PubMed Health⌕ Search

Biomedical subjects

W Anthony Lee

Publications and source records attributed to W Anthony Lee.

At least 19 recordsLinked to original sources
PubMed2007

Perioperative differences between endovascular repair of thoracic and abdominal aortic diseases.

BACKGROUND: With the US Food and Drug Administration approval of the TAG thoracic device, more thoracic pathologies are being treated using endovascular techniques. Although endovascular abdominal and thoracic aortic repairs have some apparent similarities, there are substantive anatomic, pathologic, and technical differences that could impact perioperative outcomes. The purpose of this study is to identify these differences. METHODS: During a 5-year period, 121 endovascular thoracic aortic repairs (TEVAR) and 450 abdominal aortic repairs (EVAR) were performed at a single institution. Preoperative, intraoperative, and early postoperative data were prospectively collected and retrospectively reviewed. Aggregate outcome measures were compared between the two cohorts, with statistical significance achieved at P < .05. RESULTS: The mean age of patients undergoing EVAR was 72.8 +/- 8.3 compared with 68.3 +/- 13.9 for TEVAR (P = .02). More women underwent TEVAR (30.6% vs 11.1%, P < .001). Aneurysms undergoing TEVAR were larger than those for EVAR (62.0 mm vs 58.3 mm, P = .01). Intraoperatively, EVAR required 26.2 minutes of fluoroscopy compared with 22.1 minutes for TEVAR (P < .001). The amount of contrast used was higher in TEVAR (133.6 mL vs 93.6 mL, P < .001). The mean procedure times were 164 minutes for EVAR and 115 minutes for TEVAR (P < .001). Iliac conduits were required in 46 patients (10.2%) undergoing EVAR, and in 24 (19.8%) undergoing TEVAR (P = .007). The 30-day or in-hospital mortality was 2.0% for EVAR and 5.0% for TEVAR (P = NS). The median length of stay was longer for TEVAR (3 days vs 2 days, P =.034). There were 54 postoperative complications in 36 TEVAR patients (29.8%), including 13 neurologic (10.7%), 8 renal (6.6%), 7 pulmonary (5.8%), 6 ischemic (5.0), and 5 (4.1%) hemorrhagic events. Among the EVAR group, 136 (30.2%) patients had postoperative complications, which included 45 ischemic (10.0%), 34 wound (7.6%), 22 renal (4.9%), 12 cardiac (2.7%), 8 pulmonary (1.8%), 5 gastrointestinal (1.1%), and 4 neurologic (0.9%) events. CONCLUSIONS: A relatively higher proportion of women underwent TEVAR than EVAR, and this was reflected in the greater need for iliac conduits to accommodate the larger delivery catheters of the thoracic devices. Intraoperative imaging techniques were also different, and TEVAR required higher contrast volumes despite shorter overall procedure times. The incidence of strokes and spinal cord ischemia was also higher during TEVAR. Despite apparent similarities of devices and techniques, EVAR and TEVAR are fundamentally different procedures with different perioperative outcomes.

Adult↗
PubMed2006

Sheath-assisted controlled deployment technique for Excluder bifurcated main body.

The W. L. Gore Excluder bifurcated device uses a single-action deployment mechanism with an expanded polytetrafluoroethylene string that is stitched to an outer jacket constraining the nitinol self-expanding stent-graft. Under certain anatomic conditions of the proximal neck, the deployment angle of the proximal stent-graft can be difficult to predict and result in the device being seated caudal to the intended landing site just below the lowermost renal artery. This article describes a technique of controlled deployment of the Excluder device where the top of the main bifurcated device is "flowered" by slowly pulling the deployment string while being buttressed by an introducer sheath to prevent premature deployment and allow longitudinal positioning of the device. This technique could be used when a more gradual deployment of the Excluder device is desired in angulated or short proximal necks.

Angioplasty↗
PubMed2006

Late type III endoleak from graft erosion of an Excluder stent graft: a case report.

We report a case of a late type III endoleak from a hole in the expanded polytetrafluoroethylene graft material of an Excluder bifurcated stent-graft approximately 12 months after implantation. The endoleak was successfully repaired by relining the defect site with an Excluder iliac limb. To our knowledge, this is the first reported case of late graft-material related Type III endoleak involving the Excluder device.

Aged↗
PubMed2006

Outcome after hypogastric artery bypass and embolization during endovascular aneurysm repair.

BACKGROUND: Multiple strategies have been devised to extend the applicability of endovascular aneurysm repair (EVAR) in patients with common iliac artery (CIA) aneurysms. This study was designed to examine outcome in patients undergoing EVAR with either hypogastric artery embolization or common iliac artery bifurcation advancement by hypogastric bypass. METHODS: A retrospective review of all patients undergoing EVAR since the inception of our program (1997-2006) was performed. Data were prospectively collected in an EVAR registry. Patients with large common iliac artery aneurysms (> or = 20 mm) and patent hypogastric arteries not amenable to a cuff or "bell bottom" technique were treated with coil embolization (EMBO) and/or hypogastric revascularization (BYPASS). The perioperative and mid-term outcomes were compared with the larger group of patients undergoing EVAR that did not require either treatment (CTRL). Bilateral common iliac artery aneurysms were treated with unilateral coil embolization and contralateral bypass. RESULTS: Common iliac artery aneurysms were present in 137 (31%) of the 444 patients undergoing EVAR, but only 57 (42%) of 137 required direct management. This included hypogastric artery embolization alone (EMBO) in 31 or hypogastric artery revascularization (BYPASS) in 26, with and without contralateral embolization (both revascularization/embolization in 46%). The procedure length (CTRL, 159 +/- 72 minutes; EMBO, 153 +/- 39 minutes; BYPASS, 283 +/- 75 minutes) and estimated blood loss (CTRL, 251 +/- 313 mL; EMBO, 233 +/- 158 mL; BYPASS, 400 +/- 287 mL) were significantly greater (P < .05) in the BYPASS group. The incidence of any postoperative complication (CTRL, 26%; EMBO, 68%; BYPASS, 54%), any ischemic complication (CTRL, 6%; EMBO, 55%; BYPASS, 27%), and new-onset buttock claudication (CTRL, 3%; EMBO, 39%; BYPASS, 27%) were all significantly greater in the BYPASS and EMBO group relative to the control (CTRL) group (n = 387). The incidence of new-onset buttock claudication ipsilateral to the hypogastric bypass was 4%; the balance of the new onset claudication in the BYPASS group was due to the contralateral embolization. The primary hypogastric artery bypass patency was 91 +/- 11% (SE) at 36 months by life-table analysis. CONCLUSIONS: Despite its increased complexity, hypogastric artery bypass is an excellent alternative to embolization in terms of patency and freedom from ischemic symptoms for patients with large common iliac artery aneurysms undergoing EVAR.

Aged↗
PubMed2006

Laparoscopic repair of a type II endoleak.

A 72-year-old male underwent an uncomplicated endovascular repair of a 6.1-cm infrarenal abdominal aortic aneurysm. Routine follow-up at 18 months postoperatively revealed the presence of a type II endoleak, and that the aneurysm had increased in size. The endoleak was repaired by laparoscopic ligation of the inferior mesenteric artery. A postoperative computerized tomography scan revealed cessation of flow through the inferior mesenteric artery. The patient tolerated the procedure well and was discharged home on the same day.

Aged↗
PubMed2005

Endovascular stent graft repair of abdominal aortic aneurysms after liver transplantation.

It is estimated that 1.7% of orthotopic liver transplant recipients will develop abdominal aortic aneurysms (AAAs) after transplantation. It has been observed that these aneurysms expand faster in transplant recipients; therefore, aggressive surveillance for AAAs in transplant recipients is required. Endovascular aneurysm repair is rapidly becoming the standard of care, especially in patients with previous abdominal surgery and other significant comorbidities. This article describes our experience with AAAs in orthotopic liver transplant recipients treated successfully by endovascular stent graft repair.

Aged↗
PubMed2004

Genomic and proteomic determinants of outcome in patients undergoing thoracoabdominal aortic aneurysm repair.

Thoracoabdominal aortic aneurysm repair, with its requisite intraoperative mesenteric ischemia-reperfusion, often results in the development of systemic inflammatory response syndrome, multiorgan dysfunction syndrome (MODS), and death. In the present study, an adverse clinical outcome following thoracoabdominal aortic aneurysm repair was identified by blood leukocyte genomic and plasma proteomic responses. Time-dependent changes in the expression of 146 genes from blood leukocytes were observed (p < 0.001). Expression of 138 genes (p < 0.001) and the concentration of seven plasma proteins discriminated between patients who developed MODS and those who did not, and many of these differences were evident even before surgery. These findings suggest that changes in blood leukocyte gene expression and plasma protein concentrations can illuminate pathophysiological processes that are subsequently associated with the clinical sequelae of systemic inflammatory response syndrome and MODS. These changes in gene expression and plasma protein concentrations are often observed before surgery, consistent with either a genetic predisposition or pre-existing inflammatory state.

Aged↗
PubMed2004

Hypogastric artery bypass to preserve pelvic circulation: improved outcome after endovascular abdominal aortic aneurysm repair.

OBJECTIVE: This study was carried out to compare the functional outcomes after hypogastric artery bypass and coil embolization for management of common iliac artery aneurysms in the endovascular repair of aortoiliac aneurysms (EVAR). METHODS: Between 1996 and 2002, 265 patients underwent elective or emergent EVAR. Data were retrospectively reviewed for 21 (8%) patients with iliac artery aneurysms 25 mm or larger that involved the iliac bifurcation. Patients underwent hypogastric artery bypass (n = 9) or coil embolization (n = 12). Interviews about past and current levels of activity were conducted. A disability score (DS) was quantitatively graded on a discrete scale ranging from 0 to 10, corresponding to "virtually bed-bound" to exercise tolerance "greater than a mile." Worsening or improvement of symptoms was expressed as a difference in DS between two time points (-, worsening; +, improvement). RESULTS: There was no difference in age (72.6 +/- 7.3 years vs 73.1 +/- 6.4 years), sex (male-female ratio, 8:1 vs 11:1), abdominal aortic aneurysm size (60.1 +/- 5.9 mm vs 59.3 +/- 7.0 mm), or number of preoperative comorbid conditions (1.9 +/- 0.8 vs 2.1 +/- 0.8) between hypogastric bypass and coil embolization groups, respectively. Mean follow-up was shorter after hypogastric bypass (14.8 vs 20.5 months; P <.05). There was no difference in the mean overall baseline DS between the bypass and the embolization groups (8.0 vs 7.8). Six (50%) of the 12 patients with coil embolization reported symptoms of buttock claudication ipsilateral to the occluded hypogastric artery. No symptoms of buttock claudication were reported after hypogastric bypass (P <.05). There was a decrease in the DS after both procedures; however, coil embolization was associated with a significantly worse DS compared with hypogastric artery bypass (4.5 vs 7.3; P <.001). In 4 (67%) of 6 patients with claudication after coil embolization symptoms improved, with a DS of 5.4 at last follow-up. This was significantly worse than in patients undergoing hypogastric artery bypass, with a DS of 7.8 at last follow-up (P <.001). There was no difference between the groups in duration of procedure, blood loss, length of hospital stay, morbidity, or mortality (0%). CONCLUSIONS: Hypogastric artery bypass to preserve pelvic circulation is safe, and significantly decreases the risk for buttock claudication. Preservation of pelvic circulation results in significant improvement in the ambulatory status of patients with common iliac artery aneurysms, compared with coil embolization.

Aged↗
PubMed2004

Perioperative outcomes after open and endovascular repair of intact abdominal aortic aneurysms in the United States during 2001.

OBJECTIVE: Small patient numbers, mixed data from clinical trials, and longitudinal series representing institutional learning curves have characterized previous studies of early outcomes after endovascular abdominal aortic aneurysm (AAA) repair. We compared the perioperative outcomes of endovascular and open surgical AAA repair in an unselected sample of patients in a single calendar year using a national administrative database. METHODS: The 2001 National Inpatient Sample database was retrospectively reviewed. This database represents 20% of all-payer stratified sample of non-federal US hospitals. Patients older than 49 years were identified by primary diagnostic codes (International Classification of Disease, ninth revision [ICD-9], 441.4, intact, nonruptured AAA) and procedure codes (ICD-9 38.44 for open, 39.71 for endovascular repair). Patient demographic data (age, sex), comorbid conditions (ICD-9 coded), inpatient complications (ICD-9 coded), length of stay, final discharge disposition (home vs institution vs death), and hospital charges were examined with univariate and multivariate analyses. RESULTS: In calendar year 2001, 7172 patients underwent either open (64%) or endovascular (36%) repair of intact, nonruptured AAAs. Despite comparable rates of preoperative comorbid conditions and a greater proportion of octogenarians (23% vs 16%%; P =.0001), morbidity (18% vs 29%; P =.0001) and mortality (1.3% vs 3.8%; P =.0001) were significantly lower for endovascular repair than for open repair. The median length of stay (2 vs 7 days; P =.0001) and the rate of discharge to an institutional facility versus home (6% vs 14%; P =.0001) were also much lower in the endovascular group than in the open repair group. At multivariate analysis, open AAA repair and age older than 80 years were strong independent predictors (P =.0001 for all) for death (open repair: odds ratio [OR], 3.3; 95% confidence interval [CI], 2.3-4.9; age: OR, 14.2; 95% CI, 3.5-58.1), complications (open repair: OR, 1.9; 95% CI, 1.7-2.1; age: OR, 1.9; 95% CI, 1.5-2.5), and not being discharged to home (open repair: OR, 3.4; 95% CI, 2.9-4.1; age: OR, 12.0; 95% CI, 7.0-20.4). Mean hospital charges were significantly greater (difference, $3337; P =.0009) for endovascular repair than for open repair. Extrapolated to the total number of endovascular AAA repairs performed during the single 2001 calendar year, this resulted in a staggering $50.3 million in additional hospital charges. CONCLUSIONS: Endovascular repair of intact AAAs results in a significantly lower number of complications and deaths, shorter hospital stay, and improved likelihood of discharge to home, even in older patients, when compared with open surgical repair. These impressive gains in clinical outcome, however, are achieved at similarly impressive increases in health care costs.

Aged↗
PubMed2004

Outcome after autogenous brachial-axillary translocated superficial femoropopliteal vein hemodialysis access.

OBJECTIVE: The optimal configuration for patients with "complex" or "tertiary" hemodialysis access needs remains undefined. This study was designed to examine the utility of the autogenous brachial-axillary translocated superficial femoropopliteal vein access (SFV ACCESS) in this subset of patients. METHODS: Patients presenting for permanent hemodialysis access without a suitable upper extremity vein for autogenous access identified by duplex ultrasound mapping and those with repeated prosthetic access failures were considered candidates for SFV ACCESS. Ankle-brachial indices were obtained, and duplex scanning of the superficial femoropopliteal and saphenous veins was performed. Patients deemed candidates for SFV ACCESS also underwent preoperative upper extremity arteriography and venography. A retrospective review of the complete medical record was performed, and a follow-up telephone or personal interview was conducted. RESULTS: Thirty patients (mean age +/- SD, 54 +/- 15 years; male, 33%; white, 37%; with diabetes, 50%; obese, 21%) underwent SFV ACCESS among approximately 650 access-related open surgical procedures during the study period. The patients had been receiving dialysis for 4 +/- 5 years (range, 0-24 years), and had 3 +/- 3 (range, 0-17) prior permanent accesses, whereas 90% were actively dialyzed through tunneled catheters. In-hospital 30-day mortality was 3%, and the hospital length of stay was 7 +/- 7 days. Fifty-seven percent of the patients experienced some type of perioperative complication, and 38% required a remedial surgical procedure. Hand ischemia developed in 43% of the patients (severity grade: 1, 10%; 2, 7%; 3, 27%), and a distal revascularization, interval ligation was performed in all those with grade 3 ischemia. Thigh wound complications or hematomas developed in 23% of the patients, and arm wound complications or hematomas developed in 17%. The incidence of thigh wound complications was significantly greater (57% vs 9%; P =.03) in obese patients, but the other perioperative complications analyzed could not be predicted on the basis of age, gender, or comorbid conditions. The SFV ACCESS was cannulated 7 +/- 1 weeks postoperatively. The primary, primary assisted, and secondary patency rates were 96% +/- 4%, 100% +/- 0%, and 100% +/- 0%, respectively, at 6 months; 79% +/- 8%, 91% +/- 6%, and 100% +/- 0%, respectively, at 12 months; and 67% +/- 13%, 86% +/- 9%, and 100% +/- 0%, respectively, at 18 months (life table analysis; % +/- SE). CONCLUSIONS: The intermediate term functional patency rate after SFV ACCESS is excellent, although the magnitude of the procedure and the complication rate are significant. SFV ACCESS should only be considered in patients with limited access options.

Arteriovenous Shunt, Surgical↗
PubMed2004

Impact of endovascular repair on early outcomes of ruptured abdominal aortic aneurysms.

OBJECTIVE: Our purpose was to examine the impact of the introduction of endovascular treatment on the early outcomes of ruptured abdominal aortic aneurysms (AAAs) during 2 consecutive time periods at a single institution. METHODS: The hospital records of a single tertiary care center from 1997 to 2004 were retrospectively reviewed, and 36 consecutive patients who underwent treatment for acute ruptured AAA were identified. They were divided into 19 (53%) patients who were all treated with conventional open surgery from 1997 to 2001 (early) and 17 (47%) patients who were treated either with open (n = 4, 24%) or endovascular (n = 13, 76%) methods from 2002 to 2004 (late). All endovascular repairs were performed with commercially available bifurcated devices. Outcome measures included death, major complications, disposition at discharge (home or extended care facility), procedure time, blood loss, and hospital length of stay. RESULTS: Age, sex, and AAA size were similar between the 2 groups. Perioperative mortality in the early and late periods were 37% versus 12%, respectively (P =.13); rates of major complications were 84% versus 65%, respectively (P =.26); and discharge to home rather than extended care facility was 32% versus 59%, respectively (P =.18). Median procedure times (275 vs 149 minutes, P <.01), blood loss (3800 vs 138 mL, P <.0001), and length of stay (18 vs 6 days, P <.05) were all higher during the early period than in the late period. CONCLUSIONS: This preliminary study suggests that introduction of endovascular therapies may be potentially beneficial in the overall treatment scheme of patients with ruptured AAAs. However, longer follow-up and larger cohorts are needed to better establish its feasibility and efficacy compared with conventional open surgical repair.

Aged↗
PubMed2003

Morbidity with retroperitoneal procedures during endovascular abdominal aortic aneurysm repair.

PURPOSE: Retroperitoneal iliac procedures can enable successful endovascular repair of abdominal aortic aneurysm (AAA) in patients who otherwise would not be anatomically eligible. The purpose of this study was to determine perioperative outcome with adjunctive retroperitoneal procedures compared with standard bilateral femoral exposure. METHODS: Between August 1997 and November 2002, 164 patients underwent elective endovascular AAA repair at a single university medical center. Anatomic, demographic, and early postoperative outcome data gathered prospectively were analyzed. Thirty-two patients (20%) underwent 38 separate adjunctive retroperitoneal procedures. Indications included small external iliac arteries (16 of 32 patients; 50%) and concomitant iliac aneurysm that precluded fixation of the endograft limbs in the common iliac arteries (16 of 32 patients; 50%). The 38 procedures consisted of 8 iliac conduits only, 14 iliac conduits with iliofemoral bypass grafts, and 16 hypogastric revascularization procedures. Data for the study patients were compared with data for 132 patients who underwent endovascular AAA repair through femoral incisions. Primary end points were hospital length of stay, and early morbidity and mortality. RESULTS: Retroperitoneal procedures enabled an additional 14% of patients with AAA to undergo endovascular techniques. However, there was a significantly higher proportion of women and patients at high risk for anesthesia (American Society of Anesthesiologists class IV or higher) in the group who underwent retroperitoneal procedures. On average, retroperitoneal procedures were associated with 2.6-fold greater blood loss, 82% longer procedure time, 1.5 days additional hospital stay, and 1.8-fold higher rate of perioperative complications, compared with endovascular AAA repair with femoral exposure alone. In contrast, early mortality was similar in the two groups. CONCLUSION: Adjunctive retroperitoneal procedures during endovascular AAA repair are associated with increased risk for complications and longer hospital length of stay, compared with AAA repair with standard femoral exposure only. They do not, however, increase early mortality, even in patients at high risk, and enable a larger subset of patients with AAA to undergo endovascular repair.

Aged↗
PubMed2003

Transient paraplegia after stent grafting of a descending thoracic aortic aneurysm treated with cerebrospinal fluid drainage.

We present a case of descending thoracic aortic aneurysm repair using an endovascular stent graft, complicated by postoperative paraplegia, which was successfully treated by placing a spinal drain. The case highlights the importance of the concept of collateral flow to the spinal cord and of choosing an anesthetic technique that allows immediate postoperative evaluation of lower extremity neurologic function.

Aged↗
PubMed2002

A technique for combined hypogastric artery bypass and endovascular repair of complex aortoiliac aneurysms.

Endovascular repair of complex aortoiliac aneurysms may necessitate distal fixation of the endograft to the external iliac artery and percutaneous embolization of the hypogastric artery for prevention of a retrograde endoleak. However, acute interruption of hypogastric perfusion can result in symptoms of pelvic ischemia. We describe a technique in which a prosthetic graft is used as an external iliac artery conduit to facilitate the passage of the endograft delivery catheter/sheath and after completion of the endovascular portion of the procedure, a surgical bypass is completed with anastomosis of the graft to the hypogastric artery.

Anastomosis, Surgical↗
PubMed2002

Durability of antegrade synthetic aortomesenteric bypass for chronic mesenteric ischemia.

OBJECTIVE: The optimal treatment (endovascular/open repair, conduit, configuration) for chronic mesenteric ischemia (CMI) remains unresolved. This study was designed to review the outcome of patients with CMI treated with antegrade synthetic aortomesenteric bypass. METHODS: The study was designed as a retrospective review in an academic tertiary care medical center. Patients with CMI who underwent antegrade synthetic aortomesenteric bypass were identified from a computerized vascular registry (from January 1987 to January 2001) with antegrade synthetic aortomesenteric bypass as intervention. Outcome measures were functional outcome (symptom relief, weight gain) and both graft patency (duplex ultrasound/angiography) and survival rates as determined with life-table analysis. RESULTS: Forty-seven patients (female, 70%; age, 62 +/- 12 years) underwent aortomesenteric bypass (aortoceliac/aortosuperior mesenteric, n = 45; aortosuperior mesenteric, n = 2) for CMI (abdominal pain, 98%; weight loss, 83%). In-hospital mortality rate was 11% (four multiple organ dysfunction, one bowel infarction), mean length of stay was 32 +/- 30 days, three patients (6%) were discharged to a nursing home, and one (2%) was discharged home on parenteral nutrition (duration 4 months). At a mean follow-up period of 31 +/- 27 months, all patients had relief of abdominal pain and 86% had gained weight (at > or =1 year follow-up: mean ideal body weight 103 +/- 22%; versus before surgery: 87 +/- 17%; P <.001). Fourteen patients (34%) had diarrhea at discharge that persisted more than 6 months in 10. One patient had acute mesenteric ischemia develop from a failed graft (at 20 months), two patients had recurrent CMI develop from failing grafts (at 46 months and 49 months), and one asymptomatic patient was found to have a failing graft with duplex ultrasound scan (at 17 months); all grafts were revised. Primary, primary assisted, and secondary 5-year graft patency rates with life-table analysis were 69% (standard error [SE], 17%), 94% (SE, 7%), and 100%, respectively, and the 5-year survival rate was 74% (SE, 12%). CONCLUSION: Antegrade synthetic aortomesenteric bypass for CMI is associated with good functional outcome and long-term graft patency.

Aorta, Abdominal↗