Structural implications of fenestrated stent graft misalignment.

BACKGROUND: Endovascular aneurysm repair is a minimally-invasive method for the treatment of abdominal aortic aneurysms. For aneurysms that involve the visceral arteries, a custom-made stent graft with fenestrations for the branch arteries is required. The purpose of the current study is to evaluate the structural impact of misaligned fenestrations with respect to luminal patency and proximal aortic neck apposition in an in vitro model. METHODS: A custom apparatus was used to evaluate seven Anaconda and three Zenith fenestrated stent grafts. All stent grafts were evaluated at 10° increments of stent/fenestration misalignment up to 80°. Images were captured at each interval and the luminal cross-sectional area and wall apposition were measured. RESULTS: The Anaconda stent graft, which has an unsupported main body, demonstrated a linear reduction in luminal patency at increasing angles of misalignment (P < 0.0001). Stent/fenestration misalignments of 20° and 80° resulted in decreases in mean luminal patency of 14% and 54% respectively. The Zenith stent graft demonstrated a similar decrease in luminal patency, starting at misalignments of ≥40° (P < 0.0001). However, with stent/fenestration misalignments of ≥30°, apposition between the Zenith stent graft and the simulated aortic neck was compromised suggesting the creation of a type Ia endoleak. CONCLUSIONS: Both the Anaconda and Zenith devices behave adversely at extreme angles of misalignment with luminal narrowing in the Anaconda device and loss of wall apposition in the Zenith device; however, both stent grafts appear to be equivalent at low angles of misalignment.

The Impact of Compliance with Imaging Follow-up on Mortality After Endovascular Abdominal Aortic Aneurysm Repair: A Population Based Cohort Study.

OBJECTIVE: Compliance with regular imaging follow-up after endovascular aortic aneurysm repair (EVAR) is inconsistent, and evidence of benefit from scheduled long-term surveillance is limited. This study sought to characterize the association between post-EVAR imaging frequency and long-term survival. METHODS: Using administrative health databases for the province of Ontario, Canada, a cohort of patients was identified who underwent EVAR between 2004 and 2014. Minimum appropriate imaging follow-up (MAIFU) was defined as a CT scan or ultrasound of the abdomen within 90 days of EVAR as well as every 15 months thereafter. Multivariate time to event analyses characterized the association between compliance with MAIFU over time and all-cause mortality. RESULTS: 4988 patients treated by EVAR were identified. Median follow-up was 3.4 years (IQR 2.0-5.3 years) and 90 day mortality was 1.6%. Among those who survived over 90 days, 87% (N = 4251 of 4902) underwent at least one CT scan or ultrasound of the abdomen within 90 days, but only 58% (N = 2859 of 4902) went on to meet MAIFU criteria. Infrequent imaging correlated with lower follow-up by a vascular surgeon, but not with infrequent primary care or specialist consultations. Consistently meeting MAIFU criteria was associated with a lower risk of death when compared with missing the first imaging follow-up within 90 days (HR 0.82, 95% CI 0.69-0.96, p = .014), or when compared with having first imaging follow-up within 90 days but subsequently not meeting MAIFU criteria (HR 0.78, 95% CI 0.68-0.91, p = .001). A larger proportion of the follow-up period meeting MAIFU criteria was associated with a lower risk of death. CONCLUSIONS: These data support efforts to improve compliance with imaging surveillance after EVAR.

Using a multimedia presentation to improve patient understanding and satisfaction with informed consent for minimally invasive vascular procedures.

OBJECTIVE: As vascular procedures become more complex, patient understanding of their treatment(s) can become more difficult. We wished to evaluate the utility of multimedia presentations (MPs) to improve patient understanding of their vascular interventions. METHODS: Patients undergoing endovascular aneurysm repair (EVAR), peripheral angioplasty, Hickman catheter and peripherally inserted central catheter (PICC) insertion were randomized into a control group receiving traditional verbal consent, and a MP group that were shown a two minute simplified video of their procedure on an iPad™ computer in addition to the traditional verbal consent. After obtaining consent, all patients completed a questionnaire assessing their comprehension of the procedure, and satisfaction with the consent process. Satisfaction was rated on a 5 point Likert scale with 5 being 'very helpful' in understanding the procedure. RESULTS: Ninety-three patients were recruited for this study, 62% of which were male. The intervention significantly increased total comprehension in all procedure types controlling for procedure type (multimedia vs. control; F = 9.14, P = .003). A second ANOVA showed there was a significant main effect by intervention (F = 44.06, p < .000) with those in the intervention group showing higher overall satisfaction scores after controlling for surgery type. CONCLUSION: This study suggests that patients find the use of MP during the consent process to be helpful in patient understanding and that there is improved satisfaction. Given the rapid rate of innovation in vascular interventions, increased regular use of MPs to help patients understand their procedures would be beneficial in the care of patients undergoing vascular interventions.

Aneurysmal degeneration of vein conduit used for vascular reconstruction-Case report and literature review.

INTRODUCTION: Popliteal artery aneurysms (PAA) are the most prevalent form of peripheral arterial aneurysms. Greater saphenous vein grafts and endoaneurysmorrhaphy remains the mainstay therapy for open repair of PAA. True aneurysmal degeneration of lower extremity infrainguinal autologous vein grafts are relatively rare and its etiology is not completely understood. CASE PRESENTATION: We present a case of a 57-year-old man with recurrent autologous venous graft aneurysmal dilatations following a surgical popliteal artery aneurysm repair. DISCUSSION: The pathogenesis of true aneurysmal graft dilatation remains speculative with possible pathogenesis including progression of underlying atherosclerosis, systemic dilating diathesis, autologous venous graft varicosities, low-grade infections and post-stenotic dilatations. Management of venous graft aneurysms should be subjected to the same criteria as other aneurysms. Diagnosis requires a high index of suspicion. The initial study of choice is duplex ultrasonography as it can diagnose the aneurysm and distinguish it from other popliteal masses, provide accurately measurements and identify thrombus within the aneurysm. Once diagnosed, surgical repair should be performed as soon as possible as graft dilatation tends to occur overtime and is typically followed by a rapid increase in size over a short period of time. CONCLUSION: Aneurysmal degeneration of autologous saphenous venous graft following PAA repairs occur infrequently. Its etiology remains largely speculative. Accurate diagnosis and early surgical intervention can prevent progression of aneurysmal dilatation and minimize the potential of complications.

Hybrid resection of a giant thigh plexiform neurofibroma.

PRESENTATION OF CASE: Authors present a case of a 55 year old patient with Type 1 neurofibromatosis (NF1) and a very large right thigh plexiform neurofibroma. The patient had increasing difficulty with mobilization due to this enlarging bulky mass. Preoperative embolization reduced the bleeding risk at surgery allowing successful gross resection of the mass by a multidisciplinary surgical team. Limb function was restored to normal. DISCUSSION: Massive plexiform neurofibromatosis is a rare expression of von Recklinghausen's disease or NF1. These large masses result in severe disfigurement and significant functional disability. They are extremely vascular and there is potential for malignant transformation. CONCLUSION: These massive tumors require complex preoperative, intraoperative and postoperative management strategies with involvement from a multidisplinary team. We discuss the challenges of surgical intervention and to discuss the current literature.

Continuous regional anaesthesia provides effective pain management and reduces opioid requirement following major lower limb amputation.

OBJECTIVES: Postoperative stump pain after major lower limb amputation is a significant impediment to the recovery of amputees. The vast majority of patients require opioid analgesics following surgery, which are associated with opioid-related side-effects. Here, we investigate whether intraoperative placement of a peripheral nerve stump catheter followed by continuous infusion of local anesthetic is as effective at pain control as current analgesic practices. If beneficial, this procedure could potentially reduce post-amputation opioid consumption and opioid-related adverse effects. METHODS: A retrospective chart review was conducted of 198 patients over a 4-year period who had undergone a major lower limb amputation for indications related to peripheral vascular disease. Postoperatively, 102 patients received a perineural catheter were compared to 96 patients who did not. The primary outcomes of this study were the amount of morphine equivalents used in the first 72 hours postoperatively and postoperative pain intensity in the first 24 hours. RESULTS: A total of 198 lower-limb amputations were selected for analyses. Multiple regression analyses indicated that perineural catheter use was associated with a lower cumulative postoperative opioid consumption over the first 72 hours but not postoperative pain scores at 24 hours. Perineural catheter use led to a 40% reduction in opioid use during the first 72 hours postoperatively. Mixed model repeated measures analysis demonstrated that this opioid reduction was consistent over time. Other variables related to total opioid use included age, pre-surgical chronic pain, pre-surgical opioid use, patient-controlled analgesia. CONCLUSIONS: Continuous perineural infusions of local anesthetic are a safe and effective method for reducing post-amputation opioid analgesic medications after major lower limp amputation.

Patient knowledge of peripheral vascular disease in an outpatient setting: an Achilles heel?

Peripheral vascular disease (PVD) has numerous modifiable risk factors. This study aimed to establish patients' awareness of risk factors and causes of PVD and their understanding of mechanisms of secondary prevention. A prospective survey of awareness of PVD among patients attending a tertiary vascular clinic for management of peripheral vascular disease was undertaken. Institutional review board approval was granted. Statistical analysis was performed using SPSS version 18.0 software. There was a 100% response rate, with 97 participants (53 male). Seventeen patients (19%) reported an interval of greater than six months from the onset of symptoms to first seeking medical attention with their General Practitioner. Only 19 (20%) could correctly identify 3 or more risk factors for peripheral vascular disease. Patients have limited awareness of PVD and its consequences. Educational initiatives are needed to encourage patients to seek early medical attention and raise awareness of modifiable risk factors in the community.

Regionalization of services improves access to emergency vascular surgical care.

Management of vascular surgical emergencies requires rapid access to a vascular surgeon and hospital with the infrastructure necessary to manage vascular emergencies. The purpose of this study was to assess the impact of regionalization of vascular surgery services in Toronto to University Health Network (UHN) and St Michael's Hospital (SMH) on the ability of CritiCall Ontario to transfer patients with life- and limb-threatening vascular emergencies for definitive care. A retrospective review of the CritiCall Ontario database was used to assess the outcome of all calls to CritiCall regarding patients with vascular disease from April 2003 to March 2010. The number of patients with vascular emergencies referred via CritiCall and accepted in transfer by the vascular centers at UHN or SMH increased 500% between 1 April 2003-31 December 2005 and 1 January 2006-31 March 2010. Together, the vascular centers at UHN and SMH accepted 94.8% of the 1002 vascular surgery patients referred via CritiCall from other hospitals between 1 January 2006 and 31 March 2010, and 72% of these patients originated in hospitals outside of the Toronto Central Local Health Integration Network. Across Ontario, the number of physicians contacted before a patient was accepted in transfer fell from 2.9 ± 0.4 before to 1.7 ± 0.3 after the vascular centers opened. In conclusion, the vascular surgery centers at UHN and SMH have become provincial resources that enable the efficient transfer of patients with vascular surgical emergencies from across Ontario. Regionalization of services is a viable model to increase access to emergent care.

Anomalous splenic artery aneurysm.

Aneurysms of the splenic artery are the most common visceral aneurysm. A splenomesenteric trunk, which involves the splenic artery arising from the superior mesenteric artery (SMA), is rare and occurs in less than 1% of patients. Thus splenic artery aneurysms (SAAs) with an anomalous origin from the SMA are quite rare. We report our experience with the surgical management of a 2.6-cm aneurysm involving a splenic artery arising from the SMA in a 40-year-old woman. This was treated with surgical resection with preservation of the spleen. A discussion about SAAs and the management of aneurysms arising from a splenomesenteric trunk follows.

Anomalous splenic artery aneurysm.

Aneurysms of the splenic artery are the most common visceral aneurysm. A splenomesenteric trunk, which involves the splenic artery arising from the superior mesenteric artery (SMA), is rare and occurs in less than 1% of patients. Thus splenic artery aneurysms (SAAs) with an anomalous origin from the SMA are quite rare. We report our experience with the surgical management of a 2.6-cm aneurysm involving a splenic artery arising from the SMA in a 40-year-old woman. This was treated with surgical resection with preservation of the spleen. A discussion about SAAs and the management of aneurysms arising from a splenomesenteric trunk follows.

Infected pseudoaneurysm of the superficial femoral artery in a patient with Salmonella enteritidis bacteremia.

Mycotic aneurysms, defined as irreversible dilation of an artery due to destruction of the vessel wall by infection, are rare but are associated with a high risk of rupture if not treated promptly. The case of a healthy 52-year-old smoker who presented with pyrexia, rigors, night sweats and severe right leg pain with swelling is presented. He was diagnosed with a superficial femoral artery mycotic aneurysm, with Salmonella enteritidis as the causative agent. He was treated with high-dose antibiotics, local debridement and autologous reconstruction. A high index of suspicion is needed to make the correct diagnosis in these cases. Prompt surgical intervention and antimicrobial therapy are the cornerstones of treatment to reduce the associated high morbidity and mortality.

Les anévrismes mycosiques, définis comme la dilatation irréversible d'une artère causée par une destruction de la paroi découlant de l'infection, sont rares mais s'associent à un risque élevé de rupture s'ils ne sont pas traités rapidement. Les auteurs exposent le cas d'un fumeur en santé de 52 ans qui a consulté à cause d'une pyrexie, de frissons, de sueurs nocturnes et de graves douleurs à la jambe droite accompagnées d'un œdème. Il a reçu un diagnostic d'anévrisme mycosique de l'artère fémorale superficielle causée par une Salmonella enteritidis. Il a reçu de fortes doses d'antibiotiques, un débridement local et une reconstruction autologue. Il faut un indice de présomption élevé pour poser le bon diagnostic. Une intervention chirurgicale et une thérapie antimicrobienne amorcées rapidement sont la pierre angulaire du traitement pour réduire la morbidité et la mortalité élevées qui s'associent à ce problème.

Cannulation of the right axillary artery for extracorporeal circulation in aortic surgery through a left thoracotomy: a novel technique.

Extensive aortic disease, such as atherosclerosis with aneurysms or dissections that involve the ascending aorta, can complicate the choice of a cannulation site for cardiopulmonary bypass. Antegrade selective cerebral perfusion through the right axillary artery has proved to be a reliable and valuable method for cerebral protection in aortic surgery. In the supine position it is an artery straightforward to access, it is more complicated in the right thoracoabdominal position. We present an innovative method of axillary artery cannulation for patients requiring surgery through a left thoracotomy.

Heparin-induced thrombocytopenia in the presence of a heparin-bonded bypass graft.

The use of prosthetic grafts in below-knee bypasses may be necessary in patients with no available autologous vein and critical limb ischemia not amenable to angioplasty. Such conduits, however, have generally yielded disappointing results. A new, heparin-bonded, expanded polytetrafluoroethylene graft (Gore Propaten vascular graft) designed to provide resistance to thrombosis may be associated with decreased early graft failure and increased patency. A concern with exposure to heparin, and therefore heparin-bonded prostheses, is the development of heparin-induced thrombocytopenia (HIT). Although rare, this requires prompt graft removal. We present a case to highlight this serious complication and review the literature on this topic.

Current prescribing patterns of elastic compression stockings post-deep venous thrombosis.

OBJECTIVES: Post-thrombotic syndrome (PTS) is a complication of deep vein thrombosis (DVT) characterized by chronic pain, swelling and heaviness, and may result in ulceration. Elastic compression stockings (ECS) worn daily after DVT appear to reduce the incidence and severity of PTS. The aims of our study were to investigate practices and perceptions of DVT patients and physicians regarding the use of ECS after DVT. METHODS: Two surveys were conducted. The first was sent to 225 staff and trainee clinicians and the second was administered to 150 DVT patients. RESULTS: The results demonstrated that the majority of senior staff (75%) believed that ECS were effective in preventing PTS and in managing venous symptoms. However, this was in contrast with junior trainees (21%) (P < 0.05). This resulted in only 63% of patients being prescribed ECS post-DVT. There was a lack of consensus as regards the optimal timing of initiation of ECS, duration of therapy and compression strength. Nearly all DVT patients who were prescribed ECS purchased them, 74% wore them daily, and most (61%) reported that ECS relieved swelling and symptoms. Physicians correctly predicted the main reasons for non-compliance, but misjudged the scale of patient compliance with ECS. CONCLUSIONS: Our findings suggest that there is a lack of consensus among doctors regarding ECS use after DVT and widespread education regarding the latest evidence of the benefit of ECS after DVT.

Endovascular ruptured abdominal aortic aneurysm repair--setting up your hospital for an endovascular approach.

In recent years, major improvements have been made, making elective repair of abdominal aortic aneurysm (AAA) a safe procedure. In selected series, mortality rates are less than 5%. Many of the patients with AAA, however, remain asymptomatic until they present with rupture. Once rupture has occurred, the overall mortality approaches 90%. Despite many advances in the management of ruptured AAA, the mortality rate of conventional open surgery has not improved significantly during the last 15 years. Over the last decade, endovascular techniques have been used increasingly to repair AAA, and there is increasing evidence that endovascular aneurysm repair (EVAR) is technically feasible and safe for ruptured AAA. This review studies the evidence and aids the clinician in setting up a practice to manage rAAAs utilizing an endovascular approach.

Neoadjuvant aortic endografting.

The advent and success of endovascular repair of abdominal aneurysms led to the development of catheter-based techniques to treat thoracic aortic pathology. Such diseases, including thoracic aortic aneurysms, acute and chronic type B dissections, penetrating aortic ulcers, and traumatic aortic transection, challenge surgeons to perform complex open operative repairs in high-risk patients. The minimally invasive nature of thoracic endografting provides an attractive alternative therapy. We present two cases of covered stent grafts deployed in the thoracic aorta to perform resection of the aortic wall infiltrated by malignancy in order to avoid a major vascular intervention and a traditional vascular graft interposition. This may become a potential new utility for aortic endografts.

Iliopsoas abscess: a re-emerging clinical entity not to be forgotten.

Iliopsoas abscesses are relatively rare clinical entities. They present with subtle and non-specific symptoms and as a result the diagnosis is often delayed, leading to significant morbidity and mortality. With an increasing number of immunocompromised patients in the population the prevalence of this condition is set to rise. Therefore, early diagnosis and appropriate management remain a challenge for clinicians. We present three patients with iliopsoas abscesses, two of which were primary and one of which was secondary to Crohn's disease. The average age of patients was 59 years and both patients with primary psoas abscesses were male. All presented with non-specific symptoms. Psoas sign was present in only one patient. CT confirmed the diagnosis in all cases. Treatment consisted of appropriate antibiotic cover and associated percutaneous drainage. The psoas abscess that was secondary to underlying Crohn's disease was subsequently treated with surgical excision of the affected segment of bowel and lavage of the abscess cavity. A high index of suspicion is required to ensure the accurate and early diagnosis of this rare clinical entity. Abdominal CT scanning remains the gold standard for diagnosis. Management is with appropriate antibiotics and adequate drainage. This can be achieved by either percutaneous or surgical drainage. Such treatment can reduce the overall morbidity and mortality of this condition.

Neoplasms escape selective COX-2 inhibition in an animal model of breast cancer.

BACKGROUND: Cyclo-oxygenase-2 (COX-2) is up-regulated in malignant tumours rendering it an attractive target for cancer therapeutics. However, whether long-term antagonism maintains its initial efficacy on established tumours is unclear. METHODS: 4T1 cells were injected into the mammary fat pad of BALB/c mice (n = 8). Once tumour deposits were established, animals were randomized into two equal groups to receive either a selective COX-2 inhibitor (SC-236) or a drug vehicle. Further animals similarly treated (n = 7) were studied in diuresis cages allowing urine capture and analysis by mass spectrometry to determine Prostaglandin F-1 levels (PGF-1). In addition, both wild-type receiving SC-236 and COX-2 knockout mice receiving either SC 236 or vehicle were subjected to the same studies to determine whether tumour-derived or host-derived (stromal) COX-2 was the critical element. Finally, BALB/c mice with 4T1 tumours (n = 7) were treated with a combination of COX-2 and lipoxygenase (LOX) inhibition to attenuate this escape phenomenon. RESULTS: While selective COX-2 inhibition initially retarded tumour growth, a rapid increase in tumour growth rate occurred later (day 9). This escape phenomenon correlated with an increase in urinary PGF-1 levels. An identical trend was also observed whether COX-2 knockout mice received SC-236 or not, suggesting that this effect is due to increased tumour-derived COX-2 production rather than recovery of host COX-2 functional capacity. Finally, dual inhibition of COX and LOX pathways attenuated this escape process. CONCLUSION: The anti-neoplastic effects of selective COX-2 inhibition may not be sustained as tumours demonstrate an escape capacity. However, this phenomenon maybe attenuated by a combination of COX/LOX inhibitors.

Emergency appendicectomy in the era of laparoscopy: a one-year audit.

BACKGROUND: Appendicectomy for acute appendicitis is the commonest emergency surgical operation. With widespread acceptance of minimal access surgery most appendicectomies are now performed laparoscopically. AIMS: The aim of this study was to assess whether the rate of normal appendicectomy has changed following the introduction of laparoscopic techniques in our institution. METHODS: A retrospective study of patients having emergency appendicectomies over a 1-year period (2005) in a large teaching hospital was undertaken. RESULTS: A comparison of data was made from a prior study performed at the same hospital in 1988. 196 adult patients underwent appendectomies during this period. The normal appendectomy rate was 10.2% compared to 22.8% in the previous study. This rate was twice as high in women of reproductive age as compared to men. CONCLUSION: There has been widespread uptake of laparoscopic appendectomy in our hospital. This technique has reduced the rate of histologically normal appendicectomies due to intra-operative visualization of the appendix.

Doctors' attitudes about prescribing and knowledge of the costs of common medications.

INTRODUCTION: Compliance with medical therapy may be compromised because of the affordability of medications. Inadequate physician knowledge of drug costs may unwittingly contribute to this problem. METHODS: We measured attitudes about prescribing and knowledge of medication costs by written survey of medical and surgical non consultant hospital doctors and consultants in two University teaching hospitals (n = 102). Sixty-eight percent felt the cost of medicines was an important consideration in the prescribing decision, however, 88% often felt unaware of the actual costs. Only 33% had easy access to drug cost data, and only 3% had been formally educated about drug costs. Doctors' estimates of the cost of a supply of ten commonly used medications were accurate in only 12% of cases, too low for 50%, and too high for 38%. CONCLUSIONS: Interventions are needed to educate doctors about drug costs and provide them with reliable, easily accessible cost information in real-world practice.