David L. Dawson

A Comparison of Cilostazol and Pentoxifylline for Treating Intermittent Claudication

PURPOSE We performed a randomized, double-blind, placebo-controlled, multicenter trial to evaluate the relative efficacy and safety of cilostazol and pentoxifylline. PATIENTS AND METHODS We enrolled patients with moderate-to-severe claudication from 54 outpatient vascular clinics, including sites at Air Force, Veterans Affairs, tertiary care, and university medical centers in the United States. Of 922 consenting patients, 698 met the inclusion criteria and were randomly assigned to blinded treatment with either cilostazol (100 mg orally twice a day), pentoxifylline (400 mg orally 3 times a day), or placebo. We measured maximal walking distance with constant-speed, variable-grade treadmill testing at baseline and at 4, 8, 12, 16, 20, and 24 weeks. RESULTS Mean maximal walking distance of cilostazol-treated patients (n = 227) was significantly greater at every postbaseline visit compared with patients who received pentoxifylline (n = 232) or placebo (n = 239). After 24 weeks of treatment, mean maximal walking distance increased by a mean of 107 m (a mean percent increase of 54% from baseline) in the cilostazol group, significantly more than the 64-m improvement (a 30% mean percent increase) with pentoxifylline (P <0.001). The improvement with pentoxifylline was similar (P = 0.82) to that in the placebo group (65 m, a 34% mean percent increase). Deaths and serious adverse event rates were similar in each group. Side effects (including headache, palpitations, and diarrhea) were more common in the cilostazol-treated patients, but withdrawal rates were similar in the cilostazol (16%) and pentoxifylline (19%) groups. CONCLUSION Cilostazol was significantly better than pentoxifylline or placebo for increasing walking distances in patients with intermittent claudication, but was associated with a greater frequency of minor side effects. Pentoxifylline and placebo had similar effects.

The effect of withdrawal of drugs treating intermittent claudication.

BACKGROUND Pharmacologic treatment for intermittent claudication is a management option. This study evaluated the effect of withdrawal of drug therapies, cilostazol and pentoxifylline, on the walking ability of peripheral artery disease patients. METHODS Single-blind placebo crossover from a randomized, double-blind trial; 45 claudication patients received either cilostazol 100 mg orally twice daily (n = 16), pentoxifylline 400 mg orally three times daily (n = 13), or placebo (n = 16) for 24 weeks. After 24 weeks of double-blind therapy, treatment for all groups was placebo only, and follow-up continued through week 30. Treatment efficacy was established with treadmill testing. RESULTS Profile analysis demonstrated a highly significant loss of treatment benefit after crossover (P = 0.001) for cilostazol-treated patients, but no significant change after crossover was observed with pentoxifylline. CONCLUSIONS Drug withdrawal worsened the walking of claudicants who had benefited from cilostazol therapy. This decline with crossover to placebo suggests that the initial improvement with cilostazol treatment was due to the drugs action. Withdrawal of pentoxifylline did not adversely affect walking.

Injuries to the portal triad

We reviewed the management and clinical course of 21 patients with extrahepatic injuries to the portal triad seen over the past 11 years at a Level I trauma center. These represented only 0.21% of patients with multiple trauma admitted during this time. Portal triad injury was never specifically diagnosed preoperatively. Extrahepatic bile duct injury occurred in 4 patients, portal vein injury in 14, and hepatic artery injury in 7; 3 patients had combined injuries. Eleven patients (52%) died, all due to uncontrolled hemorrhage from either an injured portal vein or associated intra-abdominal injuries. Management of the bile duct injuries included drainage alone, bile duct ligation, and Roux-Y hepaticojejunostomy. Survivors of portal vein injury were managed with lateral venorrhaphy. Ligation of the hepatic artery appeared to be optimal for injuries incurred by this vessel. Complications necessitating reoperation or percutaneous drainage procedures were encountered in 8 of 10 surviving patients (80%). Injuries to the portal triad are uncommon, difficult to diagnose, and technically challenging. Mortality is most directly related to uncontrolled intraabdominal hemorrhage, and salvage requires rapid control of bleeding as the first treatment priority.

Role of arteriography in the preoperative evaluation of carotid artery disease

This retrospective study was undertaken to determine the role of arteriography in the treatment of patients being considered for carotid endarterectomy. The results of preoperative classification of disease severity by duplex ultrasound and arteriography were compared, and the impact of arteriography on patient management was ascertained. We reviewed the records of 83 patients who had carotid surgery planned on the basis of their clinical history and duplex scan results and who then underwent arteriography. Duplex scan results agreed with the classification of stenosis by arteriography in 87% of evaluated sides and were within one category in 98%. In 87% of the cases reviewed, the clinical presentation and duplex scan findings were sufficient for appropriate patient management. In the instances that arteriography was useful (13%), the need for arteriography was evident when the duplex scan (1) was technically inadequate or equivocal; (2) showed an unusual distribution of disease, atypical anatomy, or a recurrent lesion; or (3) demonstrated an internal carotid artery with diameter-reducing stenosis of less than 50% in a patient with hemispheric neurologic symptoms despite antiplatelet therapy.

Does infrapopliteal arterial runoff predict success for popliteal artery aneurysmorrhaphy

BACKGROUND A 6-year experience with surgical management of popliteal artery aneurysms (PAAs) was examined to determine the influence of infrapopliteal outflow vessel patency on the long-term success of popliteal artery aneurysmorrhaphy. METHODS Arteriograms were reviewed to characterize the anatomy of the infrapopliteal arterial runoff. Regular clinical evaluation and prospective serial duplex scan surveillance assessed graft patency. RESULTS A total of 28 patients underwent 45 popliteal aneurysmorrhaphies. Elective repair was performed in 32 limbs (71%); emergency treatment was needed for 13 limbs (29%) because of acute limb-threatening ischemia. All patients were managed with PAA exclusion and reversed saphenous vein grafting. Only 20 limbs (44%) had a patent trifurcation with three continuous vessels to the ankle, 13 (29%) had two continuous tibial vessels, 10 (22%) had one patent runoff artery, and 2 (4%) had no vessel continuous to the foot. With a mean follow-up of 19.1 months, the 5-year primary graft patency by life-table analysis was 95 +/- 12.3%, with a 5-year assisted primary patency of 97 +/- 10.0%. One vein graft underwent elective secondary revision. Another graft thrombosed, requiring a secondary bypass. Outcome did not correlate with the status of the runoff anatomy. Limb salvage was 100%. CONCLUSION The use of autologous reversed vein grafting and attention to technical details yielded normal graft hemodynamics and excellent long-term patency and limb salvage despite the suboptimal runoff anatomy associated with PAAs.

The Role of Infrapopliteal MR Angiography in Patients Undergoing Optimal Contrast Angiography for Chronic Limb-threatening Ischemia

PURPOSE To determine the benefit of infrapopliteal magnetic resonance angiography (MRA) in patients with chronic limb-threatening ischemia who have undergone optimal contrast angiography (CA). PATIENTS AND METHODS Thirty-four patients (37 limbs) with limb-threatening chronic lower extremity ischemia underwent MRA and CA of the symptomatic extremity. Selective, vasodilator-enhanced digital subtraction angiography of the infrapopliteal vessels was possible for 34 limbs. Two vascular surgeons retrospectively formulated treatment plans based on CA. They then formulated treatment plans based on CA and MRA together. RESULTS CA clearly visualized 495 of 888 vascular segments as patent, while MRA clearly visualized 412 of 888 segments. Treatment plans differed for at least one of two surgeons in eight limbs, but MRA would possibly have improved clinical outcome in only one. The amount of inflow disease did not appear to influence segment visualization or treatment planning. In eight of 11 limbs that eventually required below- or above-knee amputation, CA clearly visualized more vascular segments than MRA. One patient developed renal insufficiency after CA. CONCLUSION Most patients undergoing optimal CA for chronic limb-threatening ischemia will not benefit from the addition of MRA. However, MRA should be considered when CA is suboptimal and when it is necessary to conserve contrast material.

Postcatheterization arteriovenous fistula: CT, ultrasound, and arteriographic findings

Abstract. The most common etiology of arteriovenous fistulae (AVF) in the lower extremity is iatrogenic, usually from diagnostic or therapeutic angiographic procedures. The finding of a palpable groin thrill, early venous opacification on contrast-enhanced abdominal-pelvic CT, and typical findings on duplex ultrasonography establish the diagnosis. Anatomic confirmation is then made by arteriography. A case of an incidentally discovered AVF in patient presenting to the Emergency Department is presented. Radiographic findings concerning and subsequent management of this patient are then discussed.