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F J Veith

Publications and source records attributed to F J Veith.

At least 19 recordsLinked to original sources
PubMed2004

The value of subintimal angioplasty in the management of critical lower extremity ischemia: failure is not always associated with a rethreatened limb.

The technique of subintimal angioplasty was developed in Leicester, UK in 1987. Recently a growing number of centers in Europe and the United States have been gaining experience with this technique. Promising results have been reported and the application of the technique expanded to include the iliac and crural arteries. Despite this growing experience, the technique has not gained widespread acceptance. It has been speculated that this may be due in large part to a steep learning curve and/or skepticism regarding the procedure given the relatively low primary patency rates seen in most series. However, limb salvage rates from these same and other series have been considerably higher than the patency rates, and advocates of the technique have urged that the results of clinical series be viewed with these limb salvage rates primarily in mind. Although primary patency rates remain low for patients undergoing subintimal angioplasty limb salvage rates remain high. Given the many advantages of this technique, including reduced anesthesia requirements, a minimally invasive approach, and potential reductions in length of stay and cost subintimal angioplasty will continue to have a role in the treatment of lower extremity ischemia. When applied judiciously, bypass options are preserved. This does not mean that the availability of this technique should be used as justification to lower the threshold for the treatment of mild intermittent claudication. When a subintimal angioplasty fails, it frequently does so without the recurrence of symptoms, especially when a gangrenous lesion or ulcer has healed. Various approaches for the performance of subintimal angioplasty and clinical results will be discussed.

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PubMed2004

Relationship of proximal fixation to renal dysfunction in patients undergoing endovascular aneurysm repair.

Technological advancements have lead to dramatic improvements in stentgraft device design resulting in more trackable delivery systems and transrenal uncovered stents and barbs for better fixation. Transrenal bare-stents may limit stentgraft migration, particularly in patients with short or flared proximal aortic necks. However, potential disadvantages might be in worsening renal function, particularly in patients with preexisting renal insufficiency. We retrospectively analyzed our recent 7 year experience of patients undergoing endovascular aneurysm repair (EVAR) using a variety of stentgrafts with and without transrenal bare-stent fixation. Patients were divided into 2 groups; infrarenal fixation (IRF) vs transrenal fixation (TRF), or patients with preoperative serum Cr values that were normal (= or <1.5 mg/dl) vs slightly elevated (1.6-2 mg/dl), vs markedly elevated (2.1- 3.5 mg/dl). The exclusion criteria included patients with chronic renal insufficiency (CRI) on hemodialysis, and preoperative high-grade renal artery stenoses requiring angioplasty and stenting. Of 705 patients that underwent EVAR, 496 (IRF: 385 [78%], and TRF: 111 [22%]) were available with routine evaluations of serum Cr and CT scans. Preexisting comorbidities, mean procedure contrast volume, and postprocedure follow-up were similar in both groups. In the immediate postoperative period, mean serum Cr did not change significantly in either the IRF group (1.3+/-0.7 mg/dl to 1.2+/-0.9 mg/dl) or the TRF group (1.3+/-0.5 mg/dl to 1.3+/-0.6 mg/dl). Mean serum Cr did, however, significantly increase over longer follow-up in both groups: 1.4+/-0.8 mg/dl for IRF (P<0.03), and 1.5 +/- 0.8 mg/dl for TRF (P<0.01). Cr clearance was similarly unchanged in the immediate postoperative period (58+/-23 to 61+/-25 ml/min/1.73 m2 for IRF group, 53+/-17 to 55+/-17 ml/min/1.73 m2 for TRF group), but was significantly decreased in longer follow-up (53+/-23 ml/min/1.73 m2 for IRF, p<0.02: and 48+/-16 ml/min/1.73 m2 for TRF, P<0.01). There were no significant differences in serum Cr increase (p=0.19) or Cr clearance decrease (p=0.68) between the IRF and TRF groups. Small renal infarcts were noted in 6 patients (1.6%) in the IRF group, and in 8 patients (7%) in the TRF group (p=0.37). Of patients with normal preoperative renal function, renal dysfunction developed in 7.7% of IRF group and 6.1% of TRF group (p=0.76). In patients with preexisting CRI, renal dysfunction developed in 18.2% of IRF group, and 17.1% of TRF group (p=0.95). Eight patients with postoperative renal dysfunction, 5 (1.3%) from IRF group and 3 (2.7%) from TRF group subsequently required hemodialysis, and this difference was not statistically significant (p=0.91). We also analyzed 200 consecutive patients undergoing EVAR with intra-arterial contrast agents with and without preexisting CRI not on dialysis. The groups were identified on the basis of preprocedure serum Cr: group 1 (n=108), Cr less than 1.5 mg/dL (normal range); group 2 (n=65), Cr 1.5 to 2.0 mg/dL; group 3 (n=27), Cr 2.1 to 3.5 mg/dL. Routine precautions in patients with CRI included preoperative intravenous hydration with 2 L of normal saline solution, discontinuation of all nephrotoxic drugs, intraoperative administration of mannitol (0.5 g/kg intravenously), and use of nonionic, low osmolar intra-arterial contrast agent (Omnipaque 350). One-hundred and eight patients had normal renal function (group 1), and 92 patients had preexisting CRI with baseline Cr 1.5 to 2.0 mg/dL (group 2, n=65) or 2.1 to 3.5 mg/dL (group 3, n=27). Comorbid conditions included coronary artery disease (group 1, 51%; group 2, 49%; group 3, 59%), hypertension (group 1, 39%; group 2, 46%; group 3, 52%), and diabetes mellitus (group 1, 25%; group 2, 35%; group 3, 48%). In groups 1, 2, and 3, the mean volume of low osmolar contrast agent used was 210 cc, 160 cc, 130 cc, respectively; hemodynamic instability developed in 3, 1, and 1 patient, respectively. The incidence of postoperative complications between the 3 study groups was not statistically different. In grications between the 3 study groups was not statistically different. In group 1 a transient increase in serum Cr (>30% over baseline and >1.4 mg/dL) was noted in 3 patients (2.7%), 2 of whom (1.9%) required temporary hemodialysis and 1 (0.9%) who died of renal failure. In group 2 a transient increase in serum Cr was noted in 2 patients (3.1%); both patients (3.1%) required temporary hemodialysis, and 1 patient (1.5%) died of renal failure. In group 3 a transient increase in serum Cr was noted in 2 patients (7.4%); 1 patient (3.7%) required temporary hemodialysis, and 1 patient (3.7%) died of renal failure. Perioperative hypotension significantly increased the risk for elevated serum Cr and death (p<0.05), and larger contrast volume was associated with an increase in serum Cr (p<0.05) during the postoperative period. Following EVAR renal function declines slightly with both IRF and TRF. Our data show no overall difference between patients with IRF and TRF with respect to infarcts, decline in renal function, or onset of dialysis. There were a slightly greater number of renal infarcts in the TRF group, but these infarcts were clinically inconsequential. In patients with CRI, EVAR with intra-arterial radiographic contrast agents is believed to impair renal function, and CRI is considered a relative contraindication to the procedure. Results of our investigation indicate that risk for worsening renal insufficiency, dialysis, and death is only slightly and not significantly greater in patients with CRI compared with patients with normal renal function. With appropriate precautions of avoiding perioperative hypotension and limiting the volume of nonionic contrast agents, CRI need not be a contraindication for EVAR with intra-arterial contrast agents.

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PubMed2003

Conservative observational management with selective delayed repair for large abdominal aortic aneurysms in high risk patients.

AIM: Abdominal aortic aneurysms (AAAs) larger than 5.5 cm should generally undergo elective repair. However, some of these patients have serious comorbid conditions, which greatly increase operative risk. This study evaluated the outcomes of nonoperative, observational management and selective delayed AAA repair in high-risk patients with large infrarenal and pararenal AAAs. METHODS: Among 226 patients with AAAs >5.5 cm, we selected 72 with AAAs 5.6-12.0 cm (mean 7.0 cm) for periods of nonoperative management because of their prohibitive surgical risks. Comorbid factors included a low ejection fraction of 15-34% (mean 22%) in 18 patients; FEV1 <50% (mean 38%) in 25; prior laparotomy in 10; and morbid obesity in 22. Follow-up was complete in the 72 patients for the 6-76 months (mean 23 months) that they were treated nonoperatively. Fifty-three patients ultimately underwent repair because of AAA enlargement or onset of symptoms after 6-72 months (mean 19 months) of observational treatment. RESULTS: Of the 72 selected patients, 54 (75%) are living and 18 (25%) are dead. Seven patients undergoing only nonoperative treatment presently survive after 28-76 months (mean 48 months). Of the 18 deaths, AAA rupture occurred in only 3 patients (4%) who had been observed for 12, 31, and 72 months before rupture. Nine other deaths (13%) occurred after 6-72 months from comorbidities unrelated to the patient's AAA. Six of the 53 patients undergoing delayed AAA repair died within 30 days of operation (11% mortality). The mortality for the 154 good risk AAA patients, who underwent prompt open or endovascular repair, was 2.2%. CONCLUSION: These data indicate that some patients with large AAAs and serious comorbidities are acceptably managed for long periods (6-76 months) by nonoperative means. Substantial delays of 12 to 76 months resulted in an AAA rupture rate of only 4%, while 13% of these patients (9 of 72) died of their comorbidities unrelated to AAA rupture or surgery and mortality in this group of patients, when operated on, was 11% (6 of 53). These findings support the selective use of nonoperative observational management in some patients with large AAAs and serious comorbidities.

Aortic Aneurysm, Abdominal↗
PubMed2002

Endovascular approaches to ruptured infrarenal aorto-iliac aneurysms.

BACKGROUND: Ruptured abdominal aortoiliac aneurysms (RAAAs) carry a high mortality when treated by open surgical repair. Since 1994, we have employed endovascular approaches to treat this entity. METHODS: Patients with presumed RAAAs were treated with restricted fluid resuscitation (hypotensive hemostasis), rapid transport to the operating room, placement of a transbrachial or transfemoral guidewire under local anesthesia, and urgent arteriography. In patients with suitable anatomy, endovascular graft repair was performed. If the anatomy was unsuitable, standard open repair was performed. If the patient had circulatory collapse, proximal balloon control was employed. RESULTS: Of 31 patients managed in this fashion, 25 underwent endovascular graft repair. Six required open repair. Total operative mortality was 9.7% (3 patients). Only 10 patients required proximal balloon aortic control. CONCLUSIONS: Endovascular techniques (proximal balloon control and endografts) may improve treatment outcomes for RAAAs. Restricted resuscitation (hypotensive hemostasis) can be effective in the RAAA setting.

Aneurysm, Ruptured↗
PubMed2001

All sealed endoleaks are not the same: a treatment strategy based on an ex-vivo analysis.

PURPOSE: factors contributing to pressure transmission through thrombosed or sealed endoleaks have not been elucidated. The purpose of this investigation was to create an ex-vivo model that mimics patent and sealed endoleaks and that can quantitatively analyse the effects of length, diameter and thrombus on pressure transmission to the interior of the aneurysm sac. METHODS: In the ex-vivo model, endoleak channels (ELCs) of various lengths (2 cm, 6 cm, 10 cm) and diameters (0.6 cm, 1.0 cm, 1.4 cm) were constructed using polytetrafluoroethylene (PTFE) grafts and attached to an artificial aneurysm sac. These ELCs were incorporated within a mock circulation made of rubber tubing connected to a pulsatile pump. Peak systolic pressure (PSP) was recorded in the aneurysm sac, distal to each ELC. Subsequently the ELCs were filled with human thrombus, and the pressure measurements repeated (n =5). Data was evaluated by regression analysis. RESULTS: Peak systolic pressure in the artificial circulation was maintained at 150 mmHg. In the absence of thrombus pressure did not change across the ELC, regardless of its length or diameter. In the presence of organised thrombus, the pressure curves distal to the ELC were dampened, and the pressure reduction was directly proportional to the length and inversely proportional to the diameter of the ELC. Regression analysis indicated statistical significance. CONCLUSION: In the absence of thrombosis, pressure transmitted via an ELC to the aneurysm sac is unchanged regardless of its length or diameter. All sealed endoleaks also transmit pressure. However, when an endoleak has thrombosed, pressure reduction is directly proportional to the length and inversely proportional to the diameter of its channel. This ex-vivo model suggests that Type 2 endoleaks with longer channels and smaller diameters would derive a greater benefit from adjunctive manoeuvres (coil embolisation) that hasten thrombosis. On the other hand, thrombosis of endoleaks with short and wide channels (e.g. Type 1) may not result in substantial pressure reduction within the aneurysm sac and a successful outcome.

Aortic Aneurysm↗
PubMed2001

Fluoroscopically assisted thromboembolectomy: should it be routine?

The treatment of acute limb ischemia secondary to thromboembolic disease has become significantly more difficult because of the increased proportion of elderly patients presenting with complex patterns of atherosclerotic disease. The presence of multiple medical comorbidities also complicates operative and perioperative management in these patients. Neither the techniques nor catheter designs have changed significantly since the introduction of the balloon embolectomy catheter in 1963, which permitted extraction of clot from remote sites. The authors believe that the use of intraoperative fluoroscopy and the performance of fluoroscopically assisted thromboembolectomy (FATE) greatly improves the results of this treatment in many cases. FATE facilitates catheter passage through tortuous, diseased arteries, identifies residual thrombus and underlying lesions, reduces vessel damage caused by balloon overinflation, and decreases the risk of catheter-induced dissection or atherosclerotic plaque displacement. Intraoperative fluoroscopy helps determine the need for as well as guides adjunctive procedures such as angioplasty and stenting. Such procedures can be performed at the time of the thromboembolectomy simplifying and expediting treatment.

Fluoroscopy↗
PubMed2001

Current status of carotid bifurcation angioplasty and stenting based on a consensus of opinion leaders.

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

Angioplasty↗
PubMed2001

Unilateral and bilateral hypogastric artery interruption during aortoiliac aneurysm repair in 154 patients: a relatively innocuous procedure.

OBJECTIVE: Hypogastric artery (HA) occlusion during aortic aneurysm repair has been associated with considerable morbidity. We analyzed the consequences of interrupting one or both HAs in the standard surgical or endovascular treatment of aortoiliac aneurysms (AIAs). METHODS: From 1992 to 2000, 154 patients with abdominal aortic aneurysms (n = 66), iliac aneurysms (n = 28), or AIAs (n = 60) required interruption of one (n = 134) or both (n = 20) HAs as part of their endovascular (n = 107) or open repair (n = 47). Endovascular treatment was performed with a variety of industry- or surgeon-made grafts in combination with coil embolization of the HAs. The standard surgical techniques included oversewing or excluding the origins of the HAs and extending the prosthetic graft to the external iliac or femoral artery. RESULTS: There were no cases of buttock necrosis, ischemic colitis requiring laparotomy, or death when one or both HAs were interrupted. Persistent buttock claudication occurred after 16 (12%) of the unilateral and 2 (11%) of the bilateral HA interruptions. Impotence occurred in 7 (9%) of the unilateral and 2 (13%) of the bilateral HA interruptions. Minor neurologic deficits of the lower extremity were observed in 2 (1.5%) of the patients with unilateral HA interruption. CONCLUSIONS: Although HA flow should be preserved if possible, selective interruption of one or both HAs can usually be accomplished safely during endovascular and open repair of anatomically challenging AIAs. We believe other comorbid factors such as shock, distal embolization, or the failure to preserve collateral branches from the external iliac and femoral arteries may have contributed to the morbidity in other reports of HA interruption.

Aged↗
PubMed2001

Efficacy of a proximal occlusion catheter with reversal of flow in the prevention of embolic events during carotid artery stenting: an experimental analysis.

OBJECTIVE: The role of percutaneous angioplasty and stenting of carotid bifurcation lesions has been limited by its potential for producing embolic debris. We evaluated the efficacy of a proximal occlusion catheter (POC) in the prevention of embolic events during carotid artery stenting. In addition, pressure measurements relevant to the clinical application of this device were obtained from 10 patients undergoing carotid endarterectomy. METHODS: The POC is a guiding catheter with an occlusion balloon attached on the outside of the catheter at its distal end. Occlusion of the common carotid artery (CCA) was achieved by inflating the balloon while access to carotid bifurcation lesions was obtained through the inner lumen. The POC was inserted in the CCA of 10 dogs via the femoral artery. The side port of the POC was connected to a sheath placed in the femoral vein, thereby creating an external arteriovenous shunt. Ten artificial radiopaque particles simulating embolic particles and contrast agent were introduced in the CCA and monitored fluoroscopically. As a control, the same procedure was performed with a standard guiding catheter without an occlusion balloon. In 10 patients undergoing carotid endarterectomy, the internal carotid artery (ICA) and external carotid artery stump pressures and the pressure in the internal jugular vein were measured. RESULTS: Without the external arteriovenous shunt, in all animals there was prograde flow in the distal CCA despite CCA occlusion. This flow was derived from the thyroid artery. However, once the arteriovenous shunt was activated, reversal of flow in the distal CCA was achieved in each animal, and all the artificial particles were recovered from the side port of the POC. In the control group, each particle embolized to the brain (100%, P <.01). In the patients, the mean stump pressures in the ICA and external carotid artery and the jugular vein pressure were 51.8 +/- 14.2, 62.2 +/- 15.1, and 6.5 +/- 3.5 mm Hg, respectively. In each case, the jugular vein pressure was the lowest among the three. CONCLUSIONS: Obtaining proximal CCA control by inflating the POC does not sufficiently prevent embolization. However, reversal of flow in the ICA can always be created with the external shunt, which effectively prevents embolization. Thus, POC may markedly lower procedural stroke rates during carotid artery stenting. The ability of POC to prevent embolization before crossing the lesion with a guidewire may be an important advantage over other distal protection devices.

Angioplasty, Balloon↗
PubMed2001

Diameter changes in isolated iliac artery aneurysms 1 to 6 years after endovascular graft repair.

OBJECTIVE: Precise diameter changes in iliac artery aneurysms (IAAs) after endovascular graft (EVG) repair are yet to be determined. This report describes the midterm size changes in isolated IAAs 13 to 72 months after treatment with an EVG. METHODS: From January 1993 to April 1999, 31 patients with 35 true isolated IAAs (32 common iliac and 3 hypogastric) had these lesions treated with EVGs and coil embolization of the hypogastric artery or its branches. The EVG used in this study consisted of a balloon-expandable stent attached to a polytetrafluoroethylene graft. Contrast-enhanced spiral computed tomographic scans were performed at 3- to 6-month intervals to follow the aneurysms for change in diameter and endoleaks. RESULTS: Thirty patients had a decrease in the size of their iliac aneurysms with EVG repair. All EVGs remained patent. All patients, except for one, were followed up for 13 to 72 months (mean, 31 months). The pretreatment aneurysm size ranged from 2.5 to 11.0 cm in diameter (mean, 4.6 +/- 1.62 cm). After EVG treatment, the aneurysms ranged from 2.0 to 8.0 cm in diameter (mean, 3.8 +/- 1.36 cm). The change in aneurysm diameter ranged from 0.5 to 3.1 cm (mean, 1.1 +/- 0.62 cm) with an average change of -0.516 +/- 0.01 cm/y for the first year. Five patients died of their intercurrent medical conditions during the follow-up period. One of the patients had a new endoleak and an increase in common iliac aneurysm size 18 months after EVG treatment, despite an early contrast-enhanced computed tomographic scan that showed no endoleak. This patient's aneurysm ruptured, and a standard open surgical repair was successfully performed. Another patient had a decrease in hypogastric aneurysm size after EVG treatment and no radiographic evidence of an endoleak, but eventually the aneurysm ruptured. He was successfully treated with a standard open surgical repair. CONCLUSIONS: EVGs can be an effective treatment for isolated IAAs. Properly treated with EVGs, IAAs decrease in size. The enlargement of an IAA, even if no endoleak can be detected, appears to be an ominous sign suggestive of an impending rupture. IAAs that enlarge should be closely evaluated for an endoleak. If an endoleak is detected, it should be eliminated if possible. If an endoleak cannot be found, open surgical repair should be considered.

Aged↗
PubMed2001

Hypogastric artery aneurysm rupture after endovascular graft exclusion with shrinkage of the aneurysm: significance of endotension from a "virtual," or thrombosed type II endoleak.

Type II endoleaks, resulting from retrograde branch flow, after endovascular graft aneurysm exclusion are considered benign because they usually thrombose and are commonly associated with stable or shrinking aneurysm sacs. We report a hypogastric artery aneurysm rupture from endotension from an undetected, thrombosed Type II endoleak, associated with sac shrinkage. The patient had undergone an endovascular graft repair of a 4-cm right common iliac artery and 9-cm hypogastric artery aneurysm with distal hypogastric artery coil embolization. Serial computed tomography scans revealed no endoleak and a hypogastric aneurysm thrombosis with shrinkage. Eighteen months later, the aneurysm ruptured as a result of pressurization from backbleeding, patent branches.

Aged↗
PubMed2001

Endoscopically assisted in situ lower extremity bypass graft: a preliminary report of a new minimally invasive technique.

OBJECTIVE: Lower extremity arterial reconstructions with in situ greater saphenous vein (GSV) are an important component of limb salvage surgery. Initially, the procedure was performed through continuous skin incisions for side branch occlusion and valve lysis with a wound complication rate of 5% to 25%. To decrease these complications, we used endoscopic GSV harvest equipment in 25 in situ vein bypass grafts in 25 patients performed over 24 months. METHODS: The procedures were performed with three skin incisions: two for arterial access and a 2-cm incision above the knee to insert the Endopath device (Ethicon) to locate and clip the GSV side branches. After completion of the proximal anastomosis, the valves were lysed through the distal end of the vein with a flexible valvulotome. Completion cineangiography was performed to confirm side branch occlusion and evaluate the entire reconstruction. The results of this technique were compared with our last 25 in situ bypass grafts done with standard long incisions. RESULTS: In the endoscopic group there was one (4%) minor wound complication (cellulitis). No postoperative arteriovenous fistulas were detected by means of duplex examination, and the average hospital stay was 6.2 +/- 1 days. One graft closed at 9 months as a result of distal vein hyperplasia, but the other grafts have remained patent, with follow-up from 6 to 30 months (mean, 18 months). Patients with the standard in situ bypass grafts had significantly (P < .05) more wound complications (20%) and longer average hospital stay (9.2 +/- 2 days) than the endoscopic group. Patency rates were comparable for both groups. CONCLUSION: These results show that less invasive endoscopic in situ bypass grafting minimizes wound complications and reduces the need for hospitalization without decreasing patency or increasing operative time.

Aged↗
PubMed2001

Eversion technique increases the risk for post-carotid endarterectomy hypertension.

OBJECTIVE: The incidence of postoperative hypertension (HTN) after eversion carotid endarterectomy (e-CEA) was compared with that after standard carotid endarterectomy (s-CEA). METHODS: In a retrospective analysis from January 1998 to January 2000, 217 patients underwent 219 CEAs for symptomatic (68) or asymptomatic (151) high-grade (>80%) carotid artery stenosis by either standard (137) or eversion (82) techniques. The eversion technique involves an oblique transection of the internal carotid artery at the carotid bulb and a subsequent endarterectomy by everting the internal carotid artery over the atheromatous plaque. All procedures were done under general anesthesia, and somatosensory-evoked potentials were used for cerebral monitoring. Patients with s-CEA were compared with those with e-CEA for postoperative hemodynamic instability, carotid sinus nerve block, requirement for intravenous vasodilators or vasopressors, stroke, and death. RESULTS: Patients who underwent e-CEA had a significantly (P <.005) increased postoperative blood pressure and required more frequent intravenous antihypertensive medication (24%), compared with patients having an s-CEA (6%). Furthermore, postoperative vasopressors were required after 10% of s-CEAs, but after none of the e-CEAs. No statistically significant difference was noted in the morbidity or mortality of patients after s-CEA and e-CEA. CONCLUSION: e-CEA is a substantial risk factor for HTN in the immediate postoperative period, when compared with the s-CEA. This difference would be even more remarkable in the absence of antihypertensive medications in the e-CEA group and vasopressors in the s-CEA group. Therefore, particular attention should be focused on diagnosing and controlling postoperative HTN in patients after e-CEA.

Aged↗
PubMed2001

Overt colon ischemia after endovascular aneurysm repair: the importance of microembolization as an etiology.

OBJECTIVE: The purpose of this study was to analyze the incidence, severity, and etiologic factors of the development of colon ischemia after endovascular aortoiliac aneurysm repair (EVAR). METHODS: During the last 9 years we performed 278 elective EVARs using a variety of grafts. To facilitate these repairs, one hypogastric artery (HA) was coil embolized in 109 patients and both HAs were coil embolized in 13 patients. The preprocedural status of the inferior mesenteric, hypogastric, and iliac arteries as well as anatomical characteristics of the abdominal aortic aneurysm were determined arteriographically and by computerized tomographic scans. Postoperative colon ischemia was documented by colonoscopy or operative findings. RESULTS: Colon ischemia occurred in eight patients (2.9%). Three patients with colon ischemia died and had evidence of widespread (cutaneous, renal, small bowel, and/or lower extremity) microembolization. One of these three had a colectomy and microscopic emboli were present. One other patient who required a colectomy also had pathologic evidence of colonic microembolization but survived. Four other patients with colon ischemia were treated conservatively and survived. In one patient, previous colectomy with interruption of mesenteric collaterals may have been a contributory cause of colon ischemia. Of the eight patients with colon ischemia, only one had unilateral HA occlusion, and none had bilateral HA occlusion. The other 121 patients with unilateral and bilateral HA occlusion had no evidence of colon ischemia. CONCLUSIONS: Colon ischemia occurs after EVAR with an incidence approximating that of open repair. Colon ischemia was unrelated to HA interruption. Embolization appears to be a major cause of colon ischemia, although inadequate mesenteric collateral circulation may also play an etiologic role. Mortality with colon ischemia accompanied by widespread embolization was high, whereas colon ischemia without it was often mild and amenable to nonoperative management.

Aged↗
PubMed2001

Increasing incidence of midterm and long-term complications after endovascular graft repair of abdominal aortic aneurysms: a note of caution based on a 9-year experience.

OBJECTIVE: To analyze the late complications after endovascular graft repair of elective abdominal aortic aneurysms (AAAs) at the authors' institution since November 1992. SUMMARY BACKGROUND DATA: Recently, the use of endovascular grafts for the treatment of AAAs has increased dramatically. However, there is little midterm or long-term proof of their efficacy. METHODS: During the past 9 years, 239 endovascular graft repairs were performed for nonruptured AAAs, many (86%) in high-risk patients or in those with complex anatomy. The grafts used were Montefiore (n = 97), Ancure/EVT (n = 14), Vanguard (n = 16), Talent (n = 47), Excluder (n = 20), AneuRx (n = 29), and Zenith (n = 16). All but the AneuRx and Ancure repairs were performed as part of a U.S. phase 1 or phase 2 clinical trial under a Food and Drug Administration investigational device exemption. Procedural outcomes and follow-up results were prospectively recorded. RESULTS: The major complication and death rates within 30 days of endovascular graft repair were 17.6% and 8.5%, respectively. The technical success rate with complete AAA exclusion was 88.7%. During follow-up to 75 months (mean +/- standard deviation, 15.7 +/- 6.3 months), 53 patients (22%) died of unrelated causes. Two AAAs treated with endovascular grafts ruptured and were surgically repaired, with one death. Other late complications included type 1 endoleak (n = 7), aortoduodenal fistula (n = 2), graft thrombosis/stenosis (n = 7), limb separation or fabric tear with a subsequent type 3 endoleak (n = 1), and a persistent type 2 endoleak (n = 13). Secondary intervention or surgery was required in 23 patients (10%). These included deployment of a second graft (n = 4), open AAA repair (n = 5), coil embolization (n = 6), extraanatomic bypass (n = 4), and stent placement (n = 3). CONCLUSION: With longer follow-up, complications occurred with increasing frequency. Although most could be managed with some form of endovascular reintervention, some complications resulted in a high death rate. Although endovascular graft repair is less invasive and sometimes effective in the long term, it is often not a definitive procedure. These findings mandate long-term surveillance and prospective studies to prove the effectiveness of endovascular graft repair.

Aged↗
PubMed2001

Carotid artery stenting: utility of cerebral protection devices.

Neurologic deficits secondary to embolic events have been the most significant concern regarding carotid bifurcation stenting. Experimental studies utilizing human carotid plaques have shown that embolic particles were released from all specimens. In addition, transcranial Doppler studies have confirmed the fact that multiple emboli are released during each case. Preliminary experiences with the use of cerebral protection devices for carotid stenting have shown encouraging results with embolic particles recovered from each case, although these experiences have also revealed some of the down sides of its use. The present article provides the rationale for routine use of these protection devices and also reviews various protection devices, some of which are currently undergoing clinical trials.

Blood Vessel Prosthesis Implantation↗