Jonathan Ghosh

Access for Endovascular Aneurysm Repair

Despite advancement in stent-graft technology, access-related problems continue to occur during endovascular repair of aortic aneurysms. Various techniques have been adopted to overcome difficult access situations, however. To survey these developments in arterial access, we performed a systematic literature review from 1994 through 2005 to identify relevant articles pertaining to endovascular access techniques and complications. Excessive iliac tortuosity, circumferential vessel wall calcification, significant occlusive disease, and small caliber vessels account for the majority of access problems, most of which are readily apparent with adequate baseline imaging. Even with careful preoperative assessment, however, some access problems may not be foreseen; nonetheless, the majority can be overcome using todays array of ancillary procedures, such as an iliac conduit, a brachiofemoral wire, or arterial reconstruction. Alternatively, other approach routes, such as the common carotid artery or direct aortic access, may be used to facilitate endovascular aneurysm repair.

A systematic review of open versus endovascular repair of inflammatory abdominal aortic aneurysms.

INTRODUCTION Inflammatory abdominal aortic aneurysms (IAAAs) have traditionally been treated by open surgical repair (OSR). Over the last decade, endovascular aneurysm repair (EVAR) has been increasingly employed. The optimal treatment option for IAAA remains unclear. This article aims to evaluate and compare outcomes of OSR and EVAR in IAAA repair. METHODS All publications in the English language relating to IAAA were sought electronically using OVID and MEDLINE (1972-2008). Studies identifying 30-day mortality were considered. Periaortic inflammation (PAI), hydronephrosis and 1-year mortality were obtained from studies with at least 1-year computed tomography (CT) follow-up. Outcomes of OSR and EVAR were compared and analysed for statistical significance using Fishers exact test. RESULTS The results were obtained from 35 studies comprising 999 patients and 21 studies with 121 patients who underwent OSR and EVAR, respectively. One-year CT follow-up was available for 124 and 52 patients from the two groups, respectively. Thirty-day mortality after OSR was 6% (95% confidence interval (CI); 6-13) and 2% (95% CI; 0-7) after EVAR (p=0.1). At 1 year, PAI regressed in 73% (95% CI; 64-80) in the OSR group compared to 65% (95% CI; 49-77) of the EVAR group (p=0.7). Conversely, inflammation progressed in 1% and 4%, respectively (p=0.1). Forty-five patients undergoing OSR and 29 EVAR were found to have preoperative hydronephrosis. This regressed postoperatively in 69% (95% CI; 53.3-81.8) and 38% (95% CI; 20.6-57.7), respectively (p=0.01). Hydronephrosis progressed in 9% of patients after OSR and in 21% after EVAR (p=0.1). New-onset hydronephrosis developed in 6% undergoing OSR compared to 2% with EVAR (p=0.2). One-year all-cause mortality after OSR was 14% (95% CI; 6-18) compared to 2% (95% CI; 0-13) after EVAR (p=0.02). CONCLUSION Either OSR or EVAR may be considered based on patient suitability. EVAR is associated with lower 1-year mortality compared to OSR. However, OSR may be preferred in those patients who have hydronephrosis and are deemed low risk.

Contemporary Management of Aorto-iliac Aneurysms in the Endovascular Era

Up to 40% of abdominal aortic aneurysms have co-existing unilateral or bilateral iliac artery ectasia or aneurysm. These are associated with an increased risk of endoleak, morbidity and mortality following endoluminal repair. To reduce the adverse sequelae of internal iliac artery (IIA) occlusion, various open, endovascular and hybrid measures have been described to maintain perfusion to the pelvis. This review discusses the contemporary management of aorto-iliac aneurysm in the endovascular era with reference to the sequelae of IIA occlusion and the strategies to preserve IIA perfusion. Particular consideration is given to iliac bifurcation devices.

A Comparative Study of Carotid Atherosclerotic Plaque Microvessel Density and Angiogenic Growth Factor Expression in Symptomatic Versus Asymptomatic Patients

OBJECTIVE A challenge facing clinicians is identifying patients with asymptomatic carotid disease at risk of plaque instability. We hypothesise that locally released angiogenic growth factors contribute to plaque instability. METHODS Carotid endarterectomy specimens from eight symptomatic and eight asymptomatic patients were interrogated for microvessel density and angiogenic growth factor expression histologically using immunofluorescence, and biochemically using quantitative real-time polymerase chain reaction (q-RT-PCR). Bio-Plex suspension array was used to assess circulating biomarkers in venous blood from the same patients and six healthy age-matched controls. RESULTS Immunofluorescence demonstrated significantly greater neovessel density in symptomatic plaques (P=0.010) with elevated expression of hepatocyte growth factor (HGF) (P=0.001) and its receptor MET (P=0.011) than in asymptomatic plaques. The q-RT-PCR demonstrated up-regulation of Endoglin (CD105), HGF (P=0.001) and MET (P=0.011) in the plaques of symptomatic versus asymptomatic patients. Bio-Plex suspension array demonstrated elevated HGF (P=0.002) serum levels in symptomatic versus asymptomatic patients and healthy controls, and decreased platelet-derived growth factor (PDGF) (P=0.036) serum levels in symptomatic versus asymptomatic patients. CONCLUSION Plaque instability may be mediated by HGF-induced formation of new microvessels, and decreased vessel stability resulting from decreased PDGF. Suspension array technology has the potential to identify circulating biomarkers that correlate with plaque rupture risk.

Use of three-dimensional contrast-enhanced duplex ultrasound imaging during endovascular aneurysm repair

BACKGROUND Iodinated contrast during endovascular aneurysm repair (EVAR) is used with caution in patients with chronic kidney disease. Contrast-enhanced ultrasound (CEUS) imaging using nonnephrotoxic sulphur hexafluoride microbubble contrast is a novel imaging modality that accurately identifies and characterizes endoleaks during EVAR follow-up. We report our initial experience of using three-dimensional (3D) CEUS imaging intraoperatively as completion imaging after endograft deployment. Our aim was to compare intraoperative 3D CEUS against uniplanar angiography in the detection of endoleak, stent deformity, and renal artery perfusion during EVAR. METHODS The study enrolled 20 patients undergoing elective conventional infrarenal EVAR, after which a completion angiogram was performed and the presence of endoleak, renal artery perfusion, or device deformity were recorded. With the patient still under anesthetic, a vascular scientist blinded to angiographic findings performed 3D CEUS and reported on the same parameters. RESULTS Three endoleaks, one type I and two type II, were detected on uniplanar angiography and 13 endoleaks, 11 type II and two type I, were found using 3D CEUS imaging. Of note, one of these type I endoleaks was not seen on angiography, and this patient underwent balloon moulding of the neck with resolution of the endoleak on repeat imaging. Of the 11 type II endoleaks seen with 3D CEUS imaging, the inflow vessel was identified in nine cases. No graft deformity or limb kinking was seen in any patient. Both renal arteries could be visualized in 10 patients, whereas the target renal artery was seen in 11 patients. In the remaining patients, the renal arteries could not be visualized, mainly due to intra-abdominal gas or patient body habitus. CONCLUSIONS 3D CEUS imaging detected endoleaks not seen on uniplanar digital subtraction angiography, including a clinically important type I endoleak, and was also more sensitive than 2D CEUS imaging for the detection of the source of endoleak. This technology has the potential to supplement or replace digital subtraction angiography for completion imaging to reduce the use of x-ray contrast. Intraoperative 3D CEUS has been applied to allow safe EVAR with ultralow or no iodinated contrast usage in selected cases, without compromising completion imaging.

Abdominal aortic aneurysm repair: The carotid approach.

We present the case of a 61-year-old man with a 5.8 cm infrarenal aortic aneurysm with extensive iliac disease that did not permit conventional EVAR, who was also judged to be too high risk for open surgery. Despite these factors, the aneurysm was still successfully repaired using endovascular means and an alternative access technique. This involved a specially commissioned Zenith aorto-uniliac endograft reverse mounted onto a TX2 delivery device, delivered via the carotid artery.

Inflammatory Abdominal Aortic Aneurysms (IAAA): Past and Present

Aim: The aim of the study is to determine whether presentation and outcomes of inflammatory abdominal aortic aneurysms (IAAA) have changed over the last five decades. Methods: Comparison of current outcomes (January 2001 to December 2007) with results of the earliest report from our unit in 1972. Results: In contemporary series, 421 patients underwent AAA repair; 38 (9%) were IAAA. In 58% patients, IAAA was an incidental finding, whereas 42% patients were symptomatic with abdominal or back pain. Of those, 32% were ruptured IAAA. Male-to-female ratio was 12:1. Thirty-day mortality was 13%; elective 11.5%; emergency 17%. Comparison with 1972 study showed no change in the incidence and gender predilection. Presentation as an incidental finding and rupture increased 4- and 2-folds, respectively. Conclusion: The incidence and gender predilection of IAAA have remained unchanged. The 4-fold increase in the presentation as an incidental finding reflects current trends in patient evaluation.

In patients with ruptured abdominal aortic aneurysm does endovascular repair improve 30-day mortality?

Endovascular aneurysm repair (EVAR) has become widely adopted as the primary treatment modality for abdominal aortic aneurysm in the elective setting. However, equipoise exists regarding the use of this technology for acute ruptured aneurysms. A best evidence topic in cardiovascular surgery was written according to a structured protocol. The question addressed, whether a policy for endovascular repair as the primary mode of treatment for ruptured abdominal aortic aneurysms (rAAAs) would improve outcomes. One thousand three hundred and twenty-eight papers were found using the reported search; of these, 24 presented represent the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studies, study type, relevant outcomes, results, and study weaknesses of these papers are tabulated. The majority of data available derives from level 2b evidence, with only a single level 1b and no level 1a studies available. Appraisal of theses studies is constrained by limited patient numbers, selection bias and heterogeneity in treatment protocols between the reported series. The sole prospective randomised controlled trial comparing open and endovascular treatments found a 53% mortality amongst patients treated by either modality. This study was, however, underpowered and contrary to numerous cohort series that show reduced mortality with EVAR. The largest body of evidence is found in a co-operative multicentre cohort study spanning 49 institutions that showed superiority of EVAR over open repair in terms of 30-day mortality. We conclude that, within the limitations of the published literature to date, endovascular repair as the primary treatment for rAAA is achievable and appears to be associated with favourable mortality over open repair with appropriate case selection.

Cilostazol and peripheral arterial disease

Peripheral arterial disease is both common and disabling. Contemporary management of peripheral arterial disease is multimodal, encompassing both medical and interventional treatments. Cilostazol (Pletal™), a 2-oxoquinolone derivative, is currently licensed in the UK for the treatment of patients with intermittent claudication to improve their walking distance in the absence of tissue necrosis or rest pain. The therapeutic effects of cilostazol are thought to be mediated through antiplatelet, antiproliferative and vasodilatory activities. This review aims to provide an overview of the management of peripheral arterial disease focusing upon cilostazol pharmacotherapy.

Three-dimensional contrast-enhanced ultrasound improves endoleak detection and classification after endovascular aneurysm repair

Background: Three‐dimensional contrast‐enhanced ultrasound (3D‐CEUS) is a novel technology allowing surgeons to view duplex ultrasound images in three dimensions with ultrasound contrast highlighting blood flow in endoleaks after endovascular aneurysm repair (EVAR). It potentially reduces the need for computed tomography angiography (CTA) and catheter angiography. This study compares 3D‐CEUS with both CTA and the final vascular multidisciplinary team (MDT) diagnosis using all available imaging. Interoperator variability for detection of endoleak and the influence of 3D‐CEUS on patient management were studied. Methods: A consecutive 100 patients undergoing CTA for EVAR surveillance were invited to undergo standard CEUS and 3D‐CEUS on the same day, with 3D‐CEUS reported independently by two blinded vascular scientists. Presence and type of endoleak were compared between CTA, standard CEUS, 3D‐CEUS, and the final diagnostic decision made in the vascular MDT meeting. Interoperator reliability of 3D‐CEUS was analyzed using the &kgr; statistic. Results: The 100 paired CTA, CEUS, and 3D‐CEUS studies were analyzed. Compared with CTA, the sensitivity, specificity, positive predictive value, and negative predictive value of 3D‐CEUS to endoleak were 96%, 91%, 90%, and 96%, respectively. Compared with the MDT decision with access to all imaging modalities, the sensitivity, specificity, positive predictive value, and negative predictive value of 3D‐CEUS were 96%, 100%, 100%, and 96%. The &kgr; statistic for interoperator agreement was 0.89. Conclusions: 3D‐CEUS was more sensitive and accurate than CTA for endoleak detection and classification after EVAR. 3D‐CEUS is now our initial investigation of choice in cases of sac expansion during duplex ultrasound follow‐up or if there is diagnostic uncertainty on standard duplex ultrasound or CTA.