Indications for surgical treatment of angioaccess-induced arterial "steal"

BACKGROUND

Arterial "steal" is a well-known complication following proximal arteriovenous (AV) fistula, but its manifestations comprise a wide spectrum of symptoms and there are no clear indications for those patients who need surgical repair.

STUDY DESIGN

Among 180 consecutive AV fistulas of various configurations, with the brachial artery as the donor artery in all patients, 111 patients were studied retrospectively (group A) and 69 patients were studied prospectively (group B). Patient records were reviewed in group A, and the decision for surgical correction of limb-threatening steal was based on clinical grounds only. In group B, all patients were followed prospectively; postoperative systolic blood pressure measurements were obtained, and a systolic pressure index (SPI) was calculated (postoperative forearm systolic pressure divided by contralateral forearm systolic pressure). In patients with an SPI < 0.6, nerve conduction studies (NCS) were performed. The decision for operation in this group was based on clinical examination, SPI, and NCS.

RESULTS

Seven patients were operated on for steal-induced limb-threatening ischemia; in all seven patients, ischemia developed immediately after access construction. One additional patient with mild symptoms and deterioration in repeated NCS was considered a candidate for ischemic monomelic neuropathy and was successfully operated on 1 month later. The ligation-bypass technique was used in all patients, consisting of arterial ligature distal to the takeoff of the graft and short arterial bypass from a point proximal to the inflow of the access to a point just distal to ligation. In 94% of the patients, some degree of distal ischemia was detected (SPI < 0.8); patients with SPI < 0.5 were most likely to have impaired NCS.

CONCLUSIONS

Steal-induced limb-threatening ischemia necessitating immediate surgical repair occurred in 3.9% (7 of 180) of our patients. The decision for surgical correction of steal should be based on clinical examination. Nerve conduction studies may be useful in patients who have an SPI value < 0.5 to detect candidates who might develop ischemic monomelic neuropathy. In similar patients, surgical treatment of steal should be offered.

Patency of autologous and prosthetic arteriovenous fistulas in elderly patients

OBJECTIVE

To compare the patency of autologous and graft-bridging (prosthetic) arteriovenous (AV) fistulas in patients 70 years of age or more.

DESIGN

Non-randomised comparative study.

SETTING

University hospital, Greece.

PATIENTS

114 patients aged 70 years or more (mean 78) who required 135 consecutive angioaccess procedures during the 8-year period January 1990-December 1997.

INTERVENTIONS

68 autologous and 67 prosthetic procedures, 64 of the prosthetic procedures being proximal brachioaxillary AV arm grafts.

MAIN OUTCOME MEASURES

Primary and secondary cumulative patency rates and cumulative survival.

RESULTS

Life table analysis showed that the 3-year secondary patency (medium term patency) was significantly superior in the prosthetic group (58% compared with 44%, p = 0.04). Cumulative survival at 3-years was 21%.

CONCLUSIONS

A proximal brachioaxillary prosthetic AV graft is a good alternative as initial primary access in elderly patients who are not suitable for an autologous proximal AV fistula. At this age long term patency and conservation of proximal access sites are of minimum importance because of their limited life expectancy.

Influence of surgeons' specialty on the selection of vascular access for hemodialysis treatment

BACKGROUND/AIMS

Various patient-related factors could not explain the variability of access types across facilities in the published literature. The aim of this study was to investigate the influence of surgeons' specialty on access type selection for hemodialysis treatment.

METHODS

The directors (nephrologists) of all renal units in Greece (n = 92) were surveyed by a closed questionnaire.

RESULTS

The response rate was 75%. There was no statistically significant difference in the percentage of patients predominantly with autologous arteriovenous fistulae between units where only vascular surgeons were performing access surgery and those where either general surgeons or transplant surgeons were operating (mean value in all renal units 80.8%, range 43-97%). However, the difference between the three groups of renal units regarding their surgeons' ability to create complex access procedures and to correct complications (as an index of surgeons' skill) was statistically significant (p < 0.001).

CONCLUSION

The general surgeons of the new generation are not often using vascular surgical techniques and may have less opportunities to develop expertise in vascular access creation.

Endovascular Treatment of Infrarenal Isolated Abdominal Aortic Dissection with Application of the Kissing Stents Technique: A Case Report and Review of the Literature

Isolated abdominal aortic dissection (IAAD) is a rare form of aortic dissection involving usually the infrarenal part of the abdominal aorta. A 45-year-old male presented with lumbar pain and claudication. Computed tomography angiography (CTA) revealed an infrarenal IAAD extending to the left external iliac artery (EIA), causing ≥90% narrowing of the lumen. An endovascular approach was decided, with deployment of an aortic stent-graft and two balloon expandable stents in both common iliac arteries (IAs), applying the kissing stents technique. Post-surgical course was uneventful; 12 month follow-up showed excellent vessel patency. Endovascular therapy seems to be a feasible treatment option with promising long-term follow-up results.

Femoral-anterior tibial reconstructions using cuffed PTFE grafts: routing alternatives

BACKGROUND

The anterior tibial is the less often used artery for distal anastomosis in infrapopliteal bypass with synthetic grafts; however, several investigators argue against even an attempt to use non-autologous material for such distal reconstructions. Only few studies report patency rates mixing-up popliteal below-knee and various crural bypasses.

PATIENTS AND METHODS

Nineteen consecutive femoral-anterior tibial cuffed PTFE bypass grafts, either via the lateral (n = 15) or interosseous (n = 4) route, were inserted in a 10-years period.

RESULTS

The 1-year and 2-year primary patency rate was 71% and 53%, respectively. It is noteworthy that in one patient a graft positioned via the lateral route remained patient for ten years. No complications were observed regarding the routing methods, whatever increased operating time was required in the interosseous route cases. The 3-year cumulative survival rate for this particular group of patients was 32%.

CONCLUSIONS

Our data indicate that femoral-anterior tibial bypasses using cuffed PTFE grafts via the lateral route result in an acceptable medium-term patency. As such patients have a limited life expectancy, these procedures should be performed when an autologous vein is not available, as opposed to primary amputation.

Endovascular Treatment of Type Ib Endoleak after Evar Using the IBD Device: A Case Report

In the modern endovascular era, abdominal aortic aneurysm repair is still not free of complications with re-interventions following endovascular aneurysm repair (EVAR) being more common than with open surgical repair. A variety of endovascular, open surgical and combined techniques were described according to the anatomical considerations and general health of the patient to achieve the best possible result after these complications. In cases of type Ib endoleak following aorto-uni-lateral EVAR for an abdominal aortic aneurysm, the use of the internal branched device (IBD) constitutes a safe and effective technique.

Peroneal artery pseudo-aneurysm following blunt injury

The peroneal artery is injured less frequently than the popliteal and tibial arteries, because of its anatomical relationships. Pseudo-aneurysm of the peroneal artery due to a blunt injury is a rare complication. These injuries are usually occult, but more have been identified with the introduction and increasing use of angiography, following a high clinical suspicion of the trauma team involved. We report a case of peroneal artery false aneurysm following blunt trauma, presented with intermittent haemorrhage. In trauma, isolated peroneal artery pseudo-aneurysms, although rare, may occur. Early diagnosis can be confirmed by angiography and when less-invasive procedures cannot be applied, a posterior approach is an attractive surgical option in the management of proximal peroneal artery traumatic lesions.

The Significance of Medial Sural Artery Integrity in Popliteal Artery Trauma: A Case Report

Two patients with popliteal artery trauma who underwent secondary amputations due to refractory calf sepsis despite a patent arterial repair are presented in this case report. The medial sural artery, the main arterial supply of the medial head of the gastrocnemius, was surgically severed in both patients owing to the use of a continuous medial incision from the supra level to infragenicular level. The compromised arterial supply of the medial head of the gastrocnemius muscle may have contributed to the devitalization of the muscle and the subsequent calf sepsis, and it is speculated that this was related to the unfavorable outcome.

Fenestrated and Branched Stent Grafting in Complex Aneurysmatic Aortic Disease: A Single-Center Early Experience

BACKGROUND

The aim of this study is to present our early experience and highlight the technical difficulties associated with the use of fenestrated and branched stent grafts to treat patients with juxtarenal abdominal aortic aneurysm (AAA), pararenal AAA, and thoracoabdominal aortic aneurysms (TAAAs).

METHODS

A prospectively held database maintained at our department was queried for patients who have undergone branched and fenestrated stent grafting for AAA or TAAA treatment. Indication for repair, comorbidity precluding open repair, technical challenges associated with the repair, as well as operative mortality, morbidity, and reintervention rate were evaluated.

RESULTS

A total of 8 patients underwent repair with a fenestrated or branched stent graft. All patients had aneurysmal degeneration of the juxtarenal aorta, pararenal aorta, and thoracoabdominal aorta not suitable to standard endovascular techniques. Two patients had a prior aortic repair, a failed migrated stent graft, and an old surgical tube graft after an open repair. One patient had a type III TAAA and 1 patient had a postdissection TAAA type I. For all patients, target vessel success rate was 96.4% (27/28) and mean hospital stay was 6.0 days (range 3-21). Thirty-day and 1-year mortality were 0%. Mean follow-up was 23 months (range 7-45). Two endoleaks occurred, 1 type III and 1 type II, which were treated endovascularly. No death or major complication occurred during follow-up.

CONCLUSIONS

Fenestrated and branched endovascular stent grafts can be used to repair juxtarenal AAA, pararenal AAA, and TAAA in patients with significant comorbidities. However, several technical challenges have to be overcome due to the unique complex aortic pathology of each patient.

Surgical and endovascular intervention on internal carotid artery near occlusion

Therapeutic strategy for treating carotid artery near occlusion (CANO) has been controversial. The aim of this study was to review the literature concerning the invasive treatment of atherosclerotic CANO. A review was conducted of the English medical literature from 1980 to 2013 using PubMedand EMBASE database to find studies involving open or endovascular management of CANO. The search identified 20 reports describing invasive treatment of CANO encompassing 770 patients (77.7% men; mean age 66.3±5.2 years). A typical appearance of string sign was noted in nearly 60% of the patients. The vast majority (92.6%) were symptomatic. 479 (62.2%) patients underwent an open procedure, while 291 (38.8%) were treated endovascularly. The technical success rate for the endovascular procedures was 99%, while distal embolic protection devices were applied in most patients (66%). The 30 days procedural stroke rate was 2.1% and 2.4% for open and endovascular repair respectively. During a follow-up period spanning an average of approximately two years the ipsilateral cerebrovascular event rate was 5% and 1.2% for open and endovascular treatmentrespectively. Twenty five (5.2%) restenosis or occlusions were reported for the open procedures, while 13 (5.4%) were also documented for endovascular repair. The current literature concerning the invasive treatment of CANO is weak and cannot support any evidence based recommendation. The necessity to intervene as well as the best therapeutic strategy remains controversial. This review shows that the interventionon symptomatic CANO may consist a relatively safe and effective therapeutic strategy with low perioperative cerebrovascular morbidity for both treatment modalities, although durability and long-term outcomes should be further affirmed. The low incidence of this entity and the dearth of clear evidence support the need for a large multicenter registry to clarify the absolute indications for intervention and define the best therapeutic approach.

Arterial spasm mimicking superficial femoral artery trauma. Case report

The existence of traumatic arterial spasm in large arteries is questionable in current literature. We report a case of a 19-year old man with comminuted unstable femur fracture who presented with an ischemic foot. Localized arterial spasm was revealed in the middle portion of the superficial femoral artery triggered by the external pressure of a spicular bone segment was revealed by arteriography. Complete resolution of ischemic symptoms followed fracture reduction. Traumatic arterial spasm although rare does exist.

Phenylephrine induced aortic vasoconstriction is attenuated in hyperthyroid rats

BACKGROUND

Abnormal vascular responsiveness to vasoconstrictors may play an important role in peripheral vascular resistance in hyperthyroidism. The aim of the present study was to evaluate whether the vascular response to potassium chloride and phenylephrine is abnormal in a rat model of thyroxine-induced cardiac hypertrophy.

METHODS

Left ventricular hypertrophy was induced in Wistar rats by subcutaneous administration of L-thyroxine for two weeks ("THYR"), n=17. Animals treated with normal saline served as controls, ("NORM"), n=20. The thoracic aorta was dissected and cut into rings that were suspended in an isolated organ bath with Krebs-Henseleit buffer. Maximal tension, Tmax, in g was measured in response to KCl and PE at the highest concentration in rings with endothelium (+E) and without endothelium (-E) in both groups. Relaxation response (Relax percent) to acetylcholine administration was expressed as percent of the maximal tension induced by phenylephrine.

RESULTS

Left ventricular weight was 0.9 (SEM, 0.04) g for THYR group vs 0.7 (0.02) g for the NORM group, p<0.05. With KCl, Tmax was not different between the THYR and NORM groups with and without endothelium. With PE, there was a difference in Tmax between THYR+E and NORM+E, 1.2 (0.05) g vs 1.5 (0.09) g, p<0.05. Tmax was also different between THYR-E and NORM-E, 1.5 (0.08) g vs 1.7 (0.07) g, p<0.05. Relax percent was not significantly different between THYR+E and NORM+E (45.9 percent vs 42.8 percent, p>0.05).

CONCLUSIONS

We conclude that: a) Vascular tension of the thoracic aorta in response to PE is lower in thyroxine-treated rats as compared to controls, probably due to enhanced PE-induced vasorelaxation at high concentration. b) Relaxation response of the thoracic aorta to acetylcholine is not different between THYR and NORM groups.

Endovascular management of a late saccular aortic aneurysm after end-to-end repair of coarctation

Post-coarctation surgical repair aneurysm formation is observed rarely with end-to-end anastomosis technique. The redo surgery is associated with high mortality and morbidity rate. Although the minimal invasive method with stented grafts has been reported in only small number of patients, this could represent a valid alternative treatment. We present a case of successful endovascular treatment of a patient with a late post-coarctation repair saccular aneurysm.

Endotension. A review of current views on pathophysiology and treatment

Most aneurysms shrink after successful endovascular repair. It has been observed, however, that some aneurysms continue to enlarge despite apparent exclusion of the sac by an endograft device. Unexplained abdominal aortic aneurysm (AAA) enlargement in these circumstances appears to be associated with high pressures inside the sac, and the phenomenon has been termed endotension. This paper reviews current theories and experimental evidence regarding the possible mechanisms of causation of endotension, and early experiences with treatment.