Anatomic characteristics of abdominal aortic aneurysms presenting with delayed rupture after endovascular aneurysm repair.

OBJECTIVE: Endovascular aneurysm repair (EVAR) has become the mainstay of treatment for abdominal aortic aneurysms (AAAs) requiring repair. Delayed rupture after EVAR represents a rare but potentially fatal complication. The purpose of this study was to review the frequency and characteristics of patients presenting with secondary rupture and to define the relationship between rupture after EVAR and initial compliance with instructions for use (IFU). METHODS: This is a retrospective study of a prospectively maintained database. Patients presenting with delayed rupture after EVAR were identified from January 2002 to December 2014. Medical records and imaging were reviewed to define anatomic characteristics and compliance with IFU criteria. Demographics, comorbidities, preoperative imaging, and long-term outcomes were analyzed. Patients were divided into two groups according to compliance with IFU criteria. Outcomes included type of repair (open vs secondary endovascular) as well as perioperative morbidity and mortality. RESULTS: A total of 3081 patients underwent EVAR for AAA from 2002 to 2014. Of the 3081 patients, 45 experienced delayed rupture after EVAR. The mean time interval between initial repair and rupture was 38 months. All patients with delayed ruptures had a type Ia endoleak. Mean follow-up after secondary repair was 44.1 months, and overall mortality was 6.7% (n = 3). Patients were divided in two groups according to compliance with IFU criteria: within the IFU and outside the IFU. There was no significant difference in comorbidities between the two groups except smoking, which was more frequent in the outside the IFU group (25% vs 21%; P = .03). Patients repaired outside the IFU had a higher incidence of type Ia endoleak before presenting with a rupture (44% vs 6%; P = .001), more frequently required open repair (44% vs 12%; P = .002), and had higher perioperative mortality (10.3% vs 0%; P = .01). On review of preoperative computed tomography scans, the outside the IFU group had larger aneurysm sac diameters (7.2 vs 5.6 cm; P = .04), larger proximal neck diameters (28 vs 24 mm; P = .01), shorter proximal necks (12 vs 21 mm; P = .007), and a higher degree of neck angulation >40 degrees (56 vs 11%; P < .001). CONCLUSIONS: Delayed rupture after EVAR is a rare but potentially fatal complication. In patients presenting with secondary rupture, EVAR performed outside the IFU was associated with higher perioperative mortality and need for open repair. Careful selection of patients based on AAA anatomy and adherence to the IFU criteria may reduce the incidence of delayed rupture.

Regionalization of Emergent Vascular Surgery for Patients With Ruptured AAA Improves Outcomes.

OBJECTIVE: Safe and efficient endovascular aneurysm repair (EVAR) for ruptured abdominal aortic aneurysm (r-AAA) requires advanced infrastructure and surgical expertise not available at all US hospitals. The objective was to assess the impact of regionalizing r-AAA care to centers equipped for both open surgical repair (r-OSR) and EVAR (r-EVAR) by vascular surgeons. METHODS: A retrospective review of all patients with r-AAA undergoing open or endovascular repair in a 12-hospital region. Patient demographics, transfer status, type of repair, and intraoperative variables were recorded. Outcomes included perioperative morbidity and mortality. RESULTS: Four hundred fifty-one patients with r-AAA were treated from 2002 to 2015. Three hundred twenty-one patients (71%) presented initially to community hospitals (CHs) and 130 (29%) presented to the tertiary medical center (MC). Of the 321 patients presenting to CH, 133 (41%) were treated locally (131 OSR; 2 EVAR) and 188 (59%) were transferred to the MC. In total, 318 patients were treated at the MC (122 OSR; 196 EVAR). At the MC, r-EVAR was associated with a lower mortality rate than r-OSR (20% vs 37%, P = 0.001). Transfer did not influence r-EVAR mortality (20% in r-EVAR presenting to MC vs 20% in r-EVAR transferred, P > 0.2). Overall, r-AAA mortality at the MC was 20% lower than CH (27% vs 46%, P < 0.001). CONCLUSIONS: Regionalization of r-AAA repair to centers equipped for both r-EVAR and r-OSR decreased mortality by approximately 20%. Transfer did not impact the mortality of r-EVAR at the tertiary center. Care of r-AAA in the US should be centralized to centers equipped with available technology and vascular surgeons.

Chronic mesenteric ischemia outcome analysis and predictors of endovascular failure.

OBJECTIVE: Outcomes of open revascularization (OR) and endovascular revascularization (ER) for chronic mesenteric ischemia (CMI) were analyzed to identify predictors of endovascular failure. METHODS: A retrospective study was performed of all consecutive patients with CMI (161 patients, 215 vessels) treated from 2008 to 2012. Demographics, comorbidities, clinical presentation, etiology, and treatment modalities were compared. Outcomes included technical success, restenosis requiring reintervention, complications, mortality, and hospital length of stay. RESULTS: There were 116 patients who were first treated with ER (72%) and 45 patients with OR (28%). Overall mortality was 6.8% (11/161). Among the ER patients, 27 developed restenosis and required OR (23%). Patients treated with ER were older (73 vs 66 years; P = .014), had similar comorbidities, and had higher rate of short lesions (≤2 cm) on preoperative angiograms (23% vs 47%; P = .004). Primary patency at 3 years was higher in the OR group compared with the ER group (91% vs 74%; P = .018). Long-term survival rates were higher in the ER group (95% vs 78%; P = .003). Hospital length of stay and intensive care unit length of stay were shorter in the ER group (<.001). Perioperative mortality (30-day) was not statistically significant between the groups (5.2% vs 11%; P = .165). A subgroup analysis was performed between the patients with successful ER and failure of ER requiring OR. Patients with failure of ER had significantly higher rates of aortic occlusive disease (86% vs 49%; P = .005) and long lesions ≥2 cm on angiography (57% vs 12%; P < .001) that were close to the mesenteric takeoff. Perioperative mortality was higher in the ER failure group (15% vs 2%; P = .009). CONCLUSIONS: ER has similar perioperative mortality and shorter hospitalization but higher rate of restenosis requiring reintervention compared with OR. Patients with ER who required reintervention appear to have longer lesions as well as higher rates of aortic occlusive disease on preoperative angiography. Patients who crossed over from ER to OR had higher perioperative mortality than either primary open or endovascular patients. These findings may guide treatment selection in patients with CMI undergoing ER or OR.

The impact of hemodynamic status on outcomes of endovascular abdominal aortic aneurysm repair for rupture.

OBJECTIVE: To date, there are no published reports comparing hemodynamically (Hd)-stable and Hd-unstable patients with ruptured abdominal aortic aneurysms (r-AAAs) undergoing endovascular aneurysm repair (EVAR). This study evaluates outcomes of EVAR for r-AAA based on patient's Hd status METHODS: From 2002 to 2011, 136 patients with r-AAAs underwent EVAR and were categorized into two groups based on systolic blood pressure (SBP) measurements before EVAR: 92 (68%) Hd-stable (SBP ≥ 80 mm Hg) and 44 (32%) Hd-unstable (SBP <80 mm Hg for >10 minutes). All data were prospectively entered in a database and retrospectively analyzed. Outcomes included 30-day mortality, postoperative complications, the need for secondary reinterventions, and midterm mortality. The effect of potential predictors on 30-day mortality was assessed by χ(2) and logistic regression. RESULTS: Of the 136 r-AAA patients with EVAR, the Hd-stable and Hd-unstable groups had similar comorbidities (coronary artery disease, 63% vs 59%; hypertension, 72% vs 75%; chronic obstructive pulmonary disease, 21% vs 26%; and chronic renal insufficiency, 18% vs 18%), mean AAA maximum diameter (6.6 vs 6.4 cm), need for on-the-table conversion to open surgical repair (3% vs 7%), and incidences of nonfatal complications (43% vs 38%) and secondary interventions (23% vs 25%). Preoperative computed tomography scan was available in significantly fewer Hd-unstable patients (64% vs 100%; P < .05). Compared with Hd-stable patients, the Hd-unstable patients had a significantly higher intraoperative need for aortic occlusion balloon (40% vs 6%; P < .05), mean estimated blood loss (744 vs 363 mL; P < .05), incidence of developing abdominal compartment syndrome (ACS; 29% vs 4%; P < .01), and death (33% vs 18%; P < .05). ACS was a significant predictor of death; death in all r-EVAR with ACS was significantly higher compared with all r-EVAR without ACS (10 of 17 [59%] vs 22 of 119 [18%]; P < .01). CONCLUSIONS: EVAR for r-AAA is feasible in Hd-stable and Hd-unstable patients, with a comparable incidence of conversion to open surgical repair, nonfatal complications, and secondary interventions. Hd-stable patients have reduced mortality at 30 days, whereas Hd-unstable patients require intraoperative aortic occlusion balloon more frequently, and have an increased risk for developing ACS and death.

Endovascular repair of ruptured infrarenal abdominal aortic aneurysm is associated with lower 30-day mortality and better 5-year survival rates than open surgical repair.

OBJECTIVE: Endovascular aneurysm repair (EVAR) decreases 30-day mortality for patients with ruptured abdominal aortic aneurysms (r-AAAs) compared with open surgical repair (OSR). However, which patients benefit or whether there is any long-term survival advantage is uncertain. METHODS: From 2002 to 2011, 283 patients with r-AAA underwent EVAR (n = 120 [42.4%]) or OSR (n = 163 [57.6%]) at Albany Medical Center. All data were collected prospectively. Patients were analyzed on an intention-to-treat basis, and outcomes were evaluated by a logistic regression multivariable model. Kaplan-Meier analysis was used to compare long-term survival. RESULTS: The EVAR patients had a significantly lower 30-day mortality than did the OSR patients (29/120 [24.2%] vs 72/163 [44.2%]; P < .005) and better cumulative 5-year survival (37% vs 26%; P < .005). Men benefited more from EVAR (mortality: 20.9% for EVAR vs 44.3% for OSR; P < .001) than did women (mortality: 32.4% vs 43.9%; P = .39). Age ≥80 years was a significant predictor of death for EVAR (odds ratio [OR], 1.07; P = .003) but not for OSR (OR, 1.04; P = .056). Preexisting hypertension was a significant predictor of survival for both EVAR (OR, 0.17; P < .001) and OSR (OR, 0.48; P = .021). Almost one fourth of EVAR patients (21/91 [23.1%]) required secondary interventions. Survival advantage was maintained for EVAR patients to 5 years. CONCLUSIONS: For r-AAA, EVAR reduces the 30-day mortality and improves long-term survival up to 5 years. However, whereas open survivors require few graft-related interventions, up to 23% of EVAR patients will require reintervention for endoleaks or graft migration. Close follow-up of all EVAR survivors is mandatory.

Treatment options for delayed AAA rupture following endovascular repair.

PURPOSE: Delayed abdominal aortic aneurysm (AAA) rupture is a well recognized complication of endovascular aneurysm repair (EVAR). We wanted to evaluate the frequency, etiology, and outcomes of delayed AAA rupture following EVAR, and identify treatment options that facilitate improved survival. METHODS: From 2002 to 2009, 1768 patients underwent elective and emergent EVAR. At a mean follow-up of 29 months, 27 (1.5%) patients presented with delayed AAA rupture and required repair by either open surgical conversion or endovascular means. All data were prospectively collected in a vascular registry, and outcomes analyzed. RESULTS: Over a mean follow-up of 29 months, the incidence of delayed AAA rupture after elective EVAR was 1.4% (24 of 1615 patients), and after emergent EVAR for ruptured AAA was 2.8% (3 of 106 patients). Of the 27 delayed AAA rupture patients, 20 (74%) were considered "lost to follow-up," and, at presentation, 17 (63%) patients had Type 1 endoleak with stent graft migration, three (11%) had Type 1 endoleak without stent graft migration, five (19%) had Type 2 endoleak, and two (7%) had undetermined etiology for aneurysm rupture. Fifteen (55%) patients underwent open surgical repair via retroperitoneal approach with partial (n = 8; 53%) or complete (n = 7; 47%) stent graft explants and aortoiliac reconstruction, 11 (41%) patients underwent a second EVAR, and one (4%) patient refused treatment and died. Supraceliac aortic clamp was required in three (20%) patients with open surgical conversion, and supraceliac occlusion balloon was required in two (18%) patients with EVAR. There were three (11%) postoperative deaths; two following open surgical conversion and one following EVAR. One additional redo-EVAR patient has undergone successful elective conversion to open surgical repair for persistent type II endoleak and increase in AAA size. CONCLUSIONS: Delayed AAA rupture following EVAR can be successfully managed in most patients by open surgical conversion or secondary EVAR. The approach to each patient should be individualized; complete stent graft explant is not necessary in most patients; a secondary EVAR for delayed AAA rupture with or without an elective conversion to open surgical repair remains a viable option. Vigilant routine follow-up is needed for all patients after EVAR.

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.

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.

Endovascular repair of thoracic aortic traumatic transections is a safe method in patients with complicated injuries.

PURPOSE: Historically thoracic aortic rupture secondary to trauma was treated with cardiopulmonary bypass and open surgery. With the advent of endovascular grafting, physicians have the ability to reconstruct the thoracic aortic transection using a less invasive technique. In this study, we examine our experience with stent graft repair of thoracic transections secondary to trauma. METHODS: The medical records of patients treated at a level I trauma center from 2005 to 2008 were reviewed. Those patients who had an aortic transection treated with an endograft were identified and evaluated for in-hospital mortality and morbidity and concurrent injuries. Demographics, procedural details, and outcomes were analyzed. RESULTS: Over a 3-year period, 18 thoracic aortic transections secondary to trauma were identified in patients with a mean age of 43 (range, 16-80). Primary technical success was 100%. None of the patients required explant or open repair during this time period. In-hospital mortality was 2 of 18 (11%); all patients had multiple trauma including long bone fractures. The subclavian artery origin was covered by the stent graft in 9 of the 18 patients. The mean estimated blood loss per procedure was 222 cc. No patient in this series had postoperative paraplegia. Follow-up ranged from 1 to 50 months with an average of 13 months. There have been no late explantation or device failures identified. CONCLUSION: Endovascular repair of traumatic thoracic aortic transections can be performed safely with a relatively low mortality and morbidity and should be the procedure of choice for patients presenting with traumatic thoracic aortic ruptures.

Ruptured abdominal aortic aneurysm: endovascular program development and results.

Improvements in endovascular technology and techniques have allowed us to treat patients in ways we never thought possible. Today endovascular treatment of ruptured abdominal aortic aneurysms is associated with markedly decreased morbidity and mortality when compared to the open surgical approach, yet there are several fundamental obstacles in our ability to offer these endovascular techniques to most patients with ruptured aneurysms. This article will focus on the technical aspects of endovascular aneurysm repair for rupture, with particular attention to developing a standardized multidisciplinary approach that will help ones ability to deal with not just the technical aspects of these procedures, but also address some of the challenges including: the availability of preoperative CT, the choice of anesthesia, percutaneous vs. femoral cut-down approach, use of aortic occlusion balloons, need for bifurcated vs. aorto-uniiliac stentgrafts, need for adjunctive procedures, diagnosis and treatment of abdominal compartment syndrome, and conversion to open surgical repair.

Comparative results of open lower extremity revascularization in nonagenarians.

INTRODUCTION: The average lifespan in the United States continues to lengthen. We have observed a similar trend in our patients, with an increased number of nonagenarians presenting for evaluation of vascular disease. This study evaluated outcomes of lower extremity revascularization in patients aged >or=90 years. METHODS: The vascular registry at Albany Medical College was retrospectively reviewed for all lower extremity bypasses performed between 1996 and 2006. We evaluated patient demographics, indications, procedure, patency rates, and complications. Patients were divided into groups based on age >or=90 years (>or=90 group) and <90 years (<90 group). Variables were evaluated by chi(2) analysis. Outcomes were prepared using life-table methods and compared with log-rank analysis. RESULTS: During the last 10 years, 5443 lower extremity bypasses were performed on patients aged <90 years and 150 on patients aged >or=90 years. The <90 group had significantly more men (61.4% vs 29.3%) and was obviously younger, at 68 years (range 7-89 years) vs 92 years (range, 90-101 years). The <90 group had more comorbidities in terms of diabetes, active tobacco use, and hypercholesterolemia. No significant difference was noted in coronary artery disease or chronic renal insufficiency between the groups. Critical limb ischemia as an indication was significantly higher in the >or=90 group (149 [99%] vs 4472 [82%]; P < .0.5). Strikingly, the primary patency was significantly higher in the >or=90 group at 4 years (77% vs 62%; P < .05). Complication and amputation rates did not differ between the groups. Perioperative (15% vs 3%; P < .05) and 1-year (45% vs 11%; P < .05) mortality rates were significantly higher in the >or=90 group. CONCLUSION: Lower extremity bypass for nonagenarians offers acceptable patency and limb salvage but at a significantly higher mortality rate.

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.

Establishing a protocol for endovascular treatment of ruptured abdominal aortic aneurysms: outcomes of a prospective analysis.

PURPOSE: In our transition from elective abdominal aortic aneurysm (AAA) to emergent ruptured AAA (r-AAA) repair with endovascular techniques, we recognized that the availability of endovascularly trained staff in the operating rooms and emergency departments, and adequate equipment were the limiting factors. To this end, we established a multidisciplinary protocol that facilitates endovascular repair (EVAR) of r-AAA. METHODS: In January 2002, we instituted a multidisciplinary approach that included the vascular surgeons, emergency department physicians, anesthesiologists, operating room staff, radiology technicians, and availability of a variety of stent-grafts to expedite EVAR of r-AAAs. Five patients with symptomatic, not ruptured AAAs suitable for EVAR underwent simulation of patients presenting to the emergency department with r-AAAs. Emergency department physicians alerted the on-call vascular surgery team (vascular surgeon, vascular resident or fellow) and the operating room staff, emergently performed an abdominal computed tomography (CT) scan in only hemodynamically stable patients with systolic blood pressures > or =80 mm Hg, and transported the patient to the operating room. The vascular surgeon informed the operating room staff to set up for EVAR and open surgical repair in an operating room equipped with interventional capabilities. The operating room setup was rehearsed with the anesthesiologists, operating room staff, and radiology technicians who were knowledgeable of the sequence of steps involved. Since then, 40 patients have undergone emergent EVAR for r-AAAs with general anesthesia. RESULTS: No complications developed in any of the symptomatic (simulation) patients, and 40 (95%) of 42 patients with r-AAAs had a successful EVAR with Excluder (n = 27, 68%), AneuRx (n = 9, 23%), or the Zenith (n = 4, 10%) stent-grafts. The mean age was 73 years (range, 54 to 88 years), and pre-existing comorbidities included coronary artery disease in 26 (65%), hypertension in 23 (58%), chronic obstructive pulmonary disease in 7 (18%), renal insufficiency not on dialysis in two (5%), and diabetes in nine (23%). Fourteen (38%) patients were diagnosed with r-AAAs at another hospital and subsequently were transferred to us, and 26 (62%) presented directly to the emergency department at our institution. At the initial presentation, 30 patients (75%) were hemodynamically stable and either had a CT scan at an outside hospital or in the emergency department, and 10 (25%) hemodynamically unstable patients with systolic blood pressures <80 mm Hg were rushed to the operating room for EVAR without a preoperative CT scan. The mean time from the presumptive diagnosis of a r-AAA in the emergency department to the operating room for EVAR was 20 minutes (range, 10 to 35 minutes), and the mean operative time from skin incision to closure was 80 minutes (range, 35 to 125 minutes). Seven patients (18%) needed supraceliac aortic occlusion balloon, and six (15%) needed aortouniiliac stent-grafts. The mean blood loss was 455 mL (range, 115 to 1100 mL). Two patients each (5%) developed myocardial infarction, renal failure, and ischemic colitis, seven (18%) developed abdominal compartment syndrome, and seven (18%) died. Over a mean follow-up of 17 months, three patients with endovascular r-AAA repair required four secondary procedures. CONCLUSIONS: The early results show that emergent endovascular treatment of hemodynamically stable and unstable patients is associated with a limited mortality of 18% once a standardized protocol is established. There is an increased recognition of emerging complications with an endovascular approach, and a synchrony of disciplines must be developed to initiate a successful program for endovascular treatment of r-AAAs.

Hemodynamic changes associated with bypass stenosis regression.

OBJECTIVE: Ultrasound scanning is used to detect velocity increases indicative of a bypass stenosis. Subsequent examinations have shown regression of some stenotic lesions. This study examined hemodynamic changes that coincided with stenosis regression. METHODS: Duplex ultrasound scans were used to record the peak systolic velocity (PSV) and volume flow from proximal and distal segments of infrainguinal bypasses. Valve remnants or other image defects were also noted. The PSV ratio (Vr) was calculated as the PSV at a stenosis divided by the PSV proximal to the lesion. A stenosis was defined as Vr >/=2.0. RESULTS: An initial ultrasound scan performed 31 +/- 6 days after surgery revealed a stenosis in 68 of 565 bypasses. In six bypasses, the increased PSV (272 +/- 61 cm/s) and Vr (3.4 +/- 1.3) were sustained during the follow-up period of 8 +/- 3 months. In 27 bypasses with a PSV of 335 +/- 63 cm/s and a Vr of 4.0 +/- 1.6, the stenosis was repaired. In 35 bypasses with a PSV of 261 +/- 82 cm/s and Vr of 3.2 +/- 1.2, stenosis regression occurred with no increases in PSV observed on later scans. In this group, proximal bypass flow decreased during the follow-up interval from 247 +/- 130 mL/min to 151 +/- 135 mL/min and distal flow from 180 +/- 102 mL/min to 103 +/- 54 mL/min ( P < .05, paired t test). Ultrasound image abnormalities were noted in 4 bypasses (67%) with persistent stenoses, 14 with repaired stenoses (52%), and 10 with resolved stenoses (29%). CONCLUSION: These data indicate early postoperative hyperemia is present in bypasses, demonstrating focal velocity increases. Such velocity increases may be the result of the bypass conduit acting as a flow-limiting lesion until the hyperemia subsides. As the blood flow decreases so does the PSV, giving the appearance of stenosis regression.