Brachial artery reconstruction for occlusive disease: A 12-year experience

AbstractObjective: Symptomatic arterial disease of the upper extremity is an uncommon problem. In this study, we evaluate our results with brachial artery reconstruction in patients who present with symptomatic atherosclerotic occlusive disease and compare this cohort's demographics with a similar group with lower extremity ischemia. Methods: From 1986 to 1998, all patients presenting for upper extremity revascularization with chronic ischemia were prospectively entered into a vascular registry. Demographics, indications, outcomes, and patency were recorded. Patients presenting with embolus, pseudoaneurysm, or trauma were excluded. The Fisher exact and Student t tests were used to assess significance. Results: Fifty-one (83%) bypass grafts were performed with autogenous conduit and the remainder with polytetrafluoroethylene. Indications included 18 (30%) patients with exertional arm pain, 35 (57%) with rest pain, and 8 (13%) with tissue loss. Twenty-five (45%) patients were male, 8 (14%) had diabetes, and 30 (54%) were smokers. The mean age was 58 years (range, 33-93). The operative mortality rate was 1.8%, and follow-up ranged from 1 to 140 months. Eight occlusions were identified, with six occurring early. Five of these were in women with a smoking history. Only one of the 26 reconstructions that did not cross a joint occluded, whereas bypass grafts that did cross a joint occluded more frequently. No other major complications were recognized. Conclusion: Arm revascularization for ischemia can be performed with reasonable mortality and morbidity rates. These patients may represent a different subgroup of atherosclerotic disease than those with lower extremity involvement: they are more commonly women and smokers and less likely to be diabetic. (J Vasc Surg 2001;33:802-5.

Infrainguinal arterial reconstruction for claudication: Is it worth the risk? An analysis of 409 procedures

AbstractPurpose: Infrainguinal reconstruction traditionally has been reserved for patients with limb-threatening ischemia. Surgery for debilitating claudication, however, has been discouraged as a result of the perceived fear of bypass graft failure, limb loss, and significant perioperative complications that may be worse than the natural history of the disease. In this study, the results of infrainguinal reconstructions for claudication performed during the past 10 years were evaluated for bypass graft patency, limb loss, and long-term survival rates. Methods: Data were collected and reviewed from the vascular registry, the office charts, and the hospital records for patients who underwent infrainguinal bypass grafting for claudication. Results: From 1987 to 1997, 409 infrainguinal reconstructions were performed for claudication (9% of all infrainguinal reconstructions in our unit). The patient population had the following demographics: 73% men, 28% with diabetes, 54% smokers, and an average age of 64 years (range, 24 to 91 years). Inflow was from the following arteries: iliac artery/graft, 10%; common femoral artery, 52%; superficial femoral artery, 19%; profunda femoris artery, 16%; and popliteal artery, 2%. The outflow vessels were the following arteries: 165 above-knee popliteal arteries (40%), 150 below-knee popliteal arteries (37%), and 94 tibial vessels (23%). The operative mortality rate was 0%, and one limb was lost in the series from distal embolization. The primary patency rates were 62%, 77%, and 86% for above-knee popliteal artery, below-knee popliteal artery, and tibial vessel reconstructions at 4 years, and the secondary patency rates were 64%, 81%, and 90%, respectively. Cumulative patient survival rates were 93% and 80% at 4 and 6 years as compared with 65% and 52%, respectively, for infrainguinal reconstructions performed for limb salvage. Conclusion: Infrainguinal arterial reconstruction for disabling claudication is a safe and durable procedure in selected patients. These data indicate that concern for limb loss, death, and limited life span of the patients with this disease may not be warranted. (J Vasc Surg 1999;29:259-69.

Large Area X-ray Proportional Counter (LAXPC) in Orbit Performance : Calibration, background, analysis software

The Large Area X-ray Proportional Counter (LAXPC) instrument on-board AstroSat has three nominally identical detectors for timing and spectral studies in the energy range of 3--80 keV. The performance of these detectors during the five years after the launch of AstroSat is described. Currently, only one of the detector is working nominally. The variation in pressure, energy resolution, gain and background with time are discussed. The capabilities and limitations of the instrument are described. A brief account of available analysis software is also provided.Comment: Accepted for publication in JA

Carotid-carotid crossover bypass: Is it a durable procedure?

AbstractPurpose: Reconstruction of a diseased common carotid artery may necessitate direct repair via aortic artery-based revascularization. However, carotid-carotid artery crossover grafting is an alternative extra-anatomic option that obviates the need for median sternotomy. We analyzed our results with carotid-carotid artery crossover bypass surgery. Methods: Data were analyzed for all patients undergoing carotid-carotid crossover bypass surgery from 1995 to 2000. Data on patient demographics, indications for surgery, perioperative morbidity and mortality, and graft patency were retrieved from a vascular surgery data base and hospital records. Stroke-free survival and graft patency were determined with life table methods. Results: Over 5 years, 24 carotid-carotid artery crossover bypass procedures were performed to treat both symptomatic (n = 19, 79%) and asymptomatic (n = 5, 17%) disease. Nine procedures (38%) were performed in men, 3 (13%) in patients with diabetes, 12 (50%) in active smokers, and 2 in patients with a history of Takayasu arteritis. Patient mean age was 63 years (range, 38-79 years). Twenty-three patients (96%) received polytetrafluoroethylene conduit grafts, and the remaining patients received vein grafts. Ten (42%) patients underwent concomitant endarterectomy. There were no perioperative deaths. One patient (4%) had asymptomatic early occlusion, one had transient neurologic deficit (4%), one (4%) required additional surgery because of bleeding, and one (4%) had a perioperative cerebrovascular accident (stroke). Three (17%) asymptomatic late occlusions were identified at 11, 57, and 64 months, respectively. Mean follow-up was 30 months (range, 1-70 months). Primary patency was 88%, and secondary patency was 92% at 3 years. Stroke-free survival was 94% at 4 years. Conclusion: Carotid-carotid artery crossover bypass surgery is a safe and durable procedure. Its use precludes the need for median sternotomy and provides acceptable stroke-free survival. (J Vasc Surg 2003;37:582-5.

Strategies to improve spinal cord ischemia in endovascular thoracic aortic repair: Outcomes of a prospective cerebrospinal fluid drainage protocol

PurposeAlthough endovascular repair of thoracic aortic aneurysm has been shown to reduce the morbidity and mortality rates, spinal cord ischemia remains a persistent problem. We evaluated our experience with spinal cord protective measures using a standardized cerebrospinal fluid (CSF) drainage protocol in patients undergoing endovascular thoracic aortic repair.MethodsFrom 2004 to 2006, 121 patients underwent elective (n = 52, 43%) and emergent (n = 69, 57%) endovascular thoracic aortic stent graft placement for thoracic aortic aneurysm (TAA) (n = 94, 78%), symptomatic penetrating ulceration (n = 11, 9%), pseudoaneurysms (n = 5, 4%) and traumatic aortic transactions (n = 11, 9%). In 2005, routine use of a CSF drainage protocol was established to minimize the risks of spinal cord ischemia. The CSF was actively drained to maintain pressures <15 mm Hg and the mean arterial blood pressures were maintained at ≥90 mm Hg. Data was prospectively collected in our vascular registry for elective and emergent endovascular thoracic aortic repair and the patients were divided into 2 groups (+CSF drainage protocol, −CSF drainage protocol). A χ2 statistical analysis was performed and significance was assumed for P < .05.ResultsOf the 121 patients with thoracic stent graft placement, the mean age was 72 years, 62 (51%) were male, and 56 (46%) underwent preoperative placement of a CSF drain, while 65 (54%) did not. Both groups had similar comorbidities of coronary artery disease (24 [43%] vs 27 [41%]), hypertension (44 [79%] vs 50 [77%]), chronic obstructive pulmonary disease (18 [32%] vs 22 [34%]), and chronic renal insufficiency (10 [17%] vs 12 [18%]). None of the patients with CSF drainage developed spinal cord ischemia (SCI), and 5 (8%) of the patients without CSF drainage developed SCI within 24 hours of endovascular repair (P< .05). All patients with clinical symptoms of SCI had CSF drain placement and augmentation of systemic blood pressures to ≥90 mm Hg, and 60% (3 of 5 patients) demonstrated marked clinical improvement.ConclusionPerioperative CSF drainage with augmentation of systemic blood pressures may have a beneficial role in reducing the risk of paraplegia in patients undergoing endovascular thoracic aortic stent graft placement. However, selective CSF drainage may offer the same benefit as mandatory drainage