Nicolas Abello

High incidence of venous thrombosis after surgery for abdominal aortic aneurysm

OBJECTIVE The incidence of venous thromboembolism (VT) after aortic abdominal aneurysm (AAA) surgery is imprecisely reported. On one hand, thromboprophylaxis has improved, on the other hand, AAA patients have become older and/or present worse comorbidities. Herein, we prospectively analyzed the incidence of VT in a continuous series of patients operated on for AAA repair and looked for predictive factors. MATERIALS AND METHODS Between January 1, 2005, and December, 31, 2006, 193 consecutive patients (177 men and 16 women), mean age 73 (range, 47-93) underwent elective AAA repair, 137 open (71%) and 56 endovascular (29%), in our institution. Thromboprophylaxis consisted of thigh-length compression bandages or stockings, early mobilization, and a daily subcutaneous injection of low-molecular-weight heparin (enoxaparin 40 mg per day). Patients with renal insufficiency or aged over 80 were given unfractionated heparin (5000 IU twice a day). Heparin was started between day 1 and day 5 (median = day 1) after surgery, according to the prescription of the surgeon. A bilateral lower limb duplex venous compression ultrasonography scan using 3 to 7.5 MHz transducers was systematically done before and after surgery in each patient. Two groups were considered: group 1 with postoperative VT (n = 17) and group 2 without (n = 176). The 17 patients with VT were compared with 51 patients randomly chosen among the 176 patients without VT. Different characteristics such as venous risk factors, preoperative antithrombotic treatment, anatomical features of the AAA, and perioperative data were studied. RESULTS Seventeen patients (8.1%) were diagnosed with postoperative VT (15 asymptomatic deep vein thrombosis [DVT] and 2 symptomatic pulmonary embolisms [PE]). VTE tended to be more frequent in open (10.2%) than endovascular (5.3%) repair (P = .28). Among perioperative data, delay to thromboprophylaxis was related to bleeding complication (P = .05) and blood transfusion (P = .02), and tended to be longer in VT patients (1.7 +/- 1.4 vs 0.9 +/- 0.9 day; P = .09). CONCLUSION Despite systematic prevention with heparin, surgery for AAA repair induces a high incidence of postoperative VT. This series mandates for vigilance about VT, with particular attention to the patients who received transfusion with fresh frozen plasma. Even though this series is one of the largest ever published on this topic, the rarity of the events calls for confirmation with a larger prospective study.

The impact of renal insufficiency on the outcome of carotid surgery is influenced by the definition used

BACKGROUND Renal insufficiency (RI) seems to be a source of complications after carotid endarterectomy (CEA). However, published studies do not use a common definition of RI. Our objective was to analyze the effects of RI on carotid surgery using three classifications of renal function. METHODS Using a prospective database, we studied renal function and postoperative complications in patients operated on between January 1, 2003 and December 31, 2008. Renal function was studied using the level of plasma creatinine, creatinine clearance calculated according to the Cockcroft formula, and to the Modification of Diet in Renal Disease (MDRD) equation. For each method, the patients were divided into three groups: normal renal function, moderate RI, and severe RI. The principal judgment criterion was the 30-day non-fatal stroke and death rate. RESULTS The analysis concerned 961 CEAs carried out in 901 patients. The 30-day non-fatal stroke and death rate was 2%. In the analysis of renal function using the level of creatinine, there was no statistical difference between the groups in the 30-day stroke and death rate (normal renal function: 1.8%, moderate: 2.7%, severe: 8.3%, P = .21). The analysis of renal function according to creatinine clearance calculated using the Cockcroft formula showed that in the severe RI group, the stroke and death rate was higher than in the other two groups (normal renal function: 1.7%, moderate RI: 1.4%, severe RI: 7.5%, P = .004). Analysis using the MDRD formula showed similar differences between the severe RI group and the other two with a higher rate of 30-day stroke and death (normal renal function: 1.4%, moderate RI: 1.7%, severe RI: 12.5%, P < .001). Subgroup analysis showed that among patients with severe RI according to the creatinine clearance, those with symptomatic carotid stenosis had the highest incidences of non-fatal stroke and death (Cockcroft, n = 19: 21.1%, MDRD, n = 10: 40%). CONCLUSION Severe RI is a risk factor for complications after carotid surgery. Creatinine clearance calculated according to the MDRD formula correlates most closely with these complications. Symptomatic patients with severe RI, according to the creatinine clearance, are at high risk with a very high level of postoperative complications.

Development of Abdominal Aortic Aneurysm Is Decreased in Mice with Plasma Phospholipid Transfer Protein Deficiency

Plasma phospholipid transfer protein (PLTP) increases the circulating levels of proatherogenic lipoproteins, accelerates blood coagulation, and modulates inflammation. The role of PLTP in the development of abdominal aortic aneurysm (AAA) was investigated by using either a combination of mechanical and elastase injury at one site of mouse aorta (elastase model) or continuous infusion of angiotensin II in hyperlipidemic ApoE-knockout mice (Ang II model). With the elastase model, complete PLTP deficiency was associated with a significantly lower incidence and a lesser degree of AAA expansion. With the Ang II model, findings were consistent with those in the elastase model, with a lower severity grade in PLTP-deficient mice, an intermediate phenotype in PLTP-deficient heterozygotes, and a blunted effect of the PLTP-deficient trait when restricted to bone marrow-derived immune cells. The protective effect of whole-body PLTP deficiency in AAA was illustrated further by a lesser degree of adventitia expansion, reduced elastin degradation, fewer recruited macrophages, and less smooth muscle cell depletion in PLTP-deficient than in wild-type mice, as evident from comparative microscopic analysis of aorta sections. Finally, cumulative evidence supports the association of PLTP deficiency with reduced expression and activity levels of matrix metalloproteinases, known to degrade elastin and collagen. We conclude that PLTP can play a significant role in the pathophysiology of AAA.

Influence of the Contralateral Carotid Artery on Carotid Surgery Outcome

BACKGROUND Any obstacle in the contralateral artery has long been considered a high risk for carotid surgery. Here, we report the results of a monocentric, continuous, consecutive, prospective series and present a review of the literature. METHODS All carotid endarterectomies performed under locoregional anesthesia in our department between 2003 and 2010 were recorded in a prospective database (n = 1,212). Different statuses of the contralateral carotid artery--occlusion (group O, n = 81) and stenosis of >60% (group S, n = 173)--were compared with a control group (group C, n = 958). A shunt was used in cases of clinical intolerance to clamping. The assessment criteria concerned the need for a shunt and the combined 30-day nonfatal stroke and death rate. A stepwise logistic regression was performed. RESULTS Overall, a shunt was necessary in 7.3% of cases. The proportion was greater in group O (25.9%, P < 0.001). Severe renal insufficiency (odds ratio [OR] = 1.94) and contralateral carotid occlusion (OR = 5.53) were the sole factors predicting the need for shunting. The overall 30-day nonfatal stroke and death rate was 2.5%, with no difference between groups (P = 0.738), and severe renal insufficiency was the single predictor of a poor outcome (OR = 3.11; 95% confidence interval: 1.21-7.97; P = 0.18). CONCLUSION In this series, and in a large review of literature, occlusion of the contralateral internal carotid artery increased the incidence of intolerance to clamping and thus the use of shunts but did not worsen postoperative morbidity and mortality. The presence of a stenosed contralateral carotid was not predictive of postoperative events. In our experience, the status of the contralateral carotid artery cannot be considered a high risk for carotid surgery.

Long-Term Results of Stenting of the Aortic Bifurcation

BACKGROUND To evaluate the long-term results in a multicentric continuous series of narrowing lesions of the aortic bifurcation treated with a kissing stent. METHODS From January, 1st 1999 to the December, 31st 2001, all of the patients (n = 80) presenting with stenosis of the aortic bifurcation (n = 15) and/or the 2 common iliac arteries (n = 65), treated with a kissing stent, in 8 teaching hospitals were collected retrospectively. The risk factors were smoking (91%), dyslipidemia (60%), arterial hypertension (42%) and diabetes (27%). In 84% of cases, the indication for treatment was claudication. The lesions were stenotic < 70% (n = 76) and/or thrombotic (n = 18). The associated lesions were external iliac stenoses (n = 21), common femoral stenoses (n = 19), femoro-popliteal stenoses (n = 42), arteriopathy in the leg (n = 35). Follow-up was clinical examination and Doppler US scan. RESULTS The success rate of the technique was 89%. There were 4 cases (5.3%) of residual stenosis and 4 cases (5.3%) of dissection. The length of the lesions treated in the aorta and the iliac arteries was respectively 17.1 ± 7 and 17.3 ± 9 mm. The stents were all placed as kissing stents, and had a mean diameter and a mean length of 13.75 mm and 56 mm in the aorta and 9 mm and 48 mm in the iliac arteries, respectively. At 5 years, 19 patients had required repeat angioplasty in the treated area, and 13 had undergone open surgery. Primary and assisted primary patency at 5 years were 64.5% and 81.8%, respectively. CONCLUSION Long-term follow-up of endovascular treatment with kissing stents for stenosis of the aortic bifurcation shows that this technique gives good results, though it does not justify doing away with classical revascularisation surgery, in a population with major cardiovascular risk factors.

Risk Index for Predicting Shunt in Carotid Endarterectomy

BACKGROUND To prevent ischemia during carotid endarterectomy, a routine or selective shunt can be set up in cases of insufficient cerebral perfusion during the carotid clamping. The aim of this study was to analyze predictive factors for shunting under locoregional anesthesia and to validate a risk index to predict shunt. METHODS Using a prospective database, we studied carotid endarterectomy performed under locoregional anesthesia between January 1, 2003, and December 31, 2010 (n=1,223). A shunt was used because of clinical intolerance of clamping in 88 cases (group S, 7.2%). Clinical, comorbidities, demographics, and duplex scan data were used to compare group S to a control group (group C, n=1,135, 92.8%). A multivariable logistic regression was performed to identify predictors of shunt. Coefficients were assigned to each predictor to propose a predictive score. RESULTS Patients in group S were significantly older than those in group C (75.6±7.8 years vs. 72.6±9.4 years, P<0.001). Other factors associated with a carotid shunt were female sex (odds ratio [OR]=2.41, 95% confidence interval [CI]: 1.54-3.78, P<0.001), systemic arterial hypertension (OR=2.478, 95% CI: 1.16-4.46, P=0.016), occlusion of the contralateral carotid artery (OR=6.03, 95% CI: 2.91-12.48, P<0.001), and 1 factor against the likelihood of a carotid shunt, a history of contralateral carotid surgery (OR=0.34, 95% CI: 0.12-0.93, P=0.037). The mean flow in the contralateral common carotid artery was 696.5±298.0 mL/sec in group S and 814.7±285.5 mL/sec in group C (P<0.001). Using those 6 items, we propose a prognostic score validated in our series and allowing to divided risk of intolerance of clamping into low-risk (≤6%), intermediate-risk (6.1%-15%), and high-risk (>15%) groups. CONCLUSIONS We have established the first version of a score that predicts the need for a shunt by studying factors associated with intolerance to clamping. The relevance of this score, validated in our series, must be confirmed and adjusted by studies based on a larger sample size.

Delay between symptoms and surgery for carotid artery stenosis: modification of our practice.

BACKGROUND Recent data from the literature concerning symptomatic carotid stenosis show that the long-term benefits of surgery are greater when the surgery is performed soon after the neurologic event, ideally within 2 weeks. Since 2009, following recommendations, we decided to perform surgery as quick as possible. The aim of the study was to determine whether this approach increased postoperative morbimortality and the way it could change our practice. METHODS Using a prospective database containing a consecutive and continuous series of 1,500 carotid endarterectomies performed between 2003 and 2012, we extracted the records concerning the 417 symptomatic carotid stenoses (27.8%). We compared the 30-day and long-term outcome in 3 groups of patients: those operated within 2 weeks of the neurologic event (early surgery group [ESG], n = 158, 37.9%), those operated between 16 days and 6 weeks after the event (deferred surgery group [DSG], n = 79, 18.9%), and those operated more than 6 weeks after the event (late surgery group [LSG], n = 180, 43.2%). In the second part, to assess the new management beginning 2009, patients were divided in 2 periods 2003-2008 (period A) and 2009-2012 (period B) and we compared the 2 periods descriptive data and outcome. The primary outcome was the 30-day combined stroke and death rate. Secondary end points were follow-up freedoms from mortality and stroke. RESULTS The mean time between symptom onset and surgery was 7.7 ± 3.8 days for the ESG, 28.3 ± 8.6 days for the DSG, and 89.4 ± 36.7 days for the LSG. In the 3 groups, the types of symptoms leading to the indication for carotid surgery were comparable, with a stroke in 221 cases (53.0%), a transient ischemic attack in 146 cases (35.40%), and amaurosis fugax in 50 cases (12.0%). The groups were comparable in terms of comorbidities. The overall 30-day stroke rate was 1.4% (6 cases), the 30-day death rate was 1.7% (7 cases), and the combined stroke and death rate was 3.4% (3.2% in the ESG, 5.1% in the DSG, and 2.8% in the LSG [P = 0.808]). Survival rates at 24, 48, and 60 months were, respectively, 95%, 78%, and 78% in ESG, 86%, 81%, and 81% in DSG, and 91%, 83%, and 74% in LSG (P = 0.78). Freedom from stroke at 60 months showed to be, respectively, 97% in ESG, 96% in DSG, and 91% in LSG (P = 0.32). During the period A (2003-2008), we had taken care of 217 symptomatic carotid artery stenosis patients (22.3% of stenosis) and during the period B (2009-2012), 200 symptomatic stenosis (37.9% of stenosis). During the period A, an early surgery (<15 days) had place in 31 cases (14.3%), and during the period B, in 127 cases (63.5%). The 30-day stroke and death rate was of 3.7% during the period A and of 3.0% during the period B (P = 0.455). The 24-month survival and stroke-free survival rates were comparable between the 2 periods. CONCLUSIONS In our experience, surgery for symptomatic carotid stenosis can be performed early without increasing the rate of postoperative and long-term outcome. We have modified our practice, performing more and more early surgery for symptomatic stenosis without any impact on the outcome.

Evaluation of a New Technique of Carotid Endarterectomy, the « Carotidoplasty »

Objectives: Two types of carotid endarterectomies (CE) are currently practiced, longitudinal CE with patch (CEP) or by eversion. We propose a new technique, the ‘‘carotidoplasty’’ (CP), which is freed from an excess length of the carotid bifurcation (sometimes problematic for the CEP) and of the stop of plaque (sometimes problematic for eversion). The objective of our study was to evaluate the results of CP in the short and long term. Materials and Methods: Technique: CP consists in a skeletonization of the carotid bifurcation to mobilize it, divide the internal carotid obliquely, and carry out a longitudinal arteriotomy of the carotid bulb then an endarterectomy of the bulb and external carotid. The internal carotid is endarterectomized a minima under visual control then obliquely reimplanted in the bulb by a circular running suture, which makes it possible to secure an atherosclerotic plaque if necessary, to correct a possible excess of length, and to obtain a quasi-anatomical restitution of the carotid bifurcation. From a prospective database, we studied the CE (n1⁄4748) carried out in our unit by CEP (n1⁄4624, 83.4%) and by CP (n1⁄4 73.9.8%) between January 1st, 2007 and December 31st, 2011. We analyzed the demographic criteria (sex, age, cardiovascular risk factors, and comorbidities), the degree of stenosis, the symptomatic character and the type of symptoms of the carotid stenoses, the status of the contralateral carotid, the type of anesthesia, the cross clamp time, the need for a shunt, the early reinterventions, and the longterm follow-up. The principal criterion of judgment was the CRMM (rate of stroke or death at 30 days). The secondary criteria of judgment were the rates of residual stenosis, of postoperative thrombosis, of restenosis, and of long term survival. Results: The average time of follow-up was 30.5 months (1 to 72 months). The significantly different elements between CP and CEP were: the age (75.8 years ± 8.9 vs 72.9 years ± 9.6, p1⁄4 0.015), the cross clamp time (36 min ± 7.6 vs 40.3 min ± 11.0, p1⁄40.005), and the rate of restenosis (0 vs 5.3%, p1⁄40.039), respectively. The CRMM were 0% vs 3.4%, respectively, without significance (p1⁄40.153). The other analyzed parameters were not different. Conclusion: The carotidoplasty, a new surgical technique, showed satisfactory results in the short and long term, in this monocentric experience. Its interest must be confirmed in more patients with a multicentric evaluation.