool for assessment and documentation post femoral arterial puncture.

Hematoma development following procedures involving femoral arterial puncture is a potentially serious complication, estimated to occur in 0.6% to 17% of the population undergoing these procedures. (Karfonta, 1994). A review of the current literature indicates there is a lack of consistent recording mechanisms and a lack of descriptors to document femoral site observations. Our purpose is to demonstrate the utility of a Hematoma Classification Tool (developed and piloted at the University of Ottawa Heart Institute) for post operative care management of patients following femoral arterial puncture.

In vivo assessment of vascular pathology resulting from laser irradiation. Analysis of 23 patients studied by directional atherectomy immediately after laser angioplasty.

BACKGROUND: The pathological consequences of cardiovascular laser irradiation have been studied extensively in vitro. Previous in vivo studies of laser-induced injury have included analyses of acute and/or chronic findings in experimental animals. Little information, however, is available regarding the acute effects of laser irradiation of human vascular tissues in vivo. METHODS AND RESULTS: To determine the acute pathology resulting from laser irradiation of human vascular tissue in vivo, specimens retrieved from 23 patients by directional atherectomy immediately after laser angioplasty (19 peripheral and four coronary) were examined by light microscopy. Of the 23 patients, three (13.0%) were treated with a metal-capped ("hot-tip") fiber coupled to a continuous-wave neodymium:yttrium-aluminum-garnet (Nd:YAG) laser using up to 18 W power and 18-305 seconds of cumulative exposure time; in all three patients (100%), thermal injury, including frank charring several cell layers thick, was seen along the luminal borders of the atherectomy specimen. In eight of the 23 patients (34.5%), laser angioplasty was performed using a 250-microseconds holmium:YAG laser at fluences up to 2,300 mJ/mm2, a repetition rate of 5 Hz, and 25-200 seconds of cumulative exposure; in seven of eight patients (85.5%), the atherectomy specimen showed signs of vacuolar injury consisting of central and satellite Alcian-blue-negative vacuoles. In two patients (25.0%), there was a "smudged" or "shredded" edge, whereas in one patient, frank signs of thermal injury were observed. Finally, in 12 of the 23 patients (52.2%), laser angioplasty was performed using a 120-nsec excimer laser at fluences up to 60 mJ/mm2, a repetition rate of 25 Hz, and a cumulative exposure time of 21-315 seconds. Pathological findings among these 12 patients were limited to nine patients (75%) in whom a weakly basophilic, smudged, and/or shredded appearance approximately one cell layer thick was observed along the luminal border of the atherectomy specimen and two patients (16.7%) with small foci of vacuolar injury. None of the atherectomy specimens retrieved after excimer laser angioplasty disclosed signs of thermal injury. CONCLUSIONS: These findings document that acute pathological alterations resulting from in vivo laser angioplasty are variable, depending on the laser source used, and are similar to that predicted by experimental studies performed previously in vitro. The prognostic implications of these varying pathological features remain to be clarified.

Emergency arteriography in the assessment of penetrating trauma to the lower limbs.

One hundred emergency arteriographies (EA) were performed in 87 patients with lower limb trauma due to high-velocity missiles. Thirteen patients had bilateral injuries. In 79 cases, EA findings were positive and led to emergency surgery. In 76 cases an arterial injury was found and treated, a positive predictive value of 96% (76/79). In the other 3 cases, no arterial lesion was found (3 false positives). Among the 21 patients with normal findings from angiography, 10 had surgical exploration because of high clinical suspicion of vascular injury. Arterial injury was found in 2 cases (2 false negatives). In 8 patients, arteriography modified the surgical procedure. In the 11 remaining patients, clinical and echo Doppler follow-up results were normal, a negative predictive value of 90% (19/21). Sensitivity was 97%, specificity 86%, and accuracy 95%. These data show that arteriography in stable patients is a safe and accurate procedure. It permits avoidance of unnecessary surgical exploration in selected patients and helps modify the surgical procedure.

Short-term clinical and haemodynamic assessment of balloon aortic valvuloplasty in 30 elderly patients. Discrepancy between immediate and eighth-day haemodynamic values.

Recently, percutaneous aortic valvuloplasty has been considered as a possible palliative procedure in elderly patients with critical valvular stenosis in whom valve replacement is deferred or contra-indicated because of high operative risk. However, the demonstration of the efficacy of such a procedure is based on immediate post dilatation haemodynamic data and clinical improvement. The purpose of this study was to evaluate the haemodynamic consequences of this procedure on the eighth day after a post procedure haemodynamic control. Thirty consecutive patients (mean age 75 +/- 8.4 years) with long-standing aortic stenosis were treated at the time of cardiac catheterization with balloon dilatation. Of these 30 patients, 24 (mean age 76 +/- 8) underwent haemodynamic evaluation eight days after the procedure. Prevalvuloplasty examination revealed a mean aortic valve gradient (MAVG) of 82 +/- 19.9 mmHg, a mean thermodilution calculated cardiac output (CO) of 3.6 +/- 0.9 l min-1 and a mean aortic valve area (VA) of 0.37 +/- 0.14 cm2. Immediate postvalvuloplasty control showed a fall in MAVG to 44.5 +/- 16.7 mmHg (P less than or equal to 0.001), a decrease in CO to 3.3 +/- 1.4 l min-1 (NS) and an increase in VA to 0.60 +/- 0.35 cm2 (P less than or equal to 0.01). Eighth-day haemodynamic control revealed an increase in MAVG to 71 +/- 18.8 mmHg (P less than or equal to 0.001), an increase in CO to 4.1 +/- 1.3 l min-1 (P less than or equal to 0.001) and a decrease in VA down to 0.47 +/- 0.10 cm2 (P less than or equal to 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)