Pierre Maitrias

microRNAs in the pathophysiology of CKD-MBD: Biomarkers and innovative drugs.

microRNAs comprise a novel class of endogenous small non-coding RNAs that have been shown to be implicated in both vascular damage and bone pathophysiology. Chronic kidney disease-mineral bone disorder (CKD-MBD) is characterized by vessel and bone damage secondary to progressive loss of kidney function. In this review, we will describe how several microRNAs have been implicated, in recent years, in cellular and animal models of CKD-MBD, and have been very recently shown to be deregulated in patients with CKD. Particular emphasis has been placed on the endothelial-specific miR-126, a potential biomarker of endothelial dysfunction, and miR-155 and miR-223, which play a role in both vascular smooth muscle cells and osteoclasts, with an impact on the vascular calcification and osteoporosis process. Finally, as these microRNAs may constitute useful targets to prevent or treat complications of CKD-MBD, we will discuss their potential as innovative drugs, describe how they could be delivered in a timely and specific way to vessels and bone by using the most recent techniques such as nanotechnology, viral vectors or CRISPR gene targeting.

Obliterative Endoaneurysmorrhaphy with Stent Graft Preservation for Treatment of Type II Progressive Endoleak.

OBJECTIVE/BACKGROUND Persistent type II endoleak (EL II) with sac enlargement after endovascular repair of abdominal aortic aneurysm requires treatment to prevent rupture. Embolization is not always effective. Conversion to open repair with stent graft (SG) explantation is a high risk option. The aim of this study was to evaluate the feasibility and immediate results of an alternative technique combining obliterative endoaneurysmorrhaphy (OEA) with SG preservation. METHODS The open surgical technique combined sacotomy, ligation of all patent back-bleeding vessels and SG preservation. The aneurysmal shell was tightly closed over the SG to protect it from the intestines. An intra-aortic occlusion balloon was used when clamping was required. RESULTS Twelve patients were treated with the OEA technique at Amiens University Hospital. All 12 procedures were successful. Four patients had previously undergone unsuccessful transarterial or translumbar embolization. Aortic clamping was performed in four cases. No SG migration or graft dislocation was observed. Follow up computed tomography scan at a median of 12 months showed shrinkage of the aneurysm sac with stable diameters and no recurrence of EL II in all cases. CONCLUSION The OEA technique is an alternative option for the treatment of progressive EL II, which can be particularly useful after failure of embolization.

The Involvement of miRNA in Carotid-Related Stroke

Cardiovascular disease is the leading cause of morbidity and mortality in developed countries. Stroke is associated with a marked disability burden and has a major economic impact; this is especially true for carotid artery stroke. Major advances in primary and secondary prevention during the last few decades have helped to tackle this public health problem. However, better knowledge of the physiopathology of stroke and its underlying genetic mechanisms is needed to improve diagnosis and therapy. miRNAs are an important, recently identified class of post-transcriptional regulators of gene expression and are known to be involved in cerebrovascular disease. These endogenous, small, noncoding RNAs may have applications as noninvasive biomarkers and therapeutic tools in practice. Here, we review the involvement of several miRNAs in cell-based and whole-animal models of stroke, with a focus on human miRNA profiling studies of carotid artery stroke. Lastly, we describe the miRNAs’ potential role as a biomarker of stroke.

Unusual mesenteric revascularization

A 52-year-old man was referred to our department with severe chronic mesenteric ischemia. Patient consent has been obtained for publication. He had a history of heavy active smoking, hypertension, coronary heart disease, aspergillosis (A, showing sequelae of Aspergillus infection), and severe emphysema (A). Physical examination revealed postprandial pain with severe weight loss (body mass index, 14 kg/m). Computed tomography angiography (CTA) showed a coral reef aorta responsible for preocclusive lesions of the superior mesenteric and celiac arteries (B). The inferior mesenteric artery was occluded, as CTA revealed asymptomatic Leriche syndrome (B). Retrograde revascularization from the iliac arteries was not possible. We thought the patient was unlikely to survive thoracolaparotomy with transaortic endarterectomy or a thoracic aorta-to-mesenteric bypass procedure because of his history and poor general status. We finally decided to perform left axillary-to-mesenteric bypass using a 6-mm externally ringed tube graft. The patient’s postoperative recovery was marked by heart failure and pneumonia, which resolved in response to medical treatment. The patient’s abdominal symptoms rapidly resolved, and he began to gain weight. The 6-month follow-up CTA revealed a patent bypass with no anastomotic stenosis, as shown by a three-dimensional reconstruction (C/Cover).

Type II endoleak after endoluminal repair of thoracic aortic aneurysm associated with native coarctation

Aneurysm formation and recurrent coarctation are common complications of coarctation repair, and various types of treatment have been described. Native aortic coarctation during adult life is rarer and can be responsible for severe complications. We report an original case of thoracic aortic aneurysm associated with native coarctation successfully treated by a hybrid approach, comprising retrograde implantation of a thoracic stent graft and carotid-axillary bypass graft. A large intercostal collateral was embolized with coils.

Superficial Femoral Artery Transposition Repair for Traumatic Popliteal Rupture

Closed dislocation of the knee with complete popliteal rupture is an uncommon injury. It requires prompt recognition and treatment to prevent limb loss. We describe a case of acute ischemia caused by complete knee dislocation with rupture of the popliteal artery that was successfully repaired with superficial femoral artery transposition. To the best of our knowledge, this is the first reported clinical experience of the use of an arterial autograft for revascularization of traumatic popliteal artery rupture.