Paul B. Kreienberg

Long-term outcomes of secondary procedures after endovascular aneurysm repair

PURPOSE This study evaluated the outcomes of secondary procedures after endovascular aneurysm repair (EVAR). METHODS From 2002 to 2009, 1768 patients underwent EVAR for treatment of 1662 elective (94%) and 106 emergent (6%) infrarenal abdominal aortic aneurysm (AAA) with a variety of Food and Drug Administration-approved and commercially available stent grafts. Postoperative follow-up included clinical examination, pulse volume recording, duplex ultrasound imaging, and computed tomography and magnetic resonance angiography at 1, 6, and 12 months, and yearly thereafter. Patients with type I and III endoleaks, unexplained endotension, limb occlusion, stent graft migration, with and without type I endoleak, and aneurysm rupture underwent secondary interventions. Type II endoleak at >6 months without a decrease in the aneurysm sac underwent translumbar embolization. Data were prospectively collected. RESULTS EVAR was performed in 1768 patients. During a mean follow-up of 34 (SD, 30.03) months, 339 patients (19.2%) required additional secondary procedures for aneurysm-related complications, including type I (n = 51, 15.0%), type II (n = 136, 40.1%), and type III (n = 5, 1.5%) endoleaks; endotension (n = 8, 2.4%), stent graft migration proximal fixation site (n = 46, 13.6%), stent graft iliac limb thrombosis or stenosis (n = 25, 7.4%), subsequent iliac aneurysm formation (n = 39, 11.5%), or aneurysm rupture after EVAR (n = 29, 8.6%). The mean age was 74 (SD, 9.15) years. Mean AAA size was 5.7 (SD 3.24) cm. Compared with secondary procedures for AAA rupture, the nonrupture patients had a significantly lower mortality (1.6% vs 17.2%, P < .05) and a higher likelihood of being managed by endovascular means (98.8% vs 44.8%, P < .05). When nonruptured EVAR patients required urgent secondary procedures for type I endoleaks and stent graft migration or limb thrombosis, the mortality was 6.0% vs 0.5% for elective procedures (P < .05). CONCLUSIONS Our long-term EVAR experience indicates that 18% of patients require additional secondary procedures, and most of these patients can be managed by endovascular means with an acceptable overall mortality of 2.9%. Most type I and II endoleaks can be successfully treated by transluminal embolization, and most patients with delayed aneurysm rupture after EVAR can be successfully managed by endovascular or open surgical repair.

Strategies to improve spinal cord ischemia in endovascular thoracic aortic repair: Outcomes of a prospective cerebrospinal fluid drainage protocol

PURPOSE Although endovascular repair of thoracic aortic aneurysm has been shown to reduce the morbidity and mortality rates, spinal cord ischemia remains a persistent problem. We evaluated our experience with spinal cord protective measures using a standardized cerebrospinal fluid (CSF) drainage protocol in patients undergoing endovascular thoracic aortic repair. METHODS From 2004 to 2006, 121 patients underwent elective (n = 52, 43%) and emergent (n = 69, 57%) endovascular thoracic aortic stent graft placement for thoracic aortic aneurysm (TAA) (n = 94, 78%), symptomatic penetrating ulceration (n = 11, 9%), pseudoaneurysms (n = 5, 4%) and traumatic aortic transactions (n = 11, 9%). In 2005, routine use of a CSF drainage protocol was established to minimize the risks of spinal cord ischemia. The CSF was actively drained to maintain pressures <15 mm Hg and the mean arterial blood pressures were maintained at >/=90 mm Hg. Data was prospectively collected in our vascular registry for elective and emergent endovascular thoracic aortic repair and the patients were divided into 2 groups (+CSF drainage protocol, -CSF drainage protocol). A chi(2) statistical analysis was performed and significance was assumed for P < .05. RESULTS Of the 121 patients with thoracic stent graft placement, the mean age was 72 years, 62 (51%) were male, and 56 (46%) underwent preoperative placement of a CSF drain, while 65 (54%) did not. Both groups had similar comorbidities of coronary artery disease (24 [43%] vs 27 [41%]), hypertension (44 [79%] vs 50 [77%]), chronic obstructive pulmonary disease (18 [32%] vs 22 [34%]), and chronic renal insufficiency (10 [17%] vs 12 [18%]). None of the patients with CSF drainage developed spinal cord ischemia (SCI), and 5 (8%) of the patients without CSF drainage developed SCI within 24 hours of endovascular repair (P< .05). All patients with clinical symptoms of SCI had CSF drain placement and augmentation of systemic blood pressures to >/=90 mm Hg, and 60% (3 of 5 patients) demonstrated marked clinical improvement. CONCLUSION Perioperative CSF drainage with augmentation of systemic blood pressures may have a beneficial role in reducing the risk of paraplegia in patients undergoing endovascular thoracic aortic stent graft placement. However, selective CSF drainage may offer the same benefit as mandatory drainage.

Carotid endarterectomy by eversion technique: its safety and durability.

SUMMARY BACKGROUND DATA The outcome of standard longitudinal carotid endarterectomy (CEA) can be measured by preservation of neurologic function with a low incidence of restenosis. Closure of the internal carotid arteriotomy with or without a patch may predispose to restenosis. Alternatively, transection of the internal carotid artery at the bulb with eversion endarterectomy allows expeditious removal of the plaque and direct visualization of the endpoint. Because the proximal internal carotid artery is anastomosed to the common carotid artery, this obviates the need for patch closure. The authors report their results with this technique in more than 2200 procedures. METHODS From May 1993 to March 1998, 1855 patients underwent 2249 CEAs using the eversion technique. During the same period, 410 patients had 474 CEAs by standard technique. Three hundred fifteen procedures in the eversion group and 65 procedures in the standard group were combined CEA and coronary artery bypass grafts. Most solo CEAs (97%) were performed in awake patients using regional anesthesia. Shunts were used on demand in 6% of CEAs. RESULTS The operative mortality rate was 1.02% (16/1575) in the solo eversion group and 2.2% (9/410) in the standard group. There were 18 permanent neurologic deficits (0.8%) in the eversion group and 11 (2.3%) in the standard group. Transient neurologic deficits occurred in 20 patients (0.9%) in the eversion group and 13 patients (2.7%) in the standard group. Of the 1855 patients, 1786 (96%) presented for duplex ultrasound follow-up. There were seven (0.3%) stenoses greater than 60% in the eversion group versus five (1.1%) in the standard group. CONCLUSIONS Eversion CEA can be performed safely with a low rate of stroke and death and a minimal restenosis rate in short- and long-term follow-up.

The incidence, natural history, and outcome of secondary intervention for persistent collateral flow in the excluded abdominal aortic aneurysm

OBJECTIVE The goal of abdominal aortic aneurysm (AAA) repair is the prevention of rupture. Exclusion of the infrarenal AAA by means of operation or endovascular graft placement is an alternative therapy to achieve this goal. However, thrombosis of the excluded aneurysm sac does not always occur and further intervention may be needed. This study examines the efficacy of available screening methods to detect the persistence of aneurysm sac flow and the outcome of secondary procedures to treat this problem. METHODS During the past 14 years, 1218 patients have undergone operative retroperitoneal exclusion of AAA. To date, 48 patients have been found to have persistent flow in the excluded AAA sac with duplex scanning. Twenty-seven patients underwent surgical intervention, and seven of these procedures were performed for rupture. Six patients have undergone treatment with interventional techniques (four successfully). The patients were evaluated for preoperative angiographic, anatomic, and comorbid factors that may have predisposed them to failed exclusion. Also, perioperative morbidity and mortality, estimated blood loss, and survival were assessed in the patients who required surgical treatment. RESULTS There were no perioperative parameters that correlated with postoperative persistent flow in the excluded AAA sac. The mean time to secondary intervention was 51 months (range, 2 to 113 months). Two patients had false-negative computed tomographic angiogram results, eight patients had false-negative angiogram results, and six patients had duplex scan examinations that had initially negative results that were then positive for flow in sac. Reoperation had a 7.4% mortality rate (two deaths) and a median blood loss of 2600 mL, as compared with 500 mL for primary procedures. CONCLUSION Secondary operations for patent excluded aortic aneurysm sacs have higher mortality and intraoperative blood loss rates than do primary procedures for AAA repair. The localization of branch leaks with computerized tomographic angiography, angiography, and duplex scanning were imprecise, and better methods are needed to adequately diagnose patent sacs. Expansion of AAA sac may be the only reliable factor.

Infrainguinal arterial reconstruction for claudication: Is it worth the risk? An analysis of 409 procedures☆☆☆

PURPOSE Infrainguinal reconstruction traditionally has been reserved for patients with limb-threatening ischemia. Surgery for debilitating claudication, however, has been discouraged as a result of the perceived fear of bypass graft failure, limb loss, and significant perioperative complications that may be worse than the natural history of the disease. In this study, the results of infrainguinal reconstructions for claudication performed during the past 10 years were evaluated for bypass graft patency, limb loss, and long-term survival rates. METHODS Data were collected and reviewed from the vascular registry, the office charts, and the hospital records for patients who underwent infrainguinal bypass grafting for claudication. RESULTS From 1987 to 1997, 409 infrainguinal reconstructions were performed for claudication (9% of all infrainguinal reconstructions in our unit). The patient population had the following demographics: 73% men, 28% with diabetes, 54% smokers, and an average age of 64 years (range, 24 to 91 years). Inflow was from the following arteries: iliac artery/graft, 10%; common femoral artery, 52%; superficial femoral artery, 19%; profunda femoris artery, 16%; and popliteal artery, 2%. The outflow vessels were the following arteries: 165 above-knee popliteal arteries (40%), 150 below-knee popliteal arteries (37%), and 94 tibial vessels (23%). The operative mortality rate was 0%, and one limb was lost in the series from distal embolization. The primary patency rates were 62%, 77%, and 86% for above-knee popliteal artery, below-knee popliteal artery, and tibial vessel reconstructions at 4 years, and the secondary patency rates were 64%, 81%, and 90%, respectively. Cumulative patient survival rates were 93% and 80% at 4 and 6 years as compared with 65% and 52%, respectively, for infrainguinal reconstructions performed for limb salvage. CONCLUSION Infrainguinal arterial reconstruction for disabling claudication is a safe and durable procedure in selected patients. These data indicate that concern for limb loss, death, and limited life span of the patients with this disease may not be warranted.

Outcomes of planned celiac artery coverage during TEVAR

OBJECTIVE Successful thoracic endovascular aneurysm repair (TEVAR) requires adequate proximal and distal fixation and seal. We report our experience of planned celiac artery coverage during endovascular repair of complex thoracic aortic aneurysms (TAA). METHODS Since 2004, 228 patients underwent TEVAR under elective (n=162, 71%) and emergent circumstances (66, 29%). Patients with inadequate distal stent grafts landing zones during TEVAR underwent detailed evaluation of the gastroduodenal arcade with communicating collaterals between the celiac and superior mesenteric artery (SMA) by computed tomography angiography and intraoperative arteriogram. If needed, in presence of a patent SMA and demonstration of collaterals to the celiac artery, the stent grafts were extended to the SMA with celiac artery coverage. Furthermore, instances when further lengthening of distal thoracic stent graft landing zone was needed to obtain an adequate seal, the SMA was partially covered with the endograft, and a balloon expandable stent was routinely deployed in proximal SMA to maintain patency. Outcome data were prospectively collected and analyzed retrospectively. RESULTS Thirty-one of 228 (14%) patients with TEVAR required celiac artery interruption; 24 (77%) had demonstrable collaterals to the SMA. Twelve (39%) of 31 patients underwent additional partial SMA coverage by stent graft, and proximal SMA stent. The majority of patients were females (n=20, 65%), the mean age was 74 years (range 55-87 years), and the mean TAA size was 6.5 cm. Postoperative complications included visceral ischemia in 2 (6%) patients, paraplegia in 2 (6%) patients, and death in 2 (6%) patients. All type 1b endoleaks (n=2, 6%) and type 2 endoleaks vial retrograde flow from the celiac artery (n=3, 10%) were successfully treated by transfemoral coil embolization. Over a mean follow-up of 15 months, there have been no other complications of mesenteric ischemia, spinal cord ischemia, SMA in-stent stenosis, or conversion to open surgical repair. CONCLUSIONS Our findings suggest that celiac artery coverage to facilitate adequate distal sealing during TEVAR with complex TAA is relatively safe in the presence of SMA-celiac collaterals. Pre-existing SMA stenosis can be successfully treated by balloon expandable stents during TEVAR, and endoleaks arising from distal stent grafts attachment site or via retrograde flow from the celiac artery can be successfully managed by transfemoral coil embolization. Although early results are encouraging, long-term efficacy of these procedures remains to be determined and vigilant follow-up is needed.

Alternative approach for management of infected aortic grafts

PURPOSE Prosthetic infection after aortic reconstructive surgery historically has been treated with extraanatomical bypass, graft excision, and aortic stump closure, but at the cost of substantial mortality and amputation rates. Alternatives to this strategy include in situ prosthetic replacement in the infected area, as well as autogenous reconstructions. Inherent to all of these procedures, however, is either the creation of an aortic stump, which carries a significant risk of subsequent blowout, or the placement of a bypass conduit in the infected field, thereby maintaining the potential for subsequent infectious complications. To avoid such problems, we have used retroperitoneal in-line aortic bypass with polytetrafluoroethylene through dean tissue planes. METHODS Since 1987 we have treated 16 graft infections in this manner. The surgical approach consisted of obtaining retroperitoneal proximal aortic control outside of the infected field (above or below the renal arteries), followed by infrarenal division and oversewing of the distal aorta. A polytetrafluoroethylene bifurcated graft was then sewn to the proximal aorta and tunnelled through the psoas sheath laterally to the profunda femoris artery on the ipsilateral side and via the space of Retzius to the contralateral appropriate femoral vessel, so as to avoid any contact with the infected areas. After the closure of the wounds, a plastic barrier was placed over all incisions and the patient was placed supine. The old infected graft was removed transperitoneally. Extensive cultures were taken at various sites to demonstrate no cross-contamination. RESULTS All patients were followed-up clinically and with tagged white cell scans at 6-month intervals. There were no immediate postoperative deaths and no amputations. One patient had a myocardial infarction and died at 5 months, and a second patient died at 2 months. Of the remaining 14 patients, none had recurrent sepsis and all have had negative Indium-labeled white cell scans in follow-up. Eleven (78%) are still alive, with a mean follow-up of 32 months (range, 20 to 106 months). CONCLUSIONS In-line aortic bypass for treatment of aortic graft infections yields excellent results and has become our treatment of choice in dealing with this difficult problem.

Repair of large abdominal aortic aneurysm should be performed early after coronary artery bypass surgery.

PURPOSE The surgical repair (coronary artery bypass grafting [CABG]) of symptomatic coronary artery disease (CAD) in patients with co-existent large abdominal aortic aneurysm (AAA) may result in an increased rate of AAA rupture after operation. Simultaneous CABG/AAA repair has been recommended by some surgeons, but with a somewhat higher mortality rate than staged repair. We reviewed the outcome of staged AAA repair that was performed early after CABG in patients with symptomatic coronary disease and AAA. METHODS The records of all the patients with symptomatic CAD that required CABG with large AAA (greater than 5 cm) were reviewed. In most patients, CABG was performed first, followed by AAA repair within 2 weeks. Patient demographics, severity of coronary disease, AAA size, interprocedure duration, and perioperative morbidity and mortality rates were examined. RESULTS Between 1991 and 1998, 1105 AAA repairs were performed. Within this group, 30 patients with AAA underwent CABG for symptomatic CAD. Mean AAA size was 6.6 cm (range, 5.0-10.0 cm). The median interprocedure interval between CABG and AAA repair was 11.5 days. There was no in-hospital AAA rupture during this interval. The patient group was comprised of 24 men and 6 women with a mean age of 71 years. There was no operative death after such staged AAA repair, and nonfatal complications occurred in seven patients (23%). During this period, seven patients had AAA rupture when they were sent home after CABG for recovery and intended AAA repair at a later date. CONCLUSION Staged elective AAA repair may be performed safely and effectively after CABG. Performance of these procedures with a short interprocedure interval may be preferable to the higher complication rate observed after combined procedures.

Upper extremity bypass grafting for limb salvage in end-stage renal failure.

OBJECTIVE Patients with end-stage renal failure and upper-extremity arterial occlusive disease sometimes have painful digital ulceration. We evaluated the efficacy of distal bypass grafting from the brachial artery for limb salvage in this setting. METHODS All patients with end-stage renal disease with painful digital ulceration or gangrene of the hand seen from 1992 to 2002 were evaluated with clinical examination and noninvasive studies. Those with evidence of occlusive disease underwent conventional angiography. Individuals with forearm occlusive disease underwent bypass grafting, from the brachial artery to either the distal radial artery or ulnar artery at the level of the wrist or proximal hand. Follow-up was scheduled at regular intervals, and included duplex scanning. Limb salvage and bypass graft patency were determined with life table analysis. RESULTS Over 10 years, 18 forearm bypass procedures were performed in 15 patients. The outflow artery was the radial artery in 15 procedures and the ulnar artery in 3 procedures. Bypass conduit was autogenous in all patients. No patient had a functioning arteriovenous fistula at bypass grafting; six limbs had previously occluded fistulas. Two bypass grafts (11%) occluded in the early postoperative period, with resultant progression of gangrene. In the remaining 16 grafts patency was maintained (mean follow-up, 18 months), with pain control and tissue healing. CONCLUSION Treatment in patients with renal failure with upper extremity occlusive disease may be facilitated with brachiodistal bypass grafting. Pain control and reversal of progression of hand necrosis can be achieved.

Timing of carotid endarterectomy in patients with recent stroke

BACKGROUND There is little objective data to support the conventional wisdom of waiting 4 to 6 weeks after stroke to improve surgical outcome of subsequent carotid endarterectomy (CEA). We have aggressively pursued CEA in patients after recent stroke; in this study we report our results. METHODS We performed 215 CEA procedures in 200 patients who presented with an indication of stroke within 6 months of CEA. Cervical block anesthesia was used 193 cases. The rest were performed with the patient under general anesthesia. RESULTS Perioperative stroke rate was 1.4% (3/215), and operative mortality was 2% (4/200) (stroke mortality = 3.4%). There were four early occlusions. Shunts were used in 13.9%, patch closure in 8.4%, and eversion endarterectomy in 48% of cases. There was no correlation between timing of surgery, extent of infarct on computed tomography/magnetic resonance imaging, and postoperative neurologic complications with the occurrence of postoperative stroke (p = NS). During the same period, 1,922 patients underwent CEA for indications other than stroke, with a perioperative stroke rate and mortality rate of 1.1%. CONCLUSIONS Selected patients presenting with a history of stroke and significant carotid artery disease can safely undergo early CEA with a mortality and morbidity comparable to patients undergoing CEA for other indications.