Renal revascularization by extra-anatomic bypass

Patients who suddenly become anuric and in whom no urinary obstruction is found should undergo arteriography both to confirm acute renal arterial occlusion and to plan surgical treatment. In acute renal arterial occlusion collateral circulation is often sufficient to maintain kidney viability and subsequent successful revascularization. Because there are no clinical or radiologic criteria to determine salvageability of the kidney, surgical exploration is advised in these patients. Such individuals who undergo successful renal revascularization often have gratifying return of renal function. Axillofemoral-renal bypass is suggested as a method to accomplish this objective. (J VASC SURG 1984;1:569-72.)     

Variability in hospital costs for carotid artery revascularization

Objective

The objective of this study was to understand drivers of cost for carotid endarterectomy (CEA) and carotid artery stenting (CAS) and to compare variation in cost among cases performed by vascular surgery (VS) with other services (OSs).

Cognitive function after carotid artery revascularization

Clinical investigations designed to contrast the efficacy of carotid endarterectomy (CEA) versus best medical therapy and CEA versus carotid artery stenting (CAS) in patients with carotid artery stenosis have been based on the traditional endpoints of stroke, myocardial infarction, and death. Cognitive function is being increasingly recognized as an important outcome measure that affects patient well-being and functional status. However, it has not been evaluated systematically in the context of carotid revascularization. A decline in cognitive function could occur from microembolic ischemia during surgical dissection (CEA) or intravascular instrumentation (CAS). It could also occur from hypoperfusion during clamping (CEA) or balloon dilation (CAS). Conversely, restoring perfusion could improve cognitive dysfunction that might have occurred from a state of chronic hypoperfusion. It is still unclear whether these complex interactions ultimately result in a net improvement or a deterioration of cognitive function. Furthermore, it is not known whether the 2 methods of carotid revascularization have a differential effect on cognitive outcomes. It is becoming increasingly clear, though, that there is a positive relationship between improvement in cognition and improvement in functional outcome of patients. Vascular surgeons will be well served to remain informed and even actively engaged in the development of this field if they wish to continue providing the high-quality, well-informed care they have traditionally offered to patients with carotid stenosis.     

Anatomic eligibility for transcarotid artery revascularization and transfemoral carotid artery stenting

ObjectiveTranscarotid artery revascularization (TCAR) has emerged as an alternative to transfemoral carotid artery stenting (tfCAS). We investigated the proportion of carotid arteries undergoing revascularization procedures that would be eligible for TCAR based on anatomic criteria and how many arteries at high anatomic risk for tfCAS would be amenable to TCAR.MethodsWe performed a retrospective review of consecutive patients who underwent carotid endarterectomy or carotid stenting between 2012 and 2015. Patients were excluded if computed tomography angiography of the neck was not performed within 6 months of the procedure. We assessed TCAR eligibility on the basis of the instructions for use of the ENROUTE Transcarotid Neuroprotection System (Silk Road Medical, Sunnyvale, Calif) and high anatomic risk for tfCAS on the basis of anatomic factors known to make carotid cannulation more difficult or hazardous.ResultsOf the 118 patients and 236 carotid arteries identified, 12 carotid arteries were excluded for presence of an occluded internal carotid artery (ICA). Of the remaining 224 carotid arteries, 72% were eligible for TCAR on the basis of the instructions for use criteria; 100% had 4- to 9-mm ICA diameters, 100% had ≥6-mm common carotid artery (CCA) diameter, 75% had ≥5-cm clavicle to carotid bifurcation distance, and 96% lacked significant CCA puncture site plaque. In addition, 7% of carotid arteries had bifurcation anatomy unfavorable for stenting; thus, of the entire cohort of arteries examined, 68% were eligible for TCAR. Hyperlipidemia (odds ratio [OR], 6.7; 95% confidence interval [CI], 1.7-26; P < .01), chronic obstructive pulmonary disease (OR, 3.5; 95% CI, 1.5-8.3; P < .01), and older age (OR, 1.1; 95% CI, 1.0-1.1; P < .01) were independently associated with TCAR ineligibility, whereas white race (OR, 0.2; 95% CI, 0.0-1.0; P = .048) and beta-blocker use (OR, 0.3; 95% CI, 0.1-0.7; P < .01) were independently associated with TCAR eligibility. In addition, 24% of carotid arteries were considered to be at high risk for tfCAS for the presence of a type III aortic arch (7.6%), severe aortic calcification (3.3%), tandem CCA lesions (7.1%), moderate to severe stenosis at the carotid ostium (8.9%), and tortuous distal ICA precluding embolic filter placement (4.5%). Active smoking (OR, 4.4; 95% CI, 1.9-10; P < .01), hyperlipidemia (OR, 4.0; 95% CI, 1.2-14; P = .03), and older age (OR, 1.1; 95% CI, 1.0-1.1; P = .02) were independently associated with tfCAS ineligibility, whereas preoperative aspirin (OR, 0.1; 95% CI, 0.0-0.4; P < .001) or clopidogrel (OR, 0.3; 95% CI, 0.1-0.8; P = .01) use was associated with tfCAS eligibility. Of the arteries that were considered to be at high risk for tfCAS, 69% were eligible for TCAR.ConclusionsThe majority of carotid arteries in individuals selected for revascularization meet TCAR eligibility, making TCAR a viable treatment option for many patients.     

Superficial temporal artery-to-middle cerebral artery bypass grafting for cerebral revascularization

Superficial temporal artery-to-middle cerebral artery bypass procedures are an important tool in the armamentarium of cerebrovascular surgeons for the treatment of carotid occlusion and revascularization for complex aneurysms and brain tumors. This article enumerates the essential steps in performing superficial temporal artery-to-middle cerebral artery bypass procedures. The nuances of this technique reflect the extensive experience of the senior authors.     

Carotid ligation for the treatment of carotid artery aneurysms

Summary Carotid ligation was performed in a series of 30 consecutive cases of infraclinoid aneurysms, of which 6 had not ruptured, and 9 cases of supraclinoid aneurysms. Fifteen of the ruptured aneurysms were operated on before, and 18 after, the eleventh day after bleeding. The internal carotid artery was primarily ligated in four cases, with two deaths, and in one case lasting hemiparesis occurred. In the rest of the cases, the common carotid artery was primarily ligated without operative mortality. After varying intervals, the internal carotid artery was ligated both in the neck and intracranially in 25 cases. In three cases late complications occurred due to embolus and thrombosis, resulting in one death. In four cases there were transient symptoms caused by insufficient cerebral circulation.The cerebral circulation was investigated in 23 cases using an intravenous isotope technique before and after ligation of the common carotid artery. In each of the cases the circulatory values were sufficient, with a slight diminishing of the flow on the ligated side. After ligation of the internal carotid artery at a later stage the flow in both hemispheres increased. This finding has been interpreted as being due to the interruption by internal carotid ligation of the retrograde internal carotid flow that occurs after common carotid ligation. In five cases aorto-cervical angiography was performed some months after ligation of the common carotid artery, and in four a retrograde flow in the internal carotid artery on the ligated side was shown. In accordance with the results obtained suggestions are made for carotid ligation in the treatment of carotid aneurysms not accessible for neck ligation.     

Late rheoencephalographic assessment of the cerebral circulation after ligation of the common carotid artery

Summary A series of 17 patients was investigated following common carotid ligation. The period between operation and examination ranged from 2–7 years. Cerebral circulation was estimated by use of the rheoencephalographic method.Statistical analysis of the reg plot was performed by comparing an age-matched normal population with patients. A comparison was also made of the ligated and nonligated sides for the patients. The following results were obtained: a significant decrease in the amplitude of the reg waves, an extension in the anacrotic part of the wave, and a decrease in the angle of its inclination. This was intensified more on the side of the common carotid ligation.These findings may suggest that after common carotid ligation the cerebral circulation is changed for a long period of time. They would also seem to indicate that postoperatively, the cerebral circulation does not return to normal—if it ever does.     

A modified extra-anatomic route for revascularization of the lower extremity

Occasionally, the standard medial approach to the popliteal trifurcation and tibial vessels is unusable because of infection in the area. When urgent revascularization is required, an alternative approach must be found. This report describes such an approach, with the use of a lateral tunnel from the calf to the groin and a posterior access to the tibial vessels. This technique was used successfully in our case.     

Indications for revascularization in patients with internal carotid artery stenosis

Three different strategies should be associated for ischaemic stroke prevention in patients with internal carotid artery stenosis: vascular risk factors control, anti-thrombotic agents, and carotid revascularization. Patients are selected for carotid revascularization on the basis of the presence of clinical symptoms and degree of stenosis. The optimal indication for carotid surgery is a severe recently symptomatic stenosis, since the benefits are marginal in high-grade asymptomatic stenosis, and in moderate symptomatic stenosis. Angioplasty with endoprothesis is an alternative to surgery, but it must be restricted to symptomatic stenosis either in randomized trials, or in severe stenosis in patients in whom surgery is contra-indicated.     

Stepwise revascularization by carotid endarterectomy after balloon angioplasty for symptomatic severe carotid artery stenosis

The authors report a novel stepwise carotid revascularization method to prevent perioperative complication. A 68-year-old man presented with left hemiparesis and dysarthria caused by severe stenosis of the right cervical internal carotid artery. According to the preoperative cerebral blood flow evaluation and plaque characterization, the patient was at risk for postoperative hyperperfusion and ischemic complications after carotid artery stenting. Initially, the patient underwent percutaneous angioplasty using an undersized balloon. Fifteen days later, the patient underwent a carotid endarterectomy. The surgical specimen obtained during the carotid endarterectomy showed the presence of typical vulnerable plaque. Of note was the complete preservation of the thin fibrous cap. The postoperative single-photon emission tomography images showed no signs of hyperperfusion, and the patient developed no neurological symptoms after each of the procedures.     

Simplified splanchnic artery revascularization using extra-anatomic bypass grafts: a report of ten cases.

Revascularization of the superior mesenteric artery or renal artery is frequently complicated by concomitant atherosclerotic disease in the adjacent aorta. In ten patients, extra-anatomic saphenous vein bypass grafts to the splanchnic vessels were constructed and inflow was obtained from the external iliac artery. All patients recovered without complication and have had functioning grafts on follow-up arteriography. This extra-anatomic bypass provides a simple method for splanchnic artery revascularization.     

Extracorporeal circulation as an additional method for cerebral protection in simultaneous carotid endarterectomy and coronary artery surgical revascularization

Surgical management of patients with concomitant carotid and coronary artery stenosis remains controversial. Our policy was always to perform at the same time carotid endarterectomy (CE) and coronary artery bypass grafting (CABG), but it was also considered that extracorporeal circulation (ECC), because of full heparinization, hemodilution, pulsatile flow, and hypothermia could provide better cerebral protection during CE. Retrospective data of 124 patients undergoing simultaneous CE and CABGs between January 1994 and December 2001 were reviewed. CE was performed prior to ECC in 65 patients (Group 1-mean age: 70.4 years; sex ratio: 49 male/16 female) and under ECC, prior to CABGs in 59 patients (Group 2-mean age: 69.9 years; sex ratio: 46 male/13 female). Overall hospital mortality was 7.3% (9/124): cardiac-related in 5 patients, or due to septicemia (1 patient), or ARD syndrome (1 patient), or stroke in two others. Univariate analysis demonstrated overweight, unstable angina, and emergency to be significant risk factors. Bilateral carotid stenosis was a significant risk factor of neurologic event when CE was performed prior to ECC (p < 0.05). In Group 1, mortality was 9.2% (6/65), and the incidence of neurologic events was 10.7% (7/65), and was responsible for two of the early deaths in patients with bilateral carotid stenosis. In Group 2, mortality was 5.1% (3/59) but never related to CE, while the neurologic morbidity was 1.7% (1 transient ischemic attack). It is concluded that (1) hospital mortality in patients undergoing simultaneous CE and CABGs was mainly cardiac-related. (2) The combined approach of both localizations appears to be mandatory, when carotid stenosis, even asymptomatic, was hemodynamically significant, or with ulcerative lesions likely to be responsible for embolism. (3) CE, first performed under ECC, appears to be a safe procedure, combining, in terms of cerebral protection, the benefits previously called up. This approach is all the more interesting when carotid stenosis is bilateral; hypothermia < or = 28 degrees C during the carotid clamping time is obviously the optimal method for cerebral protection when ipsilateral or contralateral supply is reduced, or even absent.