Robert S.M. Davies

Review of Direct Anatomical Open Surgical Management of Atherosclerotic Aorto-Iliac Occlusive Disease

BACKGROUNDnAortofemoral bypass(AFB), iliofemoral bypass(IFB), and aortoiliac endarterectomy(AIE) are the three most common techniques for anatomical open surgical revascularisation for patients with aorto-iliac occlusive disease(AIOD), but the optimal method of reconstruction is unknown.nnnAIMSnTo review and compare mortality, morbidity and short- and long-term patency rates for AFB, IFB and AIE in patients with AIOD reported in the English language literaturennnMETHODSnA MEDLINE(1970-2007) and Cochrane Library search for articles relating to AFB, IFB, AIE and AIOD was undertaken. Studies were included if: a) patency rates based on life-tables were available, and b) patient/study characteristics were reported.nnnRESULTSn29 studies(5738 patients) for AFB, 11 studies(778 patients) for IFB and 11 studies(1490 patients) for AIE were included. Operative mortality was 4.1% for AFB, 2.7% for IFB and 2.7% for AIE (p<0.0001). Systemic morbidity was 16.0% for AFB, 18.9% for IFB and 12.5% for AIE (p<0.05). Overall 5-year primary patency rates were 86.3%, 85.3% and 88.3% for AFB, IFB and AIE, respectively (p=NS).nnnCONCLUSIONnAorto-iliac endarterectomy was associated with significantly lower peri-operative morbidity and mortality rates compared with bypass grafting. All three techniques were equally effective in terms of long-term patency.

Surgical Versus Endovascular Reconstruction for Chronic Mesenteric Ischemia: A Contemporary UK Series

Objective: To assess the outcome of surgical (SR) and endovascular (ER) reconstruction for chronic mesenteric ischemia (CMI). Methods: Retrospective review of consecutive patients who underwent SR or ER for CMI in 3 UK vascular surgery units between 1996 and 2006. Early (<30 days; technical success, morbidity, mortality, length of hospital stay) and late (>30 days) outcomes (symptom recurrence, vessel/graft patency, reintervention, mortality) were assessed. Results: A total of 27 patients underwent 32 reconstructions (SR = 17, ER = 15). A total of 44 of 56 (79%) diseased arteries underwent SR (n = 26; bypass = 24, reimplantation = 2; occlusion = 16, stenosis = 10) or ER (n = 18; stenosis = 16, occlusion = 2). Perioperative mortality for SR and ER was 6% and 0%, respectively (P ≥ .99). Hospital stay was shorter following ER (mean, 4.3 vs. 14.2 days, P = .0003). Mean (range) follow-up for SR and ER was 34 (1-94) and 34 (0-135) months, respectively. At 2 years, SR demonstrated superior secondary patency (100% vs. 65%) and clinical patency (100% vs. 73%). Conclusions: Surgical mesenteric reconstruction is associated with significantly longer hospital stay, but superior long-term outcome compared to endovascular reconstruction.

Coagulation, fibrinolysis, and platelet activation in patients undergoing open and endovascular repair of abdominal aortic aneurysm

BACKGROUNDnEndovascular aneurysm repair (EVAR) is associated with an improved perioperative mortality compared to open surgical repair. This benefit may reflect reduced incidence of microvascular and macrovascular thrombotic complications after EVAR.nnnPURPOSEnThe purpose of this study was to review and compare the effects of abdominal aortic aneurysm (AAA), open surgical repair, and EVAR on coagulation, fibrinolysis, and platelet activation.nnnMETHODSnA MEDLINE (1966-2010) and Cochrane library search for articles relating to the effects of AAA, open surgical repair, and EVAR on hemostasis was performed utilizing and cross-linking terms such as clotting, fibrinolysis, AAA, EVAR, and open surgical repair. Studies with a small cohort of patients (less than 7) or in which values of assessed biomarkers were not included were rejected.nnnRESULTSnAAA is associated with increased thrombin generation, activity, and fibrin turnover as evidenced by increased plasma levels of thrombin-antithrombin III-complex (TAT), activated protein C-protein C inhibitor (APC-PCI), fibrin-monomer-fibrinogen (FM-F), F1+2, fibrinogen, and D-dimer. The extent of hemostatic derangement correlates with the volume of intraluminal thrombus. This procoagulant state is exaggerated in the immediate perioperative period after both open surgical repair and EVAR, but is attenuated at medium-term follow-up although not normalized.nnnCONCLUSIONnThe resultant prothrombotic diathesis after open surgical repair and EVAR may account for the high level of perioperative thrombotic complications.

Failure of Endovascular Stenting for Popliteal Cystic Disease

We describe an attempted endovascular stenting for popliteal artery stenosis secondary to adventitial cystic disease in a 56-year-old man with lifestyle-limiting claudication. Despite technical success, it remained patent only for 1 week, requiring interposition venous graft reconstruction eventually.

Changes in thrombin generation, fibrinolysis, platelet and endothelial cell activity, and inflammation following endovascular abdominal aortic aneurysm repair.

BACKGROUNDnAbdominal aortic aneurysm (AAA) is a chronic inflammatory condition associated with a prothrombotic, hypofibrinolytic diathesis that may increase the risk of cardiovascular events. The effect of endovascular aneurysm repair (EVAR) on this prothrombotic diathesis is not fully understood, especially over the medium and long term. A better understanding of these postintervention changes may improve the risk of cardiovascular complications in the long term. The purpose of this study was to examine thrombin generation, fibrinolysis, platelet and endothelial activation, and the inflammatory response during the 12 months following EVAR.nnnMETHODSnTwenty-nine patients (mean age, 76.9 years) undergoing EVAR for AAA (mean diameter 6.9 cm) had prothrombin fragment (PF) 1 + 2, thrombin-antithrombin complex (TAT), plasminogen activator inhibitor (PAI) activity, tissue plasminogen activator (t-PA) activity and antigen, soluble P- and E-selectin, and highly sensitive C-reactive protein (hsCRP) measured before and at 24 hours, and 1, 6, and 12 months after surgery.nnnRESULTSnPF1 + 2 were markedly elevated prior to EVAR and remained so at 24 hours and 1 month, but had decreased significantly at 6 and 12 months. TAT was also elevated prior to EVAR and increased still further by 24 hours, but fell to below baseline levels thereafter. PAI activity and t-PA antigen were normal prior to EVAR, increased significantly at 24 hours, and then fell to baseline levels. t-PA activity was only detectable at 1 and 6 months; there was a significant rise in soluble P- and E-selectin after EVAR, which was sustained for 12 months. hsCRP increased transiently in response to EVAR but returned to preoperative levels by 1 month.nnnCONCLUSIONSnThe prothrombotic, hypofibrinolytic diathesis associated with AAA is normalized 12 months after EVAR. This beneficial systemic effect of EVAR for AAA disease may help protect patients against future thromboembolic cardiovascular events.

Outcome in patients requiring renal replacement therapy after open surgical repair for ruptured abdominal aortic aneurysm.

Objective: To determine the relationship between postoperative renal replacement therapy (RRT) and patient survival after open surgical repair (OR) of ruptured abdominal aortic aneurysm (rAAA). Methods: A retrospective review of consecutive patients who underwent OR for rAAA repair between January 2002 and July 2008 was performed. Early (<30days) and late (>30days) outcomes were assessed. Results: A total of 94 patients (69 men; median [range] age 73.8 [56-89] years) underwent OR of rAAA (infrarenal = 78, juxtarenal = 15, and suprarenal = 1). In-hospital mortality rate was 40% and mean (range) length of intensive care unit (ICU) stay was 9.3 (0-56) days. A total of 23 (24%) patients required postoperative RRT. In-hospital mortality rate was significantly higher (RRT: 87% (20 of 23) vs no RRT: 18 of 71 (25%), P < .0001) and ICU stay significantly longer (RRT: mean (range) days; 14.8 (1-44) vs no RRT: 7.5 (0-56), P = .04) in the RRT patients. On multivariate analysis, RRT (P = .0053) and/or inotropic support (P = .0033) were independent risk factors for death within 30 days of the index procedure. Conclusions: Renal replacement therapy following OR of rAAA is an independent risk factor for mortality.

The relationship between aortic aneurysm sac thrombus volume on coagulation, fibrinolysis and platelet activity.

AIMnAbdominal aortic aneurysm (AAA) is associated with chronic mural inflammation and a pro-thrombotic diathesis. It has been suggested that both may be related to biologically active intra-sac thrombus. The aim of this study was to examine the relationship between thrombin generation, fibrinolysis, platelet activity and AAA sac thrombus volume.nnnMETHODSn30 patients (29 men) of median (IQR) age 75 (71-82) years with an infra-renal AAA >5.5 cm in antero-posterior diameter were prospectively studied. AAA, lumen and thrombus volumes were calculated using a CT workstation (Vitrea). Plasma thrombin-antithrombin (TAT), plasminogen activator inhibitor (PAI)-1, and soluble (s) P-selectin were measured as biomarkers of coagulation, fibrinolysis and platelet activity, respectivelynnnRESULTSnMedian (IQR) AAA total, lumen and thrombus volumes were 188 (147-247) cm(3), 80 (54.3-107) cm(3) and 97.6 (63-127) cm(3) respectively. TAT levels were significantly higher (median, QR, 7.15 [4.7-31.3] μg/L, p=<0.001) and sP-selectin levels significantly lower (median, IQR, 80.5 [68-128] ng/ml, p=<0.0001) than the normal range. PAI-1 levels (median, IQR, 20.9 [8.4-50.7] ng/ml) were normal. There was no correlation between AAA thrombus volume and PAI-1 (r=-0.25, p=0.47), sP-Selectin (r=0.26, p=0.43) or TAT plasma levels (r=-0.21, p=0.54).nnnCONCLUSIONnThe present study confirms that patients with AAA demonstrate haemostatic derangement, but the extent of the haemostatic derangement does not correlate with AAA sac thrombus volume.

Successful Glue Embolization of a Late Type 1a Endoleak Causing Abdominal Aortic Aneurysm Rupture

We describe the successful treatment with n-butyl cyanoacrylate embolization of a ruptured infrarenal abdominal aortic aneurysm caused by a late type-1A endoleak 10 years after endovascular aneurysm repair (EVAR).

Hybrid Open Endovascular Repair of Para-Anastomotic Common Iliac Artery Aneurysm in the Presence of Bilateral External Iliac Artery Occlusions

We describe a successful hybrid open endovascular repair of a large tender para-anastomotic common iliac artery aneurysm arising after previous open abdominal aortic aneurysm repair in a high-risk patient with bilateral chronic total external iliac artery occlusions.

Effect of endovascular and open abdominal aortic aneurysm repair on thrombin generation and fibrinolysis

BACKGROUNDnAbdominal aortic aneurysm (AAA) is associated with a prothrombotic diathesis that may increase the risk of cardiovascular events. This diathesis is exacerbated in the short term by open aneurysm repair (OAR) and endovascular aneurysm repair (EVAR). However, the effect of EVAR and OAR on coagulation and fibrinolysis in the medium and long term is poorly understood. The purpose of this study was to investigate the medium-term effects of EVAR and OAR on thrombin generation, neutralization, and fibrinolysis.nnnMETHODSnProthrombin fragment (PF)1+2, thrombin antithrombin (TAT) complex, plasminogen activator inhibitor (PAI) activity, and tissue-plasminogen activator (t-PA) antigen were measured in eight age-matched controls (AMCs), 29 patients with AAA immediately before (preoperatively) and 12 months after EVAR (post-EVAR), and in 11 patients at a mean of 16 months after OAR (post-OAR).nnnRESULTSnPreoperatively, PF1+2 levels were significantly higher in patients with AAAs than in AMC. PF1+2 levels post-EVAR and post-OAR were significantly lower than preoperative values and similar to AMC. There was no significant difference in TAT, PAI, or t-PA between AMC, AAA preoperatively, and post-EVAR. Post-OAR, PAI activity was significantly higher than in preoperative patients.nnnCONCLUSIONSnAAA is associated with increased thrombin generation without upregulation of fibrinolysis. The prothrombotic, hypofibrinolytic diathesis observed in patients with AAA returns toward normal in the medium term after EVAR and OAR, although there is a trend toward decreased fibrinolysis post-OAR.