Franco Grego

Number and Function of Endothelial Progenitor Cells as a Marker of Severity for Diabetic Vasculopathy

Objective—Peripheral arterial disease (PAD) is a threatening complication of diabetes. As endothelial progenitor cells (EPCs) are involved in neovasculogenesis and maintenance of vascular homeostasis, their impairment may have a role in the pathogenesis of diabetic vasculopathy. This study aimed to establish whether number and function of EPCs correlate with PAD severity in type 2 diabetic patients. Methods and Results—EPCs were defined by the expression of CD34, CD133 and KDR, and quantified by flow cytometry in 127 diabetic patients with and without PAD. PAD severity has been assessed as carotid atherosclerosis and clinical stage of leg atherosclerosis obliterans. Diabetic patients with PAD displayed a significant 53% reduction in circulating EPCs versus non-PAD patients, and EPC levels were negatively correlated with the degree of carotid stenosis and the stage of leg claudication. Moreover, the clonogenic and adhesion capacity of cultured EPCs were significantly lower in diabetic patients with PAD versus patients without. Conclusions—This study demonstrates that EPC decrease is related to PAD severity and that EPC function is altered in diabetic subjects with PAD, strengthening the pathogenetic role of EPC dysregulation in diabetic vasculopathy. EPC count may be considered a novel biological marker of peripheral atherosclerosis in diabetes.

Widespread Increase in Myeloid Calcifying Cells Contributes to Ectopic Vascular Calcification in Type 2 Diabetes

Rationale: Acquisition of a procalcific phenotype by resident or circulating cells is important for calcification of atherosclerotic plaques, which is common in diabetes. Objective: We aim to identify and characterize circulating calcifying cells, and to delineate a pathophysiological role for these cells in type 2 diabetes. Methods and Results: We demonstrate for the first time that a distinct subpopulation of circulating cells expressing osteocalcin and bone alkaline phosphatase (OC+BAP+) has procalcific activity in vitro and in vivo. The study of naïve patients with chronic myeloid leukemia indicated that OC+BAP+ cells have a myeloid origin. Myeloid calcifying OC+BAP+ cells (MCCs) could be differentiated from peripheral blood mononuclear cells, and generation of MCCs was closely associated with expression of the osteogenic transcription factor Runx2. In gender-mismatched bone marrow–transplanted humans, circulating MCCs had a much longer half-life compared with OC−BAP− cells, suggesting they belong to a stable cell repertoire. The percentage of MCCs was higher in peripheral blood and bone marrow of type 2 diabetic patients compared with controls but was lowered toward normal levels by optimization of glycemic control. Furthermore, diabetic carotid endoarterectomy specimens showed higher degree of calcification and amounts of cells expressing OC and BAP in the &agr;-smooth muscle actin–negative areas surrounding calcified nodules, where CD68+ macrophages colocalize. High glucose increased calcification by MCCs in vitro, and hypoxia may regulate MCC generation in vitro and in vivo. Conclusions: These data identify a novel type of blood-derived procalcific cells potentially involved in atherosclerotic calcification of diabetic patients.

Visceral artery aneurysms: a single center experience.

BACKGROUND Splanchnic artery areurysm is a rare but clinically relevant disease, showing a high mortality rate in emergency surgery. Reports on splanchnic aneurysms are rare and often anecdotal. The aim of this study is to discuss data obtained from 16 patients in a single vascular surgery center. MATERIALS AND METHODS Between January 1987 and December 2000, 16 patients underwent surgery for splanchnic artery aneurysms. In 13 patients the localization was single (in two associated with an infrarenal abdominal aortic aneurysm) and in 3 patients multiple. The arteries involved were: splenic (8), hepatic (4), celiac (3), superior mesenteric (3), ileocolic (2), and pancreatoduodenal (1). 13 patients were asymptomatic and 3 presentec with abdominal pain. All patients underwent CT scan, and abdominal aortic and selective visceral artery angiography. Before surgery, all patients underwent cerebral MR or cerebral CT scan. 13 patients underwent open vascular surgery; 3 patients (2 splenic and 1 hepatic) underwent endovascular procedure (angioembolization). Histological examination of the aneurysmal wall was obtained in 14 patients. Ultrasound examination was performed after 6 months, then yearly. 14 patients underwent abdominal CT scan during the long-term follow-up. RESULTS Perioperative mortality was absent. 12 cases were classified as displastic, with minor or major secondary atherosclerotic changes, and in many cases severe calcications. 2 cases were classified as atherosclerotic. Cerebral MR did not show any cases of intracerebral displastric aneurismal disease. One patient was lost at follow-up after 9 years. One patient showed a recurrence at 6 years (superior mesenteric artery): the patient underwent a new surgical procedure and died 20 days after surgery for intestinal infarction. All abdominal follow-up CT scans show good results of the vascular reconstruction and escluded other new visceral or aortic aneurysms. CONCLUSIONS Visceral artery aneurysms are an uncommon form of abdominal vascular disease showing a high postoperative mortality rate in emergencies. Surgery, and in selected cases, endovascular treatment, can successfully manage splanchnic artery aneurysms with few complications and low recurrence.

Atorvastatin Reduces Macrophage Accumulation in Atherosclerotic Plaques A Comparison of a Nonstatin-Based Regimen in Patients Undergoing Carotid Endarterectomy

Background and Purpose— The object of our study was to compare the effect of high-dose vs low-dose atorvastatin vs nonstatin-based treatment (cholestyramine plus sitosterol) on cell composition of carotid plaque. Methods— We recruited 60 hypercholesterolemic patients (total cholesterol, 5.83-7.64 mmol/L) eligible for carotid endarterectomy. Three months before surgery, patients were randomized into 3 groups (n=20) receiving atorvastatin 10 mg/day (AT-10) or atorvastatin 80 mg/day (AT-80) or cholestyramine 8 g/day plus sitosterol 2.5 g/day. Analysis of cell composition was performed on endarterectomy specimens. Results— The 3 treatments resulted in a significant reduction of total cholesterol and low-density lipoprotein cholesterol (LDL-C), although the decrease in total cholesterol and LDL-C was of smaller magnitude in the cholestyramine plus sitosterol group. The 3 regimens did not influence the levels of inflammatory markers (including high-sensitivity C-reactive protein). Macrophage content was significantly lower in the AT-10 group plaques compared to the cholestyramine plus sitosterol group. It was further reduced in the AT-80 group plaques. These differences were no longer significant after adjustment for changes in LDL-C. No difference in lymphocyte number was observed among treatments, whereas the content of smooth muscle cells was higher in the AT- 80 group. An inverse association was observed between LDL-C changes in the 3 groups and macrophage content in the plaques. Conclusions— Short-term treatment with high-dose statin is superior to a nonstatin lipid-lowering regimen in reducing the macrophage cell content within atherosclerotic lesions, but this effect was determined by the degree of LDL-C-lowering.

Prospective, randomized study of external jugular vein patch versus polytetrafluoroethylene patch during carotid endarterectomy: perioperative and long-term results

OBJECTIVES The purpose of this study was to evaluate the relative risks and advantages of using external jugular vein (EJV) patch, compared with polytetrafluoroethylene (PTFE) patch, during carotid endarterectomy. The primary end point was the relevant neurologic complication rate (RNCR; fatal or disabling stroke) at any time during follow-up. Secondary end points included stroke-free survival, 30-day and long-term mortality, recurrent stenosis rate (> or =50%), occlusion, patch infection, aneurysm formation, and other local complications. METHODS The study, a prospective randomized clinical trial carried out at a single center, was divided into two 3-year phases: December 1996 to March 1999, when patients were enrolled, and March 1999 to March 2002, which was the follow-up period. Inclusion criteria included an external jugular vein suitable for patching, defined as vein diameter 3 mm or larger and absence of collateral vessels noted on preoperative color duplex ultrasound scans. Patients were prospectively randomized 1:1 to receive either the EJV (n = 80; group A) or synthetic (n = 80; group B) patch. RESULTS Carotid endarterectomy and patching was performed by one surgeon. At 30 months the RNCR-free rate, analyzed with the Kaplan-Meier method, was 98.7% for group A (1 ipsilateral lethal stroke) and 94.6% for group B (4 ipsilateral disabling strokes), and remained stable to 60 months. No statistical difference was observed with the log-rank test. Stroke-free survival rate was 100% for group A and 98.7% for group B at 1 year, 98.7% for group A and 93.6% for group B (1 ipsilateral minor stroke) at 30 months, and was unchanged at 60 months. Life table analysis demonstrated freedom from significant recurrent stenosis (> or =50%) of 97.5% for both groups at 6 months, 93.6% for group A and 92.2% for group B at 30 months, and 90.2% for group A and 86.7% for group B at 60 months. No statistical difference was observed with the log-rank test. In no patients was recurrent stenosis greater than 70%. No aneurysm formation was noted during follow-up. CONCLUSIONS We can conclude, with the power limitation of the study, that carotid endarterectomy can be safely performed with either the EJV or PTFE patch. Advantages of the EJV for carotid angioplasty include no cost for material, low risk for graft infection, and preservation of the saphenous vein.

Specific Cellular Features of Atheroma Associated With Development of Neointima After Carotid Endarterectomy The Carotid Atherosclerosis and Restenosis Study

BACKGROUND The purpose of this study was to investigate whether some cellular and molecular features of tissue retrieved at carotid endarterectomy are associated with the extent of neointima formation at ultrasound follow-up. METHODS AND RESULTS One hundred fifty patients were studied. Endarterectomy specimens were tested by immunocytochemistry with the use of (1) monoclonal antibodies that identify smooth muscle cells (SMCs) and fetal-type SMCs on the basis of smooth muscle and nonmuscle myosin content, (2) the anti-macrophage HAM 56, and (3) the anti-lymphocyte CD45RO. The maximum intima-media thickness (M-IMT) of the revascularized vessel was assessed by the use of B-mode ultrasonography 6 months after surgery. The M-IMT values were related positively to the number of SMCs (r=0.534, P<0.0005) and negatively to that of macrophages and lymphocytes (r=-0.428, P<0.0005, and -0.538, P=0.001, respectively). Patients were classified as class 1 (M-IMT </=1.0 mm), class 2 (1. 01.3 mm). An abundance of SMCs, mostly of fetal type, was found in the plaque of class 3 patients, whereas lesions from class 1 patients were rich in macrophages and lymphocytes. In the multivariate analysis, factors related to M-IMT were the number of SMCs and the percentage of fetal-type SMCs present in the plaque. CONCLUSIONS Although the classic risk factors did not play a role, an abundance of SMCs and a scarcity of macrophages characterized the primary lesion of patients in whom neointima developed after surgery. In patients in whom neointima did not develop, lesions were rich in macrophages and lymphocytes. This approach can be useful in defining patients at risk of restenosis.

Synchronous carotid endarterectomy and retrograde endovascular treatment of brachiocephalic or common carotid artery stenosis.

OBJECTIVES To retrospectively evaluate the safety and the long-term results of retrograde brachiocephalic and common carotid angioplasty and stenting (AS) performed for >70% stenosis synchronously with the carotid endarterectomy (CEA). PATIENTS Sixteen patients operated between April 1999 and March 2002. RESULTS 14/16 procedures were successful. There was no neurological morbidity or mortality. Per-operative angiography showed the optimal stent positioning and patency of both proximal and distal arteries in all patients. In the follow-up, all patients showed patency of the treated vessels without restenosis and the absence of any cerebrovascular symptoms. CONCLUSION Intra-operative retrograde AS combined with CEA is an effective, safe and durable alternative to conventional surgery when a tandem significant proximal lesion is identified in a patient with an high grade carotid stenosis.

Hybrid endovascular treatment of aneurysm degeneration in a rare right-aortic arch anomaly with Kommerell diverticulum

We present a hybrid endovascular approach to a 6.5-cm aneurysm of the right-sided aortic arch with an aberrant left subclavian artery arising from a Kommerell diverticulum, connected to the left pulmonary artery through the ligamentum arteriosum. The two-step procedure consisted of a bilateral carotid-subclavian bypass, followed by an ascending aorta-bicarotid bypass and completed by an endovascular exclusion of the aneurysms by covering the whole aortic arch and its branches. The patient had no complications and is asymptomatic 21 months after surgery. Hybrid procedures may be helpful in complex aortic arch pathologies, reducing complications of challenging open surgery.

Paraganglioma syndrome: SDHB, SDHC, and SDHD mutations in head and neck paragangliomas.

Abstract:  Paraganglioma syndrome includes head and neck paraganglioma and pheochromocytoma, and is classified according to the three susceptibility genes involved, SDHB, SDHC, and SDHD. This study assessed the prevalence of germline mutations in SDHB, SDHC, and SDHD genes in a consecutive population admitted to Padova Hospital consisting of 20 patients with head and neck paraganglioma (HNP). Mutations were identified in the three genes in four affected individuals, three sporadic cases and one with family history of HNP. The novel SDHB p.R242C mutation was identified in a sporadic monolateral carotid body tumor. The SDHC p.Q147X mutation, the first to be described in Italy, was detected in a sporadic monolateral jugulotympanic paraganglioma. The SDHD p.Y114C mutation was identified in two unrelated patients, one familial case of bilateral carotid body tumor and one multiple paraganglioma. SDHB, SDHC, and SDHD molecular screening is important in all HNPs, with or without primary indicators of paraganglioma syndrome, to orient mutation‐driven clinical screening for additional HNPs and pheochromocytoma.

Outcomes of endovascular aneurysm repair on renal function compared with open repair

OBJECTIVE Recent studies have shown that progressive renal dysfunction may develop in patients after endovascular aneurysm repair (EVAR). Data are conflicting about the effect of EVAR on renal function compared with open repair (OR). The purpose of this study was to compare the effects of EVAR, both with transrenal fixation (TRF) and infrarenal fixation (IRF), vs OR on renal function detected with renal perfusion scintigraphy (RPS). METHODS A prospective study was carried out from January 2003 to December 2007. Exclusion criteria included factors that could influence post-procedural renal function as: preoperative creatinine clearance level <65 mL/min for men and 60 mL/min for women, renal artery stenosis >60%, renal accessory artery planned to be covered by the endograft, single functioning kidney, hemodialysis, and kidney transplant. To evaluate renal function, an RPS was performed preoperatively, at 30 days, at 6 and 12 months, and then yearly. The glomerular filtration rate (GFR) was estimated with the Gates method. RESULTS During the study period, 403 patients were enrolled; 243 (60%) had OR and 160 (40%) EVAR; among these, 83 (51%) had a TRF and 77 (48%) an IRF; 55 patients were excluded from the study. No statistical differences were observed between groups for demographics and risk factors. Statistically significant differences emerged between OR and EVAR for early postoperative death (4% vs 0%; P = .01). Follow-up ranged from 54 to 126 months (mean, 76 months) for OR and from 54 to 124 months (mean, 74 months) for EVAR (P = NS). Kaplan-Meier analysis survival rate at 9 years was 70% for OR and 58% for EVAR with a risk of secondary procedure of 9% and 34%, respectively (P < .0001). A deterioration of the GFR was observed during the follow-up in both groups with a decrease after 9 years of 11% in the EVAR group and 3% in the OR group respective to baseline (P < .001). A remarkable difference emerged on renal function between EVAR patients who required a secondary procedure compared with the other EVAR patients (P < .005). No significant differences emerged between TFR and IRF for GFR decline during the follow-up period. CONCLUSIONS After EVAR, there is a continuous decline in renal function with respect to OR, regardless of fixation level and independently of pre-existing renal insufficiency. The risk of GFR impairment after EVAR should be taken into consideration in selecting patients with preoperative renal insufficiency.