Andrew T. Gentile

Distal revascularization–interval ligation for limb salvage and maintenance of dialysis access in ischemic steal syndrome☆☆☆★

PURPOSE Traditional options for treating ischemic steal syndrome related to a functioning dialysis access graft or fistula include banding or ligation. Unfortunately, these techniques usually result in inconsistent limb salvage, loss of a functional access, or both. We report our experience with an alternative method of limb revascularization that eliminates steal while maintaining continuous dialysis access. METHODS Patients who had critical limb ischemia and functioning arteriovenous fistulae (AVF) underwent color-flow duplex scanning, digital photoplethysmography, and arteriography. Arterial ligation distal to the AVF origin eliminated the steal physiologic mechanism while arterial bypass grafting from above to below the AVF revascularized the extremity (distal revascularization-interval ligation [DRIL] procedure). RESULTS From March 1994 through December 1996, 21 patients with functioning extremity AVFs presented with critical ischemia and steal syndrome. Eleven patients had chronic ischemia with rest pain, paresthesias, or ulcerations related to nine native fistulae (six brachiocephalic, two basilic vein transpositions, one radiocephalic) and two prosthetic bridge grafts (one upper arm, one lower extremity). Acute ischemia developed in 10 patients related to three native fistulae (two brachiocephalic, one radiocephalic) and seven prosthetic bridge grafts (three forearm, three lower extremity, one upper arm). All 21 patients were treated with the DRIL technique. Three of these patients required treatment for ischemia at the time of AVF construction. Nineteen of 21 bypass procedures were performed with autogenous vein, including nine brachial-brachial, three brachial-radial, two radial-radial, two brachial-ulnar, one popliteal-popliteal, one femoral-popliteal, and one femoral-peroneal. Polytetrafluoroethylene grafts were used for one external iliac-popliteal bypass graft and one axillary-brachial bypass graft. Limb salvage and maintenance of a functional fistula were achieved in 100% and 94%, respectively, at 18 months by life-table analysis. CONCLUSION The DRIL technique reliably restores antegrade flow to the ischemic limb, eliminates the potential pathway for the steal physiologic mechanism, and maintains continuous dialysis access in these difficult patients.

Current trends in the detection and management of carotid body tumors

PURPOSE Because the natural history of carotid body tumors is believed to be unpredictable, immediate surgical removal has been recommended. The present study reviews our experience in the diagnosis and treatment of these uncommon lesions. METHODS The medical records of patients who appeared for treatment with carotid body tumors between 1981 and 1997 were reviewed. Patients demographics, mode of presentation, imaging and treatment modalities, Shamblin classification, and neurologic complications (stroke, cranial nerve injuries) were analyzed. RESULTS Over the past 16 years, 31 patients with 32 carotid body tumors have been evaluated, with an average follow-up of 3.2 years. The patients were arbitrarily classified into two groups on the basis of the mode of detection. Seventy percent (23 of 32) of the tumors discovered on clinical or self-examination were classified as Group 1; 28% (9 of 32) of the tumors detected during duplex scanning for carotid artery disease (8) or MRI (1) were classified as Group 2. The mean size of chemodectomas found on palpation (4.3 +/- 1.7 cm) was larger than that of those detected by duplex ultrasound (2.7 +/- 1.0 cm; p < 0.05, by paired t test). Preoperative embolization was successfully performed in 5 of 6 instances of large tumors; the remaining patient suffered a procedure-related stroke. Thirty-one carotid body tumors were resected. In one case, the tumor was felt by the primary surgeon to be too small (0.9 x 0.7 cm on duplex scan) to warrant immediate excision; this patient is being followed by periodic duplex scanning. Five neurologic complications were noted in Group 1, one after preoperative embolization and four after surgery. One cranial nerve injury occurred in Group 2. One patient had a large recurrent chemodectoma with clinical evidence of metastatic disease. CONCLUSION The increasing use of sophisticated imaging modalities may allow earlier discovery of carotid body tumors before they can be clinically detected. Resection of carotid body tumors of all sizes in appropriate surgical candidates remains the standard of care. Unfortunately, resection of even small tumors is associated with a low but constant incidence of neurologic complications.

Results of bypass to the popliteal and tibial arteries with alternative sources of autogenous vein

PURPOSE The goal of an all-autogenous policy for infrainguinal arterial bypass requires that many bypasses be performed with alternative autogenous veins (AAV) because an adequate length of ipsilateral or contralateral greater saphenous vein (GSV) is not available. The durability and efficacy of infrainguinal vein bypasses constructed of venous conduits other than a single segment of greater saphenous vein (SSGSV) is, however, questioned. METHODS AAV and GSV bypasses were reviewed from 1980 through 1994. Patients who required bypass to the popliteal or a tibial artery were compared for vascular surgical history and vascular disease risk factors and life-table survival. AAV and SSGSV procedures were compared for indications for surgery, morbidity and mortality rates, limb salvage rates in patients who underwent surgery for limb-salvage indications, subsequent need for revision, and life-table-assisted primary patency. RESULTS Nine hundred nineteen autogenous vein bypasses were performed to the popliteal or a tibial artery--187 (20%) with AAVs, including whole or partial arm vein conduits in 144 grafts (77%). One hundred fourteen AAVs (61%) required vein splicing. The mortality rate was 2% for SSGSV bypasses and 1% for AAV bypasses. The morbidity rate was higher for GSV surgery as a result of increased wound complications (11% vs 5%; p=0.02). Sixty-seven percent of patients with AAV bypass extremities had undergone previous ipsilateral arterial surgery, compared with 20% of patients with SSGSV bypasses (p0.0005). AAV bypasses were more likely to be to a tibial artery (71% vs 45%; p<0.0001). Twelve percent of SSGSV and 15% of AAV popliteal bypasses required revision (p=NS). The 5-year assisted primary patencies were 82%, 77%, and 63%, with limb salvage rates of 91%, 86%, and 74% for ipsilateral SSGSV, contralateral SSGSV, and AAV femoropopliteal bypasses, respectively. Twelve percent of SSGSV and 30% of AAV tibial bypasses required revision (p=0.0001). The 5-year assisted primary patencies were 74%, 82%, and 72%, with limb salvage rates of 84%, 92% and 78% for ipsilateral SSGSV, contralateral SSGSV, and AAV femorotibial bypasses, respectively. CONCLUSION AAV bypasses can provide overall results comparable with SSGSV bypasses.

Treatment of patients with venous thromboembolism and malignant disease: Should vena cava filter placement be routine?

PURPOSE It has been proposed that inferior vena cava filter placement should be the initial treatment of deep venous thrombosis (DVT) or pulmonary embolus (PE) in patients with coexisting malignant disease. We have chosen instead to selectively place filters only in patients with either a contraindication to anticoagulation therapy or a subsequent complication from anticoagulation therapy. The treatment efficacy and mortality rates in patients with concomitant malignant disease and venous thromboembolism using this approach was determined. METHODS We retrospectively reviewed all patients at our institution with malignant disease in whom venous thromboembolism developed between August 1991 through August 1996 and identified 166 patients with PE (n = 8), DVT (n = 147), and DVT/PE (n = 11). Of these patients, 138 (83.1%) were initially treated with anticoagulation therapy, and 28 (16.9%) had primary filter placement because of contraindications to anticoagulation therapy (10 for intracranial tumors, 11 for recent or upcoming operations, 6 for recent hemorrhage, and 1 for a malignant bloody pericardial effusion). RESULTS Thirty-two (23%) of the 138 patients who initially underwent anticoagulation therapy subsequently required a filter for the following reasons: bleeding (n = 15, 10.9%); recurrent thromboembolism (n = 6, 4.3%); heparin-induced thrombocytopenia (n = 1, 0.7%); and perceived high risk for bleeding with continued anticoagulation therapy (n = 11, 8%). Both bleeding and recurrent thromboembolism developed in 1 patient. Sixty patients (36%) received filters. No major technical complications occurred from filter placement. Major recurrent thromboembolic complications developed in 10 patients: DVT (n = 6, 10%), PE (n = 2, 3.3%), inferior vena cava thrombosis and phlegmasia cerulea dolens (n = 1, 1.7%), superior vena cava thrombosis (n = 1, 1.7%). Venous gangrene developed in 1 patient with DVT. The 1-year actuarial survival rates for patients treated with filter and anticoagulation therapy were 35% and 38%, respectively (P = NS). CONCLUSION In summary, our experience suggests that 64% of patients with malignant disease and venous thromboembolism are effectively treated with anticoagulation alone; 17% require primary filter placement for standard indications, and an additional 19% require subsequent filter placement because of complications (primarily bleeding) or failure of anticoagulation therapy. Although technical complications of filter placement are low, serious life-threatening or limb-threatening thromboembolic complications developed in 17% of patients. Survival was poor in all patients, regardless of treatment. These data support a conservative approach of routine anticoagulation therapy with selective filter placement.

Usefulness of fasting and postprandial duplex ultrasound examinations for predicting high-grade superior mesenteric artery stenosis

PURPOSE A fasting duplex ultrasound examination of the superior mesenteric artery (SMA) accurately detects high-grade (> 70%) stenosis. It has been postulated that postprandial mesenteric duplex scanning may further stratify stenosis and improve the ability of a fasting examination to detect a high-grade stenosis. We performed fasting and postprandial duplex scanning of 25 healthy controls and 80 patients with vascular disease undergoing aortography to determine whether postprandial mesenteric duplex scanning provides information beyond a fasting study alone. METHODS Patients with vascular disease were divided into three groups based on lateral aortography results: group 1, 0% to < 30% SMA stenosis (n = 61); group 2, 30% to < 70% stenosis (n = 10); and group 3, 70% to 99% stenosis (n = 9). Fasting mesenteric duplex scanning was defined as positive for 70% to 99% stenosis if the peak systolic velocity (PSV) was > or = 275 cm/s. The ability of either fasting or postprandial mesenteric duplex scanning, and their combination, to predict high-grade (70% to 99%) SMA stenosis was determined using angiographic control. RESULTS Mean fasting SMA PSV did not differ among controls and groups 1 and 2. Postprandial PSV increased significantly in all groups, but was not different among controls and groups 1 and 2. Mean fasting PSV was significantly higher, and the postprandial increase in PSV significantly lower, in group 3 compared with controls and with groups 1 and 2. Fasting mesenteric duplex scanning predicted 70% to 99% SMA stenosis, with 89% sensitivity, 97% specificity, 80% positive predictive value, 99% negative predictive value, and 96% accuracy. Corresponding values for postprandial scanning were 67%, 94%, 60%, 96%, 91%, and for the combination of normal fasting and postprandial scanning 67%, 100%, 100%, 96%, 96%, respectively. CONCLUSION Postprandial increases in SMA PSVs are blunted in patients with high-grade stenosis, but feeding velocities do not stratify between lesser degrees of stenosis. Both fasting and postprandial PSVs identify high-grade (> 70%) stenosis. Their combination marginally improves fasting duplex scan specificity and positive predictive value. Postprandial scanning is not necessary for the diagnosis of high-grade stenosis if a fasting study identifies a PSV > or = 275 cm/s. The combination of normal fasting and postprandial mesenteric duplex ultrasound scanning may effectively rule out high-grade SMA stenosis.

Identification of Predictors for Lower Extremity Vein Graft Stenosis

BACKGROUND The cause of intrinsic vein graft stenosis, which develops in at least 20% of infrainguinal autogenous bypass grafts during the intermediate follow-up interval, is unknown. We performed standard duplex surveillance of all lower extremity bypass grafts and evaluated the potential of comorbid patient risk factors that might predict development of vein graft flow disturbance or high-grade graft stenosis. METHODS Patients with at least 6 months of postoperative duplex surveillance were identified through our vascular registry. The association of clinical and hemodynamic profiles of graft performance were compared with specific patient risk factors, including demographics, cigarette smoking, antihypertensive medical therapy, type and quality of conduit, degree of ischemia, bypass run-off, and presence of infection, using stepwise logistic regression analysis. RESULTS Ninety-three patients (55 male, 38 female; mean age 69) underwent 100 infrainguinal bypasses. Twenty-six high-grade graft stenoses (>70%) were identified in 26 patients during follow-up (mean 21 months) by graft-flow peak systolic velocity (PSV) >300 cm/sec on more than one duplex examination, and were electively revised. Graft flow disturbances (180 cm/sec >PSV <300 cm/sec) were identified in an additional 13 grafts (6 regressed, 7 observed). The need for graft revision was associated with an early graft flow disturbance (P = 0.02), or drop in ankle-brachial index >0.15 (P = 0.03), and the use of an alternative conduit in 13 of 100 grafts (P = 0.04). Only smoking was associated with the development of a duplex detected graft flow disturbance during follow up (P = 0.03). CONCLUSION Grafts with early flow disturbances warrant close duplex surveillance to identify graft-threatening stenosis. Risk factors that may predict future lower extremity bypass graft stenosis are smoking and the use of alternative bypass conduits.

Comparison of carotid endarterectomy using primary closure, patch closure, and eversion techniques

BACKGROUND This study was undertaken to evaluate the role of eversion endarterectomy in the management of extracranial carotid occlusive disease. METHODS A retrospective review was performed of all patients undergoing carotid endarterectomy between July 1994 and July 1998. After reviewing the records, patients were assigned to one of three groups: eversion (ECEA); open with primary closure (CEA); or open with patch closure (CEAP). Statistical comparisons were made. RESULTS The 190 index cases comprised 33 ECEA (17%), 15 CEA (8%), and 142 CEAP (75%). Both ECEA and CEA were more likely to be done on males versus females compared with CEAP (P = 0.01). For the entire 190 cases, stroke occurred in 1 patient (0.5%); and myocardial infarction in 2 patients (1%), resulting in death in both. Two patients (1.4%) in the CEAP group have undergone redo surgery at 8 and 24 months. CONCLUSIONS This study demonstrates that eversion endarterectomy achieves early results similar to open endarterectomy with and without patch closure.

The Utility of Polyglycolic Acid Mesh for Abdominal Access in Patients With Necrotizing Pancreatitis

BACKGROUND Necrotizing pancreatitis is a poorly understood process that has been treated by a variety of surgical approaches. Despite advances in operative interventions and critical care, this disease often requires prolonged resource allocation and continues to cause substantial morbidity, with mortality rates ranging from 11% to 40%. We report on our recent series of patients with necrotizing pancreatitis and our experience with the use of an absorbable mesh in a subset of these patients to facilitate their surgical care. STUDY DESIGN From 1985 to 1994, 40 patients with culture-proved necrotizing pancreatitis underwent operative debridement and drainage. Surgical outcomes were compared among patients who underwent a single debridement and drainage, those requiring multiple procedures, and those having placement of polyglycolic acid mesh. RESULTS The overall hospital mortality rate was 30%. The mean length of hospital stay was 35 days. The rate of infected pancreatic necrosis was 60%, with a mortality rate of 45% in patients having infected pancreatic tissue at surgery. Patients without infected pancreatic tissue at surgery had a mortality rate of 6% (p = 0.03). Eleven patients requiring multiple operations had placement of absorbable polyglycolic acid mesh. Clinic followup was possible in five of six survivors who underwent mesh closure. Abdominal-wall hernias developed in two patients and were repaired electively, and three patients had spontaneous closure by granulation without abdominal-wall hernias. The average number of operations for debridement and drainage was 2.5 (range, 1-15). Patients with limited pancreatic necrosis required a single operative debridement and drainage, and this was associated with improved outcomes. CONCLUSIONS Necrotizing pancreatitis remains an important challenge in surgical care. It requires prolonged hospitalization, costly resources, and causes substantial morbidity and mortality. Our patients with infected pancreatic necrosis or clinical deterioration underwent open staged necrosectomy and debridement. Those patients requiring repeat laparotomy often had placement of polyglycolic acid mesh. This provided open drainage of the abdominal cavity and simplified further care by allowing easy abdominal access for repeat drainage procedures, often performed in the intensive care unit. These patients had a high rate of fistula formation, which may be decreased by changes in wound care. Polyglycolic acid mesh is a useful adjunct in the surgical care of selected patients with necrotizing pancreatitis.

Salvage of femoropedal bypass graft complicated by interval gangrene and vein graft blowout using a flow-through radial forearm fasciocutaneous free flap

We report the case of a 71-year-old man who had interval gangrene of his calf with subsequent vein graft blowout 3 months after undergoing a femoral-to-dorsalis pedis saphenous vein bypass grafting procedure. To provide wound coverage, restore vascular continuity, and preserve functional ambulation, a flow-through radial forearm fasciocutaneous free flap was interposed between cut ends of the bypass graft. Venous drainage of the flap was from the cephalic vein to the popliteal vein. At 1 month after the operation, the patient had complete wound healing and began to ambulate. At 11 months an asymptomatic high-grade stenosis in the distal radial artery segment of the reconstruction was successfully treated with percutaneous angioplasty. After 22 months of follow-up there have been no further complications, and the patient continues to have full, functional ambulation. The radial forearm flow-through free flap allows single-stage restoration of bypass graft continuity and coverage of extensive, complex tissue defects. This technique represents a novel approach to this difficult problem and provides a viable alternative to major limb amputation.

Common Bile Duct Obstruction Related to Intestinal Polyposis in a Child With Peutz- Jeghers Syndrome

Peutz-Jeghers syndrome is characterized by hamartomatous polyposis of the small and large bowel and mucocutaneous pigmentation. The authors describe a 9-year-old girl with small bowel obstruction related to duodenal intussusception caused by polyposis in the fourth portion of the duodenum. Operative reduction of the intussusception and excision of the polyps were performed, at which time the pancreas appeared to have mild pancreatitis. A liver biopsy specimen showed mild portal fibrosis and ductal proliferation. The patient did well postoperatively, but later presented with symptoms consistent with biliary obstruction. Percutaneous transhepatic cholangiography showed pancreatic and biliary duct dilatation as well as obstruction of the common bile duct, which extended into the left upper quadrant. Exploration showed ampullary obstruction several centimeters proximal to the line of resection. Sphincteroplasty was performed. The postoperative course was uncomplicated. The authors conclude that Peutz-Jeghers syndrome with polyps in the duodenum can markedly distort duodenal and ductal anatomy and can lead to ampullary obstruction.