Joseph L. Mills

The characteristics and anatomic distribution of lesions that cause reversed vein graft failure: A five-year prospective study ☆ ☆☆

PURPOSEnThe cause of vein graft failure in the intermediate postoperative period (3 to 18 months) has not been well defined. To delineate the incidence, characteristics, and anatomic distribution of lesions that cause graft failure in this critical interval, 227 consecutive infrainguinal reversed vein grafts (IRVGs) constructed at a single institution from July 1986 to December 1991 were prospectively entered into a duplex scan surveillance protocol.nnnMETHODSnDuplex surveillance with arteriographic confirmation identified 29 patent, hemodynamically failing IRVGs during a mean follow-up of 22 months (range 1 to 64 months). An additional 18 grafts thrombosed before detection of any underlying abnormality; thrombolytic therapy and repeat operation uncovered the cause of occlusion in 12 of these grafts. The cause of graft failure (failing as well as failed) was therefore clear in 41 (87.2%) of 47 instances.nnnRESULTSnThe causes of failure were intrinsic graft stenosis (n = 28; 59.6%), inflow failure (n = 6; 12.8%), outflow failure (n = 4; 8.5%), muscle entrapment (n = 2; 4.3%), and hypercoagulable state (n = 2; 4.3%). The most common intrinsic graft lesion was focal intimal hyperplasia (18 lesions in 16 grafts) in the juxtaanastomotic position, occurring solely in the vein graft itself. It occurred with equal frequency immediately distal to the proximal anastomosis or proximal to the distal anastomosis. Only rarely (n = 5) did this involve the juxtaanastomotic artery. Focal midgraft valvular stenoses (n = 6) and diffuse myointimal hyperplasia (n = 4) were also detected. The peak incidence of graft failure was 4 to 12 months after operation (70% within 12 months, 80% within 18 months).nnnCONCLUSIONSnWe conclude that duplex surveillance of IRVGs is warranted by the 21% incidence of potentially remediable graft failure. A significant portion of these failures occur during the intermediate postoperative period (3 to 18 months), usually as a result of focal intrinsic vein graft lesions. With reversed vein conduits, these lesions arise predominantly in the vein graft itself, in the juxtaanastomotic position.

Minimizing mortality and morbidity from iatrogenic arterial injuries: The need for early recognition and prompt repair

Seventy-one cases of iatrogenic arterial injury requiring repair at our institution from 1972 through 1984 were retrospectively analyzed. Cardiac catheterization accounted for most of the injuries (62%). Ten injuries (14%) resulted from angiography or percutaneous transluminal angioplasty; four injuries (5.6%) occurred after invasive monitoring devices were inserted. Six injuries (8.45%) stemmed from complications of intra-aortic balloon pump insertion, whereas the remainder occurred during various surgical procedures. Most injuries were in the femoral (42.3%) and brachial (38.1%) locations. Thrombectomy (23.9%) and resection with end-to-end anastomosis (35.2%) were the repairs most commonly performed. Morbidity and mortality were low; only one case resulted in limb loss, and neither of the two deaths resulted from the vascular repair itself. On the basis of our experience, we can make certain recommendations with regard to specific injuries. First, the conservative approach to brachial artery thrombosis occurring after catheterization is early exploration and repair. Second, although most injuries can be managed simply with thrombectomy and primary repair, iliofemoral injuries are more likely to require complex reconstructive techniques. Third, large-bore catheter injuries to the carotid artery require immediate exploration and repair to prevent thrombosis, pseudoaneurysm, and cerebral embolism. Fourth, symptoms of nerve compression after transaxillary arteriography require prompt exploration. Our results indicate that, depending on the site of injury, individualized techniques of varying complexity are required for repair. In general, serious sequelae can be minimized by early recognition, prompt operation, and adherence to sound vascular surgical principles.

Intraoperative duplex scanning of arterial reconstructions: Fate of repaired and unrepaired defects * **

PURPOSEnBecause unrecognized lesions can cause an arterial reconstruction to fail, duplex ultrasonography was evaluated as an intraoperative aid to assess technical adequacy and provide criteria for which lesions should be repaired immediately versus safely followed.nnnMETHODSnSince 1990 intraoperative color duplex scanning(7 to 10 MHz linear array probe, pulsed-wave Doppler test spectrum analysis) was used to assess the frequency and severity of residual lesions in 368 patients after carotid endarterectomy (n = 210), infrainguinal vein bypass (n=135) or visceral/renal reconstruction (n = 23). Duplex scan results were categorized as normal or abnormal, with immediate repair of lesions demonstrating both lumen reduction and severe focal flow abnormalities (peak systolic velocity [Vp] > 150 to 180 cm/sec;velocity ratio [Vr] > 2.4). Arteriography was also performed in 81% of lower limb bypass procedures.nnnRESULTSnDuplex scanning identified technical (residual plaque, stricture) or intrinsic defects (platelet thrombus, distal thrombosis) requiring revision in 37 (10%) of the reconstructions. Infrainguinal bypass had the highest incidence of corrected defects (14%) and adverse events (3%). No adverse events occurred in patients with normal duplex scan results or after carotid endarterectomy. Overall, 76% of identified defects were corrected (carotid, 17 of 24; infrainguinal bypass, 19 of 24; visceral bypass, 1 of 1). Unrepaired flow defects (Vp = 150 to 190 cm/sec; Vr = 1.8 to 2.5) led to one graft occlusion and three early revisions. Postoperative duplex scanning demonstrated residual stenosis in seven of 12 patients with unrepaired defects, two of 36 patients with repaired defects, and five of 312 patients with normal scan results (p < 0.001).nnnCONCLUSIONnBased on the types of lesions corrected and the low (< 0.5%) complication rate after a normal or modified arterial reconstruction, duplex scanning was found to be a valuable intraoperative aid. Unrepaired defects require close surveillance for progression.

Comprehensive Vascular and Endovascular Surgery

Comprehensive vascular and endovascular surgery , Comprehensive vascular and endovascular surgery , کتابخانه مرکزی دانشگاه علوم پزشکی تهران

Utility of routine carotid duplex screening in patients who have claudication

PURPOSEnThe recently published Asymptomatic Carotid Atherosclerosis Study (ACAS) demonstrated the benefit of performing carotid endarterectomy in selected asymptomatic patients who have > 60% carotid stenoses. It therefore becomes clinically important to identify the subgroups of patients who have a sufficiently high incidence of high-grade carotid stenosis to warrant routine carotid duplex screening.nnnMETHODSnTo determine the incidence of asymptomatic carotid disease in patients who had a chief complaint of claudication, we evaluated 188 patients who had claudication and no history of cerebrovascular symptoms. After a complete history was taken and a physical examination performed, patients underwent standard lower-extremity noninvasive vascular laboratory studies and carotid duplex scanning. Carotid duplex findings were interpreted by the Strandness criteria. Associated atherosclerotic risk factors were assessed (patient age, male sex, diabetes, hypertension, smoking history, lipid levels, history of coronary artery disease, coronary or vascular surgery, and family history of cerebrovascular disease). Presence of a carotid bruit was also noted. Univariate analysis, logistic regression, and odds ratios were performed to identify subgroups of patients that had an increased incidence of significant carotid disease.nnnRESULTSnOf the 188 patients with claudication who were screened, 8% had an internal carotid artery stenosis of 16% to 49%, 21.8% had a stenosis that exceeded 50%, and 2.7% had an occluded internal carotid artery. The presence of a carotid bruit on physical examination was predictive of a > or = 50% internal carotid artery stenosis (p = 0.027). The ankle-brachial index was highly predictive of the presence of carotid stenoses in an inverse relationship (p = 0.001). Patient age approached significance (p = 0.143). Patients older than 65 years of age who had claudication, an ankle-brachial index less than 0.7, and a carotid bruit had a 45% incidence of significant carotid disease. The atherosclerotic risk factors of male sex, diabetes, hypertension, hyperlipidemia, smoking history, coronary history, previous coronary or vascular surgical history, and family history were not predictive of the presence of a > 50% carotid stenosis.nnnCONCLUSIONSnIn patients who seek medical attention with the chief complaint of claudication and who have no cerebrovascular symptoms, there is a 24.5% incidence of a > 50% internal carotid artery stenosis or occlusion on duplex examination. Select subsets of these patients have upwards of a 45% incidence of significant asymptomatic carotid disease. All patients who seek medical attention with claudication should therefore undergo routine carotid duplex screening to detect asymptomatic high-grade stenosis.

The effect of unilateral internal carotid arterial occlusion upon contralateral duplex study: Criteria for accurate interpretation

To determine the influence of unilateral internal carotid arterial occlusion (ICO) on Doppler frequency spectral analysis (DFSA) of the patent contralateral carotid artery, a retrospective review of 154 patients between July 1987 and December 1991 with angiographically confirmed ICO was performed, correlating duplex and arteriographic findings in a blinded fashion. Biplane arteriograms and bilateral carotid artery duplex studies that used a 5.0 MHz Doppler probe with a 1.5 mm3 sample volume at a 60 degree angle of insonation were performed on all patients. Each carotid artery was categorized by the severity of stenosis as quantified by arteriography: 1% to 15% (n = 41); 16% to 49% (n = 48), 50% to 79% (n = 21), 80% to 99% (n = 34), and bilateral occlusion (n = 10). DFSA peak systolic frequencies were commonly exaggerated in the presence of contralateral ICO and use of standard criteria for DFSA interpretation overestimated bifurcation stenoses in 43 of 89 lesions (48.3%) when determining nonhemodynamically significant lesions (less than 50% diameter reduction) with a sensitivity of only 57.3% and specificity of 96.9%. Conversely, prediction of hemodynamically significant lesions (greater than 50% diameter reduction) with standard criteria had 96.9% sensitivity but only 57.3% specificity. Modification of these criteria to account for the velocity increase or jet effect in the ipsilateral carotid artery system increased the sensitivity and specificity to 97.8% in predicting nonhemodynamically and hemodynamically significant stenoses respectively. A Doppler frequency spectrum with a peak systolic frequency (PSF) greater than 4.0 kHz and end-diastolic frequency (EDF) less than 5 kHz with an open window distinguished lesions with less than 50% diameter reduction.(ABSTRACT TRUNCATED AT 250 WORDS)

A reevaluation of intraarterial thrombolytic therapy for acute lower extremity ischemia

PURPOSEnThis study was performed to clarify the role of intraarterial thrombolytic therapy (IATT) in the management of acute lower extremity ischemia.nnnMETHODSnA retrospective review of 77 patients undergoing 84 courses of high-dose regional urokinase IATT from July 1981 to June 1991 was performed. The group included patients with acute thrombosis of lower extremity bypass grafts (n = 48) or native arteries (n = 36), presenting with ischemic but viable limbs, minimal or no motor dysfunction, and an absence of muscle rigor or compartment syndrome. The data were then examined individually by site of thrombosis to evaluate patient selection for IATT.nnnRESULTSnComplete lysis, complications (either distal thromboembolism or bleeding), and early limb loss occurred in 59.5%, 11%, and 6% of infusions, respectively. IATT precluded the need for operative intervention in 49% of acutely ischemic limbs. When surgery was required, successful IATT precisely localized responsible lesions and reduced the magnitude of operation. A subset of 13 patients were identified in whom either no intrinsic abnormality or poor runoff were evident after lysis and were treated with anticoagulation alone.nnnCONCLUSIONSnThese data show IATT to be especially suitable for thrombosis of native iliac or femoropopliteal arteries and infrainguinal vein grafts. IATT serves primarily as an adjunct in management of acute lower extremity ischemia. After successful IATT, subsequent therapy can be tailored to the anatomic cause of thrombosis.

The utility and durability of vein bypass grafts originating from the popliteal artery for limb salvage

BACKGROUNDnShort vein grafts originating from sites distal to the common femoral artery have been reported to be useful in selected patients with tibial artery disease. From 1987 to 1993, we performed 504 consecutive infrainguinal vein bypass grafts, of which 56 (11%) originated from the popliteal artery, 25 above and 31 below the knee.nnnPATIENTS AND METHODSnThe patients were 16 women and 37 men, with a mean age of 62.4 years. Eighty-seven percent were diabetic, 57% had clinically obvious coronary artery disease, and 28% had end-stage renal disease (ESRD). The indication for surgery was ulceration or gangrene in 93% of cases. We preferentially used reversed greater saphenous vein harvested from the thigh to optimize conduit quality and avoid lower leg wound complications. The outflow artery sites were: dorsal pedal (17), posterior tibial (14), peroneal (10), anterior tibial (8), lateral or medial plantar (5), and sequential tibial (2). All patients were followed postoperatively with serial duplex surveillance. The mean follow-up was 12.5 months (range 1 to 66).nnnRESULTSnIn-hospital mortality was 5.4%. Mortality at 24 months was 19% overall and 38% in patients with ESRD. Limb salvage was 77% at 3 years, 92% in patients with normal renal function versus 59% in those with ESRD (P < 0.003). Primary graft patency by life-table analysis was 94% at 1 month and 84% at 3 years. Five patients with patent grafts required amputation, 4 early and 1 late. Eight months after surgery, 1 patient (1.8%) developed superficial femoral artery stenosis which was diagnosed by duplex surveillance and successfully treated by percutaneous transluminal balloon angioplasty.nnnCONCLUSIONSnVein bypass grafts originating from the popliteal artery are effective and durable. Proximal disease progression rarely poses a significant threat to long-term graft patency. Patients with ESRD, blind tibial outflow tracts, and extensive forefoot lesions appear to be at increased risk of limb loss even with continued graft patency.

The role of the deep femoral artery as an inflow site for infrainguinal revascularization

PURPOSEnAlthough the deep femoral artery (DFA) is well acknowledged as an outflow vessel for inflow reconstruction, data are lacking concerning the suitability of the DFA as an inflow site for distal bypass.nnnMETHODSnFrom 1986 to 1992 we performed 268 consecutive infrainguinal reversed vein bypasses, of which 56 (21%) originated from the middle or distal DFA. The indications for DFA-origin grafts included inadequate vein length, need for concomitant extended profundaplasty, and avoidance of groin scarring from previous reconstruction or infection. The surgical approach to the DFA (standard, posteromedial, or lateral) was tailored to the patient. All grafts were monitored with serial duplex scanning surveillance.nnnRESULTSnPrimary and secondary patency rates of DFA origin grafts were 78% and 96% at 3 years. These patency rates were no different from those grafts originating from the common femoral artery (66%; 89%), the superficial femoral artery (69%; 87%), or the popliteal artery (66%; 87%). Hemodynamic failure was detected in seven DFA-origin grafts, but only one resulted from disease in the common femoral artery or DFA proximal to the origin of the vein graft.nnnCONCLUSIONSnDirect lateral and posteromedial approaches to the DFA were used extensively in repeat operative situations, avoiding dissection in a scarred groin and shortening the length of vein required to perform an autogenous bypass. We conclude that in appropriately selected patients, the DFA origin technique increases the versatility of lower extremity vein bypass grafting without sacrificing durability.

Results of infrainguinal revascularization with reversed vein conduits: a modern control series

To determine the outcome of infrainguinal reversed vein bypasses in the modern era, we reviewed the results of 120 consecutive reversed vein grafts performed from March, 1986 to March, 1990. Forty-nine bypasses were to tibial, peroneal, or pedal arteries, 46 grafts to the below-knee popliteal artery, and 25 grafts to the above-knee popliteal artery. Limb salvage was the indication for revascularization in 70% of patients. All grafts were followed with serial, duplex scan, peak-systolic graft flow velocity measurements every three months for one year and every six months thereafter. The primary life table patency rate at 36 months was 67.6% for the entire series; the secondary patency rate was 92.5%. The secondary patency rate reflects the impact of graft revisions resulting from the detection of failing grafts by duplex scanning. Patency rates of reversed vein grafts to the tibial arteries at 36 months (73.8% primary and 89.8% secondary) were equivalent to those performed to the popliteal artery. Our current patency rates with reversed vein grafts are comparable or superior to those reported for in-situ vein conduits and suggest that operative technique and meticulous follow-up are more important with respect to long-term graft durability than whether the vein is used in the in-situ or reversed configuration.