Current training and practice of endovascular surgery: a survey

Endovascular surgery (EVS) has become of great interest to the vascular community. However, little data exist about the current status of training and utilization of EVS, thus prompting this survey. During a national vascular meeting, all participants (n = 132) filled out a 2-page questionnaire. Respondents (mean age 39 years, 87% male) were 68 vascular surgeons in practice (52%), and 64 fellows (48%), representing a significant fraction of trainees in North America. Practice location included university hospital (39%), private hospital/clinic (52%), and government hospital (8%). According to respondents, in their respective communities, most of the EVS was performed by radiologists (66%), followed by vascular surgeons (19%), cardiologists (13%), and vascular medicine physicians (2%). A majority of respondents (75%) currently perform EVS; surgeons in practice < 3 years had the highest rate (90%). Utilization rates among the nine interventions surveyed ranged from angiography (72%) and angioplasty (65%) to intravascular ultrasound (IVUS) (21%) and atherectomy (12%). Procedure totals showed that approximately 20% of fellows performed > 100 angiograms and 10% performed > 25 endovascular grafts/year, whereas nonfellows performed few of the latter. Most of the EVS (72%) was performed in the operating room with portable imaging equipment and EVS accounted for 14% of all vascular procedures. Most respondents (86%) believed that EVS would become a major component of vascular surgery and comprise 30% of their future practice. Seventy-six percent thought their training was insufficient and 85% said they would devote 3 months or less for further endovascular training. In conclusion, a vast majority of vascular trainees and surgeons are performing EVS, however, individual caseloads vary greatly. The belief that endovascular surgery will play an increasing role in vascular surgery practice is strong and interest in further training of short duration is widespread. Broader-based data collection and longitudinal studies on this issue are warranted.

Safety and efficacy of early surgical decompression of the thoracic outlet for Paget-Schroetter syndrome

The surgical treatment of Paget-Schroetter syndrome has evolved to include early thrombolytic therapy and an interval period of anticoagulation, followed by late surgical decompression of the thoracic outlet. More recently, we have developed an abbreviated course of therapy in which the thrombolytic therapy is followed by early surgical decompression during the same admission, then a period of anticoagulation. We compared early surgical decompression with the standard management protocol to determine safety and efficacy of the early treatment algorithm. Nine patients were treated with lysis and early operation. These were compared with the preceding nine consecutive patients treated with lysis and staged operation. Demographic data, risk factors, duration of thrombosis, lytic therapy, time to surgery, operative variables, and postoperative complications were analyzed. Our results showed that thrombolysis followed by early operation does not result in increased perioperative morbidity or mortality. Early surgical decompression of the thoracic outlet during the same admission as lysis is as safe and efficacious as the traditional (staged decompression) approach to Paget-Schroetter syndrome. Lysis followed by early surgical decompression should be considered a new standard of care in the management of Paget-Schroetter syndrome.

Selective botulinum chemodenervation of the scalene muscles for treatment of neurogenic thoracic outlet syndrome

Patients with thoracic outlet syndrome (TOS) who improve temporarily after anesthetic blockade of the anterior scalene muscles have been shown to improve after ultimate surgical decompressions at the interscalene triangle. Anesthetic blockade of the scalene muscles, even with the addition of steroids, however, rarely produces any prolonged relief as patients are awaiting definitive surgery. The present study was undertaken to determine if more effective and prolonged relief might be obtained with electrophysiologically and fluoroscopically guided selective injection of the scalene muscles with botulinum toxin, which has been used in the past for treating conditions associated with spasm of cervical muscles. In 14 of 22 patients (64%) with a clinical diagnosis of TOS, there was more than a 50% reduction of symptoms measured by a 101-point scale for at least 1 month after botulinum chemodenervation of the scalene muscles. Only 4 of the 22 patients (18%) had a 50% reduction of symptoms for at least 1 month after injection with lidocaine and steroids. In no patient were the results of lidocaine and steroid injection superior to botulinum chemodenervation. Chemodenervation had a mean duration of effect of 88 days. No significant side effects were encountered with botulinum chemodenervation except for mild transient dysphagia in two cases. These results appear to demonstrate that botulinum chemodenervation of the scalene muscles may be helpful in alleviating symptoms in patients with TOS awaiting definitive surgical decompression.

Endoscopic surgery for arterial occlusive disease

Endoscopic surgery is not a recent development. In fact, the application of the Edison light bulb to the cystoscope in 1883 was followed by widespread use of endoscopy. In 1910, Jacobeaus proposed the diagnostic use of the cystoscope for investigation of serous cavities, and in 1922, he reported lysis of pleural adhesions to promote artificial pneumothorax in 40 patients with pulmonary tuberculosis. For the next 30 years, the thoracoscope was widely used for pneumolysis in tuberculosis patients, but its use waned considerably after the development of effective antibiotic treatment for tuberculosis. With the advent of laparoscopy, endoscopy has become popular again and here we review the application of endoscopic techniques in cardiovascular surgery.

Carotid endarterectomy in a community hospital setting: a three-year experience

The need for all medical institutions that treat carotid artery occlusive disease to continuously monitor their surgical experience is quite evident. Nonetheless, a national survey in 1995 found that only 15% of physicians reported knowing the perioperative stroke rate at the hospitals where they perform or refer patients for carotid endarterectomy. Neurologic morbidity related to the performance of carotid endarterectomy has been continuously monitored at Howard County General Hospital for the past decade, but the true significance of this data could not be appreciated without a more comprehensive analysis of the clinical experience. The present study was undertaken with the intent of providing this information.

Endovascular, transperitoneal, and retroperitoneal abdominal aortic aneurysm repair: results and costs

PURPOSE

Contemporary treatment of abdominal aortic aneurysms (AAA) includes transabdominal (TA), retroperitoneal (RP), and endovascular (EV) repair. This study compares the cost and early (30-day) results of a consecutive series of AAA repair by means of these three methods in a single institution.

METHODS

A total of 125 consecutive AAA repairs between February 1993 and August 1997 were reviewed. Risk factors, 30-day morbidity and mortality rates, and hospital stay and cost were analyzed according to method of repair (TA, RP, EV). Cost was normalized by means of a conversion factor to maintain confidentiality. Cost analysis includes conversion to TA repair (intent to treat) in the EV group.

RESULTS

One hundred twenty-five AAA repairs were performed with the TA (n = 40), RP (n = 24), or EV (n = 61) approach. Risk factors among the groups (age, coronary artery disease, hypertension, diabetes, chronic obstructive pulmonary disease, and cigarette smoking) were not statistically different, and thus the groups were comparable. The average estimated blood loss was significantly lower for EV (300 mL) than for RP (700 mL) and TA (786 mL; P>.05). Statistically significant higher cost for TA and RP for pharmacy and clinical laboratories (likely related to increased length of stay [LOS]) and significantly higher cost for EV in supplies and radiology (significantly reducing cost savings in LOS) were revealed by means of an itemized cost analysis. Operating room cost was similar for EV, TA, and RP. There were six perigraft leaks (9.6%) and six conversions to TA (9.6%) in the EV group.

CONCLUSION

There were no statistically significant differences in mortality rates among TA, RP, and EV. Respiratory failure was significantly more common after TA repair, compared with RP or EV, whereas wound complications were more common after RP. Overall cost was significantly higher for TA repair, with no significant difference in cost between EV and RP. EV repair significantly shortened hospital stay and intensive care unit (ICU) use and had a lower morbidity rate. Cost savings in LOS were significantly reduced in the EV group by the increased cost of supplies and radiology, accounting for a similar cost between EV and RP. Considering the increased resource use preoperatively and during follow-up for EV patients, the difference in cost between TA and EV may be insignificant. EV repair is unlikely to save money for the health care system; its use is likely to be driven by patient and physician preference, in view of a significant decrease in the morbidity rate and length of hospital stay.

Endovascular interventions training and credentialing for vascular surgeons

This article reviews issues concerning the training and credentialing of vascular surgeons in the use of endovascular techniques in the peripheral vascular system. These guidelines update a prior document that was published in 1993. They have been rewritten to accommodate the rapid evolution that has occurred in the field and to provide the appropriate requirements that a vascular surgeon should fulfill to be competent in the basic skills needed to safely and effectively perform all presently accepted diagnostic and therapeutic endovascular procedures.

Lower extremity vascular reconstruction and endovascular surgery without preoperative angiography

BACKGROUND

Recent studies have shown the feasibility of performing lower extremity revascularization based on noninvasive vascular studies alone.

METHODS

We undertook a prospective study of patients with lower extremity ischemia who underwent revascularization without preoperative angiography. Preoperative evaluation was done with noninvasive studies including segmental pressures, ankle arm index, duplex scan, and selective use of magnetic resonance angiography. Intraoperative angiography and intra-arterial pressure measurements were used prior to revascularization. Standard patency analysis and follow-up examination were performed.

RESULTS

In all, 47 patients underwent 65 procedures (27 iliac, 38 infrainguinal) over a 3-year period. Intraoperative angiography and operative findings correlated with the noninvasive studies. There was one immediate failure, and life table analysis demonstrated primary patency rates of 92% for iliac reconstruction (29 months) and 82% for infrainguinal reconstruction (40 months).

CONCLUSION

Preoperative evaluation for lower extremity revascularization utilizing only noninvasive vascular testing gives satisfactory results and is a safe and potentially durable alternative to routine preoperative angiography in most cases.

Thoracic outlet neurovascular compression: approaches to anatomic decompression and their limitations

Surgical management of thoracic outlet syndrome (TOS) has evolved to include multiple approaches for anatomic decompression. The relevant anatomy and review of different operative approaches are presented. The supraclavicular and transaxillary approaches are the most commonly used, and each has relative advantages. A working knowledge of these approaches and their limitations will aid in successful management of TOS.

Thoracoscopic sympathectomy: techniques and outcomes

Thoracic sympathectomy is an important option in the treatment of palmar hyperhidrosis and pain disorders. Earlier surgical procedures were highly invasive with known morbidity, acceptable outcome, and established recurrence rates that were the limitations to considering surgical treatment. Thoracoscopic sympathectomy is a minimally invasive procedure that allows detailed visualization of the sympathetic ganglia and minimal postoperative morbidity; however, outcome studies of this technique have been limited. The authors treated 39 patients with 60 thoracoscopic procedures, and the outcomes in this small series were equivalent to previously established open surgical techniques; however, operative moribidity rates, hospital stay, and time of return to normal activity were substantially reduced. Complications and recurrence of symptoms were also comparable to previous reports. Overall patient satisfaction and willingness to repeat the operative procedure ranged from 66 to 96% in all patients. Patients and physicians can consider minimally invasive thoracoscopic sympathectomy procedures as an option to treat sympathetically mediated disorders because of the procedure's reduced morbidity and at least equivalent outcome rates in comparison to other treatments.

Transluminal balloon angioplasty, stents, and atherectomy

Arterial bypass grafting for occlusive disease is still considered the gold standard in the treatment of arterial occlusive disease. However, less invasive methods are available for select patients. Percutaneous balloon angioplasty has been shown to be effective in focal iliac artery stenosis, with patency rates of 50% to 90% at 5 years. Patency rates for femoropopliteal lesions are generally less than 50% at 2 years. Complications seen with balloon angioplasty often can be treated with arterial stents. Stents can be categorized into balloon-expandable, which provide a rigid scaffold to support the artery, self-expanding, which exert radial force to resist external compression, and thermal expanding stents, which allow for the use of a smaller introducer sheath. Another treatment option is atherectomy, in which the offending lesion is removed instead of fracturing and dilating the lumen. Although overall initial results of atherectomy have not been favorable, short lesions with eccentric atheroma or intimal hyperplasia, such as those seen in dialysis access fistulas or vein graft stenoses, may respond well.

Laparoscopic aortobifemoral bypass

PURPOSE

To determine the potential benefits of applying laparoscopic techniques for the intraabdominal insertion of aortofemoral grafts and to compare results with those of conventional surgery.

METHODS

Having previously demonstrated the feasibility of a totally laparoscopic aortofemoral bypass technique using carbon dioxide peritoneal insufflation in a porcine model, we now report our first human experience with this laparoscopic technique in a 49-year-old man.

RESULTS

The patient's postoperative course was marked by his minimal requirements for analgesia, early ambulation, and discharge from the hospital in the morning of the third postoperative day.

CONCLUSIONS

The benefits of a laparoscopic approach to aortobifemoral bypass grafting in terms of financial savings and earlier rehabilitation in this patient was significant. This less-invasive procedure warrants further investigation.

Laparoscopic aortobifemoral bypass: a case report

In the past six years, laparoscopic surgery has gained widespread acceptance by both surgeon and patient. When compared to open surgical approaches, laparoscopic techniques for abdominal procedures lessen postoperative pain and morbidity, improve cosmesis, reduce hospital stay, facilitate early rehabilitation and return to normal activities. The application of laparoscopic techniques to intra-abdominal vascular procedures can be expected to provide similar benefits over conventional surgery.

Intraoperative vascular endoscopy: early and late results

In a prospective study, 60 consecutive cases of vascular endoscopy were analyzed to examine the role of angioscopy in infrainguinal vascular procedures. A total of 52 patients had 60 separate vascular endoscopy procedures performed as an adjunct to various vascular procedures; results of intraoperative arteriography were available in 38 of 60 cases. All patients were followed for at least 42 months. The 19 patients who underwent thrombectomy with angioscopy were compared with 19 age-matched control subjects who underwent infrainguinal thrombectomy without angioscopy to evaluate the influence of angioscopy on primary and secondary patency rates. Angioscopy allowed observation of 50 lesions; angiography failed to detect three. These findings altered surgical management in 24 cases (40%). Primary patency rates for the control and experimental thrombectomy groups were 38.8% and 6.5% at 42 months, respectively (p = 0.010 based on log-rank test). Secondary patency rates for the control and experimental groups at 42 months were 63.8% and 49%, respectively (p = 0.521). The limb salvage rate was 89% at 42 months for both groups (p = 0.973). Angioscopy provides the clinician with a direct view while he or she is performing vascular procedures. However, there was no statistical improvement in secondary patency and limb salvage rates. Furthermore, the use of angioscopy during thrombectomy may increase the propensity for subsequent intervention as evidenced by the frequency of changes in surgical management and the lower primary patency rate.

Indications and results of arterial stents for occlusive disease

The application of stents for treatment of peripheral arterial occlusive disease has gained widespread clinical use, but their safety and efficacy remain unclear. Stent technology is still evolving, and long-term follow-up data are sorely needed. Stents have had good success in providing a scaffold to maintain the intraluminal structure and patency of an artery. As such, stents appear to play a role in improving early results after failed or inadequate balloon angioplasty. However, stents do not prevent restenosis due to intimal hyperplasia. Furthermore, stents may be thrombogenic and prone to extrinsic compression in the peripheral position. Thus patency results are clearly worse in the femoral artery (47% at 3 years) than in the iliac artery (82-84% at 6-24 months). Furthermore, there is no evidence so far that stents improve long-term patency over standard balloon angioplasty without stents; and complication rates of stent procedures are generally 10%. Currently in the United States stents are approved for use in the iliac artery position. However, routine use of stents cannot be recommended until studies demonstrate that the results with stents are better than those with balloon angioplasty alone.

Current status of atherectomy for peripheral arterial occlusive disease

Atherectomy physically removes plaque by cutting, pulverizing, or shaving it in atherosclerotic arteries using a mechanical, catheter-deliverable endarterectomy device. Theoretically, atherectomy offers the following advantages over percutaneous transluminal angioplasty (PTA): It shows a greater immediate success rate with less dissection and acute occlusion, treats complex lesions, and reduces the restenosis rate. This article presents the unique features of four atherectomy devices designed to meet the above challenges: Simpson AtheroCath, Transluminal Extraction Catheter (TEC), Trac-Wright Catheter, and Auth Rotablator. The results, complications, and limitations reported by clinical investigators are discussed critically and realistically. A new device, the OmniCath, under investigative trial, is presented briefly. Clinical studies evaluating the Simpson AtheroCath have reported impressively high initial success rates (ranging from 82% to 100%) but disparate intermediate patency results (ranging from 35% to 84%). Complications associated with the device include hematoma, pseudoaneurysm, and distal embolization. Clinical studies show that the device is relatively ineffective for treating diffusely diseased and long-occluded lesions. Restenosis has also been a primary constraint of the Simpson device, with reported restenosis rates ranging from 11% to 55% at 6 months. The initial technical and clinical success rates reported with the TEC atherectomy device have been promising at 79% to 92%; however, short- and mid-term follow-up results have been either lacking or disappointing, with a reported patency of 67% at 6 months and 51% at 12 months. Furthermore, the problems of restenosis and reocclusion have limited its short-term benefits. The Trac-Wright catheter has demonstrated widely disparate technical success rates (from 58% to 100%) and clinical success rates (from 33% to 80%). Patency rates reported have been suboptimal, ranging from 25% to 68% at 6 months and 25% to 45% at 12 months. Furthermore, severe complications associated with the device include perforation, dissection, and embolization. Reocclusion also limits the applicability of the device. The reported immediate success rates of 72% to 94% using the Auth Rotablator are similar to those reported for other atherectomy devices. Patencies reported at 1 and 2 years are dismal, ranging from 31% to 61% and from 12% to 18%, respectively. Significant complications are associated with the device, including thrombosis, arterial spasm, hemoglobinuria, hematoma, and embolization. Contrary to previous studies and expectations, perforations and dissections have been encountered by some investigators. Late restenosis and reocclusion are also significant limiting factors of the Auth Rotablator. Atherectomy currently has limited applications for treatment of peripheral arterial occlusive disease. The intermediate- and long-term results obtained with the atherectomy devices are worse than those reported for PTA. Furthermore, all of the atherectomy devices have failed to reduce the restenosis and reocclusion rates from those reported for PTA. The problem of restenosis, reocclusion, and other complications must be solved before atherectomy can be used generally as an alternative to vascular reconstruction procedures such as PTA.

Cytotoxic effect of photodynamic therapy with Photofrin II on intimal hyperplasia

This study evaluates the effect of photodynamic therapy using Photofrin II on prevention and treatment of intimal hyperplasia in a rabbit model of common carotid artery balloon injury. An established model was used. One week after injury (inhibition arm) or 6 weeks after injury (treatment arm), each common carotid artery was exposed to continuous external laser irradiation 48 hours after a 5 mg/kg intravenous dose of Photofrin II (fluency = 7.6 joules/cm2, lambda = 630 nm). Histologic evaluation was performed 6 weeks following therapy in the inhibition arm and 1 day, 1 week, and 6 weeks following therapy in the treatment arm. Each arm included four subgroups (N = 10/subgroup): control, drug only, laser only, and drug plus laser. The first two subgroups underwent sham reoperations without laser exposure. In the inhibition arm no effect was seen on intimal cell density or area stenosis 6 weeks after photodynamic therapy. In the treatment arm intimal cell density was markedly diminished in the drug plus laser subgroup sacrificed 1 day and 1 week (but not 6 weeks) after treatment as compared to the remaining subgroups. There was no significant impact on area of stenosis. A marked acute cytotoxic effect of photodynamic therapy on intimal hyperplasia was verified in vivo in the treatment arm. The extracellular matrix was not affected. Cellular repopulation of the treatment zone was observed. No sustained benefit was seen in either the inhibition or the treatment arm. Refinements in dosimetry will be necessary to achieve long-term benefits.

Laparoscopic aortofemoral bypass. Initial experience in an animal model

OBJECTIVE

The study objective was to evaluate the feasibility of laparoscopic aortofemoral bypass in a porcine model.

SUMMARY BACKGROUND DATA

Laparoscopic techniques have been applied to numerous general and thoracic surgical procedures. Their application to vascular surgery has been virtually nonexistent. Open surgery for aortoiliac occlusive disease is accompanied by significant morbidity rates, and minimally invasive procedures have the disadvantage of reduced patency rates. Laparoscopic aortofemoral replacement has the theoretical advantage of long-term patency with reduced postoperative complications.

METHODS

Between January and September 1993, laparoscopic surgery was performed on 16 pigs: 6 underwent transperitoneal laparoscopic aortic dissection and vessel control alone; 7 underwent complete transperitoneal laparoscopic aortofemoral bypass; and 3 underwent a retroperitoneal approach. The aortic anastomosis was performed using a combination of sutures and titanium clips in an end-to-side fashion in five pigs, and a custom-made nonsutured graft was secured with use of an end-to-end method in five pigs. Femoral anastomoses were performed with the standard open technique.

RESULTS

Technical success was achieved in all 10 animals and with no major complications. Mean blood loss was 20 ml (range, 5-50 ml), and mean operative time was 2.45 hours (range, 2-4 hrs). On aortic-clamp release, 2 of the end-to-side anastomoses required additional sutures to stop bleeding between oversized staples, and 2 of the end-to-end anastomoses required additional ties to reinforce loose ties. All 10 grafts and anastomoses were patent and free of leaks after completion of the procedure.

CONCLUSIONS

Laparoscopic aortofemoral bypass is technically feasible in a porcine model. Further experimental work with new instrumentation and technical refinement will make laparoscopic surgery feasible for the treatment of vascular disease in humans.

Photodynamic therapy. Cytotoxicity of aluminum phthalocyanine on intimal hyperplasia

OBJECTIVE

To study the cytotoxic effect of photodynamic therapy (PDT) on myointimal hyperplasia (MIH) in 120 New Zealand white rabbits using the chromophore chloroaluminum phthalocyanine tetrasulfonate (APtS).

DESIGN

A common carotid artery (CCA) injury model was used to initiate MIH. Photodynamic therapy was administered 1 week after injury (inhibition arm) or 6 weeks after injury (treatment arm). The inhibition arm CCAs were harvested 6 weeks after therapy. The treatment arm CCAs were harvested 1 week or 6 weeks after therapy. Each evaluation included four subgroups (n = 10 each): control, drug only, laser only, and drug plus laser.

INTERVENTIONS

An established CCA balloon injury model was used. Photodynamic therapy was administered by exposing CCAs to continuous external laser irradiation 30 minutes after treatment with a 2.5-mg/kg intravenous dose of APtS (fluence = 25 J/cm2, lambda = 672 nm). The control and drug-only subgroups received sham reoperations without laser exposure.

MAIN OUTCOME MEASURES

Following harvest, the CCAs were evaluated for area of stenosis and cell density.

RESULTS

In the inhibition arm, no PDT effect was seen on intimal cell density or area stenosis. In the treatment arm, intimal cell density was markedly diminished (P < .05) in the rabbits in the drug-laser group that were killed 1 week but not 6 weeks after PDT compared with rabbits in the control, drug-only, and laser-only groups. Area stenosis was not significantly affected by PDT.

CONCLUSIONS

Marked acute cytotoxicity of PDT on MIH was verified in vivo in the treatment arm. No sustained benefit of PDT was seen in the inhibition or the treatment arms. Refinements in dosimetry will be necessary to achieve long-term benefit of PDT for MIH.