Postmortem diagnosis of Takotsubo syndrome on autoptic findings: is it reliable? A systematic review.

Takotsubo syndrome (TTS) is a cardiac syndrome characterized by transient left ventricular systolic dysfunction in the absence of significant obstructive coronary artery disease. At the autopsy, its diagnosis is often challenging, since it is generally thought that it relates to no characteristic macroscopic or microscopic findings. In order to verify this last statement, we performed a systematic review of the literature following Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement (PRISMA) criteria. To the best of our knowledge, it is the first systematic review addressing this issue. We identified recurring but not pathognomonic (microscopic) features of TTS: contraction band necrosis and non-specific inflammatory changes (e.g., interstitial infiltrates of mononuclear lymphocytes and macrophages) typically in the absence of microscopic findings typical of acute myocardial infarction. In cases of TTS-related sudden death, careful evaluation of anamnesis, autopsy data and post-mortem genetic results (to exclude other causes) should be considered to overcome the complexity of these cases.

Homicide and concealment of the corpse. Autopsy case series and review of the literature.

INTRODUCTION: The concealment of the body following a homicide undermines different moments of the forensic and medico-legal investigations. The aim of the present study is to provide an overview of the literature and the forensic casuistry of the Institute of Legal Medicine of Padova for analyzing and discussing diverse methodological approaches for the forensic pathologist dealing with covered-up homicides. MATERIAL AND METHODS: A literature review, updated until September 2019, was performed, and a literature pool of forensic cases was built. In-house cases were included by conducting a retrospective analysis of the forensic caseworks of Padova of the last 20 years. Data regarding epidemiology, methodology of assessment, methods of concealment, and answers to medico-legal issues were extracted for both data sets. RESULTS AND DISCUSSION: Seventy-eight papers were included in the literature review (78.2% being case reports or case series, 17% retrospective studies, and 6% experimental studies or reviews). Literature and in-house data sets consisted of 145 and 13 cases, respectively. Death scene investigation, radiology, toxicology, and additional analyses were performed in 20-54% of literature and 62-77% of in-house cases. Cover-up by multiple methods prevailed. Death was caused by head trauma in about 40% of cases (both data sets), strangulation in 21% of literature, and 7% of in-house cases, and was undetermined in 17% of literature and 7% of in-house cases. CONCLUSIONS: The methodology of ascertainment should be case-specific and based on a multidisciplinary and multimodal evaluation of all data, including those gained through novel radiological and/or analytical techniques.

Classification and treatment of endothermal heat-induced thrombosis: Recommendations from the American Venous Forum and the Society for Vascular Surgery This Practice Guidelines document has been co-published in Phlebology [DOI: 10.1177/0268355520953759] and Journal of Vascular Surgery: Venous and Lymphatic Disorders [DOI: 10.1016/j.jvsv.2020.06.008]. The publications are identical except for minor stylistic and spelling differences in keeping with each journal's style. The contribution has been published under a Attribution-Non Commercial-No Derivatives 4.0 International (CC BY-NC-ND 4.0), (https://creativecommons.org/licenses/by-nc-nd/4.0/).

The American Venous Forum (AVF) and the Society for Vascular Surgery set forth these guidelines for the management of endothermal heat-induced thrombosis (EHIT). The guidelines serve to compile the body of literature on EHIT and to put forth evidence-based recommendations. The guidelines are divided into the following categories: classification of EHIT, risk factors and prevention, and treatment of EHIT.One major feature is to standardize the reporting under one classification system. The Kabnick and Lawrence classification systems are now combined into the AVF EHIT classification system. The novel classification system affords standardization in reporting but also allows continued combined evaluation with the current body of literature. Recommendations codify the use of duplex ultrasound for the diagnosis of EHIT. Risk factor assessments and methods of prevention including mechanical prophylaxis, chemical prophylaxis, and ablation distance are discussed.Treatment guidelines are tailored to the AVF EHIT class (ie, I, II, III, IV). Reference is made to the use of surveillance, antiplatelet therapy, and anticoagulants as deemed indicated, and the recommendations incorporate the use of the novel direct oral anticoagulants. Last, EHIT management as it relates to the great and small saphenous veins is discussed.

Classification and treatment of endothermal heat-induced thrombosis: Recommendations from the American Venous Forum and the Society for Vascular Surgery.

The American Venous Forum (AVF) and the Society for Vascular Surgery set forth these guidelines for the management of endothermal heat-induced thrombosis (EHIT). The guidelines serve to compile the body of literature on EHIT and to put forth evidence-based recommendations. The guidelines are divided into the following categories: classification of EHIT, risk factors and prevention, and treatment of EHIT. One major feature is to standardize the reporting under one classification system. The Kabnick and Lawrence classification systems are now combined into the AVF EHIT classification system. The novel classification system affords standardization in reporting but also allows continued combined evaluation with the current body of literature. Recommendations codify the use of duplex ultrasound for the diagnosis of EHIT. Risk factor assessments and methods of prevention including mechanical prophylaxis, chemical prophylaxis, and ablation distance are discussed. Treatment guidelines are tailored to the AVF EHIT class (ie, I, II, III, IV). Reference is made to the use of surveillance, antiplatelet therapy, and anticoagulants as deemed indicated, and the recommendations incorporate the use of the novel direct oral anticoagulants. Last, EHIT management as it relates to the great and small saphenous veins is discussed.

The sticky platelet syndrome during carotid endarterectomy.

The sticky platelet syndrome is a congenital disorder, characterized by abnormal platelet aggregation in response to epinephrine and/or adenosine phosphate. We present a case of intraoperative carotid artery thrombosis, after patch angioplasty. The successful repair was only feasible on administration of antiplatelet therapy. Presence of sticky platelet syndrome should be considered during vascular operative interventions, and load of antiplatelet agents should be given in patients with unexplained repeated thrombosis of arterial repair, as we described and reported this case.

Hybrid approach for treatment of behind the knee popliteal artery aneurysms.

We describe herein a combined approach to the treatment of popliteal artery aneurysms (PAA) that averts extensive dissections and potential blood loss particularly in cases of behind-the-knee aneurysms. Over the last 4 years, 13 patients (12 males) with mean age of 75 +/- 8 years were treated for PAAs at our institution with a combined surgical and endovascular approach. The mean size of popliteal aneurysms was 2.9 cm +/- 1.7 cm. One of the 13 cases (8%) was performed for acute ischemia and an additional 5 (38%) for claudication. All operations were performed under general anesthesia in supine position. Vein conduits (eight ipsilateral great saphenous veins, two contralateral great saphenous veins and one arm vein) were utilized for 11 bypasses. Of these, eight were from superficial femoral artery (SFA) to below the knee popliteal artery, two popliteal to popliteal and one SFA to posterior tibial artery. In addition, two expanded polytetrafluoroethylene femoral popliteal bypasses were performed. The distal anastomosis was performed after the popliteal artery was ligated distal to the aneurysm. Next, coil embolization of the aneurysmal sac was performed under fluoroscopic or ultrasound guidance. Coils were embolized through a 5F sheath. Lastly, the popliteal artery was ligated distal to the proximal anastomosis. Completion studies were obtained with duplex in six cases and arteriography in the remaining five cases. Mean follow-up was 11.6 months +/- 9.6. One bypass occluded in 2 months after surgery. One patient demonstrated continued growth of his aneurysm despite coil embolization twice and underwent an open ligation of the branches perfusing the aneurysm from within the sac through a posterior approach. This approach may be particularly useful for PAAs located behind the knee where optimal surgical exposure is often difficult and the collateral circulation is abundant. The proposed technique is simple, effective and averts extensive dissections required to minimize blood loss.

Bilateral internal iliac artery aneurysm infected with Campylobacter fetus.

This is a case report of a patient with Campylobacter fetus involving bilateral internal iliac artery aneurysms. The patient was treated successfully by ligation of the bilateral iliac artery aneurysms and antibiotics. According to a review of the English-language medical literature, this was the first such patient to be reported. A 69-year-old African-American male presented with a past medical history of repair of a 6.6 cm abdominal aortic aneurysm. It had been repaired with a Dacron bifurcated graft in July 2005. The bilateral internal iliac artery aneurysms (right 2.3 cm and left 3.4 cm) were coil embolized intraoperatively. The patient's past medical history was significant for hypertension and coronary artery disease and was status post-stent placement. He re-presented with fever and chills for 8 days in duration at home in March 2007. His fever was 101 to 102 degrees F. He denied vomiting, diarrhea, and a history of recent travel. The patient was admitted to the hospital for a fever workup. After an extensive workup, a left internal iliac artery aneurysm was found to be the source of sepsis. The patient was taken to the operating room for excision of the left internal iliac artery. No purulence was noted, but tissue overlying the aneurysm was thickened and fibrotic. Multiple cultures were taken. The tissue culture came back as C. fetus. Incidentally, the patient's preoperative computed tomographic scan revealed a right internal iliac artery aneurysm that was 4.2 cm on March 28, 2007, and 4.9 cm on April 23, 2007. Postoperatively, the patient's right internal iliac artery aneurysm was noted to be rapidly growing. He was promptly taken to the operating room for ligation of the right internal iliac artery aneurysm. The patient's postoperative course was unremarkable. He was discharged on ciprofloxacin for 14 days.

The safety of radiofrequency ablation of the great saphenous vein in patients with previous venous thrombosis.

BACKGROUND: The safety of radiofrequency ablation (RFA) of the great saphenous vein (GSV) in patients with previous history of deep venous thrombosis (DVT) has not been determined. METHODS: From April 2003 to June 2006, 274 patients (68% women; mean age, 60 years +/- 15 years) underwent 293 consecutive RFA procedures. In the first 15 months, the temperature probe was maintained at 85 degrees C, with a pullback rate of 2 cm/min (85 limbs, 30%); we subsequently changed the protocol to 90 degrees C and a pullback rate of 2 to 3 cm/min (205 limbs, 70%). We identified 29 patients (10%) with a history of DVT or duplex scan evidence of post-thrombotic venous disease; these were compared with the remaining 264 (90%). Postprocedural acute thrombotic (AT) events were analyzed. By the CEAP classification, 204 limbs (70%) were C(2) to C(4), and 89 (30%) were C(5) to C(6). Thirty-seven patients (13%) had a history of superficial thrombophlebitis (SVT). Proximal mean GSV diameter was 0.95 +/- 0.29 cm (range, 0.4-2.3 cm). Concomitant procedures included avulsion phlebectomy in 88 limbs (30%) and perforator vein surgery in 4 (1%). RESULTS: AT events after RFA were detected in 38 limbs (13%), including thrombus protrusion into the sapheno-femoral junction (SFJ) in 24 (8%), common femoral vein in 7 (2.5%), and calf vein DVT in 7 (2.5%). Overall incidence of AT events in limbs with and without evidence of previous DVT was 7% (2 of 29) and 14% (36 of 264), respectively (P = .36). Variables significantly associated with AT events were previous SVT (10 of 37 [27%] vs 28 of 256 [11%], P = .01), a larger GSV diameter (mean 1.1 +/- .39 vs 0.93 +/- 0.27, P < .01), and first protocol (catheter temperature of 85 degrees C with a slower pullback rate in 18 of 88 [20%] vs 20 of 205 [9.7%], P = .02). Concomitant venous operations were associated with an increase in AT events (23% vs 9%; P < .002). By multivariate analysis, larger proximal GSV diameter and previous SVT remained independently statistically significant (P = .049 and P = .0135, respectively). All AT patients were successfully treated with standard anticoagulation. No pulmonary emboli occurred. CONCLUSION: RFA of the GSV in patients with previous venous thromboembolic events is safe and should be offered as an alternative to surgical procedures. These data demonstrate that AT events increase when larger-diameter GSVs are treated.

219 vascular fellows' perception of the future of vascular surgery.

In an attempt to identify the fellows' concerns about the future of the field of vascular surgery, we conducted a survey consisting of 22 questions at an annual national meeting in March from 2004 to 2007. In order to obtain accurate data, all surveys were kept anonymous. The fellows were asked (1) what type of practice they anticipated they would be in, (2) what the new training paradigm for fellows should be, (3) to assess their expectation of the needed manpower with respect to the demand for vascular surgeons, (4) what were major threats to the future of vascular surgery, (5) whether they had heard of and were in favor of the American Board of Vascular Surgery (ABVS), (6) who should be able to obtain vascular privileges, and (7) about their interest in an association for vascular surgical trainees. Of 273 attendees, 219 (80%) completed the survey. Males made up 87% of those surveyed, and 60% were between the ages of 31 and 35 years. Second-year fellows made up 82% of those surveyed. Those expecting to join a private, academic, or mixed practice made up 35%, 28%, and 20% of the respondents, respectively, with 71% anticipating entering a 100% vascular practice. Forty percent felt that 5 years of general surgery with 2 years of vascular surgery should be the training paradigm, while 45% suggested 3 and 3 years, respectively. A majority, 79%, felt that future demand would exceed the available manpower, while 17% suggested that manpower would meet demand. The major challenges to the future of vascular surgery were felt to be competition from cardiology (82%) or radiology (30%) and lack of an independent board (29%). Seventeen percent were not aware of the ABVS, and only 2% were against it; 71% suggested that vascular privileges be restricted to board-certified vascular surgeons. Seventy-six percent were interested in forming an association for vascular trainees to address the issues of the future job market (67%), endovascular training during fellowship (56%), increasing focus on the vascular fellows at national meetings (49%), and representation for the fellows on the national councils (37%). This survey suggests that several significant issues exist in the minds of vascular trainees that have not been addressed and may present opportunities for further dialogue.

Proteomic profiling in early venous stenosis formation in a porcine model of hemodialysis graft.

PURPOSE: To use proteomic analysis to identify up- and downregulated proteins in early venous stenosis formation in a porcine model of hemodialysis graft failure. MATERIALS AND METHODS: Pigs had chronic renal insufficiency created by subtotal renal infarction caused by renal artery embolization. Arteriovenous polytetrafluoroethylene grafts were placed 28 days later and the animals were killed after a further 3 days (n = 4), 7 days (n = 4), or 14 days (n = 4). Proteomic analysis with isotope-coded affinity tags and multidimensional liquid chromatography followed by tandem mass spectrometry was performed on the venous stenosis and control vessels. Expression of proteins was further confirmed by Western blot analysis. The blood urea nitrogen (BUN) and creatinine levels were determined before renal artery embolization and at the time of graft placement. RESULTS: At graft placement, mean BUN and creatinine levels were significantly higher than before embolization (P < .05). Six proteins were identified that were common to all four animals at the same time point. Five proteins (alpha-fetoprotein, fetuin A, macrophage migration inhibitory factor, pyruvate dehydrogenase E1 component, and lactoferrin) were upregulated and one protein (decorin) was downregulated. Expression of macrophage migration inhibitory factor, alpha-fetoprotein, and lactoferrin was further validated with Western blotting. By day 14, lactoferrin and fetuin-A expression were increased significantly in early venous stenosis formation. CONCLUSIONS: Significantly increased expression of lactoferrin and fetuin-A were observed in early venous stenosis by day 14. Understanding the role of lactoferrin and fetuin-A in hemodialysis vascular access failure could help in improving outcomes in patients undergoing hemodialysis.

Adventitial transplantation of blood outgrowth endothelial cells in porcine haemodialysis grafts alleviates hypoxia and decreases neointimal proliferation through a matrix metalloproteinase-9-mediated pathway--a pilot study.

UNLABELLED: Purpose. We hypothesized that adventitial transplantation of blood outgrowth endothelial cells (BOEC) to the vein-to-graft anastomosis of polytetrafluoroethylene grafts will reduce neointimal hyperplasia by reducing hypoxia inducible factor-1alpha (HIF-1alpha), by increasing angiogenesis in a porcine model of chronic renal insufficiency with haemodialysis polytetrafluoroethylene grafts. Because matrix metalloproteinases (MMPs) have been shown to be involved with angiogenesis, the expression of MMPs and their inhibitors was determined. METHODS: Chronic renal insufficiency was created by subtotal renal infarction and 28 days later, arteriovenous PTFE grafts were placed bilaterally from the carotid artery to the jugular vein. Autologous blood outgrowth endothelial cells labeled with Lac Z were transplanted to the adventitia of the vein-to-graft anastomosis using polyglycolic acid scaffolding and scaffolding only to other side (control). Animals were killed 14 days later and vessels were explanted from the vein-to-graft anastomosis of both sides and underwent immunohistochemical analysis, western blotting and zymography for HIF-1alpha, MMP-2, MMP-9, TIMP-1 and TIMP-2. BOEC were also made hypoxic and normoxic for 12, 24 and 48 h to determine protein expression for MMPs and TIMPs. RESULTS: Under hypoxia, BOEC significantly increased the expression of pro MMP-2 by 12 h and TIMP-2 by 24 h when compared to normoxic cells (P < 0.05). Transplantation of BOEC resulted in a significant decrease in both HIF-1alpha and intima-to-media ratio with a significant increase in both pro and active MMP-9 when compared to control vessels (P < 0.05). MMP-9 activity was localized to the neointima of the transplanted vessels by immunohistochemistry. There was increased CD31 density with engraftment of BOEC cells into the neointima of both the transplanted vessels compared to controls (P = NS). CONCLUSION: Transplantation of BOEC resulted in a significant decrease in intimal hyperplasia and HIF-1alpha with a significant increase in both pro and active MMP-9 that was localized to the neointima of transplanted vessels. The increase in MMP-9 offers a possible mechanism for angiogenesis and the reduced intima-to-media ratio. Furthermore, we observed that BOEC had homed to the neointima of the contralateral vessels that had increased levels of HIF-1alpha, suggesting that hypoxia may be an important stimulus for BOEC migration.

Limitations of and lessons learned from clinical experience of 1,020 duplex arteriography.

OBJECTIVE: Due to the inherent risks, deficiencies and cost associated with contrast arteriography (CA), our group has been utitilizing duplex arteriography (DA) for evaluating the arteries of the lower extremity for patients undergoing lower extremity revascularization. In an effort to further explore the strengths and weaknesses of DA, we reviewed our evolving experience with DA from January 1, 1998, to January 1, 2005. PATIENTS AND METHODS: The arterial segments starting from mid-abdominal aorta to the pedal arteries were studied in cross-sectional and longitudinal planes using a variety of scanheads of 7-4, 10-5, 12-5, 5-2 and 3-2 MHz extended operative frequency range to obtain high-quality B-mode, color and power Doppler images as well as velocity spectra. In 906 patients, 1,020 duplex arteriograms were obtained. The ages ranged from 30-98 years old with a mean of 73+/-11 (SD) years. Fifty percent of the patients were diabetics. Indications for the examination included: tissue loss (409), rest pain (221), claudication (310), acute ischemia (74), popliteal aneurysm (45), SFA aneurysm (2), abdominal aortic aneurysms (AAA) (10) and failing bypass (55). Prior procedures had been performed in 262. DA was performed by six technologists (4 of whom are MDs). In all, 207 DA were performed intraoperatively and the remainder, preoperatively. RESULTS: The resultant procedures based upon DA included: bypass to the popliteal artery (262) and bypass to an infrapopliteal artery (325), endovascular procedures (363), thrombectomy (11), embolectomy (9), inflow bypass procedures to the femoral arteries (46), débridment (4), amputation (8) and no intervention (75). The areas not visualized well included: iliac (73), femoral (26), popliteal (17), and infrapopliteal (221). Additional imaging after DA was deemed necessary in 102 cases to obtain enough information to plan lower extremity revascularization. Factors associated with increased need to obtain CA included: DM (p<.001), infrapopliteal calcification (p<.001), older age (p = .01) and limb threatening ischemia (p<.001). Factors not associated with the need to obtain CA included: which technologist performed the exam, whether the technologist has a medical degree and whether the patient underwent prior revascularization. CONCLUSIONS: In 90% of patients reviewed, DA is able to obtain the needed information to plan lower extremity revascularization. Severe tibial vessel calcification is the most common cause of an incomplete DA exam and determines when alternative imaging modalities need to be obtained.

Effect of Duplex Arteriography in the Management of Acute Limb-Threatening Ischemia From Thrombosed Popliteal Aneurysms.

The role of routine use of duplex arteriography to diagnose thrombosis of popliteal artery aneurysm as a cause of acute lower extremity ischemia is investigated. In all, 109 patients (group 1) from 1994 to 1997 and 201 patients from 1998 to 2001(group 2) presenting with acute limb-threatening ischemia were studied. None of the group 1 patients underwent preoperative duplex arteriography, and no diagnosis of acute popliteal artery aneurysm thrombosis was made. Ten patients with acute ischemia due to thrombosed popliteal artery aneurysm were identified in group 2 when preoperative duplex arteriography was routinely performed. Urgent revascularization was performed based on the results of duplex arteriography. Six patients had functioning bypasses with a mean follow-up of 15.6 months. There were 3 deaths, 2 within 30 days and 1 after 2(1/2) years with functioning grafts. One patient was lost to follow-up. Routine use of duplex arteriography may provide the diagnosis and may identify the available outflow vessels for popliteal artery aneurysm.

Use of StarClose for brachial artery closure after percutaneous endovascular interventions.

The objective of this study was to evaluate a percutaneous extravascular closure device (StarClose, Abbott Vascular, Redwood City, CA) after brachial endovascular approach. From 2004 to 2006, 29 patients received StarClose for brachial closure. Primary endpoints were successful deployment and absence of procedure-related morbidity, secondary endpoints were brachial artery patency on duplex and absence of late (> 30 days) complications. The device was successfully deployed in all patients. In two patients (6.8%) local complications occurred: one patient developed a large hematoma successfully treated with prolonged compression and a second patient presented with brachial artery occlusion requiring operative intervention. After a mean follow-up of 7.5+/-7.2 months, all patients had a palpable brachial/radial pulse; none had signs of infection, distal embolization or neurological deficits. On ultrasound b-mode imaging, the clip was visible as a 4 mm echolucent area at the outer anterior wall of the artery. Based on the peak systolic velocity ratios between the site of StarClose and proximal brachial artery (mean 1.08+/-0.2), none of the studied patients had a significant stenosis at the site of closure. StarClose is safe and effective in providing hemostasis following interventional procedures through the brachial artery; further advantages include patients comfort and early discharge.

Increased expression of hypoxia-inducible factor-1 alpha in venous stenosis of arteriovenous polytetrafluoroethylene grafts in a chronic renal insufficiency porcine model.

PURPOSE: To create a more clinically relevant model of hemodialysis graft failure in pigs by creating chronic renal insufficiency before polytetrafluoroethylene (PTFE) hemodialysis graft placement and to determine the expression of hypoxia-inducible factor-1 alpha (HIF-1 alpha) at the vein-to-graft anastomosis (VGA). MATERIALS AND METHODS: Chronic renal insufficiency was created in 14 castrated juvenile male pigs with complete embolization of the left renal artery and the partial embolization of the right renal artery by infusing 150-250-mum polyvinyl acrylide spherical particles. The efficacy of the embolization was assessed by determining the amount of polyvinyl acrylide particles used per kidney, the weight of the kidneys at sacrifice, and kidney function (blood urea nitrogen [BUN] and creatinine levels). Twenty-eight days after embolization, PTFE grafts were placed from the carotid artery to the ipsilateral jugular vein and removed 3, 7, and 14 days after graft placement. Western blot for HIF-1 alpha was performed in the VGA and control vessel. RESULTS: The left kidney required two times the polyvinyl acrylide particles than did the right kidney (P < .05). The right kidney weighed nearly three times more than the left (P < .05). The BUN and creatinine levels at graft placement were significantly higher than those at baseline (P < .05). Four grafts were patent at day 3, four at day 7, and four at day 14. By day 7, the mean HIF-1 alpha at the VGA had increased significantly when compared with that of control vessels (P < .05). CONCLUSIONS: A more clinically relevant porcine model of hemodialysis graft failure was created, and there was significantly increased expression of HIF-1 alpha by day 7 at the VGA.

Increased shear stress with upregulation of VEGF-A and its receptors and MMP-2, MMP-9, and TIMP-1 in venous stenosis of hemodialysis grafts.

Venous injury and subsequent venous stenosis formation are responsible for hemodialysis graft failure. Our hypothesis is that these pathological changes are in part related to changes in wall shear stress (WSS) that results in the activation of matrix regulatory proteins causing subsequent venous stenosis formation. In the present study, we examined the serial changes in WSS, blood flow, and luminal vessel area that occur subsequent to the placement of a hemodialysis graft in a porcine model of chronic renal insufficiency. We then determined the corresponding histological, morphometric, and kinetic changes of several matrix regulatory proteins including VEGF-A, its receptors, matrix metalloproteinase (MMP)-2, MMP-9, tissue inhibitor of matrix metalloproteinase (TIMP)-1, and TIMP-2. WSS was estimated by obtaining blood flow and luminal vessel area by performing phase-contrast MRI with magnetic resonance angiography in 21 animals at 1 day after graft placement and prior to death on day 3 (n = 7), day 7 (n = 7), and day 14 (n = 7). At all time points, the mean WSS at the vein-to-graft anastomosis was significantly higher than that at the control vein (P < 0.05). WSS had a bimodal distribution with peaks on days 1 and 7 followed by a significant reduction in WSS by day 14 (P < 0.05 compared with day 7) and a decrease in luminal vessel area compared with control vessels. By day 3, there was a significant increase in VEGF-A and pro-MMP-9 followed by, on day 7, increased pro-MMP-2, active MMP-2, and VEGF receptor (VEGFR)-2 (P < 0.05) and, by day 14, increased VEGFR-1 and TIMP-1 (P < 0.05) at the vein-to-graft anastomosis compared with control vessels. Over time, the neointima thickened and was composed primarily of alpha-smooth muscle actin-positive cells with increased cellular proliferation. Our data suggest that hemodialysis graft placement leads to early increases in WSS, VEGF-A, and pro-MMP-9 followed by subsequent increases in pro-MMP-2, active MMP-2, VEGFR-1, VEGFR-2, and TIMP-1, which may contribute to the development of venous stenosis.

Gray-scale median of the atherosclerotic plaque can predict success of lumen re-entry during subintimal femoral-popliteal angioplasty.

OBJECTIVE: This study assessed whether the duplex ultrasound (DUS)-derived gray-scale median (GSM) of the most six distal portion of the occluded femoral-popliteal arterial segment can predict success of lumen re-entry for subintimal angioplasty. METHODS: During the last 3 years, 108 patients (62% men) with a mean age of 73 +/- 10 years underwent 116 primary attempted DUS-guided subintimal angioplasties of the femoral-popliteal segment. Preprocedural B-mode DUS images of the plaque at the most distal occlusion segment were digitalized and normalized using Photoshop (Adobe, San Jose, Calif) software and standard criteria (gray level, 0 to 5 for lumen blood and 185 to 190 for the adventitia on a linear scale of 0 to 255). Overall GSM of the plaque segment about 2 cm long, immediately before the planned re-entry point to the true arterial lumen, was used for retrospective correlation with procedure success and other clinical indicators. RESULTS: Mean plaque GSM for all cases was 22.5 +/- 12.6 (range, 3 to 60). The overall success rate of subintimal angioplasty procedures was 85%. Mean plaque GSM for 99 successful cases (18.4 +/- 7.8) was significantly lower than for 17 cases (46.4 +/- 8.1) where we failed (P < .0001). We failed in 90% of 19 cases with GSM >35, in 71% of 24 cases with GSM >20, and in 50% of 34 cases with GSM >25. There was no statistically significant difference (P = .45) between plaque GSM in 64 patients with diabetes (23.3 +/- 13.5) compared with 52 nondiabetic patients (21.5 +/- 11.4). Similarly, plaque GSM was not statistically different (P = .9) in 52 patients with renal insufficiency (22.7 +/- 13.2) compared with 64 patients with normal creatinine levels (22.4 +/- 12.2). At the 6-month follow-up, no statistically significant difference was found between mean GSM (17.8 +/- 7.8) in 47 stenosis-free cases compared with mean GSM (18 +/- 6.8) in 22 cases where severe restenosis (>70%) or reocclusion was identified by DUS scan (P = .4). CONCLUSIONS: Plaque echogenicity represented by DUS-derived GSM can be used to predict the success of primary subintimal femoral-popliteal angioplasties.

Predictive factors of femoropopliteal patency after suboptimal duplex-guided balloon angioplasty and stenting: is recoil a bad sign?

Currently, the value of stenting during femoropopliteal balloon angioplasty (FPBA) remains unclear. Herein we evaluate the patency rates of successful duplex-guided balloon angioplasty (DAGBA) alone versus suboptimal DAGBA followed by stenting and the prestenting dissection versus recoil as potential indicators of stent success or failure. Over a period of 27 months, we performed 291 duplex-guided FPBAs (194 stenoses; 97 occlusions) on 244 limbs in 220 patients. Disabling claudication was the indication in 67%. Critical limb ischemia was the indication in the remaining 33%. Self-expanding nitinol stents were used when plaque dissection and/ or recoil caused diameter reduction > or = 40%. Serial follow-up duplex scans were obtained. Severe restenosis (> 70%) was measured by B-mode imaging and a peak systolic velocity ratio > 3. Follow-up ranged from 1 to 41 months (mean 10 +/- 8.3 months). The overall mean interval for restenosis and occlusion was 6.5 +/- 4.2 months and 5.6 +/- 6.1 months, respectively. Stents did affect overall patency results compared with not using stents. Reasons for stenting were plaque recoil, dissection, or both in 98 (53%), 44 (24%), and 42 (23%) cases, respectively. Six-month patency was 59%, 94%, and 69%, respectively. The difference between plaque recoil and dissection was significant (p<.04). The use of stents during FPBA may be associated with balloon angioplasty site failure in the femoropopliteal segment. To our knowledge, this is the first report ever to document plaque recoil as a predictor of balloon angioplasty site failure notwithstanding stent placement.