Diagnosis of Celiac Artery In‐Stent Thrombosis by Transesophageal Echocardiography

We present a case of a 70‐year‐old woman with severe peripheral arterial disease presenting with celiac artery in‐stent thrombosis diagnosed by transesophageal echocardiography (TEE). Routine assessment of the visceral arteries is not performed in most TEE studies. A review of the literature shows that the celiac and superior mesenteric arteries can be successfully visualized during transgastric views of the abdominal aorta. We propose that two‐dimensional and color Doppler echocardiography have several intrinsic advantages over computed tomography, magnetic resonance angiography and catheterization when assessing aortic and visceral arterial pathology.     

An Unusual Cause of Dyspnea

Background. Right-sided arcus aorta (RSAA) is a rare condition and usually asymptomatic. However, it may be symptomatic if it causes tracheal or esophageal compression. Methods. The authors evaluated clinical and radiological features of seven patients with RSAA who had the diagnosis between May 2006 and May 2009. Results. The authors found that the incidence of RSAA was 0.16% in patients who had applied to their clinic. The age of patients ranged from 17 to 55 years. The male to female ratio was 6/1. Four patients were symptomatic due to RSAA. Most common symptoms were dyspnea during exercise, which is similar to exercise-induced asthma and dysphagia. Two patients were misdiagnosed as asthma. The flow-volume curves on spirometry of the patients showed intrathoracic upper airway obstruction. Thorax magnetic resonance imaging (MRI) revealed marked narrowing of the tracheal air column due to external compression of RSAA in three patients. Conclusions. RSAA should be included in the differential diagnosis of asthma. Spirometry may help to suspect RSAA. Thorax computed tomography (CT) and/or MRI are the best imaging methods for the diagnosis of RSAA.     

New insights into the mechanisms of the vasorelaxant effects of apocynin in rat thoracic aorta

Apocynin is a naturally occurring acetophenone widely used as an inhibitor of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Recent data suggested that apocynin might exert NADPH oxidase‐independent pharmacological properties. Among them, vasorelaxant properties have been described, but the mechanisms still give rise to debates. The present study investigated the mechanisms involved in the vasorelaxant effect of apocynin on the in vitro model of rat isolated thoracic aortic rings. Apocynin (30 μm to 10 mm ) induced a dose‐dependent relaxation in both endothelium‐intact and endothelium‐denuded aortic rings with respective EC₅₀ values of 0.78 ± 0.08 and 1.91 ± 0.21 mm . Endothelium removal or inhibition of nitric oxide (NO) synthase with N^ω‐nitro‐l ‐arginine‐methyl ester (l ‐NAME) significantly decreased but did not abolish the effect of apocynin. By contrast, apocynin‐induced relaxation was unchanged after incubation with indomethacin or charybdotoxin plus apamin. In endothelium‐denuded aortas, the vasorelaxant effect of apocynin was significantly reduced by glibenclamide but not by 4‐aminopyridine nor by iberiotoxin. Apocynin significantly decreased Ca²⁺‐induced contraction and inhibited intracellular Ca²⁺mobilization after contraction with phenylephrine. Finally, the acute intravenous injection of apocynin led to an immediate and transient hypotensive effect in spontaneously hypertensive rats (SHR). In conclusion, our data demonstrated that apocynin induces both endothelium‐independent relaxant effects involving inhibition of Ca²⁺mobilization and activation of K_ATP channels in vascular smooth muscle cells and endothelium‐dependent effects mediated by NO. These results should provide a basis for caution when interpreting results on the vascular effects of apocynin.     

Oesophageal echocardiography

Summary The diagnostic value of oesophageal echocardiography is most striking in patients in whom precordial studies are of inadequate quality or fail to establish a definitive diagnosis. Oesophageal studies have excellent image quality, can be completed within 10 minutes without complications and, in most instances, enables the clinical question to be answered. In 50 patients referred for suspected thoracic aorta pathology, oesophageal echocardiography correctly excluded or diagnosed the type of aortic dissection, aortic aneurysm or the site of coarctation. Of 35 patients referred with suspected infective endocarditis, oesophageal echocardiography revealed complications in 18 patients, including vegetation, mycotic aneurysm, abscess or chordal rupture. Oesophageal echocardiography is extremely helpful to visualize intracardiac mass lesions. In 27 patients with a history of systemic or pulmonary embolism, the technique confirmed the presence, size and position of a mass lesion in 11 patients. Oesophageal color Doppler flow imaging further expands the diagnostic capabilities, particularly in patients with mitral valve prosthesis. Our experience indicates that oesophageal echocardiography significantly extends the diagnostic potential of echocardiography. Detailed knowledge of cardiothoracic anatomy and its pathologic sequelae is, however, a prerequisite for the efficient and safe application of this method.     

Accumulation of lipid in muscular arteries of short-term diabetic rats

Summary Lipid accumulation in muscular (pulmonary, coronary and tibial) arteries and elastic (aorta and pulmonary) arteries of streptozotocin diabetic (65 mg/kg) rats was studied with an electron microscope. Arterial tissue specimens taken 4 days after the induction of diabetes showed lipid deposits in smooth muscle cells in the muscular arteries of 9 out of 24 diabetic rats, but in none of the 17 control rats. Histochemically the lipid was identified as triacylglycerol. Lipid accumulation was not seen in the elastic arteries of either diabetic or control rats. The diabetic animals with lipid deposits had slightly but significantly higher plasma glucose concentrations (p<0.02), higher non-esterified fatty acids levels (p<0.01), and lower concentrations of plasma insulin (p<0.02) than those without arterial deposits. The amount of lipid deposited in the arteries was closely related to the plasma non-esterified fatty acid level, which was in the ranges 0.8–1.1 mmol/l in diabetic rats without deposits, and 1.1–2.4 mmol/l in those with deposits. The findings suggest that lipid accumulation in smooth muscle cells of muscular arteries during acute diabetes could result from the high plasma non-esterified fatty acid concentrations.     

Dépistage opportuniste de l’anévrysme de l’aorte abdominale lors de l’échocardiographie chez le patient coronarien : utile ou futile ?

Abdominal aortic aneurysm is a chronic degenerative disease that is usually silent until rupture occurs and this complication is still associated in contemporary era with a high rate of mortality. Screening programmes for abdominal aortic aneurysm have been shown to be effective in reducing global mortality in the screened population but these programmes are poorly implemented in the Western countries. As coronary artery disease and abdominal aorta aneurysmal disease share many risk factors, the cardiologist is centrally positioned in the screening strategy, not only to identify patients with higher risk of developing abdominal aortic aneurysm, but also to perform an opportunistic screening during echocardiography. This paper summarises evidence about the feasibility, indications, modalities, benefits and risks related to the opportunistic screening for abdominal aortic aneurysm during echocardiography with a particular emphasis on the population of patients with coronary artery disease.     

Comparison of the effects of inhibitors of aldose reductase and sorbitol dehydrogenase on neurovascular function, nerve conduction and tissue polyol pathway metabolites in streptozotocin-diabetic rats

Summary Aldose reductase inhibitors (ARIs) attenuate diabetic complications in several tissues, including lens, retina, kidney, blood vessels, striated muscle and peripheral nerve. However, it is unclear whether their action in diabetes mellitus depends directly on inhibiting the conversion of glucose to sorbitol by aldose reductase or indirectly by reducing the sorbitol available for subsequent metabolism to fructose by sorbitol dehydrogenase. To identify the polyol pathway step most relevant to complications, particularly neuropathy, we compared the biochemical effects of a sorbitol dehydrogenase inhibitor, WAY-135 706, (250 mg · kg⁻¹· day⁻¹) and an ARI, WAY-121 509, (10 mg · kg⁻¹· day⁻¹) on a variety of tissues, and their effects on nerve perfusion and conduction velocity. After 6 weeks of untreated streptozotocin diabetes, rats were treated for 2 weeks. Sorbitol was elevated 2.1–32.6-fold by diabetes in lens, retina, kidney, aorta, diaphragm, erythrocytes and sciatic nerve; this was further increased (1.6–8.2-fold) by WAY-135 706 whereas WAY-121 509 caused a marked reduction. Fructose 1.6–8.0-fold elevated by diabetes in tissues other than diaphragm, was reduced by WAY-135 706 and WAY-121 509, except in the kidney. Motor and sensory nerve conduction velocities were decreased by 20.2 and 13.9 %, respectively with diabetes. These deficits were corrected by WAY-121 509, but WAY-135 706 was completely ineffective. A 48.6 % diabetes-induced deficit in sciatic nutritive endoneurial blood flow was corrected by WAY-121 509, but was unaltered by WAY-135 706. Thus, despite profound sorbitol dehydrogenase inhibition, WAY-135 706 had no beneficial effect on nerve function. The data demonstrate that aldose reductase activity, the first step in the polyol pathway, makes a markedly greater contribution to the aetiology of diabetic neurovascular and neurological dysfunction than does the second step involving sorbitol dehydrogenase. [Diabetologia (1997) 40: 271–281] Received: 13 August 1996 and in final revised form: 6 December 1996     

国产覆膜支架治疗Stanford B型主动脉夹层

目的评价国产主动脉覆膜支架治疗Stanford B型主动脉夹层患者的院内及中期临床疗效。方法应用国产覆膜支架行主动脉腔内隔绝术治疗B型主动脉夹层患者34例,经股动脉置入覆膜支架封堵胸主动脉破裂口,置入Aegis或Hercules国产支架后,造影检查证实疗效。术后平均随访(19±17)个月。结果34例手术均获成功。32例置入1枚支架,2例分别置入主体和短支架各1枚,平均支架直径(33.5±3.5)mm,平均支架长度(96.5±17.6)mm。1例术后2h死于夹层破裂。3例术后存在原发性内漏。2例肾功能不全。出院后随访,2例分别于术后5个月和9个月发生继发性内漏,1例1年时升主动脉再次发现夹层,1例6个月后发生截瘫,2例死亡。结论国产主动脉覆膜支架治疗Stanford B型主动脉夹层患者具有良好的临床疗效。