Basso Parente

Predictive factors and clinical consequences of proximal aortic neck dilatation in 230 patients undergoing abdominal aorta aneurysm repair with self-expandable stent-grafts.

OBJECTIVE Several studies have suggested that proximal aortic neck dilatation (AND) is a frequent event after balloon-expandable endografting. Yet few data are available on AND after repair with self-expandable stent grafts. To investigate incidence, predictive factors, and clinical consequences of AND, computed tomography (CT) scans obtained at intervals during follow-up of 230 patients who had undergone endoluminal abdominal aortic aneurysm (AAA) repair with self-expandable stents were reviewed. SUBJECTS Between April 1997 and March 2001, 318 patients underwent endoluminal AAA repair with a self-expandable endograft at our unit. CT scans obtained at 1 and 12 months after surgery and yearly thereafter were prospectively stored in a computer imaging data base. Two hundred thirty patients were available for minimum 1-year assessment. Two vascular surgeons with tested interobserver agreement reviewed 686 CT scans. Diameter of the proximal aortic neck was measured as the minor axis of the first CT section that contained at least half of the proximal portion of the endograft. For endografts with suprarenal attachment the first scan below the lowest renal artery was considered. Diameter change of 3 mm or more between the CT scan at 1 month and subsequent evaluations was defined as AND. Nine possible independent predictors of AND were analyzed with Cox regression analysis. RESULTS Median follow-up was 24 months (range, 12-54 months). In 2 patients, AAA ruptured during follow-up. CT scans for 65 patients (28%) showed AND. Thirteen patients with AND (5.6%) underwent repeat intervention, including positioning of the proximal cuff in 8 patients and late conversion to open repair in five patients. Of the nine variables examined with multivariate analysis, only 3, ie, presence of neck circumferential thrombus (hazard ratio [HR], 2.51; 95% confidence interval [CI], 1.26-5.01; P =.008), preoperative proximal neck diameter (HR, 1.21; 95% CI, 1.07-135; P =.001), and preoperative AAA diameter (HR, 1.03; 95% CI, 1.00-1.06; P =.046) were positive independent predictors of AND, whereas the other 6, ie, neck angulation more than 60 degrees, neck length, suprarenal fixation, oversizing more than 15%, endoleak at 30 days, and increased AAA diameter during follow-up, showed no significant correlation. Probability of AND at 48 months was 59 +/- 6.1 at analysis with the Kaplan-Meier method. CONCLUSIONS AND is a frequent sequela of endoluminal repair in the mid-term. Severe AND developed in a small percentage of our patients, compromising integrity of AAA repair. Patients with large aneurysms and aortic necks and patients with aortic neck circumferential thrombus are at high risk for aortic neck enlargement after endoluminal repair of AAA.

Comparison of Target Organ Damage in Renovascular and Essential Hypertension

In many reports, the prevalence of target organ damage in renovascular hypertension (RVH) appears to be higher than in essential hypertension (EH). Since in most studies the renal artery stenosis is part of a diffuse atherosclerotic disease, it is not known whether these complications are due to RVH itself or to the vascular disease. We have undertaken a case control study of 92 patients divided into two groups (46 in each), one with RVH and the other with EH and abdominal aortic aneurysm, with a comparable degree of diffuse atherosclerotic vascular disease. The vascular state of the extracranial carotid arteries and abdominal and inferior limb districts was investigated with angiography and sonography. The prevalence of left ventricular hypertrophy (LVH) and ischemic heart disease (IHD) were assessed by electrocardiography. Serum creatinine and urinary protein excretion were employed in the renal evaluation. While the analysis of the results confirmed an even diffusion of atherosclerotic vascular disease between the two groups, a significant difference was found in the prevalence of heart and renal damage. LVH was present in 32.6% of RVH patients versus 10.8% in EH (P = .02). Serum creatinine > 1.4 mg/dL was found in 50% of RVH and in 23.9% of EH, (P = .01). The prevalence of proteinuria in RVH was also higher although not reaching the statistical significance. The results suggest that, in patients with comparable degrees of atherosclerotic vascular disease, RVH is responsible for the higher prevalence of target organ damage in this condition compared to those with EH.

Transcranial Doppler monitoring during carotid endarterectomy: Is it appropriate for selecting patients in need of a shunt?☆☆☆★

PURPOSE This report summarizes our experience in evaluating a series of 168 patients who underwent a total of 175 carotid endarterectomy procedures under local anesthesia. Patients were monitored by stump pressure (SP) measurement and transcranial Doppler scanning (TCD). The need for shunting was compared between SP/TCD flow velocity reduction and the awake response (gold standard). METHODS The study cohort represented 56% of all the carotid patients treated during the study period. Clamping ischemia was defined as the appearance of focal deficit (focal ischemia) or unconsciousness (global deficit) on carotid clamping. In the case of clamping ischemia, a shunt was inserted. To define the optimal value of SP and TCD flow velocity that is able to discriminate patients with clamping ischemia, a receiver operator characteristic (ROC) curve was constructed. Sensitivity and specificity tests, together with negative and positive predictive values (NPV and PPV), were calculated. Cutoff values were defined as the ROC curve values that correlated the highest sensitivity with the highest specificity for both SP and TCD. RESULTS Clamping ischemia was present in 18 procedures (10%) in which a shunt was used. No perioperative deaths were recorded. Major perioperative morbidity occurred in one patient (0.6%). Two nondisabling strokes were also recorded (1.8% overall rate of neurologic morbidity). Cutoff values for both SP and TCD, using the ROC curve, were < or = 50 mm Hg and > or = 70% flow velocity reduction from baseline, respectively. SP values of < or = 50 mm Hg or less showed a sensitivity of 100%, a specificity of 83%, a PPV of 40%, and an NPV of 100%. TCD flow monitoring (> or = 70% flow reduction) revealed a lower sensitivity (83%) but a greater ability to avoid false positive results (96% specificity), resulting in increased PPV (71%) and NPV (98%). Combining SP and TCD failed to provide better results in terms of specificity (81%) and PPV (38%). CONCLUSIONS SP measurement using a 50 mm Hg cutoff appears to be a reliable predictor of clamping ischemia but requires the use of a shunt in 17% of the patients who would otherwise not require this procedure. In contrast, TCD has greater specificity but is associated with a lower sensitivity, with 17% false negative results. In our experience, both SP and TCD show limitations, as they overestimate or underestimate carotid endarterectomy procedures in need of a shunt. We believe that sensitivity is more important than specificity in carotid endarterectomy, and thus conclude that TCD flow velocity measurement is not an optimal method for detecting clamping ischemia.

Role of surgical techniques and operative findings in cranial and cervical nerve injuries during carotid endarterectomy

OBJECTIVE To establish the incidence of cranial and cervical nerve injuries during CEA and their relationship to different surgical techniques and operative findings. DESIGN A prospective study. PATIENTS AND METHODS From January 1994 to April 1995, 187 consecutive patients undergoing 190 CEAs were evaluated. Pre- and postoperative cranial and cervical nerve assessments were carried out by a single otolaryngologist, blinded to the operative technique and findings. Deficits lasting more than 12 months were defined as permanent. Logistic regression analysis was performed to evaluate the influence of surgical technique, type of anaesthesia, neck haematoma, and plaque extension on the onset of nerve injuries. RESULTS Postoperatively, nerve lesions were identified in 51 CEAs (27%) and non-neurological injuries (hemilaryngeal ecchymosis or oedema) causing postoperative dysphonia were present in 80 CEAs (42%). All non-neurological injuries were transient and 98% disappeared within 1 month of surgery. Thirteen (7%) nerve lesions were permanent, but none were disabling. Vagus nerve lesions were significantly associated with long (> 2 cm) carotid plaque (OR = 3.5; CI 1.09-12.37; p = 0.03). Cervical branch lesions were associated with the presence of neck haematoma (OR = 1.9; CI 0.7-4.7; p = 0.05). The incidence of single cranial nerve injuries was higher in patch (OR = 2.7) and eversion (OR = 1.9) procedures than in primary closure. Multiple deficits (2 or more) were most frequent in eversion CEAs (OR = 2.8) and in cases complicated by neck haematoma (OR = 3.8). CONCLUSIONS Cranial and cervical nerve lesions during CEA are common. However, our data showed that the majority of local complications are related to transient hemilaryngeal ecchymosis or oedema and, when permanent, are neither clinically relevant nor disabling at 1 year of follow up. Carotid plaque extension and neck haematoma appear to increase the incidence of cranial and cervical nerve lesions during CEA.

Elevated Lipid Peroxidation Biomarkers and Low Antioxidant Status in Atherosclerotic Patients with Increased Carotid or Iliofemoral Intima Media Thickness

Objectives Lipid peroxidation plays an important role in the development of atherosclerosis, a chronic, age-related disease process of the arterial wall with onset decades prior to its clinical manifestations. The aim of the study was to assess the association between the intima media thickness (IMT) of the major arteries as a clinical marker of atherosclerosis and markers of lipid peroxidation along with the antioxidant status in humans. Design Case-control study. Setting A university-affiliated outpatient clinic. Subjects Thirty patients (22 males, 8 females; 70.4 ± 7.3 years) with atherosclerosis of the carotid or iliofemoral arteries and 62 healthy controls (30 males, 32 females; 68.3 ± 4.3 years). Methods Plasma levels of 8,12-isoprostane F2α-VI (8,12-IPF2α-VI) were measured by gas chromatography/mass spectrometry, whereas levels of malondialdehyde (MDA), vitamins A (retinol) and E (α- and γ-tocopherol), and carotenoids were determined by high-performance liquid chromatography. The IMT was measured by B-mode ultrasonography. Results Patients showed, independent of fruit and vegetable intake, significantly lower plasma levels of retinol, α-tocopherol, and all carotenoids excluding β-cryptoxanthin compared with controls. On the contrary, plasma 8,12-IPF2α-VI levels were almost doubled (p < .001) and MDA levels increased by one-third (p < .01) in atherosclerotic patients compared with controls. Conclusions The analyses of isoprostanes and antioxidant nutrients in plasma as markers of oxidative stress and the parallel evaluation of IMT as a structural marker of atherosclerosis are suitable tools for investigating the role of antioxidants and oxidative stress in atherosclerosis.

ACE gene polymorphism and survival in atherosclerotic renovascular disease

Renovascular disease (RVD) is an important cause of end-stage renal disease and is associated with a high mortality rate, mostly because of coexisting cardiovascular and cerebrovascular disease. The deletion (DD) polymorphism of the angiotensin-converting enzyme (ACE) gene has been described in association with severe vascular disease affecting major organs. To investigate whether DD genotype is a risk factor for mortality in RVD, we performed a follow-up study of 61 patients with this disease. Patients (age, 68.0 +/- 6.5 years) affected by atherosclerotic vascular disease were enrolled after angiographic demonstration of a renal artery stenosis. The average follow-up was 48.1 +/- 14.9 months. Genotype was insertion/deletion (I/D) in 30 patients, DD in 27 patients, and II in 4 patients. At enrollment, a complete assessment of heart, blood vessels, and renal function was performed. During the follow-up period, 13 patients died (9 DD, 4 ID) and 7 patients evolved into end-stage renal failure. The cumulative survival rate at 5 years was 45.4% +/- 13.4%. Factors associated with mortality were analyzed with Cox proportional hazard regression. The multivariate analysis showed that DD genotype, severe carotid disease, and smoking were independent predictors of mortality. The multivariate analysis of predictors of renal failure showed that the only significant association was found with baseline serum creatinine level of 265 micromol/L or greater. We conclude that the DD genotype of the ACE gene is a marker for mortality in RVD.

Outcome of abdominal aortic endografting in high-risk patients: a 4-year single-center study.

Purpose: To evaluate feasibility, safety, and effectiveness of endovascular abdominal aortic aneurysm (AAA) repair in patients whose fitness for surgery is questionable. Methods: Between April 1997 and December 2001, 389 consecutive patients underwent endovascular AAA repair. Of these, 51 (13.1%) were ASA grade IV. The perioperative and late outcomes of this group were compared to the remaining 338 patients with ASA grades <IV. Failure of AAA exclusion was defined as late conversion to open repair, AAA rupture, increased aneurysm diameter, or persisting graft-related endoleak. Gender, age, ASA grade IV, EUROSTAR class E, and AAA diameter were examined by logistic regression analysis for their influence on perioperative death, survival, and failure of AAA exclusion. Results: Four (7.8%) perioperative deaths occurred in the ASA IV group compared to 1 (0.3%) in the ASA <IV group (p=0.001). Median follow-up was 22 months (range 1–56). Failure of AAA exclusion occurred in 3 (5.9%) patients in ASA IV group and in 25 (7.4%) in ASA <IV group (p>0.05). Actuarial survival at 30 months was 62.9% in ASA IV group and 88.0% in ASA <IV group (p=0.001, log-rank test). There were no independent predictors for failure of AAA exclusion; ASA IV was independently associated with perioperative mortality (HR 17.8; 95% CI 1.6 to 188; p=0.016). Conclusions: Endovascular AAA repair in ASA IV patients is feasible and effective in preventing AAA rupture in the mid term. High-risk patients experience a worse prognosis than their good-risk counterparts. An individualized approach in selecting high-risk patients for endoluminal repair is mandatory.

Computerised tomography findings as a risk factor in carotid endarterectomy: Early and late results*

OBJECTIVES To evaluate whether preoperative CT evidence of brain infarction is associated with an increased risk of early and late stroke and death in patients undergoing CEA. DESIGN Retrospective clinical study. MATERIALS AND METHODS We evaluated 844 CT scanning records from 893 patients undergoing CEA from 1986-1994: 43% (367) CT positive for cerebral infarction and 57% (477) negative. Univariate and multivariate analysis was performed for risk factors and preoperative symptoms in patients with positive and negative CT scans, and Kaplan Meier survival curves for late events. RESULTS A positive CT was significantly more frequent in males vs. females (p < 0.0001; O.R. 2.52; C.I. 1.73-3.73), diabetics vs. non-diabetics (p = 0.03; O.R. 1.52; C.I. 1.03-2.26), symptomatics vs. asymptomatics (p < 0.001; O.R. 2; C.I. 1.93-3.53) and contralateral occlusion vs. patency (p < 0.001; O.R. 2; C.I. 1.30-3.10). The perioperative disabling stroke/ death rate was higher in patients with a positive CT (p = 0.002; O.R. 6.27; C.I. 1.73-34.20); in asymptomatic patients this difference was striking (5 patients vs. O, p = 0.0002). Multiple logistic regression analysis for risk factors, CT findings, symptoms preceding surgery, and congruity of brain infarction confirmed a significantly higher incidence of perioperative stroke/death rate (p = 0.003; O.R. 6.37; C.I. 5.12-7.63) and early and late stroke (p = 0.02; O.R. 1.95; C.I. 1.38-2.53) and death (p = 0.0005; O.R. 2.38; C.I. 1.89-2.88) in patients with brain lesions. After 7 years, the survival rate (p = 0.0009) and stroke-free interval (p = 0.003) were lower in patients with a positive CT. After 5 years, in asymptomatic patients the survival rate (p = 0.003) and stroke-free interval (p = 0.01) were lower in the positive CT group. CONCLUSIONS A positive CT finding, regardless of congruity of the lesion, should be regarded as an indicator of an increased risk of stroke and death in patients scheduled for carotid surgery, especially in those with asymptomatic stenosis.

Angiotensin-converting enzyme gene I/D polymorphism and carotid artery disease in renovascular hypertension.

There is evidence linking the activation of the renin-angiotensin system (RAS) with target organ damage in renovascular hypertension (RVH). A genetic association of the DD genotype of the angiotensin-converting enzyme (ACE) gene with cardiovascular complications has been found in various clinical conditions. The aim of our study was to determine whether the insertion/deletion (I/D) polymorphism of the ACE gene is associated with the high prevalence of target organ damage reported in RVH. A total of 65 atherosclerotic patients (age 68.2 +/- 5.2 years) with RVH and 49 atherosclerotic patients (age 68.0 +/- 6.3 years) with essential hypertension (EH) were sequentially enrolled when attending the outpatient clinic for specialist assessment of their vascular disorder. Cardiac, renal, and vascular involvement were assessed in both groups and blood was taken for genetic analysis. Patients with RVH had a higher prevalence of left ventricular hypertrophy (LVH), carotid artery disease, and albuminuria than those with EH. In RVH, but not in EH, the DD genotype was significantly associated with severe arterial disease. In RVH, carotid disease (lumen narrowing >60%) was present in 62% of DD patients versus 25% of the other genotypes (OR = 4.90, 95% CI: 1.70-14.13). Such an association was also present in peripheral vascular disease: 72.4% in DD patients versus 41.6% in the other genotypes (OR = 3.67, 95% CI = 1.29-10.36). Logistic regression analysis showed that the DD genotype was the strongest predictor of risk of severe carotid disease. We conclude that, in atherosclerotic RVH, there is an association of the severity of vascular disease with the DD genotype of the ACE gene.

Total endovascular solution for complex visceral aneurysms

Visceral aneurysms are rare in the general population (<2%), and the most serious complication is represented by aneurysm rupture. The use of stent grafts to exclude visceral aneurysms is described in several reports but is reserved for patients with favorable anatomy. We report here on a hepatic artery pseudoaneurysm in a liver transplant patient and a patient with an aneurysmal vein graft degeneration of a renal bypass, both with no suitable proximal neck for standard stent grafting. Both patients were successfully treated with a custom-made aortic endograft with a single fenestration for the hepatic or renal artery, together with a visceral covered stent. Although initial results are promising, long-term follow-up is required to assess durability.