Ultrasonography alone can reliably locate parathyroid tumours and facilitates minimally invasive parathyroidectomy.

INTRODUCTION: Minimally invasive parathyroidectomy (MIP) is performed via a short incision (≤3cm). Previous studies have employed multiple imaging modalities including ultrasonography, sestamibi imaging and/or intraoperative parathyroid hormone assay. We present our eight-year experience of MIP using ultrasonography alone. METHODS: One hundred parathyroidectomies performed by a single surgeon between April 2004 and December 2012 were identified in a prospectively maintained database. All patients underwent ultrasonography including preoperative marking of the lesion by a single radiologist. No other localising diagnostic tests were performed. RESULTS: Of the 100 patients (69% female) who underwent parathyroidectomy, 93 had MIP. The median age of all cases was 58 years (range: 19-90 years). All patients exhibited an elevated parathyroid hormone level (median: 19pmol) in the presence of hypercalcaemia (median: 2.86mmol/l, range: 2.54-3.94mmol/l). Conventional surgery was indicated in seven patients owing to the need for concurrent thyroidectomy. The median operative time was 30 minutes (range: 10-130 minutes). Ultrasonography localised parathyroid tumour position correctly in 98% of patients who underwent MIP, and in 97% across both MIP and non-MIP groups. Postoperative complications requiring treatment included pancreatitis and symptomatic hypocalcaemia. Follow-up review at 6-8 weeks demonstrated that 86% of open cases (6/7) and 94% of MIP cases (87/93) were rendered normocalcaemic. CONCLUSIONS: Our study is the first to demonstrate that the sole use of ultrasonography including preoperative marking can localise parathyroid tumours correctly in 98% of cases suitable for MIP.

Procedural risk following carotid endarterectomy in the hyperacute period after onset of symptoms.

OBJECTIVES: There have been concerns that performing carotid endarterectomy (CEA) in the hyperacute period after onset of a transient ischaemic attack (TIA) or stroke may be associated with a significant increase in the procedural risk that could offset any long-term benefit to the patient. The aim of this audit was to determine the 30-day risk of stroke/death after CEA in symptomatic patients, stratified for delay from the most recent neurological event, mode of presentation, and age. METHODS: Retrospective audit in 475 recently symptomatic patients between October 1, 2008, and April 24, 2013. RESULTS: Forty-one patients (9%) underwent surgery <48 hours of their most recent event, with a 30-day death/stroke rate of 2.4% (1/41). The procedural risk was 1.8% in 167 patients who underwent surgery within 3-7 days (3/167), falling to 0.8% in 133 patients who underwent surgery between 8 and 14 days (1/133) and 0.8% in 134 patients whose surgery took place after >14 days had elapsed (1/134). Overall, 208 (44%) underwent surgery within 7 days of their most recent neurological event (30-day risk = 1.9%), while 341 (72%) underwent CEA within 14 days (30 day risk = 1.5%). There was no evidence of any systematic differences in procedural risk by operating in the hyperacute period relating to mode of presentation (TIA, stroke, amaurosis) or age (<80 years; >80 years). CONCLUSIONS: This audit found no evidence that the procedural risk was increased when CEA was performed in the hyperacute period whether this time period was defined as <48 hours, <7 days, or <14 days.

Closing the loop: a 21-year audit of strategies for preventing stroke and death following carotid endarterectomy.

The objective of this review was to identify causes of stroke/death after carotid endarterectomy (CEA) and to develop transferable strategies for preventing stroke/death after CEA, via an overview of a 21-year series of themed research and audit projects. Three preventive strategies were identified: (i) intra-operative transcranial Doppler (TCD) ultrasound and completion angioscopy which virtually abolished intra-operative stroke, primarily through the removal of residual luminal thrombus prior to restoration of flow; (ii) dual antiplatelet therapy with a single 75-mg dose of clopidogrel the night before surgery in addition to regular 75 mg aspirin which virtually abolished post-operative thromboembolic stroke and may also have contributed towards a decline in stroke/death following major cardiac events; and (iii) the provision of written guidance for managing post-CEA hypertension which was associated with virtual abolition of intracranial haemorrhage and stroke as a result of hyperperfusion syndrome. The pathophysiology of peri-operative stroke is multifactorial and no single monitoring or therapeutic strategy will reduce its prevalence. Two of the preventive strategies developed during this 21-year project (peri-operative dual antiplatelet therapy, published guidance for managing post-CEA hypertension) are easily transferable to practices elsewhere.

Disease specific biomarkers of abdominal aortic aneurysms detected by surface enhanced laser desorption ionization time of flight mass spectrometry.

INTRODUCTION: Biomarkers have the potential to improve the clinical management of patients with AAA. REPORT: A prospective, proteomics discovery study was undertaken to compare patients with AAA (n = 20) to matched screened controls (n = 19) for plasma protein expression. Surface-Enhanced-Laser-Desorption-Ionization Time of Flight Mass Spectrometry (SELDI ToF MS) coupled with Artificial Neural Networks (ANN) analysis identified six protein related diagnostic biomarker ions with a combined AUC of 0.89. DISCUSSION: This study discovered a signature plasma protein profile for patients with AAA and demonstrated that mass spectrometric based research for disease specific biomarker of AAA is feasible.

The war against error: a 15 year experience of completion angioscopy following carotid endarterectomy.

BACKGROUND: A policy of intra-operative transcranial Doppler (TCD) and completion angioscopy was previously associated with virtual abolition of intra-operative stroke (apparent upon recovery from anaesthesia) following carotid endarterectomy (CEA). The aims of this study were to determine whether the prevalence of technical error has diminished with experience and whether our monitoring/quality control policy was still associated with low rates of intra-operative stroke 20 years after its introduction. METHODS: Retrospective review of four consecutive cohorts of 400 patients undergoing CEA between October 1995 and March 2010 (1600 CEAS in total). RESULTS: One hundred four patients (7%) had thrombus removed following angioscopy and prior to flow restoration, while 31 (2.1%) underwent repair of a distal intimal flap. The prevalence of intimal flaps diminished from 4.9% in the first 400 patients to 0.8% in the last 400 patients (p = 0.006). By contrast, the prevalence of retained thrombus did not decline with experience (8.5%, 3.7%, 10.3% and 5.4% for the four consecutive periods). Intra-operative TCD and completion angioscopy was, however, associated with extremely low rates of intra-operative stroke (0.25%, 0.25%, 0.5% and 0.25% during the four study periods). CONCLUSION: Most intra-operative strokes probably follow embolisation of thrombus following restoration of flow. This can be prevented by angioscopy which has the advantage of being performed prior to flow restoration. Increasing experience was associated with a decline in the detection of intimal flaps, but not in the prevalence of retained thrombus. Even the most experienced of surgeons can still be responsible for inadvertent technical error.

Reprinted article "Subintimal angioplasty of femoropopliteal artery occlusions: the long-term results".

The technique of subintimal angioplasty has been attempted on 200 consecutive femoropopliteal artery occlusions of median (range) length 11 (2-37) cm. The principle of the technique is to traverse the occlusion in the subintimal plane and recanalise by inflating the angioplasty balloon within the subintimal space. The technical success rate was 159/200 (80%) and was not significantly different for occlusions <10 cm (81%, n = 73), 11-20 cm (83%, n = 63) or >20 cm (68%, n = 23), p = 0.20. There were no deaths nor limb loss resulting from the procedure. The median (range) ankle-brachial pressure index increased from 0.61 (0.21-1.0) preangioplasty to 0.90 (0.26-1.50) postangioplasty. The actuarial haemodynamic patencies of technically successful procedures at 12 and 36 months were 71% and 58% respectively, the symptomatic patencies were 73% and 61%. A multiple regression analysis showed that smoking multiplied the risk of reocclusion by 2.70 (p < 0.001), each additional run-off vessel reduced the risk by 0.54 (p < 0.001) and the risk increased by 1.73 (p = 0.020) for every 10 cm of occlusion length. In conclusion, the technical success rate (80%) of subintimal angioplasty for femoropopliteal occlusions is unrelated to occlusion length and for all procedures, including technical failures, cumulative symptomatic and haemodynamic patencies of 46 and 48% can be achieved at 3 years. The factors influencing long-term patency were smoking, the number of calf run-off vessels and occlusion length.

Is use of a Continuous Autotransfusion System beneficial in emergency abdominal aortic aneursym (AAA) surgery?

BACKGROUND: Allogeneic blood products have become a limited and expensive resource. The Continuous Autotransfusion System (CATS) has been promoted as a method for reducing the need for allogeneic blood transfusion. This study was undertaken to ascertain whether the use of CATS in emergency open AAA surgery has any benefits. METHODS: This is a retrospective study of all patients undergoing emergency open AAA surgery in our center during a 5-year period (between July 2004 and July 2009). Patients were identified from a prospectively maintained vascular database, and data were obtained from patient records. RESULTS: CATS was used in 69 emergency open AAA repairs. The median total blood loss was 3,500 mL (range: 751-13,796 mL) but the median volume of packed red blood cells produced by CATS was only 493 mL (~ 2 U). An average of 7 U (range: 0-19 U) of bank blood was still used despite the availability of CATS. The mean hemoglobin 24 hours postoperatively was 10.3 g/dL (6.4-14.1) with a hematocrit of 0.30. CONCLUSION: The use of CATS in emergency AAA surgery does not seem to reduce the use of allogeneic blood transfusion. This may be because of over transfusion, as reflected by relatively high postoperative hemoglobin levels.

The prognostic value of circulating big endothelin-1 in patients undergoing potentially curative resection for colorectal cancer.

AIM: Elevated circulating endothelin-1 (ET-1) has been demonstrated in patients with colorectal cancer (CRC). The aim of this study was to examine the prognostic value of plasma big ET-1, the stable precursor of ET-1, in cancer-specific survival in patients having curative surgery for CRC. METHOD: Seventy-seven patients undergoing potentially curative surgery for CRC between January 2000 and January 2001 were studied. Clinicopathological data were obtained from a prospectively maintained database including long-term follow-up information (median follow up 84 months). The influence of plasma big ET-1 and clinicopathological variables upon over cancer-specific survival was determined by univariate and multivariable analysis. RESULTS: On univariate analysis, advanced Dukes' stage, tumour size and patient age were associated with shortened overall survival. Advanced Dukes' stage was the only factor associated with shortened survival on multivariable analysis. Plasma big ET-1 showed no association with either overall or cancer-specific survival following CRC resection. CONCLUSION: Plasma big ET-1 appears to have no prognostic value in primary CRC.

Is there an association between angiotensin converting enzyme (ACE) genotypes and abdominal aortic aneurysm?

OBJECTIVES: There is strong evidence of a genetic predisposition to abdominal aortic aneurysm (AAA), however the genes involved remain largely elusive. Recently, two large studies have suggested an association between the angiotensin converting enzyme gene and AAA. This study aimed to investigate the possible association between the ACE insertion/deletion polymorphism and abdominal aortic aneurysm (AAA) in order to replicate the findings of other authors. DESIGN AND METHODS: A case-control study was performed including 1155 patients with aneurysms and 996 screened control subjects. DNA was extracted from whole blood and genotypes determined in 1155 AAAs and 996 controls using a two stage polymerase chain reaction (PCR) technique. RESULTS: The groups were reasonably matched in terms of risk factors for AAA. No association was found between the ACE gene insertion/deletion polymorphism and AAA in this study. CONCLUSIONS: This study cannot support the findings of previous authors and provides evidence against a link between the ACE gene insertion/deletion polymorphism and AAA.

Dual antiplatelet therapy prior to carotid endarterectomy reduces post-operative embolisation and thromboembolic events: post-operative transcranial Doppler monitoring is now unnecessary.

BACKGROUND: Thrombotic stroke following carotid endarterectomy (CEA) is preceded by high-grade embolisation (detected using transcranial Doppler (TCD)) and can be prevented by incremental doses of Dextran. However, this strategy is labour intensive and Dextran manufacture has now ceased. A randomised trial has suggested that a single 75 mg dose of Clopidogrel (administered the night before surgery in addition to daily 75 mg Aspirin) significantly reduces post-CEA embolisation. We hypothesized that this model of dual antiplatelet therapy might significantly reduce the need for adjuvant Dextran therapy. METHODS: Retrospective audit of prospectively acquired data in 297 patients undergoing CEA between 01.08.2006 and 30.07.2009. All received routine Aspirin (75 mg daily) in addition to a single 75 mg dose of Clopidogrel the night before surgery. All underwent completion angioscopy and those with a temporal window (n = 270) underwent intra- and post-operative TCD monitoring. RESULTS: High rate embolisation requiring Dextran (>25 emboli in any 10 min period) occurred in only 1/270 patients (0.4%), significantly less than the 3.2% rate in historical controls where Clopidogrel was not administered. There were no peri-operative deaths, but 3/297 patients suffered non-disabling strokes (intra-operative extension of a pre-existing deficit, haemorrhage into lentiform nucleus after hypertensive crisis, contralateral embolic stroke). The overall 30-day death/stroke rate (1.0%) was not-significantly lower than the 2.6% rate observed in the preceding 821 patients. CONCLUSIONS: 75 mg Clopidogrel administered the night before surgery (in addition to daily 75 mg Aspirin) was associated with a significant reduction in post-operative embolisation and Dextran utilisation. No ipsilateral thromboembolic ischaemic events occurred in this series. As a consequence of this audit, one dose of 75 mg Clopidogrel will continue to be given pre-operatively (in addition to daily 75 mg Aspirin) and routine post-operative TCD monitoring has now ceased.

Short leukocyte telomere length is associated with abdominal aortic aneurysm (AAA).

OBJECTIVE: Telomeres are specialised DNA structures present at the ends of linear chromosomes, which shorten with each successive cell division and the length of which represents cellular biological age. The aim of this study was to determine the relationship between abdominal aortic aneurysm (AAA) and white cell telomere length. METHODS: Peripheral blood samples were collected from 190 patients with AAA and 183 controls. Genomic DNA was extracted from white cells and telomere lengths determined using a chemiluminescence technique. RESULTS: The mean white cell telomere length was significantly lower in AAA patients compared to controls (median age 66 years in both groups), with a mean difference of 189 base pairs (bp) (95% confidence interval 77 bp to 301 bp, P=0.005). This relationship between case-control status and mean telomere restriction fragment (TRF) length did not change after adding other risk factors into a multiple regression model. The risk of having AAA doubled in patients with a mean TRF length in the lowest quartile compared to patients with a mean TRF length in the highest quartile (odds ratio 2.30, 95% Confidence Interval 1.28-4.13, P=0.005). CONCLUSION: Our data show that patients with AAA have shorter leukocyte telomere length compared to controls. This suggests that vascular biological aging may have a role in the pathogenesis of AAA.

The incidence of epidural abscess following epidural analgesia in open abdominal aortic aneurysm repair.

INTRODUCTION: Complications of epidural catheterisation can cause significant morbidity. Epidural abscess following epidural catheterisation is rare and the reported incidence is variable. The purpose of this study was to review the incidence of epidural abscess in patients undergoing open abdominal aortic aneurysm (AAA) repair. PATIENTS AND METHODS: A retrospective case note review of all patients having open AAA repair over a 5-year period. RESULTS: A total of 415 patients underwent open AAA repair between January 2003 and March 2008. Of these, 290 were elective procedures and 125 were for ruptured aneurysms. Six patients underwent postoperative magnetic resonance imaging of the spine for clinical suspicion of an epidural abscess. Two of these (0.48%) had confirmed epidural abscess and two superficial infection at the epidural site. CONCLUSIONS: The incidence of epidural abscess following epidural analgesia in patients undergoing open AAA repair within our department was 0.48%. Although a rare complication, epidural abscess can cause significant morbidity. Epidural abscesses rarely develop before the third postoperative day.

A systematic review and meta-analysis of endovascular repair (EVAR) for ruptured abdominal aortic aneurysm.

BACKGROUND: Endovascular abdominal aortic aneurysm (EVAR) repair has become a well-established technique in the treatment of elective abdominal aortic aneurysms (AAAs) due to proven benefits in mortality, hospital stay and operation time compared to open repair. The aim of this study was to estimate the mortality rate from EVAR due to ruptured abdominal aortic aneurysm (RAAA). METHODS AND MATERIALS: A systematic review and meta-analysis of all English language literature with information on mortality rates from EVAR for RAAA was conducted. RESULTS: The pooled mortality rate from RAAA after EVAR across 31 studies concerning 982 patients was 24% (95% confidence interval (CI) 20-28%). The pooled morbidity from 21 studies was 44% (95% CI 33-55%). The average procedure time was 155.1 min, with an intra-operative blood loss of 523 ml and hospital stay of 10.1 days. There is evidence of publication bias suggesting the mortality rate may be under-estimated. CONCLUSIONS: Mortality from EVAR for RAAA appears to be lower than that which is reported for open repair of RAAA. However, the high level of publication bias cannot be ignored and may actually indicate higher mortality rates.

Buttock claudication and erectile dysfunction after internal iliac artery embolization in patients prior to endovascular aortic aneurysm repair.

Coil embolization of the internal iliac artery (IIA) is used to extend the application of endovascular aneurysm repair (EVAR) in cases of challenging iliac anatomy. Pelvic ischemia is a complication of the technique, but reports vary as to the rate and severity. This study reports our experience with IIA embolization and compares the results to those of other published series. The vascular unit database of the Leicester Royal Infirmary was used to identify patients who had undergone IIA coil embolization prior to EVAR. Data were collected from hospital case notes and by telephone interviews. Thirty-eight patients were identified; 29 of these were contactable by telephone. A literature search was performed for other studies of IIA embolization and the results were pooled. In this series buttock claudication occurred in 55% (16 of 29 patients) overall: in 52% of unilateral embolizations (11 of 21) and 63% of bilateral embolizations (5 of 8). New erectile dysfunction occurred in 46% (6 of 13 patients) overall: in 38% of unilateral embolizations (3 of 8) and 60% of bilateral embolizations (3 of 5). The literature review identified 18 relevant studies. The results were pooled with our results, to give 634 patients in total. Buttock claudication occurred in 28% overall (178 of 634 patients): in 31% of unilateral embolizations (99 of 322) and 35% of bilateral embolizations (34 of 98) (p = 0.46, Fisher's exact test). New erectile dysfunction occurred in 17% overall (27 of 159 patients): in 17% of unilateral embolizations (16 of 97) and 24% of bilateral embolizations (9 of 38) (p = 0.33). We conclude that buttock claudication and erectile dysfunction are frequent complications of IIA embolization and patients should be counseled accordingly.

An "all-comers" venous duplex scan policy for patients with lower limb varicose veins attending a one-stop vascular clinic: is it justified?

OBJECTIVE: To determine whether clinical assessment could predict the correct management of patients with varicose veins (VVs), select those who would need duplex scanning, and identify deep venous reflux (DVR). METHODS: Prospective study of 342 consecutive limbs with VVs. These were divided into 3 groups: 170 (50%) limbs with primary VVs without skin changes (group I), 37 (11%) with recurrent VVs without skin changes (group II), and 135 (39%) with primary or recurrent VVs with skin changes (group III). Clinicians were asked to document whether they would normally request a duplex scan because of clinical uncertainty. Agreement between decision-making based on clinical and on duplex findings was documented. RESULTS: Agreement between clinical and duplex findings for groups I, II, and III was 82%, 59%, and 67%, respectively. In 112 cases (66%) in group I, clinicians felt certain about the diagnosis and yet duplex scanning revealed they were wrong in 12% of cases. In group II, clinicians would request a duplex scan because of clinical uncertainty in 30 (81%) cases. In group III, the sensitivity, specificity, positive and negative predictive value of clinical assessment in detecting DVR was 32%, 77%, 24%, and 83%, respectively. CONCLUSIONS: Clinical evaluation of patients with VVs is unreliable in planning their management. Clinicians can neither predict those who will require duplex scanning nor correctly identify DVR. Even experienced surgeons often "get it wrong" when assessing primary uncomplicated veins despite being certain about the diagnosis. Therefore, an "all-comers" duplex imaging policy should be implemented if optimal management is to be achieved.

Duplex imaging immediately prior to carotid endarterectomy.

INTRODUCTION: In this centre, angiography is used only in selected cases, whilst duplex ultrasound (DU) is the main imaging method prior to carotid endarterectomy (CEA). DU has no associated morbidity and so can be repeated immediately before surgery to detect changes in the carotid plaque or degree of stenosis. PATIENTS AND METHODS: We retrospectively examined our Vascular Surgery Audit database for the last 500 patients admitted for CEA. In each case, the DU scan was repeated immediately before surgery. RESULTS: From 500 admissions, repeat DU immediately prior to surgery detected 8 (1.6%) situations where CEA would no longer have been an appropriate intervention. In four cases, the degree of stenosis was found to be less than 70% on the repeat scan - in three cases the internal carotid artery (ICA) had occluded or sub-occluded and in one case there was a dissection of the ICA plaque. CONCLUSIONS: DU can be repeated, with no associated morbidity, immediately prior to surgery. Such a practice changes management decisions in 1.6% of admissions for CEA, allowing surgery unjustified by current evidence to be avoided. This policy also serves several other important purposes: it is a method of internal validation, provides a means of improving training of vascular technologists and of achieving quality assurance in DU techniques.

The effect of six different statins on the proliferation, migration, and invasion of human smooth muscle cells.

Intimal hyperplasia (IH) can occur after any vascular injury and results from smooth muscle cells (SMC) proliferation, migration, and invasion into the subintimal space. The purpose of this study was to investigate the effect of six different statins on the proliferation, migration, and invasion of human venous SMC. The statins were all used at their Cmax concentrations. SMCs were used to construct growth curves in the presence of 10% fetal calf serum or 10% fetal calf serum supplemented with the six statins. Migration and invasion experiments were performed using modified Boyden chambers. The invasion experiments were performed using Matrigel coated plates. We found that all of the statins significantly inhibited SMC proliferation compared to the platelet-derived growth factor control (ranging from fluvastatin 33% of control to pravastatin 72% of control, P = 0.03). SMC migration through uncoated polycarbonate membranes in presence of the six statins was significantly reduced (ranging from lovastatin 43% to pravastatin 57% of control, P = 0.006). All six statins also significantly reduced SMC invasion (ranging from fluvastatin 65% to simvastatin 87% of control, P = 0.002). We conclude that the inhibitory effect of statins on SMC proliferation, migration, and invasion is a class, rather than drug specific effect.

A comparison of six statins on the development of intimal hyperplasia in a human vein culture model.

OBJECTIVE: Intimal hyperplasia (IH) threatens the patency of up to 35% of saphenous vein (SV) bypass grafts. In addition to reducing cholesterol levels, statins may modulate smooth muscle cell proliferation and migration. Statins inhibit matrix metalloproteinase (MMP) activity. We therefore investigated the effect of six statins on neointimal formation and MMP activity in human SV organ culture. STUDY DESIGN: Human SV specimens were cultured for 14 days in the presence of six different statins and subsequently processed for measurement of neointimal thickness and MMP activity. The drug concentrations chosen corresponded to the manufacturers' Cmax. RESULTS: The six statins all significantly reduced IH development (P = 0.004) in association with reduced expression of proMMP-2 and 9 (P = 0.03) and reduced activity of activated MMP-2 and 9 (P = 0.03). CONCLUSION: This study suggests that the potential benefit of statins in reducing IH is a class effect and not confined to specific statins. The reduction of IH produced by statins may in part be due to their inhibition of MMPs.