Eugenio Rosset

Homocysteine induces synthesis of a serine elastase in arterial smooth muscle cells from multi-organ donors

OBJECTIVES In heart transplant recipients with diffuse coronary arteriopathy, we have previously demonstrated the prevalence of elevated homocysteinemia, also known as an independent risk factor for myocardial infarction and stroke. In hyperhomocysteinemic mini-pigs we also observed early detectable pathologic changes in the elastic laminae. We hypothesized that homocysteine causes premature breakdown in the arterial elastic fibers by activation of the elastolytic activities. METHODS We examined the effect of homocysteine on elastase-like production by smooth muscle cells from sub-inguinal arteries of multi-organ donors (23.4 +/- 3.4 yr, n = 8). The freshly isolated cells were incubated for 0-72 h with homocysteine (0-250 microM), in the presence or absence of specific protease inhibitors. RESULTS Homocysteine was devoid of a direct effect, but after 18 h incubation the elastase-like activities increased by 5-6-fold in the extracellular medium. The enzymes were characterized as serine proteases. Incubation of cells with a nucleic acid synthesis inhibitor (actinomycin D) or a protein synthesis inhibitor (cycloheximide) suppressed the enzyme induction. CONCLUSIONS This is the first report of serine protease induction by homocysteine in vascular smooth muscle cells. The process may require protein synthesis and account for the early alterations of the arterial elastic structures in heart transplant recipients, and in other hyperhomocysteinemic patients, as well.

Morphologic assessment of abdominal aortic aneurysms by spiral computed tomographic scanning

PURPOSE The aim of this study was to seek a relationship between the morphologic features of abdominal aortic aneurysms and the feasibility of endoaortic grafting. METHODS Between June 1995 and January 1996, 86 patients were prospectively studied with contrast-enhanced spiral computed tomographic scans, which provided 35 parameters concerning the aorta and iliac arteries. Four groups were established according to the diameter of abdominal aortic aneurysms: group A, 40 to 49 mm, 36 patients; group B, 50 to 59 mm, 26 patients; group C, 60 to 69 mm, 10 patients; and group D, greater than 70 mm, 14 patients. RESULTS There was a correlation between the diameter and length of the aneurysm (p < 0.0001) and between aneurysm diameter and length of the proximal neck (p < 0.001). Presence of a proximal neck or a distal neck was more frequent in groups A and B than in groups C and D (p < 0.01). The feasibility of endovascular grafting was estimated at between 50% and 61.6% and was higher in groups A and B than in groups C and D (p < 0.01). CONCLUSIONS This study has shown an inverse relationship between the diameter of the aneurysm and the length of the aortic neck (correlation coefficient, -0.3640, p < 0.001). The diameter of an aneurysm was the most useful of the 31 parameters measured in predicting the feasibility of endoaortic grafting, estimated at 71% for aneurysms less than 60 mm in diameter and 37.5% for aneurysms greater than 60 mm in diameter (p < 0.01).

Effects of cryopreservation on the viscoelastic properties of human arteries.

The purpose of this study was to use our newly developed mock circulation loop to determine the effects of cryopreservation on the common carotid artery (CCA) and the superficial femoral artery (SFA). Fourteen healthy arteries (7 CCA and 7 SFA) harvested from multiple organ donors between the ages of 18 and 35 years were tested before and after cryopreservation at −140° C using dimethyl sulfoxide and the vapor phase of liquid nitrogen. Mean storage time was 4.2 months. The mock pulse rate was 60 beats/min and the following four systolic/diastolic pressures settings were used: 50/110, 80/140, 110/170, and 140/200 mm Hg. Simultaneous measurements of intra-arterial pressure and external arterial diameter were made using an intra-arterial pressure sensor and external piezoelectric sensors. Measured data were used to calculate pulsatility, volumetric compliance, stiffness, midwall radial arterial stress, Youngs modulus, and the incremental modulus. After SFA cryopreservation, no significant changes were observed. Conversely, CCA cryopreservation led to a significant decrease in compliance and pulsatility and a significant increase in stiffness. Youngs modulus, the incremental modulus, and midwall radial arterial stress did not change significantly. A clearcut decrease in hysteresis was observed after cryopreservation in the CCA. No evidence of structural changes was detected on light and scanning electron microscopy. Baseline findings in this study were consistent with classification of the CCA as an elastic artery and the SFA as a muscular artery. Cryopreservation had no effect on the viscoelastic properties of muscular arteries (SFA). Cryopreservation affected only values related to the cylindrical shape of the elastic arteries (CCA). It had no effect on values related to wall structure.

Politeal artery entrapment syndrome

We report 15 examples of popliteal artery entrapment syndrome observed in 11 patients. The anatomical causes were as follows: in one case, the popliteal artery presented an aberrant course medially to the medial head of the gastrocnemius muscle. In 5 cases, there was a small fibrous band linking the medial head of the gastrocnemius muscle to the lateral condyle and crossing behind the popliteal artery; in 5 cases this anomaly was also found in association with an abnormally high and/or internal insertion of the medial head of gastrocnemius muscle. In the last 4 cases, there was a muscular insertion anomaly associated with muscular hypertrophy causing arterial compression. Arteriography performed in the 11 patients showed evocative signs of the diagnosis in all cases where the artery was patent. Two popliteal arteries were occluded. CT scan and MRI examination of the popliteal fossa enabled us to define the muscular origin of the popliteal compression. All of the patients were operated upon; two received a reversed saphenous bypass and all of the others were treated by liberation of the popliteal artery and/or vein by a posterior approach. Follow-up in all patients at long term showed good prognosis. All of the patients were able to take up their previous physical activities without sequelae. Our review of the literature, which is based on 374 cases of popliteal artery entrapment observed in 280 patients, made it possible to define the frequency of the various anomalies observed, their symptoms and the different therapeutic possibilities. The multiple anatomical classifications as well as the arterial and muscular embryology are also described.

Simultaneous Reconstruction of Infrarenal Abdominal Aorta and Renal Arteries

From 1980 to 1990, 48 (4.7%) of 1,002 patients underwent elective aortic reconstruction and simultaneous renal artery reconstruction. Forty-five men and three women (mean age: 66.5 years) had 59 renal artery lesions (51 stenoses, six occlusions, one dysplasia, and one aneurysm) associated with 20 infrarenal aortic aneurysms and 28 aortoiliac occlusive lesions. One nephrectomy and 58 renal artery reconstructions were performed (35 prosthetic bypasses, 11 vein bypasses, six direct reimplantations, five transaortic endarterectomies, and one resection of an intrahilar aneurysm followed by autotransplantation). Operation was always indicated for the aortic lesions. Indication for renal artery repair was hypertension in 33 cases (17 associated with renal insufficiency) and one with isolated renal insufficiency. In the remaining 14 cases, surgery was deemed preventive. One patient died (2%). There were 12 nonfatal complications two of which were kidney failures requiring chronic extrarenal epuration. Routine follow-up arteriograms showed four postoperative renal artery occlusions. Mean follow-up was 35.8 months. Four patients were lost to follow-up; 10 died secondarily. Five year survival was 72.1±19.1%. Secondary patency of renal artery reconstruction was 89.5±9.4% at five years. Late results were favorable in 45% of patients with hypertension and in 39% of patients with renal insufficiency. Mortality in simultaneous aortic and renal artery reconstruction is not superior to that of isolated infrarenal aortic surgery.

A multicenter experience with infected abdominal aortic endograft explantation

Objective: Endovascular aneurysm repair (EVAR) is widely used with excellent results, but its infectious complications can be devastating. In this paper, we report a multicenter experience with infected EVAR, symptoms, and options for explantation and their outcome. Methods: We have reviewed all consecutive endograft explants for infection at 11 French university centers following EVAR, defined as index EVAR, from 1998 to 2015. Diagnosis of infected aortic endograft was made on the basis of clinical findings, cultures, imaging studies, and intraoperative findings. Results: Thirty‐three patients with an infected aortic endograft were identified. In this group, at index EVAR, six patients (18%) presented with a groin or psoas infection and six patients (18%) presented with a general infection, including catheter‐related infection (n = 3), prostatitis (n = 1), cholecystitis (n = 1), and pneumonia (n = 1). After index EVAR, eight patients underwent successful inferior mesenteric artery embolization for a type II endoleak within 6 months of index EVAR and one patient received an additional stent for a type Ib endoleak 1 week after index EVAR. Median time between the first clinical signs of infection and endograft explantation was 30 days (range, 1 day to 2.2 years). The most common presenting characteristics were pain and fever in 21 patients (64%) and fever alone in 8 patients (24%). Suprarenal fixation was present in 20 of 33 endografts (60%). All patients underwent endograft explantation, with bowel resection in 12 patients (36%) presenting with an endograft‐enteric fistula. Methods of reconstruction were graft placement in situ in 30 patients and extra‐anatomic bypass in 3 patients. In situ conduits were aortic cryopreserved allografts in 23, polyester silver graft in 5, and autogenous femoral vein in 2. Microbiology specimens obtained from the endograft and the aneurysm were positive in 24 patients (74%). Gram‐positive organisms were the most commonly found in 18 patients (55%). Early mortality (30 days or in the hospital) was 39% (n = 13) in relation to graft blowout (n = 3), multiple organ failure (n = 6), colon necrosis (n = 3), and peripheral embolism (n = 1). At 1 year, the rates of patient survival, graft‐related complications, and reinfection were 44%, 10%, and 5%, respectively. Conclusions: Abdominal aortic endograft explantation for infection is high risk and associated with graft‐enteric fistula in one‐third of the cases. Larger multicenter studies are needed to better understand the risk factors and to improve preventive measures at index EVAR and during follow‐up.

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.

Predictive Factors for Type II Endoleaks after Treatment of Abdominal Aortic Aneurysm by Conventional Endovascular Aneurysm Repair.

BACKGROUND The aim of this study was to identify the predictive factors for the development of type II endoleaks (EL-II) after endovascular aneurysm repair (EVAR). METHODS We assessed the preoperative and postoperative computed tomography data of 308 patients who underwent EVAR between 2000 and 2012 and in 84 of whom primary or secondary EL-II occurred. The data analyzed were: demographics, number and diameter of lumbar arteries (LAs), inferior mesenteric artery (IMA), median sacral artery (MSA), accessory renal arteries (ARas), maximum diameter of infrarenal abdominal aortic aneurysm, diameter and length of proximal aortic neck. Statistical analysis was performed using Stata software (version 12). Categorical parameters were compared between groups using chi-squared or Fishers exact tests as appropriate. Continuous variables were analyzed using Students t-test or Mann-Whitney test as appropriate (normality studied by the Shapiro-Wilk and homoscedasticity verified using the Fisher-Snedecor test). RESULTS Of the 308 patients included (mean age, 73.8 ± 8.74 years), 284 (92%) were men, 61 (20%) were smokers, 113 (37%) had chronic obstructive pulmonary disease, 215 (70%) were taking antiplatelet. Respectively, 13, 51, 60, 103, 28, 40, 2, and 7 patients had 1, 2, 3, 4, 5, 6, 7, and 8 patent LAs. Before surgery, 221 IMAs and 136 MSA were patent. The sources of EL-II were: LA (n = 51), IMA (n = 22), MSA (n = 1), IMA and LA (n = 8), IMA and ARa (n = 1), and unknown (n = 1). Logistic regression models adjusting for clinically relevant covariables (age, American Society of Anesthesiologists, smoking status, dyslipidemia, and diuretics) were proposed to study morphologic EL-II predictive factors, first in the entire population, and then in the more specific population for whom IMA was patent. Risk factors of occurrence EL-II were: permeability of the IMA (70 patients [83%] vs. 155 [69%], P = 0.01), IMA diameter (3.49 mm vs. 2.71 mm, P < 0.001), number of LAs patent higher than or equal to 4 (P < 0.001), the mean LA diameter greater than 2.4 mm (P < 0.001), and MSA diameter (2.28 mm vs. 1.94 mm; P < 0.01). CONCLUSIONS Our results show the major role of the number and diameter of the patent aortic branches in the development of EL-II. As they can result in complications increasing the morbidity and mortality after EVAR, it is relevant to identify the risk factors of their occurrence.

Value of Angioscopy for Intraoperative Assessment of Carotid Endarterectomy

From March 1992 to November 1993 we used angioscopy and arteriography for intraoperative assessment of 103 carotid endarterectomies in 96 patients. The indication for surgery was asymptomatic stenosis in 55 cases and neurologic and/or ocular symptoms in 48. Intraoperative angioscopy and arteriography were performed to allow comparison of findings. Intraoperative angioscopic images were normal in 67 cases and abnormal in 36. The defect was an intimal flap in 26 cases, detachment of the distal plaque in seven cases, and an intimal wedge in five cases. In two cases both detachment and a wedge were observed. The defect was not considered severe enough to warrant revision in 31 cases and was corrected in five cases by either vein bypass (n = 1) or revision of the endarterectomy (n = 4). In the latter four cases repeat angioscopy showed normal findings. Arteriographic and angioscopic findings were compared in 102 cases. In the 71 cases in which angioscopic findings were normal, arteriography revealed a major abnormality in three cases: kinking in one and stenosis > 40% in two. Kinking was treated by attachment of the common carotid artery and stenosis by venous bypass. In the 31 cases in which angioscopy revealed defects not considered to warrant revision, arteriography revealed stenosis > 40% in three cases treated by either prosthetic bypass (n = 2) or revision of the endarterectomy (n = 1). The false negative rate for angioscopy was 5.9% and concordance between the two methods was 94.1%. The combined mortality-morbidity rate was 1.9% (one stroke and one death). Postoperative evaluation of anatomic findings by arteriography or Doppler ultrasonography revealed asymptomatic internal carotid occlusion in one and internal carotid stenosis < 30% in four cases. Angioscopy is a simple, low-cost method in intraoperative control that can be used either as an adjunct to arteriography or as an alternative if arteriography cannot be performed.

Internal carotid artery surgery: ten-year results.

The twofold purpose of this study was to compare the immediate results of surgery for lesions of the internal carotid artery in two series of patients operated on at 10-year intervals and to assess long-term results in the earliest series. Series I comprised 242 reconstructions in 220 patients (160 men and 60 women, mean age 64.4 years) performed between 1980 and 1982. Seventy patients (35%) were asymptomatic, 113 had monocular or hemispheric symptoms, and 30 had nonhemispheric symptoms. Contrast arteriograms revealed internal carotid artery stenosis of <30% in 74 cases (30.6%), between 30% and 70% in 49 (20.2%), and >70% in 119 (49.2%). Reconstruction was achieved by endarterectomy in 164 cases (67.8%), by vein graft in 75 cases (31%), and by other methods in 3 cases (1.2%). Postoperative mortality was 5% (11/110). Nonfatal postoperative stroke occurred in 1.8% (4/220) and transient ischemic attack in 0.5% (1 patient). All reconstructions were patent on postoperative control. The combined mortality/morbidity rate in patients in series II operated on between 1990 and 1991 was significantly lower, that is, 2.4% (4/170) vs. 6.8% (15/220) (p < 0.05). In series I, 11 patients (5%) were lost to follow-up and 124 were still alive at the beginning of the tenth postoperative year. Cumulative survival was 79 ± 5.6% at 5 years and 60.9 ± 6.7% at 10 years. The causes of late death were stroke in 7 cases, cardiovascular disease in 30 cases; cancer in 16 cases, and other causes in 20 cases. The patency rate, including occlusion and restenosis, was 95.3 ± 3% at 5 years and 90.1 ± 4.6% at 10 years. Neurologio events occurred during follow-up in 32 patients, including ipsilateral stroke in 13 cases and contralateral stroke in 5 cases. The stroke-free rate was 89 ± 4.3% at 5 years and 84.8 ± 5.2% at 10 years.