Electromagnetic field focusing (EFF) probe for intravascular endarterectomy. Preliminary feasibility study

Vaporization of atheromas in 10 human aorta segments immersed under flowing blood in vitro were done using the EFF probe. No increase in packed cells of the flowing blood following atheroma vaporization were noted suggesting absence of post vaporization debris. No damage to the aorta underlying the vaporized atheroma was noted on light microscopy suggesting well localized vaporization process. This study suggests that EFF probe might be a safe tool for intravascular endarterectomy.

Percutaneous atherectomy catheters

Percutaneous atherectomy catheters have been developed as an alternative to balloon angioplasty for the treatment of atherosclerotic disease. This article summarizes the preliminary experimental and clinical results with these catheters.

Extensive aorto-ilio-femoral endarterectomy with LeVeen plaque cracker

The authors present a series of 98 patients, who underwent an aorto-ilio-femoral endarterectomy according to the technique of LeVeen. The operative mortality was 1% with an adjusted early patency rate of 99%. For a total of 52 documented cases, erectile function was lost in 25%. Ejaculatory disorders were seen in 35 patients. With a mean follow-up period of 22 months (range 1 to 60 months) there were no occlusions in the aortoiliac group. Patency in the aortofemoral group decreased to 92.5% after 4 years. It is concluded that the results support continued use of the reported technique. A longer period of follow-up however is recommended to define its exact role in reconstructive surgery for aortoiliac occlusive disease.

Effect of pulse duration on selective ablation of atherosclerotic plaque by 480- to 490-nanometer laser radiation

The effect of varying pulse duration on selective ablation of human arterial plaque was evaluated by measuring ablation thresholds and ablation efficiencies on fresh human fibrofatty plaque, calcified plaque, normal intima, deep media, and adventitia using 480- to 490-nm laser radiation at 1, 8, and 50-microseconds pulse durations. For all tissues examined, the ablation threshold energy increased with increasing pulse duration, but the threshold for normal tissue ablation was approximately twice that of plaque at all pulse durations. Ablation efficiency was studied at a fluence that was twice the ablation threshold for plaque. For those fluences, normal intima had detectable ablation only at 50 microseconds. The ablation efficiency of fibrofatty plaque was minimally reduced with prolongation of pulse duration; however, there was a substantial decrease in the ablation efficiency of calcified plaque when the pulse duration was lengthened from 8 to 50 microseconds. These data show significant selective ablation of fibrofatty and calcified plaque at 1, 8, and 50 microseconds and suggest that the optimal pulse width for selective ablation of all plaque in the 480- to 490-waveband is less than 50 microseconds.

Extensive disobliteration of the aorto-iliac and common femoral arteries using the LeVeen plaque cracker

In 1978 LeVeen et al. described an original technique for extended aortobifemoral disobliteration using a retroperitoneal approach. This technique was introduced to Europe by Widdershoven and Willekens in 1977 and was adopted in Belgium by Suy and Nevelsteen in 1982 and in Spain by Cuesta and Bengoechea in 1984. A group of 228 patients treated by the LeVeen's method from 1982 to 1987 were followed-up for a mean of 21 months (1-54). Disabling claudication (66%) or more advanced ischaemia (34%) was the indication for treatment. An aorto-bifemoral endarterectomy was performed in 124 patients. Aorto-biiliac endarterectomy in 39, unilateral aortofemoral endarterectomy with a contralateral aorto-iliac endarterectomy in 17 and unilateral iliofemoral endarterectomy in 48 cases. There were seven postoperative deaths (3%) and an early thrombectomy had to be performed in 8 patients. There were 14 late deaths. Occlusion occurred in 11 patients giving a 3-year-patency rate of 97%. There were no late complications related to the technique. It is concluded that disobliteration using the LeVeen technique compares well with prosthetic grafting. Since this method does not require the use of foreign material the patient is protected from the complications sometimes seen after the insertion of prosthetic grafts.

The argon contact laser scalpel: a study of its effect on atherosclerosis

A new argon laser scalpel (ALS) that delivers radiation to tissue by direct contact was used to perform endarterectomies on atherosclerotic rabbit aortas in vivo. The resultant effects were compared to those induced by CO2 laser (CO2) and conventional surgical endarterectomy (END) to determine whether this instrument might be useful in the treatment of occlusive cerebrovascular disease. Light microscopy of the treated aortic segments revealed significantly more atheroma removed and less damage to the underlying media in the ALS segments compared to the CO2 segments. Electron microscopy showed that the ALS surface and distal intima-media interface were smoother and more even than those of the CO2 or END groups. Prostacyclin synthesis, as measured by 6-keto-prostaglandin F1a levels, was significantly reduced in the ALS compared to the END and control segments. These results indicate that the ALS is superior to CO2 in performing open laser endarterectomies, but such treatment places the atherosclerotic blood vessel at greater risk for thrombotic complications during the early postoperative period that does surgical endarterectomy. It is conceivable that a contact laser may be useful in the smooth welding of the distal edge of an atheroma (i.e., during carotid endarterectomy) and for the transcatheter ablation of surgically inaccessible obstructions of the cerebral circulation.

The argon "contact" laser scalpel: technical considerations

The authors describe the use of a new contact argon laser scalpel designed specifically for hand-controlled cutting and hemostasis. This instrument delivers energy precisely to targeted tissue and produces minimal damage to adjacent healthy structures. Potential clinical applications are discussed.

Modified Mayo-Adams self-retaining retractor for carotid endarterectomy

The authors describe the use of a Mayo-Adams self-retaining retractor modified for improved exposure of the distal internal carotid artery during carotid endarterectomy.

Experience with the vascular brush

The history and use to date of the vascular brush are briefly outlined. The development of this new instrument was made possible by fibre-optic vascular endoscopy, but its use and capabilities are apparently not yet widely known. We regard the brush as the common sense solution for producing smooth bores after various peripheral vascular procedures such as endarterectomy and late arterial and venous thrombo-embolectomy operations. As a reamer and a smoothing instrument it exerts a powerful yet safe and self-limiting action, due to the compliant, impaling effect of the bristles at low intra-luminal pressure. Broadly speaking, the use of the brush is indicated when the smooth Fogarty balloon catheter is no longer capable of removing resistant residual tissue. The use of this instrument on a wider scale, eventually in disposable form, would seem to offer considerable promise in peripheral vascular surgery.

[Femoro-popliteal endarterectomy using a pneumatic oscillator]

In patients with severe ischaemia from femoro-popliteal thrombosis, but without suitable vein for bypass, a synthetic or bioprosthesis is usually installed. This is a costly method giving statistically mediocre results. An alternative method is femoro-popliteal endarterectomy performed with rings that are made to oscillate by a pneumatic motor. The procedure requires 3 arteriotomies: one at each end and one in-between to insert rings of a different caliber. Arteriography is mandatory at the end of the operation. This type of endarterectomy is feasible only when blood flow is adequate upstreams, when the femoro-popliteal axis is not calcified and when at least one artery of the leg remains patent. The method is less expensive, and its early results apparently better than those of prostheses extending beyond the knee.

A new lightweight shunt clamp for use during carotid endarterectomy

A technique is described for using a modified Drake aneurysm clip as a lightweight vascular clamp for securing the distal end of an intraluminal shunt during carotid endarterectomy.

Extensive endarterectomy of the aorta, common and external iliac arteries, and common femoral arteries by a modified Le Veen method

It has been 8 years since Le Veen et al. described a new method of disobliteration of the distal aorta and iliac arteries. Since then no further reports have appeared in the literature. During the past 2 1/2 years we have treated 23 patients with severe ischemia of the lower limbs, caused in most cases by severe and multilevel arterial occlusions (types II and III), which included the infrarenal aorta, common and external iliac arteries, and common femoral arteries, with the method of Le Veen et al. with some modifications in the technique. A satisfactory revascularization was obtained in all patients. Similarly, there were no operative deaths or morbidity and no early or late arterial occlusions. We conclude that this method of arterial disobliteration has certain advantages over the much more widely used bypass grafting, deserves an extensive trial, and could in the future become a well-accepted procedure to treat extensive occlusions of the distal aorta, common and external iliac arteries, and common femoral arteries.

Safer shunt insertion during carotid endarterectomy

The use of shunts during carotid surgery may decrease the risk of perioperative stroke by allowing continued perfusion during the procedure. However, there are risks inherent with shunt usage that occur mainly during insertion. A brief clinical study illustrates the risk of shunt-induced emboli and a technique is described for safer shunt insertion.

Oscillating loop endarterectomy for peripheral vascular reconstruction

A new technique for endarterectomy of the aorta, iliac, femoropopliteal, and three distal vessels of the lower leg is a safe and predictable method of endarterectomy that has proved to be effective. By the use of this technique the superficial femoral artery and its collateral branches are opened, considerably increasing the blood flow to the lower leg. Increased knowledge concerning thrombogenic enzymes, released when cleavage of the arterial wall is performed, has led to the use of antiplatelet and anticoagulative drug therapy. This has significantly enhanced the patency of the endarterectomized vessel. Today, with many patients having the saphenous veins harvested for coronary bypass or needing these veins for future bypass surgery, it seems reasonable to perform an endarterectomy of the femoral artery.

[Clinical application of a Biballoon indwelling intraluminal shunt system for carotid endarterectomy]

Clinical applications of newly developed shunt system for carotid endarterectomy were described. The shunt is a silicone tube equipped with balloons at both ends (Biballoon indwelling intraluminal shunt). The blood leak from the gap between a shunt tube and the inner wall of the carotid artery is prevented by inflating balloons after shunt insertion. This shunt system was used in seven cases of cerebral infarction resulted from the carotid stenosis and was proved to be more convenient than other known shunts.

Another alternative in leg revascularization

Prosthetic grafts of various types have been the only alternative to revascularization of the leg when the saphenous vein is not used. Our complication rate with prosthetic grafts has led us to search for a different alternative. Long-segment endarterectomy of the iliac, femoral, and popliteal arteries has become a realistic procedure with the use of the Hall oscillating endarterectomy instrument. Although it may be difficult technically and more time-consuming than a usual bypass graft procedure, the results have been good. Fifty-eight procedures have been reported in 53 patients. Eighty-eight percent of the procedures were performed for limb salvage with a 5 percent operative mortality rate. There was an overall cumulative limb salvage rate of 88 percent. The cumulative patency rate with a follow-up of 5 to 24 months was 55 percent. Special emphasis has been placed on technical considerations and pitfalls of the procedure. The procedure is versatile and can be used in combination with a variety of both inflow and outflow procedures.

[Endarterectomy of the superficial femoral artery using an oscillating loop]

A short series of half closed endarterectomies of superficial femoral artery with oscillating ringstripper is presented. The technique used is described, and major problems are discussed. Results are published and confrontated with the clinical events. Three criteria are withheld for indication of this procedure: the superficial femoral artery has to be completely occluded and not calcifiated; the popliteal artery has to be angiographically normal; two out of three arteries below knee have to be permeable. The authors advocate oral anticoagulation for a relatively long postoperative period.

Indwelling double-balloon shunt for carotid endarterectomy. Technical note

The authors describe an indwelling intraluminal shunt for carotid endarterectomy. The device is equipped with balloons at both ends to prevent bleeding and to hold the tube in place. The design permits use of a small tube which facilitates insertion, and prevents intimal damage and limitation of exposure of arterial plaque.

Safe intraluminal shunting during carotid endarterectomy

The major complications associated with shunting include embolization at the time of insertion and shunt thrombosis. Increased technical difficulty of performing the endarterectomy with an inlying shunt hs also contributed to lack of surgeon acceptance. These problems can be minimized by using a short, flexible shunt with a sidearm attachment. The shortness enables the shunt to lie within the vessel, while the flexibility enables manipulation of the shunt to optimize exposure of all segments of the vessel. The sidearm allows flushing of both limbs and helps prevent embolization while providing a means for rapid assessment of shunt patency. The technique provides a safe and simple method of shunting during carotid endarterectomy.