Faculty Bibliography

Diagnostic arteriography and balloon angioplasty of failing or nonmaturing arterio-venous (AV) access is based upon using nephrotoxic contrast. Patients not yet on dialysis with borderline renal function with nonmaturing AV accesses or ones with an allergy to contrast media present a therapeutic challenge. We have used duplex scanning as an alternative imaging modality to guide endovascular therapy in 10 cases (9 autologous and 1 prosthetic). Six target AV accesses (60%) were used for dialysis. Number of stenoses ranged from 1 to 5 per AV access. Short access sheath insertion, wire and balloon passage, and inflation were guided by duplex only. Balloon size (5-8 mm in diameter) was chosen based on duplex measurements. Cutting balloons (4 x 20 mm and 5 x 20 mm) were used for dilatation of recoiling lesions in 4 cases. One patient had a self-expanding stent placed under duplex-guidance for recoiling lesion in the junction of the brachial and axillary veins. Angioplasty of failing AV access can be performed under duplex guidance alone. Duplex guidance offers very important advantages of hemodynamic evaluation for recoiling lesions and need for stenting. Avoidance of contrast use for repair of nonfunctioning AV access can be a useful option in patients with renal failure not yet on dialysis or in cases of allergy.

OBJECTIVE: We have investigated whether popliteal artery volume flow (PAVF) measured immediately after balloon angioplasties of the superficial femoral artery-popliteal segments (SFA/POP) was predictive of early (30 days) and mid-term (6 months) arterial thrombosis. METHODS: During the last 24 months, 203 patients (56% men) with a mean age of 73 +/- 9 years had 268 duplex-guided balloon angioplasties of the SFA/POP. Critical ischemia was the indication in 36%. Group I included 176 (66%) with stenoses, and group II had 92 (34%) with occlusions. All patients had completion duplex examinations that included three measurements of PAVF of below-the-knee popliteal artery. RESULTS: Early (30 days) thrombosis of the treated femoropopliteal arterial segment developed in 10 patients (3.7%), three in group I (1.7%) and seven in group II (7.6%; P < .04). All 10 cases of early thrombosis were in patients with TransAtlantic Inter-Society Consensus (TASC) class C (6/185, 3.2%) and D (4/26, 15%) lesions. Moreover, the 19% incidence (n = 4) of early thrombosis in patients with PAVF <100 mL/min (mean, 73 +/- 24 mL/min; range, 20 to 99 mL/min) was higher compared with the 2.4% rate for patients with higher flows (mean, 176 +/- 60 mL/min; range, 100 to 450 mL/min; P < .01). At 6 months of follow-up, femoropopliteal occlusions had developed in nine more patients, and it became apparent that low PAVF measurements were still predictive of thrombosis (29%) when compared with higher PAVF cases (6%; P < .002). Log-rank comparison of survival curves for cumulative primary stenosis-free patency in group I and group II demonstrated a statistically significant difference (P < .02). PAVF <100 mL/min and TASC classification were significant predictors of early (30 days) and mid-term (6 months) arterial thrombosis after femoropopliteal angioplasties. PAVF was the most powerful predictor of arterial thrombosis. The respective 6-month and 12-month limb salvage rates were 98% and 94% for patients with claudication and 88% and 85% for those with limb-threatening ischemia (P < .0001). CONCLUSIONS: Our results demonstrate that low PAVF is the most powerful predictor of early (30 days) and mid-term (6 months) arterial thrombosis after femoropopliteal interventions. In the presence of a low postprocedure PAVF (<100 mL/min), one may consider not reversing the heparin or using intermittent calf compression, or both, to augment the arterial flow.

OBJECTIVE: The standard technique of balloon angioplasty with or without subintimal dissection of infrainguinal arteries requires contrast arteriography and fluoroscopy. We attempted to perform this procedure with duplex guidance to avoid the use of nephrotoxic contrast material and eliminate or minimize radiation exposure. METHODS: From September 2003 to June 2005, 196 patients (57% male) with a mean age of 73 +/- 10 years (range, 42-97 years) had a total of 253 attempted balloon angioplasties of the superficial femoral and/or popliteal artery under duplex guidance in 218 limbs. Critical ischemia was the indication in 38% of cases, and disabling claudication was the indication in 62%. Hypertension, diabetes, chronic renal insufficiency, smoking, and coronary artery disease were present in 78%, 51%, 41%, 39%, and 37% of patients, respectively. The TransAtlantic Inter-Society Consensus (TASC) classification was used for morphologic description of femoral-popliteal lesions. The common femoral artery was cannulated under direct duplex visualization. Still under duplex guidance, a guidewire was directed into the proximal superficial femoral artery, across the diseased segment(s), and parked at the tibioperoneal trunk. The diseased segment(s) were then balloon-dilated. Balloon diameter and length were chosen according to arterial measurements obtained by duplex scan. Hemodynamically significant defects causing diameter reductions greater than 30% and peak systolic velocity ratios greater than 2 were stented with a variety of self-expandable stents under duplex guidance. Completion duplex examinations and ankle-brachial indices were obtained routinely before hospital discharge. RESULTS: There were 11 (4%) TASC class A lesions, 31 (12%) TASC class B lesions, 177 (70%) TASC class C lesions, and 34 (14%) TASC class D lesions in this series. The overall technical success was 93% (236/253 cases). Eight of the 17 failed subintimal dissections belonged to TASC class C and the remaining 9 to TASC class D. End-stage renal disease was the only significant predictor of subintimal dissection failure in patients with femoral-popliteal occlusions (5/17 cases; P < .04). Intraluminal stents were placed in 153 (65%) of 236 successful cases. Overall pre-procedure and post-procedure ankle-brachial indices changed from a mean of 0.69 +/- 0.16 (range, 0.2-1.1) to 0.95 +/- 0.14 (range, 0.55-1.3), respectively (P < .0001). The mean duration of follow-up was 10 +/- 7 months (range, 1-29 months). The overall 30-day survival rate was 100%. Overall limb salvage rates were 94% and 90% at 6 and 12 months, respectively. Six-month patency rates for TASC class A, B, C, and D lesions were 89%, 73%, 72%, and 63%, respectively. Twelve-month patency rates for TASC class A, B, C, and D lesions were 89%, 58%, 51%, and 45%, respectively. CONCLUSIONS: Duplex-guided balloon angioplasty and stent placement seems to be a safe and effective technique for the treatment of infrainguinal arterial occlusive disease. Technical advantages include direct visualization of the puncture site, accurate selection of the proper size balloon and stent, and confirmation of the adequacy of the technique by hemodynamic and imaging parameters. Additional benefits are avoidance of radiation exposure and contrast material.

We have noted a significant incidence of pulmonary embolism (PE) and mortality associated with upper extremity deep venous thrombosis (UEDVT). Since there is an association between site of lower extremity DVT (LEDVT) and PE, we hypothesized that there might also be a correlation between site of UEDVT and PE with associated mortality. To further elucidate this hypotheses, we analyzed the mortality and incidence of PE diagnosed with subclavian/axillary/internal jugular vein thrombosis during an 11-year period at our institution and compared the data to those of patients diagnosed with brachial DVT. We studied 598 patients diagnosed with acute internal jugular, subclavian, axillary, or brachial DVT by duplex scanning. The patients were divided into three groups based on the most proximal location of the thrombus: group I, UEDVT involving the subclavian or axillary veins (n = 467); group II, isolated internal jugular DVT (n = 80); group III, brachial DVT alone (n = 52). Mortality rates at 2 months were 29%, 25%, and 21% for each group, respectively. The number of patients diagnosed with PE by ventilation/perfusion scans in groups I, II, and III, respectively, were 5%, 6.25% and 11.5% (p = 0.13). Furthermore, stratification by risk factors failed to demonstrate factors associated with increased 2-month mortality. Contrary to the initial hypothesis of a relationship between the site of thrombosis and the incidence of PE and mortality, these data demonstrated no statistical differences in mortality or incidence of PE among the groups studied. Additionally, these data suggest that brachial vein thrombosis is a disease process related to comparable associated mortality and morbidity similar to other forms of UEDVT. Based on these data, we suggest that UEDVT may be thought of as a marker for the severity of systemic illness of the patient rather than just as a cause of venous thromboembolism.

The clinical importance of upper extremity deep venous thrombosis (UEDVT) has been increasingly demonstrated in recent literature. Not only has the risk of pulmonary embolism from isolated upper extremity DVT been demonstrated, but a significant associated mortality has been encountered. Examination of this group of patients has demonstrated the existence of combined upper and lower extremity deep venous thrombosis (DVT) in some patients who exhibit an even higher associated mortality. As a result of this information, it has become the standard practice at this institution to search for lower extremity DVTs in patients found to have acute thrombosis of upper extremity veins. Since January 1999, there have been a total of 227 patients diagnosed with acute UEDVT. Within this group, 211 (93%) patients had lower extremity studies; 45 of these 211 (21%) had acute lower extremity DVTs by duplex examination in addition to the upper extremity DVTs. Overall, there were 145 women, 66 men, and the average age was 70 +/-1.2 (SEM); 22 of these patients had bilateral lower extremity thrombosis (LEDVT), and 8 patients were found to have chronic thrombosis of lower extremity veins. Of the patients with bilateral upper extremity DVTs, there were 3 with bilateral LE acute DVTs. Finally, 8 of the remaining 166 patients (5%) with originally negative lower extremity studies were found to develop a thrombosis at a later date. These data serve to confirm previous studies, on a larger scale, that there should be a high index of suspicion in patients with UEDVT of a coexistent LEDVT.

Owing to the overall poor medical health of patients with end-stage renal disease, we have sought alternatives to the use of general anesthesia for access procedures. Furthermore, since local anesthesia (1) does not offer the motor block that is sometimes desired and (2) can be difficult to maintain when a large amount of vein needs to be transposed, we examined whether regional blocks can be useful for the creation of new arteriovenous fistulae (AVF). From August 2002 to January 2005, 41 patients scheduled for AVF placement underwent a regional block with the use of a lidocaine and ropivacaine mixture using a nerve stimulator. Either axillary, interscalene, or infraclavicular blocks or a combination was used. Intraoperative duplex ultrasonography was used to assess the degree of venodilatation of the basilic and cephalic veins before and after the block. The site of each measurement was marked on the skin and selected by a clearly identifiable branch point. Each measurement was recorded three times and was made in the (1) native state, (2) after application of a tourniquet with opening and closing of the hand for 15 seconds, and (3) after placement of the block. The average age of the patients was 65 +/- 14 years (SD), with ages ranging from 33 to 91 years, and the prevalence of diabetes mellitus was 50%. Complete brachial plexus block was achieved in 34 patients (83%). Sensory block was accomplished within 10 to 15 minutes and usually lasted 4 to 6 hours. Motor block was accomplished in 10 to 25 minutes. Venodilatation was not noted in patients whose blocks did not work (n = 7) or whose vein was found to be phlebitic on exploration (n = 3). The degree of venodilatation noted as a percentage increase after application of the tourniquet compared with the native state for these 34 patients (in whom the block worked) was 37% for the distal cephalic, 31% for the midcephalic, and 32% for the midbasilic vein. The degree of venodilatation noted as a percentage increase after placement of the block compared with after tourniquet application for these 34 patients was 42% for the distal cephalic, 19% for the midcephalic, and 26% for the midbasilic vein. No instances of systemic toxicity, hematomas, or nerve injury from the block were noted. Accesses placed included 20 radiocephalic AVF, 8 brachiobasilic AVF, 8 brachiocephalic AVF, 2 arteriovenous grafts, 2 radiobasilic AVF, and 1 brachial vein AVF.Regional block is a safe and, in our opinion, preferred technique for providing anesthesia for upper extremity vascular surgery. The venodilatation observed is augmented compared with that using a tourniquet and may allow more options for access placements.

Acute limb-threatening ischemia from thrombosis may be the initial presentation of popliteal artery aneurysms (PAA) and is associated with amputation rates of 20-30%. Since contrast angiography may miss the diagnosis, the authors suspect that thrombosis of PAA may be an underappreciated cause of acute ischemia. Routine use of duplex arteriography (DA) may aid in the diagnosis and may help identify the outflow vessels with improved results. One hundred and nine patients (group 1) from 1994 to 1997 and 201 patients from 1998 to 2001 (group 2) presenting with acute limb-threatening ischemia were studied. None of the group 1 patients underwent preoperative DA and no diagnosis of acute popliteal artery aneurysm thrombosis was made. Ten patients with acute ischemia due to thrombosed popliteal artery aneurysms were identified in group 2 when preoperative DA was routinely performed. Urgent revascularization based on the results from DA was performed with use of autogenous saphenous vein in all patients. Six patients had functioning bypasses with a mean follow-up of 15.6 months. There were 3 deaths, 2 within 30 days and 1 after 2(1/2) years with functioning grafts. One patient was lost to follow-up. No major amputations were performed. Incidence of thrombosed popliteal artery aneurysms as the cause of acute limb-threatening ischemia is probably underestimated. Routine use of DA may provide the diagnosis and identifies the available outflow vessels. Contrary to previously published reports, urgent revascularization of an acutely ischemic extremity from thrombosed popliteal aneurysm can provide excellent rates of limb salvage.

PURPOSE: Patients requiring surgery are naturally attracted to shorter incisions because they tend to cause less pain and are esthetically more appeasing. To substantially shorten the length of standard skin incisions (4 to 7 inches) for carotid endarterectomy (CEA), we used preoperative duplex scanning to outline the carotid bifurcation as well as to determine the extent of disease in both the internal and common carotid arteries. METHODS: During the last 21 months, 265 consecutive primary CEAs were performed in 253 patients (mean age 72 +/- 10 years) at a single institution. Of these, 142 were men (56%). Hypertension, coronary artery disease, diabetes mellitus, smoking, and chronic renal failure were present in 81%, 44%, 43%, 28%, and 19% of the patients, respectively. Neurologically asymptomatic patients accounted for 71% of the cases. All patients received general anesthesia. Duplex-assisted skin markings of the diseased carotid artery were performed after proper patient positioning on the operating table. Synthetic patches were routinely used, and intraluminal shunts were deemed necessary by low stump pressures in 64 cases (24%). Completion duplex scanning was performed in all cases. RESULTS: The length of the longitudinal skin incision varied from 0.8 to 3.5 inches (average 1.4 +/- 0.5 inches). It was < or = 1 inch in 56 cases (21%), 1.1 to 1.5 inches in 110 (42%), 1.6 to 2 inches in 85 (32%), and 2.1 to 3.5 inches in the remaining 14 cases (5%). Intraluminal shunts were required in 9 (16%), 18 (16%), 29 (34%), and 8 (57%) of the cases, respectively. Incisions were longer in cases requiring an indwelling shunt (1.6 +/- 0.6 inches vs 1.4 +/- 0.4 inches) (P < .0001). The average patch length was 1.3 +/- 0.3 inches (range, 0.7 to 2.6 inches). The skin incision averaged 1.54 +/- 0.45 inches for the first 133 cases and 1.35 +/- 0.45 inches for the remaining 132 cases (P < .0001). Technical defects occurred in 10 cases (3.8%). The overall incidence of ipsilateral stroke and death was 1.9% and 0%. There were no technical defects or strokes in patients with the shortest incisions (< or = 1 inch). Overall, there were three transitory peripheral nerve injuries (1.1%). A comparative analysis with 265 consecutive CEAs performed immediately before this series without duplex-assisted skin markings revealed no significant differences in age (71 +/- 11 years), incidence of neurologically symptomatic patients (26%), sex (60% men), shunt use (24%), and major technical defects (3%). Also, postoperative transitory peripheral nerve injury (0.8%), stroke (0%), and death (0%) were not significantly different from the duplex-assisted group. It is of interest to note that none of the former cases was performed with a skin incision < or = 2 inches. CONCLUSION: Most CEAs (95%) can safely be performed with < or = 2-inch skin incisions. Pre-CEA duplex-assisted skin marking is a novel approach that confirms the side of the operation, localizes the disease, and minimizes the magnitude of the operation via shorter, more esthetically pleasing incisions.

BACKGROUND: The technique of balloon angioplasty of infrainguinal arteries requires standard arteriography and fluoroscopic guidance. We attempted to perform this procedure under duplex guidance to avoid the use of nephrotoxic contrast material and radiation exposure in patients with renal insufficiency. METHODS: Over 16 months, 28 patients (17 men) with serum creatinine levels of 1.5 mg/dL or more underwent 37 lower extremity duplex-guided balloon angioplasties at our institution. Ages ranged from 58 to 92 years (mean +/- SD, 74 +/- 9 years). Disabling claudication was the indication in 24 cases (65%), and critical ischemia, in 13 cases. Preoperative duplex arterial mapping showed severe superficial femoral artery and/or popliteal artery stenoses in all cases. No arterial occlusions were treated in this series. Seven procedures (19%) were performed for restenosis. The ipsilateral common femoral artery was cannulated in 32 cases (86%), and the contralateral common femoral artery, in 5 cases (14%), under direct duplex visualization. Contralateral common iliac artery cannulations were performed with the help of fluoroscopy. By using sonographic visualization, a guidewire was directed into the origin of the superficial femoral artery, across the diseased segment, and into the popliteal artery. The diseased segment was then balloon-dilated. Balloon diameter and length were chosen according to arterial measurements obtained by duplex scan. Plaque dissections and recoils causing stenosis of 30% or more, a peak systolic velocity ratio of 2 or more, or both were stented under duplex guidance. Arterial duplex examinations and ankle/brachial indexes were obtained before hospital discharge, within 1 month after the procedure, and every 3 months thereafter. RESULTS: Thirty-day survival was 100%. Local complications included one open exploration for expanding hematoma. Technical success was achieved in all cases. Placement of intraluminal stents was deemed appropriate in 23 (62%) of 37 cases. The 1-month patency and limb salvage rates were 100%. Preprocedure and postprocedure ankle/brachial indexes ranged from 0.3 to 0.9 (mean +/- SD, 0.64 +/- 0.16) and 0.64 to 1.2 (mean +/- SD, 0.92 +/- 0.15), respectively (P < .0001). CONCLUSIONS: Duplex-guided balloon angioplasty seems to be a safe and effective technique that allows renal patients to experience continued limb salvage and relief from claudication without the risk of developing dye-induced acute renal failure. Other advantages include direct visualization of the puncture site, accurate selection of the proper size of balloon and stent, confirmation of the adequacy of the technique by hemodynamic and imaging parameters, and avoidance of radiation. Although this technique holds considerable potential, longer follow-up will help to fully evaluate its broader applicability.

OBJECTIVE: Balloon angioplasties of stenotic or occluded infrapopliteal arteries may be helpful in selected high-risk patients threatened with limb loss. Thus far, these procedures have demanded fluoroscopy and the injection of potentially nephrotoxic contrast material. Herein, we proposed a new alternative to avoid the harmful effects of radiation exposure and the risk of acute renal failure. METHODS: Over the last 16 months, 30 patients (57% male) aged 74 +/- 9 years (mean +/- SD) had a total of 52 attempted balloon angioplasties of the infrapopliteal arteries in 32 limbs under duplex guidance. Indications for the procedure were critical ischemia in 20 limbs (63%), including rest pain, ischemic ulcers, and gangrene in 4 (13%), 10 (31%), and 6 (19%) limbs, respectively. Severe disabling claudication was an indication in the remaining 12 limbs (37%). All patients had concomitantly performed balloon angioplasties of the superficial femoral and popliteal arteries (28 cases) or the popliteal artery alone (4 cases). Balloon angioplasty of the infrapopliteal arteries was performed as an adjunct to improve runoff. Hypertension, diabetes, renal insufficiency, smoking, and coronary artery disease were present in 77%, 73%, 50%, 47%, and 37% of cases, respectively. There were 42 cases (81%) with infrapopliteal arterial stenoses (25 tibioperoneal trunks, 9 peroneal arteries, 4 anterior tibial arteries, and 4 posterior tibial arteries) in 26 limbs. The remaining 10 cases (19%) had infrapopliteal arterial occlusions (4 tibioperoneal trunks, 5 peroneal arteries, and 1 anterior tibial artery) in 6 limbs. All these cases were combined with more proximal endovascular procedures (21 femoropopliteal stenoses and 11 femoropopliteal occlusions). All patients had preprocedure duplex arterial mapping and ankle/brachial index (ABI) measurement. Local anesthesia with light sedation was used in all cases. The common femoral artery was cannulated under direct duplex visualization. Still under duplex guidance, a guidewire was directed into the proximal superficial femoral artery and distally, beyond the infrapopliteal diseased segment. The diseased segment was then balloon-dilated. Balloon diameter and length were chosen according to the arterial measurements obtained by duplex guidance. Completion duplex examinations were performed and postprocedure ABIs were obtained in all cases. RESULTS: Although the overall technical success was 94% (49/52 cases), it was 95% for those with stenoses (40/42 cases) and 90% for those with occlusions (9/10 cases; P < .5). Intraoperative thrombosis occurred in three infrapopliteal cases (two tibioperoneal trunks and one peroneal artery) and in one popliteal artery. All four cases were successfully managed with intra-arterial infusion of thrombolytic agents under duplex guidance. Overall, the preprocedure and postprocedure ABIs ranged from 0.4 to 0.8 (mean +/- SD, 0.58 +/- 0.15) and 0.7 to 1.1 (mean +/- SD, 0.9 +/- 0.16), respectively (P < .0001). Twenty-two (88%) of 25 patients experienced a significant (> 0.15) postoperative ABI increase. Overall 30-day survival and limb salvage rates were 100%. CONCLUSIONS: The proposed technique eliminates the need for radiation exposure and the use of contrast material, and it seems to be an effective alternative approach for the treatment of infrapopliteal occlusive disease. Additional advantages include accurate selection of the proper size of balloon and confirmation of the adequacy of the technique by hemodynamic and imaging parameters.