Screening pulmonary arteriovenous malformations in a large cohort of Spanish patients with hemorrhagic hereditary telangiectasia

39 p.-1 fig.-7 tab.Background and objectives Because of the serious nature of potential complications, screening for pulmonary arteriovenous malformations is required in patients with hereditary hemorrhagic telangiectasia. The aim of this study was to evaluate the utility of contrast echocardiography and compare the performance of two contrast agents: agitated saline and Gelofusine.Material and methods Two hundred and five patients screened for PAVMs using TTCE and computed tomography (CT) performed with an interval of less than 180 days. Contrast echocardiography studies were graded on a 4-point semiquantitative scale based on the amount of microbubbles seen in left heart chambers.Results Positive TTCE findings were seen in 137 (66.8%) patients, whereas CT confirmed PAVMs in 59 (43.1%). Two of 67 grade 1 patients; 18 of 42 grade 2; 17 of 22 grade 3 and all grade 4 had PAVMs on CT. Embolotherapy was feasible in 38.9% patients in grade 2 and 82.3% and 95.2% in grades 3–4. No patients in grade 1 were embolized. The mean cardiac cycle in which bubbles were first seen in the left heart in patients without and with PAVMs on CT was 6.1 and 3.9 (p < 0.0001). Compared to saline, Gelofusine produced an overall increase in grade.Conclusions No grade 1 patients had treatable PAVMs. There is a need for improvement in the selection of patients for CT in grade 2, where less than half have PAVMs on CT. The cardiac cycle may help to differentiate between patients with and without PAVMs. Gelofusine was not better than saline for PAVM screening.This study has been supported by grants from Instituto de Salud Carlos III (ISCIII; PI11/0246 to JAP), FEDER (to JAP), Ministerio de Economía y Competitividad of Spain (SAF2011-23475 to LMB and SAF2013-43421-R to CB), and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER; ISCIIICB06/ 07/0038 to CB).Peer reviewe

Microfluidic model of bubble lodging in microvessel bifurcations

The lodging mechanisms and dynamics of cardiovascular gas bubbles are investigated in microfluidic model bifurcations made of poly(dimethylsiloxane). This work is motivated by gas embolotherapy for the potential treatment of cancer by tumor infarction. The results show that the critical driving pressure below which a bubble will lodge in a bifurcation is significantly less than the driving pressure required to dislodge it. From the results the authors estimate that gas bubbles from embolotherapy can lodge in vessels 20 μm20μm or smaller in diameter, and conclude that bubbles may potentially be used to reduce blood flow to tumor microcirculation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87802/2/244103_1.pd

Embolisation for pulmonary arteriovenous malformation (Review)

Background: Pulmonary arteriovenous malformations are abnormal direct connections between the pulmonary artery and pulmonary vein which result in a right-to-left shunt. They are associated with substantial morbidity and mortality mainly from the effects of paradoxical emboli. Potential complications include stroke, cerebral abscess, pulmonary haemorrhage and hypoxaemia. Embolisation is an endovascular intervention based on the occlusion of the feeding arteries the pulmonary arteriovenous malformations thus eliminating the abnormal right-to-left-shunting. Objectives: To determine the efficacy and safety of embolisation in patients with pulmonary arteriovenous malformations including a comparison with surgical resection and different embolisation devices. Search methods: We searched the Cystic Fibrosis and Genetic Disorders Group's Trials Register; date of last search: 31 March 2014. We also searched the following databases: the Australian New Zealand Clinical Trials Registry; ClinicalTrials.gov; International Standard Randomised Controlled Trial Number Register; International Clinical Trials Registry Platform Search Portal (last searched 1 July 2014). We checked cross-references and searched references from review articles. Selection criteria: Trials in which individuals with pulmonary arteriovenous malformations were randomly allocated to embolisation compared to no treatment, surgical resection or embolisation using a different embolisation device. Data collection and analysis: Studies identified for potential inclusion were independently assessed for eligibility by two authors, with excluded studies further checked by a third author. No trials were identified for inclusion in the review and hence no analysis was performed. Main results: There were no randomised controlled trials included in the review; one ongoing trial has been identified which may be eligible for inclusion in the future. Authors' conclusions: There is no evidence from randomised controlled trials for embolisation of pulmonary arteriovenous malformations. However, randomised controlled trials are not always feasible on ethical grounds. Accumulated data from observational studies suggest that embolisation reduces morbidity. A standardised approach to reporting with long-term follow-up through registry studies can help to strengthen the evidence for embolisation in the absence of randomised controlled trials

Optimal management of hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia (HHT), also known by the eponym Osler–Weber–Rendu syndrome, is a group of related disorders inherited in an autosomal dominant fashion and characterized by the development of arteriovenous malformations (AVM) in the skin, mucous membranes, and/or internal organs such as brain, lungs, and liver. Its prevalence is currently estimated at one in 5,000 to 8,000. Most cases are due to mutations in the endoglin (HHT1) or ACVRLK1 (HHT2) genes. Telangiectasias in nasal and gastrointestinal mucosa generally present with recurrent/chronic bleeding and iron deficiency anemia. Larger AVMs occur in lungs (~40%–60% of affected individuals), liver (~40%–70%), brain (~10%), and spine (~1%). Due to the devastating and potentially fatal complications of some of these lesions (for example, strokes and brain abscesses with pulmonary AVMs), presymptomatic screening and treatment are of utmost importance. However, due to the rarity of this condition, many providers lack an appreciation for the whole gamut of its manifestations and complications, age-dependent penetrance, and marked intrafamilial variation. As a result, HHT remains frequently underdiagnosed and many families do not receive the appropriate screening and treatments. This article provides an overview of the clinical features of HHT, discusses the clinical and genetic diagnostic strategies, and presents an up-to-date review of literature and detailed considerations regarding screening for visceral AVMs, preventive modalities, and treatment options

A Rare Case of Jejunal Arterio-Venous Fistula: Treatment with Superselective Catheter Embolization with a Tracker-18 Catheter and Microcoils

Arterio-venous fistulas may develop spontaneously, following trauma or infection, or be iatrogenic in nature. We present a rare case of a jejunal arterio- venous fistula in a 35-year-old man with a history of pancreatic head resection that had been performed two years previously because of chronic pancreatitis. The patient was admitted with acute upper abdominal pain, vomiting and an abdominal machinery-type bruit. The diagnosis of a jejunal arterio-venous fistula was established by MR imaging. Transfemoral angiography was performed to assess the possibility of catheter embolization. The angiographic study revealed a small aneurysm of the third jejunal artery, abnormal early filling of dilated jejunal veins and marked filling of the slightly dilated portal vein (13-14 mm). We considered the presence of segmental portal hypertension. The patient was treated with coil embolization in the same angiographic session. This case report demonstrates the importance of auscultation of the abdomen in the initial clinical examination. MR imaging and color Doppler ultrasound are excellent noninvasive tools in establishing the diagnosis. The role of interventional radiological techniques in the treatment of early portal hypertension secondary to jejunal arterio-venous fistula is discussed at a time when this condition is still asymptomatic. A review of the current literature is include

Endovascular treatment of pulmonary arteriovenous malformations in hereditary haemorrhagic telangiectasia.

PRINCIPLES: To assess the efficiency and complication rates of vaso-occlusion of pulmonary arteriovenous malformations (PAVMs) in Rendu-Osler-Weber disease (hereditary haemorrhagic telangectasia; HHT). METHODS: Seventy-two patients were investigated in our institution for HHT between March 2000 and November 2011. Sixteen presented PAVMs (22.2%), and 11 (68.8%) were treated with vaso-occlusion for a total of 18 procedures. Procedures included coils, plugs and combined approaches. Immediate success and recurrence rate, complication were recorded, as well as persistent and new PAVMs during clinical and computed tomography (CT) follow-up. RESULTS: Eighteen procedures were performed and a total of 37 PAVMs were treated, 19 with coils, 16 with plugs and 2 with combined treatment. Mean CT follow-up time was 41 months (1‒164). No major complication was observed. One distal translocation was treated during the same intervention. Two PAVMs persisted after treatment (5.7%), both treated by means of plug embolisation. One new PAVM was observed during follow-up CT. PAVMs with an afferent artery of less than 3mm or asymptomatic PAVMs were not treated. CONCLUSION: Recent studies have demonstrated that vaso-occlusion has become the gold standard treatment for PAVM. This study is in accordance with previous results and shows a minimal complication rate and little recurrence, whether by coils, plugs, or combined treatments