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Christopher J Kwolek

Publications and source records attributed to Christopher J Kwolek.

14 recordsLinked to original sources

Intermediate results of percutaneous endovascular therapy of femoropopliteal occlusive disease: a contemporary series.

BACKGROUND: Percutaneous endovascular therapy is becoming a primary option for managing infrainguinal occlusive disease. This study examined the results of femoropopliteal percutaneous transluminal angioplasty (PTA) with intermediate (mean, 24 months) follow-up in a contemporary series of patients presenting with critical limb ischemia or claudication. METHODS: Femoropopliteal PTA was performed on 238 consecutive limbs (208 patients) from January 2002 to July 2004. Study end points, including primary patency, assisted patency, and limb salvage (Society of Vascular Surgery reporting standards), were assessed by Kaplan-Meier life-table analysis, and factors predictive of hemodynamic or clinical failure, or both, were evaluated by univariate and multivariate methods. RESULTS: Clinical and demographic features included a mean age, 72 years; male (62%); critical limb ischemia (46%); diabetes mellitus (49%); and renal insufficiency (creatinine >or= 1.5 mg/dL) (29%). Lesions were classified as TransAtlantic Inter-Society Consensus (TASC) A (11%), B (43%), C (41%), and D (5%). PTA was confined to the femoropopliteal segment in 77 patients (33%), and 161 (67%) underwent concurrent interventions in other anatomic locations. Femoropopliteal interventions included angioplasty only in 183 (78%), and the remaining 53 (22%) received at least one stent. Technical success was achieved in 97% of patients, with no deaths and a major morbidity rate of 3%. The 36-month actuarial primary patency was 54.3%, and assisted patency was 92.6% (37 peripheral reinterventions), resulting in a limb preservation rate of 95.4% in all patients regardless of clinical presentation. Interval conversion to bypass surgery occurred in 19 patients (8%). Comparison between critical limb ischemia and claudication revealed a primary patency of 40.8% vs 64.8%, assisted patency of 93.8% vs 92.6%, and limb salvage of 89.7% vs 100%, respectively. Negative predictors of primary patency determined by multivariate analysis included history of congestive heart failure (P = .02) and TASC C/D (P = .02). However, further evaluation of TASC C/D vs A/B revealed an assisted patency of 89.7% vs 94.3% (P = .37) and limb salvage of 94.3% vs 96.4% (P = .58). CONCLUSIONS: Femoropopliteal PTA can be performed with a low perioperative morbidity and mortality. Intermediate primary patency is directly related to TASC classification. Although secondary intervention is often necessary to maintain patency in TASC C/D lesions, these data suggest that it would be appropriate to use PTA as initial therapy for chronic femoropopliteal occlusive disease regardless of clinical classification at presentation or TASC category of lesion severity.

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Stent-graft versus open-surgical repair of the thoracic aorta: mid-term results.

OBJECTIVE: Pivotal and comparative trial data are emerging for stent graft (SG) vs open repair of the thoracic aorta. We reviewed procedure-related perioperative morbidity, mortality, and mid-term outcomes in a contemporary series of patients treated with SG of the thoracic aorta. The data were compared with those of a patient cohort concurrently treated with open surgical repair confined to the descending aorta. METHODS: A review of patients undergoing SG procedures and open surgery of the thoracic aorta from January 1, 1996, to November 30, 2005, was performed from a prospectively compiled database. Study end points included perioperative complications, late survival, freedom from reinterventions, and graft-related complications. Multivariate methods were used to assess variables potentially associated with study end points; late outcomes were compared with actuarial methods. RESULTS: In 105 patients (mean age, 70 years; 66 male [62.9%]) SG repairs were done for 68 degenerative aneurysms (64.7%), 12 penetrating ulcers (11.4%), 15 pseudoaneurysms (14.3%), 9 traumatic tears (8.6%), and 1 acute dissection (0.9%). Mean follow-up was 22 months (range, 0 to 101 months). Eighty-nine (84.8%) SG patients were asymptomatic at presentation and underwent elective repair, whereas 16 (15.2%) presented with acute conditions and underwent urgent repair. Perioperative mortality was 7.6% (8/105), and actuarial survival at 48 months was 54% +/- 7%. The perioperative mortality rate among SG patients treated for degenerative pathology was 10.4% (8/77). Seven (6.7%) of 105 patients experienced spinal cord ischemic complications, including 2 patients with transient paraparesis that resolved by the time of discharge. Reinterventions were performed in 10.5% of patients (11/105), with freedom from reintervention approaching 81% by 48 months. Over the same interval, 93 patients were treated with open-surgical repair for descending thoracic aneurysm (anastomosis cephalad to the celiac axis). Perioperative mortality in the open cohort was 15.1% (14/93; P = .09 vs SG repair), and the 48-month actuarial survival was 64% +/- 6%. The incidence of spinal cord ischemic complications was 8.6% (8/93), including 4 patients with transient paraparesis (P = .44 vs SG repair). Nine patients (9.7%) required surgical reintervention during the follow-up period, with 48-month freedom from reintervention approaching 79% (P = .73 vs SG repair). CONCLUSIONS: Operative mortality was halved with SG, with similar late survival for both cohorts. Reinterventions were required at a nearly identical rate for open repair and SG, and both groups experienced similar rates of spinal cord ischemic complications.

Actuarial Analysis↗

Update on thoracic aortic endovascular grafting using the medtronic talent device.

This article provides a brief update on the current status of the treatment of thoracic aortic pathology using the Medtronic Talent device. Preoperative evaluation and selection criterion along with study design are described for the recently completed Phase II VALOR Trial (Evaluation of the Medtronic AVE Talent Thoracic Stent Graft System for the Treatment of Thoracic Aneurysms). In addition, the results of several recent series for the treatment of degenerative aneurysm and more complex aortic pathology such as transection, rupture and acute and chronic dissection are reviewed.

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Long-term outcomes after endovascular abdominal aortic aneurysm repair: the first decade.

OBJECTIVE: The proper role of endovascular abdominal aortic aneurysm repair (EVAR) remains controversial, largely due to uncertain late results. We reviewed a 12-year experience with EVAR to document late outcomes. METHODS: During the interval January 7, 1994 through December 31, 2005, 873 patients underwent EVAR utilizing 10 different stent graft devices. Primary outcomes examined included operative mortality, aneurysm rupture, aneurysm-related mortality, open surgical conversion, and late survival rates. The incidence of endoleak, migration, aneurysm enlargement, and graft patency was also determined. Finally, the need for reintervention and success of such secondary procedures were evaluated. Kaplan-Meier and multivariate methodology were used for analysis. RESULTS: Mean patient age was 75.7 years (range, 49-99 years); 81.4% were male. Mean follow-up was 27 months; 39.3% of patients had 2 or more major comorbidities, and 19.5% would be categorized as unfit for open repair. On an intent-to-treat basis, device deployment was successful in 99.3%. Thirty-day mortality was 1.8%. By Kaplan-Meier analysis, freedom from AAA rupture was 97.6% at 5 years and 94% at 9 years. Significant risk factors for late AAA rupture included female gender (odds ratio OR, 6.9; P = 0.004) and device-related endoleak (OR, 16.06; P = 0.009). Aneurysm-related death was avoided in 96.1% of patients, with the need for any reintervention (OR, 5.7 P = 0.006), family history of aneurysmal disease (OR, 9.5; P = 0.075), and renal insufficiency (OR, 7.1; P = 0.003) among its most important predictors. 87 (10%) patients required reintervention, with 92% of such procedures being catheter-based and a success rate of 84%. Significant predictors of reintervention included use of first-generation devices (OR, 1.2; P < 0.01) and late onset endoleak (OR, 64; P < 0.001). Current generation stent grafts correlated with significantly improved outcomes. Cumulative freedom from conversion to open repair was 93.3% at 5 through 9 years, with the need for prior reintervention (OR, 16.7; P = 0.001) its most important predictor. Cumulative survival was 52% at 5 years. CONCLUSIONS: EVAR using contemporary devices is a safe, effective, and durable method to prevent AAA rupture and aneurysm-related death. Assuming suitable AAA anatomy, these data justify a broad application of EVAR across a wide spectrum of patients.

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Early outcomes of endovascular versus open abdominal aortic aneurysm repair in the National Surgical Quality Improvement Program-Private Sector (NSQIP-PS).

BACKGROUND: There remains no consensus on the appropriate application of endovascular abdominal aortic aneurysm repair (EVAR). Information from administrative databases, industry-sponsored trials, and single institutions has inherent deficiencies. This study was designed to compare early outcomes of open (OPEN) versus EVAR in a contemporary (2000 to 2003) large, multicenter prospective cohort. METHODS: Fourteen academic medical centers contributed data to the National Surgical Quality Improvement Program-Private Sector (NSQIP-PS), which ensures uniform, comprehensive, prospective, and previously validated data entry by trained, independent nurse reviewers. A battery of clinical and demographic features was assessed with multivariate analysis for association with the principal study end points of 30-day operative mortality and morbidity. RESULTS: One thousand forty-two patients underwent elective infrarenal abdominal aortic aneurysm (AAA) repairs: 460 EVAR and 582 OPEN. EVAR patients were older (74 vs 71 years, P < .0001), included more men (84.6% vs 79.6%, P < .05), and had a higher incidence of chronic obstructive pulmonary disease (25.4% vs 17.9%, P < .01). EVAR resulted in significantly reduced overall morbidity (24% vs 35%, P < .0001) and hospital stay (4 vs 9 days, P < .0001). Cardiopulmonary and renal function-related comorbidities had the expected significant impact on mortality for both procedures at univariate analysis ( P < .05). While crude mortality rates between EVAR and OPEN did not differ significantly (2.8% vs 4.0%) ( P = 0.32). After multivariate analysis, correlates of operative mortality included OPEN (odds ratio [OR], 2.44; 95% confidence interval [CI], 1.03 to 5.78; P < .05), advanced age (OR, 1.11; P < .001), history of angina (OR, 5.54; P < .01), poor functional status (OR, 5.78; P < .001), history of weight loss (OR, 7.42; P < .01), and preoperative dialysis (OR, 51.4; P < .0001). EVAR also compared favorably to OPEN (OR, 2.14; 95% CI, 1.58 to 2.89; P < .0001) for overall morbidity. CONCLUSION: Significant morbidity accompanies AAA repair, even at major academic medical centers. These data strongly endorse EVAR as the preferred approach in the presence of significant cardiopulmonary or renal comorbidities, or poor preoperative functional status.

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Safety and efficacy of reoperative carotid endarterectomy: a 14-year experience.

BACKGROUND: Reoperative carotid endarterectomy (CEA) is an accepted treatment for recurrent carotid stenosis. With reports of a higher operative morbidity than primary CEA and the advent of carotid stenting, catheter-based therapy has been advocated as the primary treatment for this reportedly "high-risk" subgroup. This study reviews a contemporary experience with reoperative CEA to validate the high-risk categorization of these patients. METHODS: From 1989 to 2002, 153 consecutive, isolated (excluding CEA/coronary artery bypass graft and carotid bypass operations) reoperative CEA procedures were reviewed. Clinical and demographic variables potentially associated with the end points of perioperative morbidity, long-term durability, and late survival were assessed with multivariate analysis. RESULTS: There were 153 reoperative CEA procedures in 145 patients (56% men, 36% symptomatic) with an average age of 69 +/- 1.3 years. The average time from primary CEA (68% primary closure, 23% prosthetic, 9% vein patch) to reoperative CEA was 6.1 +/- 0.4 years (range, 0.3 to 20.4 years). At reoperation, patch reconstruction was undertaken in 93% of cases. The perioperative stroke rate was 1.9%, with no deaths or cardiac complications. Other complications included cranial nerve injury (1.3%) and hematoma (3.2%). Average follow-up after reoperative CEA was 4.4 +/- 0.3 years (range, 0.1 to 12.7 years), with an overall total stroke-free rate of 96% and a restenosis rate (>50%) by carotid duplex of 9.2%. Among variables assessed for association with restenosis after reoperative CEA, only younger age was found to be significant (66 +/- 2.5 years vs 70 +/- 0.7 years, P < .05). The all-cause long-term mortality rate was 29%. Multivariate analysis of long-term survival identified diabetes mellitus as having a negative impact (hazard ratio, 3.4 +/- 0.3, P < .05) and lipid-lowering agents as having a protective effect (hazard ratio, 0.42 +/- 0.4, P < .05) on survival. CONCLUSION: Reoperative CEA is a safe and durable procedure, comparable to reported standards for primary CEA, for long-term protection from stroke. These data do not support the contention that patients who require reoperative CEA constitute a "high-risk" subgroup in whom reoperative therapy should be avoided.

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Contemporary results of angioplasty-based infrainguinal percutaneous interventions.

INTRODUCTION: Although lower-extremity bypass grafting has been the gold standard for infrainguinal revascularization, endovascular therapies have been increasingly applied to avoid operative morbidities. This study addresses the initial results of an implementation of infrainguinal percutaneous transluminal angioplasty (PTA) performed by vascular surgeons to treat lower-extremity ischemia. METHODS: From January 2002 to July 2003, 95 consecutive patients presenting with the spectrum of lower-extremity ischemic manifestations, in whom infrainguinal PTA was the initial choice of treatment, were assessed for treatment efficacy by clinical and noninvasive evaluation. Study end points of angiographic, hemodynamic, and clinical successes (Society of Vascular Surgery reporting standards) were recorded, and variables associated with ischemic category improvement were analyzed by univariate and multivariate analysis. During the same study interval, 87 patients underwent bypass grafting (not further considered). RESULTS: PTA was used to treat 100 limbs in 95 consecutive patients: 63 limbs (63%) had femoropopliteal PTA, 17 limbs (17%) had tibioperoneal PTA, and 20 limbs (20%) had multilevel PTA. Tissue-threatening ischemia was present in 47% of patients, and 53% were treated for claudication. Complications (no mortality) included one myocardial infarction (1%) and two access site hematomas (2%). Angiographic and hemodynamic success (a .10 increase in ankle-brachial index) was obtained in 97% and 90% of the treated limbs, respectively. With a mean follow-up of 14 months, clinical success was obtained in 85% of the treated limbs, and limb salvage for critical ischemia was achieved in 75% (30/40 limbs). Of the PTA failures, five patients (5%) underwent bypass grafting, and five patients (5%) underwent major amputation because of no further reconstructive options or extensive necrosis. Insulin-dependent diabetes mellitus (risk ratio [RR], 3.1; 95% confidence interval [CI], 1.1 to 8.7, P = .02), poor runoff into the foot (RR, 3.7; 95% CI, 1.6 to 8.6, P = .001), and renal insufficiency (serum creatinine >1.5 mg/dL) (RR, 3.7; 95% CI, 1.8 to 7.6, P = .001) were predictive of PTA failure. CONCLUSION: Infrainguinal percutaneous transluminal angioplasty for lower-extremity ischemia is feasible, safe and provides acceptable hemodynamic and clinical results. PTA will become the initial treatment for most patients requiring lower-extremity revascularization.

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Surveillance venous duplex is not clinically useful after total joint arthroplasty when effective deep venous thrombosis prophylaxis is used.

The early detection of deep venous thrombosis (DVT) and treatment with systemic anticoagulation to prevent pulmonary embolism (PE) are essential in the management of patients undergoing total joint arthroplasty (TJA). However, improvements in prophylactic measures have significantly decreased the occurrence of DVT in these patients. The purpose of this study was to determine whether routine postoperative duplex surveillance for DVT remains clinically useful. The medical records of all patients undergoing total knee or total hip arthroplasty between October 1997 and January 2002 at a University Hospital and its Veterans Affairs (VA) affiliate were reviewed. The type of operation and occurrence of complications (e.g., DVT, PE, and hemorrhage) were noted. All patients were treated postoperatively with both enoxaparin 30 mg b.i.d. and bilateral lower extremity sequential compression devices (SCDs). A venous duplex scan was performed prior to discharge. Three hundred ninety-eight patients underwent 441 TJAs for 149 hips and 292 knees. The average age was 65 years (range, 23-95). Venous duplex scans were performed within 1 week (median, 4 days) of operation. Initial inpatient scans revealed acute, ipsilateral DVT in five patients (1.3%). Three patients experienced documented PE-one as an inpatient and two after hospital discharge; both outpatients had negative inhospital duplex scans. One of the 398 patients did not have a duplex scan as an inpatient and returned 6 weeks later with a popliteal DVT. Complications included one upper gastrointestinal hemorrhage, and one patient died postoperatively of unknown causes. These data demonstrate that routine postoperative venous duplex scans rarely found DVT (5 of 398 patients) after TJA when effective prophylaxis was used. Furthermore, surveillance scanning did not enable reliable prediction of PE. Therefore, we conclude that postoperative inpatient surveillance duplex scans for DVT provide very minimal benefit and that a routine screening program is not clinically useful for patients managed with effective DVT prophylaxis.

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Preservation of renal function with surgical revascularization in patients with atherosclerotic renovascular disease.

OBJECTIVE: Clinical and anatomic factors predictive of a favorable response to renal revascularization performed for renal function salvage remain poorly defined. To clarify decision making in such patients we reviewed a contemporary experience of surgical renal artery revascularization (RAR) performed primarily for preservation of renal function. METHODS: Between June 1990 and March 2001 (ensuring 1 year minimum follow-up), 96 patients with renal insufficiency (serum creatinine [Cr] concentration >or=1.5 mg/dL) and hypertension underwent RAR for preservation of renal function. Study end points included early and late renal function response, progression to dialysis dependence, and long-term survival. Variables potentially associated with these end points were assessed with univariate analysis, Cox regression analysis, and logistic regression analysis, and survival was assessed with the Kaplan-Meier method. RESULTS: Perioperative failure of RAR occurred in 3 patients (3%), with perioperative mortality in 4 patients (4.1%); thus 92 patients were available for long-term follow-up (mean, 39 months). Mean patient age was 70 +/- 9 years with a mean baseline Cr of 2.6 mg/dL (range, 1.5-7.8 mg/dL). Operative management consisted of aortorenal bypass in 38% of patients, extraanatomic bypass in 38% of patients, and endarterectomy in 24% of patients; 32% of patients required combined aortic revascularization and RAR, and 27% underwent bilateral RAR. At hospital discharge renal function had improved (20% decrement in Cr) in 41 (43%) patients, including 7 patients who were removed from dialysis; remained unchanged in 40 (41%) patients; and declined (20% increase in Cr) in 15 (16%) patients. At last follow-up renal function was either improved or unchanged in 72% of patients. Predictors of a favorable response to RAR at last follow-up included stable Cr at hospital discharge (odds ratio [OR], 7.1; 95% confidence interval [CI], 2.5-21.8; P =.0004) and decreased Cr at hospital discharge (OR, 16; 95% CI, 1.6-307.8; P <.0001); bilateral renal artery repair (OR, 3.1; 95% CI, 0.9-10.6; P =.07) approached clinical significance. Predictors of worsened excretory function at last follow-up included decline of renal function at hospital discharge (OR, 28.9; 95% CI, 5.0-165.4; P =.0002), intervention to treat unilateral renal artery stenosis (OR, 3.8; 95% CI, 0.8-16.6; P =.05), and level of baseline Cr (OR, 3.0; 95% CI, 1.0-4.0; P =.04). Progression to dialysis occurred in 16 (17%) patients. Dialysis-free survival at 5 years was 50%, and overall actuarial survival at 5 years was 59%. Predictors of progression to dialysis during follow-up included treatment of complete renal artery occlusion (OR, 6.2; 95% CI, 1.3-29.5; P =.02), early failure of RAR (OR, 3.1; 95% CI, 0.7-14.2; P =.04) and baseline Cr (OR, 2.9; 95% CI, 1.3-6.1; P =.006). CONCLUSION: Long-term clinical success in the preservation of renal function, noted in 70% of patients, can be predicted by the initial response to RAR and by anatomic factors, in particular, bilateral repair. While extreme (mean Cr >or=3.2 mg/dL) renal dysfunction generally is predictive of poor long-term outcome, a subset of patients will experience favorable results, even to the extent of rescue from dialysis. These results may facilitate clinical decision making in the application of RAR for renal function salvage.

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Durability of aortouniiliac endografting with femorofemoral crossover: 4-year experience in the Evt/Guidant trials.

OBJECTIVES: We evaluated mid-term results of the multicenter EVT/Guidant aortouniiliac endograft (AI) trial and ascertained the durability of this endovascular technique in patients unable to undergo standard bifurcated endografting. METHODS: From November 1996 to December 1998, 121 patients were enrolled to receive the AI device on the basis of complex iliac artery anatomy contraindicating bifurcated endografting. Clinical data were centrally collected, and radiographic data were evaluated by core facility. RESULTS: AI placement was technically successful in 113 of 121 patients. At operation, patients who underwent AI had significantly more arrhythmias, congestive heart failure, and peripheral occlusive disease (P <.05) compared with patients who underwent open aneurysmorrhaphy in the EVT/Guidant trials, indicating comorbid features in this anatomic cohort. Distal AI attachment was performed to the external iliac artery in 40 (36%) patients. Median follow-up was 38 months. In the AI group, overall aneurysm diameter decreased over the duration of study from 54.4 +/- 9.6 mm to 44.4 +/- 16.4 mm (P =.004). At 24 and 36 months after repair, reduction in aneurysm size was associated with absence of endoleak (P =.003 and P =.008, respectively). Aneurysms shrunk or remained stable in 109 (96.5%) patients. Endoleak was identified in 52.3% of patients at discharge, and at follow-up in 30.9% at 1 year, 34.8% at 2 years, 28.6% at 3 years, and 30.4% at 4 years. Type II endoleak predominated. Leak from failure to completely occlude contralateral iliac flow accounted for 8 of 58 endoleaks (13.8%) at discharge. Sixteen patients (14.2%) underwent postoperative endoleak treatment; in one of these patients open conversion was necessary at 20 months. Post-procedure thigh or buttock claudication developed in 16 patients (14.2%). Thirteen patients (81.3%) had either distal attachment in the external iliac artery or contralateral type IIA occlusion. Fifteen patients (13.3%) required intervention because of reduced limb flow; one of these patients underwent open conversion at 27 months, and another underwent axillofemoral grafting at 28 months. Device migration was confirmed in 2 (1.8%) patients, without current clinical sequelae. Whereas no femorofemoral graft thromboses occurred, graft infection developed in 3 patients (2.6%). During follow-up, aneurysm in 2 patients ruptured. Late death occurred in 41 patients (36.3%). Twenty-four patients (58.5%) died of cardiopulmonary disease; one death was endograft-related after aneurysm rupture; and one death was related to femorofemoral bypass infection. Actuarial survival was 78.4% (95% confidence interval [CI], 71%-86%) at 2 years and 63.4% (95% CI, 54%-73%) at 4 years. CONCLUSIONS: In patients with significant comorbid conditions and complex iliac anatomy unfavorable for bifurcated endografting, AI with femorofemoral bypass grafting is safe and effective. In most patients this endovascular option provides satisfactory mid-term results.

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Endovascular repair of external iliac artery occlusion after hip prosthesis migration.

PURPOSE: To report emergent endovascular intervention to restore lower extremity arterial patency after migration of a hip prosthesis caused thrombosis of the external iliac artery (EIA). CASE REPORT: Nine months following left hip revision arthroplasty, a 66-year-old woman presented to the Emergency Department with the complaints of an acutely painful left lower extremity for over 6 hours. Imaging showed the metallic acetabular portion of the hip prosthesis in the iliac fossa, with severe external compression of the EIA. After thrombolysis to remove clot from the EIA, an 8x60-mm self-expanding Smart stent was deployed in the left EIA from a contralateral access. The procedure was successful, and the patient was discharged. An infected wound from a compartment fasciotomy delayed revision of the hip prosthesis. Nine weeks after stenting, the patient returned with a cold, pulseless left limb; a femorofemoral bypass was constructed to restore perfusion. CONCLUSIONS: While stent placement restored flow for 9 weeks after the initial ischemic event, the recurrent thrombosis could have been prevented by earlier revision of the migrated prosthesis.

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Carotid blowout with infection: management with endovascular and open vascular approaches--a case report.

The management of patients with head and neck cancer can be complicated by massive carotid artery hemorrhage, often requiring ligation owing to the emergent conditions and scarring from previous surgery and radiation. A case of emergent endovascular management of carotid artery hemorrhage in a patient treated for pharyngeal carcinoma is described. Hemorrhage was controlled, but on follow-up the patient developed a carotid-cutaneous fistula with exposure of the coils. Further management required the use of autogenous vein to replace the involved vessels. This case demonstrates that endovascular control of carotid hemorrhage can be successful, but close follow-up is necessary to identify potential subsequent complications.

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