Hypercoagulability in Patients With Coronavirus Disease (COVID-19): Identification of Arterial and Venous Thromboembolism in the Abdomen, Pelvis, and Lower Extremities.

The purpose of this article is to describe arterial and venous thromboembolism in the abdomen, pelvis, and lower extremities in patients with coronavirus disease (COVID-19). Eighty-two patients with COVID-19 who underwent abdominal ultrasound or CT were retrospectively compared with 82 patients without COVID-19 for thromboembolism and solid-organ infarction. Nine (11%) patients with COVID-19 had thromboembolic findings, with medium to large arterial thrombi in five. One patient without COVID-19 had known portal vein thrombus on CT. Thromboembolic findings occurred more frequently in patients with than without COVID-19 (p = 0.02).

Intimomedial mucoid degeneration of the peripheral arteries.

Intimomedial mucoid degeneration, a rare vascular disorder characterized by mucinous deposition in the intima and media layers, causes aneurysmal degeneration of the vessel wall in young patients. Because of the potential for involvement of multiple vessels, these patients may require full body imaging and long-term follow-up. We describe three patients with intimomedial mucoid degeneration and variable clinical presentations. One patient presented emergently with a spontaneously ruptured nonaneurysmal subclavian artery; one patient presented with a known posterior tibial artery aneurysm and new onset of focal pain and paresthesias over the aneurysm; and one patient presented with a self-discovered dorsalis pedis artery aneurysm.

Prophylactic inferior vena cava filters prevent pulmonary embolisms in high-risk patients undergoing major spinal surgery.

STUDY DESIGN: Clinical case series. OBJECTIVE: To show the efficacy of prophylactic inferior vena cava (IVC) filters in preventing venous thromboembolic event (VTE) in high-risk patients undergoing major spinal surgery. SUMMARY OF BACKGROUND DATA: Patients undergoing major spinal surgery are at increased risk for VTEs. Recent studies have shown IVC filters are effective in preventing clinically significant pulmonary embolism (PE), but have not documented the frequency of all emboli prevented. METHODS: Patients undergoing major spinal surgery from 2006 to 2009, having IVC filters placed for VTE prophylaxis, were reviewed. Patients with 2 or more risk factors for VTE were included and their perioperative courses were reviewed for PE and device-related complications. Cavograms obtained at the time of attempted filter retrieval identified intercepted emboli. The rates of intercepted emboli and clinical PEs were compared with those of similar populations undergoing similar procedures. RESULTS: Approximately 17% of patients had entrapped thrombus present at attempted filter retrieval. An additional 17% of filters were unable to be retrieved due to change in position within the IVC. No patients experienced symptomatic PE. One patient developed a deep vein thrombus requiring pharmacologic treatment and another patient developed superficial phlebitis. There were no complications related to IVC filter use. CONCLUSIONS: These findings show that the decreased rate of PE observed in this and other series is likely because of the use of IVC filters, rather than sampling bias inherent when studying a relatively rare problem. The safety of IVC filters in this population is also confirmed. The observed rate of clinical PE is consistent with other published series. Emboli intercepted by filters may more accurately estimate clinically significant emboli prevented. Therefore, cavograms may prove to be a valuable method of assessing the efficacy of these devices in future studies.

Femoral-popliteal bypass with endoscopically harvested saphenous vein in patients with TASC D disease of the superficial femoral artery.

BACKGROUND: This study evaluated patients undergoing femoropopliteal bypasses using endoscopically harvested vein to treat Trans-Atlantic Inter-Society Consensus (TASC) stage D lesions. Primary patency and primary assisted patency were evaluated, as were perioperative morbidity and mortality and hospital length of stay (LOS). Results for this minimally invasive alternative to femoropopliteal bypass with conventional open vein harvesting were analyzed. METHODS: A retrospective analysis was performed on patients who underwent femoral-popliteal bypass with endoscopic saphenous vein harvest and angiographic TASC D anatomy. Postoperative duplex exams were evaluated, and the study end points of graft thrombosis or the development of a high-grade stenosis prompting reintervention were sought. Patient demographics, morbidity, mortality, and hospital LOS were analyzed. RESULTS: Twenty-seven patients meeting our inclusion criteria underwent surgery between June 2002 and June 2007. Indications for surgery in these patients were claudication (n=10), gangrene or ulceration (n=9), and ischemic rest pain (n=8). Fifty-two percent of the patients were male, 50% had cardiac disease, 65% had hypertension, 54% were diabetic, and 65% had a significant smoking history. Median LOS was 2.5 days in claudicants, 3.0 days in patients with rest pain, and 7.0 days in patients with gangrene or ulceration (p<0.05). Kaplan-Meier primary patency and primary assisted patency rates were 73.2% and 80.8% at 1 year, respectively; and these rates were maintained for 70 months. The only perioperative complication was a superficial wound infection, and two patients died during follow-up from causes unrelated to the surgery. CONCLUSION: Femoropopliteal bypass using endoscopic vein harvest is a durable reconstructive vascular procedure which can be performed with minimal postoperative morbidity, short LOS, and satisfactory long-term patency.

Surgical management of mesenteric occlusive disease: a contemporary review of invasive and minimally invasive techniques.

Mesenteric ischemia (MI) is caused by compromised blood flow to the arteries supplying the small and large intestine. Acute occlusive mesenteric ischemia (AMI) presents with the abrupt onset of severe abdominal pain, which if not diagnosed and treated immediately can cause bowel necrosis and prove fatal. Chronic occlusive mesenteric ischemia (CMI) is usually a longstanding process characterized by postprandial abdominal pain, progressive food intolerance, and weight loss. If untreated, CMI can lead to progressive disability and failure to thrive. This review article highlights the clinical and radiologic diagnosis of acute mesenteric ischemia and CMI and compares their treatment with surgical revascularization and the less invasive alternative of mesenteric artery angioplasty and stenting.

A contemporary review of popliteal artery aneurysms.

Popliteal artery aneurysms account for 85% of all peripheral aneurysms and are frequently associated with abdominal aortic aneurysms. Up to 75% of all popliteal artery aneurysms are discovered in symptomatic patients who present with arterial insufficiency, leg swelling, or pain. Popliteal artery aneurysms can be diagnosed with duplex ultrasonography. Aneurysm repair should be considered for all symptomatic patients with rest pain or limb-threatening symptoms. Asymptomatic aneurysms larger than 2 cm should also be treated to prevent the development of limb-threatening ischemia and assure better surgical bypass graft patency and longer freedom from amputation. Conventional aneurysm repair consists of either opening the aneurysm sac and interposing a bypass graft or aneurysm ligation combined with bypass grafting. If the aneurysm sac is left intact, side branch perfusion may persist and the aneurysm may continue to enlarge and can rupture. Endovascular popliteal aneurysm repair has not demonstrated clinical equipoise to standard surgery but may be advantageous in select high-risk patients.

Fate of collateral vessels following subintimal angioplasty.

PURPOSE: To evaluate the fate of collateral vessels adjacent to and within the target lesion following subintimal angioplasty (SIA). METHODS: Pre and postprocedural angiograms were reviewed for 29 patients undergoing SIA of the lower extremity arteries over a 3-year period. The number of patent collateral vessels

Predicting aneurysm enlargement in patients with persistent type II endoleaks.

OBJECTIVE: The clinical significance of type II endoleaks is not well understood. Some evidence, however, indicates that some type II endoleaks might result in aneurysm enlargement and rupture. To identify factors that might contribute to aneurysm expansion, we analyzed the influence of several variables on aneurysm growth in patients with persistent type II endoleaks after endovascular aortic aneurysm repair (EVAR). METHODS: In a series of 348 EVARs performed during a 10-year period, 32 patients (9.2%) developed type II endoleaks that persisted for more than 6 months. Variables analyzed included those defined by the reporting standards for EVAR (SVS/AAVS) as well as other endoleak characteristics. Univariate, receiver operating characteristic curve, and Cox regression analyses were used to determine the association between variables and aneurysm enlargement. RESULTS: The median follow-up period was 26.5 months (range, 6-88 months). Thirteen patients (41%) had aneurysm enlargement by 5 mm or more (median increase in diameter, 10 mm), whereas 19 (59%) had stable or shrinking aneurysm diameter. Univariate and Cox regression analyses identified the maximum diameter of the endoleak cavity, ie, the size of the nidus as defined on contrast computed tomography scan, as a significant predictor for aneurysm enlargement (relative risk, 1.12; 95% confidence interval, 1.04-1.19; P =.001). The median size of the nidus was 23 mm (range, 13-40 mm) in patients with aneurysm enlargement and 8 mm (range, 5-25 mm) in those without expansion (Mann-Whitney U test, P <.001). Moreover, receiver operating characteristic curve and Cox regression analyses showed that a maximum nidus diameter greater than 15 mm was particularly associated with an increased risk of aneurysm enlargement (relative risk, 11.1; 95% confidence interval, 1.4-85.8; P =.02). Other risk factors including gender, smoking history, hypertension, need of anticoagulation, aneurysm diameter, type of endograft used, and number or type of collateral vessels were not significant predictors of aneurysm enlargement. CONCLUSIONS: In patients with persistent type II endoleaks after EVAR, the maximum diameter of the endoleak cavity or nidus is an important predictor of aneurysm growth and might indicate the need for more aggressive surveillance as well as earlier treatment.

System to decrease length of stay for vascular surgery.

OBJECTIVES: Reduction of length of stay (LOS) is critical for optimal use of hospital resources. We developed and evaluated a system to aggressively reduce LOS for vascular surgery. METHOD: Key to this system, which we introduced on January 1, 2001, was appointment of a LOS officer, who communicated daily during hospitalization with patients and families about discharge planning, organized outpatient services for wound care and rehabilitation to transition patients quickly to nonhospital care, and had biweekly meetings with relevant paramedical services. LOS for 509 patients operated on in 2000 (standard group) was compared with LOS for 474 operated on in 2001 and 595 patients operated on in 2002 (LOS reduction groups). Data for all patients with aortic aneurysm, carotid artery stenosis, lower extremity critical ischemia or amputation, and foot debridement were included. RESULTS: LOS in 2000 averaged 8.5 days, compared with 5.9 days in 2001 and 5.6 days in 2002. All decreases in LOS for each diagnostic category in 2001 and 2002 were statistically significant (P = <.001-.03). There was no significant increase in readmission rate (2.2% vs 1.9% and 2.0%, respectively), mortality rate (0.8% vs 0.6% and 0.7%, respectively), or percent of patients who received endovascular treatment (18% vs 16% and 14%, respectively). These decreases in LOS saved the hospital more than US dollars 616200 in 2001, and US dollars 847550 in 2002 (US dollars 500/patient-day). CONCLUSIONS: A committed LOS officer with major specific daily responsibilities for decreasing LOS and discharging patients resulted in a 31% to 33% decrease in LOS, with important cost savings to the hospital and no negative effect on patient care.

Digital fluoroscopy as a valuable adjunct to open vascular operations.

The increasing availability of and vascular surgeons' familiarity with digital cine-fluoroscopy in the operating room has been facilitated by the advent and growing popularity of endovascular aortoiliac aneurysm repair and other endovascular techniques that are being incorporated into vascular surgical practice. Digital cine-fluoroscopy can also be used as a valuable adjunct to standard open vascular procedures in several ways including: performance of completion angiography, fluoroscopically-assisted thromboembolectomy, intraoperative planning angiography, fluoroscopically-guided pressure gradient measurements, achieving vascular control of proximal arteries, intraoperative thrombolysis of compromised outflow tracts, and angioplasty and stenting of lesions detected intraoperatively. These techniques can improve the outcome of standard vascular procedures by permitting the identification of inflow, outflow, conduit, and anastomotic defects intraoperatively and guiding their repair. Additionally, in many cases they can reduce the amount of exposure required, reduce intraoperative blood loss, and minimize trauma to vessels during thrombectomy. Fluoroscopic guidance can facilitate and improve these and other aspects of standard open vascular procedures. Conversely, the ability to perform open interventions can facilitate the performance of many endovascular interventions. It is becoming increasingly important to be facile with both open and E fluoroscopically guided techniques in order to fully treat the spectrum of vascular disease in an optimum fashion.

Delayed open conversion following endovascular aortoiliac aneurysm repair: partial (or complete) endograft preservation as a useful adjunct.

OBJECTIVES: The purpose of this study was to review our experience with delayed open conversion (>30 days) following endovascular aortoiliac aneurysm repair (EVAR) and to introduce the concept and advantages of endograft retention in this setting. METHODS: From January 1992 to January 2003, a total of 386 EVARs using a variety of endografts were successfully deployed. Eleven (2.8%) patients required delayed conversion to open repair at an average of 30 months (range, 10-64). Data from all patients undergoing both EVAR and open conversion were prospectively collected. RESULTS: EVARs were performed using grafts made by Talent (4), Vanguard (2,) AneuRx (1), and Surgeon (4). Conversion to open repair (9 transabdominal, 1 retroperitoneal, 1 transabdominal plus thoracotomy) was performed for aneurysm rupture in 7 patients (4 type 1 endoleak, 2 type 2 endoleak, 1 aortoenteric fistula) and aneurysm enlargement in 4 patients (1 type 1 endoleak, 1 type 2 endoleak, 1 type 3 endoleak, 1 endotension). Patients with aneurysm rupture were treated on an emergent basis. Complete removal of the endograft with supraceliac cross-clamping was performed in two cases. One patient (rupture) did not survive the operation, and one patient (aortoenteric fistula) died 2 weeks postoperatively. In the remaining nine cases, the endograft was either completely (1) or partially (6) removed, or left in situ (2). Supraceliac balloon control (2), supraceliac clamping (1), suprarenal clamping (1), or infrarenal clamping (5) was used in these cases. All nine of these patients survived the operation. In one procedure in which the endograft was left intact (endotension), repair was accomplished by exposing the endograft and by placing a standard tube graft over it as a sleeve. In the second procedure in which the graft was left in situ (rupture), the graft was well incorporated, and bleeding lumbar arteries were oversewn and the sac was closed tightly over the endograft. In the remaining 7 cases, the endograft was transected and the proximal portion only (6) or the proximal and distal portions (1) were excised. All surviving patients continue to do well and remain without complications associated with the endograft remnant at a mean follow-up of 22 months (range, 3-56) from the time of open conversion and 46 months (range, 10-73) from the time of original EVAR. CONCLUSIONS: Open repair in the setting of a long-standing endograft offers several unique technical challenges but can be successfully accomplished in most patients. Preservation of all or part of the endograft is possible in many patients. This technique simplifies the operative approach and is preferred over complete endograft removal if possible.

Does transrenal fixation of aortic endografts impair renal function?

OBJECTIVES: Transrenal fixation (TFX) of aortic endografts is thought to increase the risk for renal infarction and impaired renal function. We studied the late effects of TFX on renal function and perfusion. METHODS: Of 189 patients with commercial aortic endografts, which we inserted between 1995 and 2002, we reviewed data for 130 patients (112 men, 18 women) with available creatinine (Cr) concentration and contrast enhanced computed tomography (CT) scans preoperatively and 1 to 97 months after the procedure. Of the 130 patients, 69 patients had TFX and 61 patients had infrarenal fixation (IFX). Both groups were physiologically comparable. Average age was 76 +/- 8 years for patients with TFX and 75 +/- 8 years for patients with IFX. Presence of renal infarct or renal artery occlusion was determined by nephrograms on serial contrast-enhanced CT scans. RESULTS: Mean follow-up was 17 +/- 16 months (range, 1-54 months) for TFX and 21 +/- 21 months (range, 1-97 months) for IFX. Mean serum Cr concentration increased significantly during long-term follow-up in both groups (TFX, 1.3 +/- 0.5 mg/dL to 1.5 +/- 0.8 mg/dL, P <.01; IFX, 1.3 +/- 0.7 mg/dL to 1.4 +/- 0.8 mg/dL, P <.03). Creatinine clearance (CrCl) similarly decreased over long-term follow-up in both groups (TFX, 53.3 +/- 17.7 mL/min/1.73 m(2) to 47.9 +/- 16.2 mL/min/1.73 m(2), P <.01; IFX, 58.1 +/- 22.7 mL/min/1.73 m(2) to 53.1 +/- 23.4 mL/min/1.73 m(2), P <.02). There were no significant differences in the increase in Cr concentration (P =.19) or decrease in CrCl (P =.68) between TFX and IFX groups. Small renal infarcts were noted in four patients (5.8%) in the TFX group and one patient (1.6%) in the IFX group. No increase in Cr concentration or decrease in CrCl was noted in any patient with a renal infarct. Postoperative renal dysfunction developed in 7 of 69 patients (10.1%) in the TFX group and 7 of 61 patients (11.5%) in the IFX group. There were no statistically significant differences between groups with respect to number of patients with new renal infarcts (P =.37) or postoperative renal dysfunction (P =.81). CONCLUSION: There is a slight increase in serum Cr concentration and decrease in CrCl after aortic endografting. However, there was no significant difference in these changes between patients with TFX and IFX. Although TFX may produce a higher incidence of small renal infarcts, these do not impair renal function. Thus our midterm results suggest that TFX can be performed safely, with no greater change in renal function than observed after IFX.

Open aneurysm repair at an endovascular center: value of a modified retroperitoneal approach in patients at high risk with difficult aneurysms.

OBJECTIVE: This study was undertaken to evaluate elective open abdominal aortic aneurysm (AAA) repair and the role of a modified retroperitoneal approach in a high-volume endovascular center. METHODS: We reviewed prospectively collected data for 175 elective infrarenal open AAA repairs performed over 6 years. A transperitoneal approach was used in 118 procedures, and a modified retroperitoneal approach was used in 57 procedures. The incisional modification, which facilitated repair in patients with massive obesity, scarring, or ventral hernia, included a higher, more posterolateral location in the ninth intercostal space. Risk factors that added to the difficulty of the repair included aneurysms with a short (<1 cm) or no aortic neck in 45 patients; large, angled or flared aortic neck in 32 patients;, tortuous and calcified iliac arteries in 6 patients; morbid obesity in 10 patients; low ejection fraction (15%-30%) in 14 patients; chronic obstructive pulmonary disease, with forced expiratory volume at 1 second less than 55% in 4 patients; previous laparotomy in 18 patients; previous left-sided colectomy in 11 patients; large right iliac aneurysm in 8 patients; large ventral hernia in 8 patients; pelvic irradiation in 4 patients; failed endovascular repair in 5 patients; and previous failed open repair attempt in 2 patients. Many of these factors occurred with significantly greater frequency (P =.04-.001) in the retroperitoneal group. All factors were correlated with outcome. RESULTS: Despite these risk factors, overall 30-day mortality was 3.5% (retroperitoneal group, 3.8%), and mean length of hospital stay was 9 days (retroperitoneal group, 8 days). There was no significant correlation between mortality or length of stay and any of the mentioned risk factors (P >.2). CONCLUSION: In the era of endovascular aneurysm exclusion, open AAA repair is generally used to treat anatomically complex or difficult aneurysms, many of which are present in patients at high risk. Despite this combination of anatomic and systemic risk factors, the modified retroperitoneal approach facilitates treatment in difficult circumstances and enables open AAA repair to be performed with acceptable mortality and morbidity.

Does subintimal angioplasty have a role in the treatment of severe lower extremity ischemia?

OBJECTIVE: Subintimal angioplasty (SIA) has been advocated to treat long segment lower extremity arterial occlusions, but many question its value. We evaluated the role of SIA in a group of patients with severe lower extremity arterial occlusive disease. METHODS: During a 2.5-year period, 39 patients with arterial occlusions (median length, 8 cm; range, 2 to 31 cm) were treated on an intention-to-treat basis with SIA. Twenty-five patients had gangrene, five had rest pain, and nine had disabling (

Patency rates of femorofemoral bypasses associated with endovascular aneurysm repair surpass those performed for occlusive disease.

PURPOSE: To evaluate the patency rates of femorofemoral grafts performed in conjunction with aortomonoiliac or aortomonofemoral (AMI/F) endografts. METHODS: Over the past 8 years, 110 patients (98 men; mean age 77+/-7 years, range 57-90) underwent aortoiliac aneurysm repair with an AMI/F endograft. Follow-up data in these patients were prospectively collected for a mean 2.3 years (range 1-68 months). RESULTS: There were 2 early (<7 days) AMI/F endograft thromboses with secondary femorofemoral graft occlusion. In both patients, patency of all grafts was restored by thrombectomy plus stenting of the endograft. Three late (4, 5, and 10 months) AMI/F endograft thromboses led to femorofemoral graft failure; 2 were successfully treated, but the third patient refused further intervention. No femorofemoral bypass failed in the absence of AMI/F endograft thrombosis. There were no femorofemoral graft infections. Four-year life-table primary and secondary patency rates were 95% and 99%, respectively. CONCLUSIONS: Femorofemoral bypasses with AMI/F endografts for aneurysmal disease are durable procedures and have better patency than femorofemoral grafts used to treat occlusive disease. Femorofemoral bypass patency rates alone are not a disadvantage of aortomonoiliac endografts.

Spontaneous recanalization of arterial occlusions: an unusual mechanism for symptomatic improvement.

OBJECTIVE: Patients with infrainguinal occlusive disease may experience spontaneous symptomatic improvement. This is generally thought to be from augmented collateral circulation. This study reports another mechanism. METHODS: Over a 20-year period, 4123 patients underwent lower extremity arteriography for limb ischemia. For a variety of reasons, 451 patients had repeat arteriography. RESULTS: Five patients were identified as having conclusive arteriographic evidence of spontaneous recanalization of occluded arterial segments without having undergone any surgical or thrombolytic interventions. Repeat contrast arteriography was performed on these patients for failing grafts (n = 2) or contralateral lower extremity ischemia (n = 3). Three other patients had magnetic resonance arteriographic or duplex arteriographic evidence of spontaneous arterial recanalization. Spontaneous recanalizaton occurred in ileofemoral (n = 2), superficial femoral (n = 2), popliteal (n = 3), and peroneal (n = 1) arterial segments. The average time interval of occlusion to recanalization was 21 weeks (2 weeks to 2 years). Two of the eight patients had failed revascularization procedures before spontaneous recanalization. All eight patients had restoration of pulses distal to the recanalized segments and significant symptomatic improvement as defined with the Society for Vascular Surgery/American Association for Vascular Surgery categories for limb ischemia. CONCLUSION: Spontaneous recanalization of arterial segments can occur and must be considered when evaluating other proposed treatments of critical limb ischemia, including cilostazol, lytic agents, and angiogenic agents, such as vascular endothelial growth factor. Although its true incidence is unknown, this represents another mechanism for spontaneous symptomatic improvement without treatment in patients with severe limb ischemia.

Nonoperative management with selective delayed surgery for large abdominal aortic aneurysms in patients at high risk.

OBJECTIVE: An accepted fact is that abdominal aortic aneurysms (AAAs) larger than 5.5 cm should undergo elective repair. However, subsets of these patients have serious comorbid conditions, which greatly increase operative risk. This study evaluated the outcomes of periods of protracted nonoperative observational management with selective delayed surgery in patients at high risk with large infrarenal and pararenal AAAs. METHODS: Among 226 patients with AAAs more than 5.5 cm, we selected 72 with AAAs from 5.6 to 12.0 cm (mean, 7.0 cm) for periods of nonoperative management because of their prohibitive surgical risks. Comorbid factors included a low ejection fraction of 15% to 34% (mean, 22%) in 18 patients, 1 second forced expiratory volume less than 50% (mean, 38%) in 25, prior laparotomy in 10, and morbid obesity in 22. Follow-up examination was complete in the 72 patients for the 6 to 76 months (mean, 23 months) that they underwent nonoperative treatment. Fifty-three patients ultimately underwent operation because of AAA enlargement or onset of symptoms after 6 to 72 months (mean, 19 months) of nonoperative treatment. RESULTS: Of the 72 selected patients, 54 (75%) are living and 18 (25%) are dead. Seven patients who underwent only nonoperative treatment presently survive after 28 to 76 months (mean, 48 months). Of the 18 deaths, AAA rupture occurred in only three patients (4%) who were observed for 12, 31, and 72 months before rupture. Nine other deaths (13%) occurred after 6 to 72 months from comorbidities unrelated to the AAA. Six of the 53 patients who underwent delayed operation died within 30 days of operation (11% mortality rate). The mortality rate for the 154 good-risk patients with an AAA who underwent prompt open or endovascular repair was 2.2%. CONCLUSION: These data indicate that some patients with large AAAs and serious comorbidities are acceptably managed for long periods (6 to 76 months) with nonoperative means. Substantial delays of 12 to 76 months resulted in an AAA rupture rate of only 4%, and 13% of these patients (nine of 72) died of comorbidities unrelated to AAA rupture or surgery. Mortality rate in this group of patients, when operated, was 11% (six of 53). These findings support the selective use of nonoperative management in some patients with large AAAs and serious comorbidities.