Masayuki Nakayama, Takeshi Nawa, Tatsuya Chonan, Katsuyuki Endo, Satoshi Morikawa, Masashi Bando, Yasuhiko Wada, Takanobu Shioya, Yukihiko Sugiyama, Shimao Fukai
Prevalence of pulmonary arteriovenous malformations as estimated by low-dose thoracic CT screening.
Intern Med. 2012;51(13):1677-81. Epub 2012 Jul 1.
Abstract/Text
BACKGROUND: Pulmonary arteriovenous malformations (PAVMs) are rarely encountered in clinical practice. The prevalence of PAVMs associated with hereditary hemorrhagic telangiectasia (HHT) has been estimated based on the rate in the family members of HHT patients, but the prevalence of PAVMs in the general population remains unknown.
METHODS: We retrospectively examined the prevalence and clinical characteristics of PAVMs as detected by a low-dose thoracic CT screening program for lung cancer at the Hitachi Medical Center and the Hitachi General Health Care Center in the northern part of Ibaraki Prefecture, Japan.
RESULTS: From 2001 to 2007, we identified eight patients (seven females and one male) with PAVMs among 21,235 initial screening participants (the mean age of the patients with PAVMs and that of the screening participants was 60.6 years). The prevalence of PAVMs was estimated at 38 per 100,000 individuals [95% confidence interval (CI)=18-76]. The diameter of the PAVMs was a mean of 6.6 mm, and none of the lesions could be detected by chest X-ray. Females older than 60 years tended to have larger PAVMs than younger women did (p=0.06). Two patients (25%) were diagnosed with HHT. One patient had previously undergone surgery for a brain abscess.
CONCLUSION: PAVMs are more prevalent than previously reported, especially among females.
R I White, J S Pollak, J A Wirth
Pulmonary arteriovenous malformations: diagnosis and transcatheter embolotherapy.
J Vasc Interv Radiol. 1996 Nov-Dec;7(6):787-804.
Abstract/Text
The recent long-term studies from England, France, and the Netherlands, as well as our own, indicate that transcatheter embolotherapy is definitive treatment for PAVM. More recently, Puskas et al have questioned transcatheter embolotherapy as a primary treatment for patients with PAVM (4,56). Their opinion was based on two recurrences among five patients treated with transcatheter embolotherapy. It is not clear why one of the late recurrences in the series by Puskas et al happened, and the other recurrence could have been dut to early deflation of the balloon. Nevertheless, we believe that the collective experience in the larger series reporting on transcatheter embolotherapy of PAVM supports the use of embolotherapy as a primary modality of treatment. Because many patients have bilateral pulmonary malformations and many pulmonary malformations will grow with time, repeated surgical intervention is not ideal therapy. The recurrence rate of 8% reported by Remy et al using coils, and 2% reported by Pollak et al using balloons and coils supports our contention that transcatheter embolotherapy is durable and should be the initial treatment. Also, recurrences are easily retreated by transcatheter embolotherapy with durable results (54). We favor detachable balloons over coils for occluding PAVMs because immediate cross-sectional occlusion of the segmental artery is obtained in a position that preserves the most normal branches. The necessity for repeated introduction of coils, when using the coil method, contributes to longer procedure times with an increased risk of air introduction and, in our experience, a greater risk of postprocedure pleurisy. At the same time, we appreciate that approximately 70% of PAVMs can be occluded equally well with balloons or coils. We also believe that coils have unique advantages over balloons in specific anatomic situations including oversized arteries (where coils are the only option) and for occlusion of the aneurysm of a PAVM. As with all forms of embolotherapy, the interventionalist is best served by having more than one option of treatment, which for PAVM includes both balloons and coils. In summary, PAVMs are effectively managed by means of transcatheter embolotherapy. This therapy has been demonstrated to be safe and durable. Careful technique with modifications depending on the angioarchitecture of the PAVM is required. Patients with PAVMs require follow-up at 1 month and 1 year. While observations documenting serial growth of small PAVMs are somewhat limited, there is published evidence to support their growth with time (35,36). Because of these reports and our unpublished observations, we believe that patients with treated PAVM need long-term follow-up every 5 years to detect growth of small PAVMs that will ultimately reach a size where they may cause paradoxical embolization and stroke (1).
Claire L Shovlin, Robin Condliffe, James W Donaldson, David G Kiely, Stephen J Wort, British Thoracic Society
British Thoracic Society Clinical Statement on Pulmonary Arteriovenous Malformations.
Thorax. 2017 Dec;72(12):1154-1163. doi: 10.1136/thoraxjnl-2017-210764.
Abstract/Text
Pulmonary arteriovenous malformations (PAVMs) are structurally abnormal vascular communications that provide a continuous right-to-left shunt between pulmonary arteries and veins. Their importance stems from the risks they pose (>1 in 4 patients will have a paradoxical embolic stroke, abscess or myocardial infarction while life-threatening haemorrhage affects 1 in 100 women in pregnancy), opportunities for risk prevention, surprisingly high prevalence and under-appreciation, thus representing a challenging condition for practising healthcare professionals. The driver for the current Clinical Statement was the plethora of new data since previous hereditary haemorrhagic telangiectasia (HHT) guidelines generated in 2006 and a systematic Cochrane Review for PAVM embolisation in 2011. The British Thoracic Society (BTS) identified key areas in which there is now evidence to drive a change in practice. Due to the paucity of data in children, this Statement focused on adults over 16 years. The Statement spans the management of PAVMs already known to be present (interventional and medical), screening and diagnosis (for PAVMs and HHT) and follow-up of patients following a first diagnosis, intervention or negative screen for PAVMs. The Good Practice Points (in bold) were generated for a target audience of general respiratory, medical and specialist clinicians and were approved by the BTS Standards of Care Committee, before formal peer review and public consultation. The Statement spans embolisation treatment, accessory medical management and issues related to the likelihood of underlying HHT.
© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Rodrigo Cartin-Ceba, Karen L Swanson, Michael J Krowka
Pulmonary arteriovenous malformations.
Chest. 2013 Sep;144(3):1033-1044. doi: 10.1378/chest.12-0924.
Abstract/Text
Pulmonary arteriovenous malformations (PAVMs) are abnormal vascular structures that most often connect a pulmonary artery to a pulmonary vein, bypassing the normal pulmonary capillary bed and resulting in an intrapulmonary right-to-left shunt. As a consequence, patients with PAVM can have hypoxemia and paradoxical embolization complications, including stroke and brain abscess. PAVMs may be single or multiple, unilateral or bilateral, and simple or complex. Most PAVMs are hereditary and occur in hereditary hemorrhagic telangiectasia, an autosomal dominant vascular disorder, and screening for PAVM is indicated in this subgroup. PAVMs may also be idiopathic, occur as a result of trauma and infection, or be secondary to hepatopulmonary syndrome and bidirectional cavopulmonary shunting. Diagnostic testing involves identifying an intrapulmonary shunt, with the most sensitive test being transthoracic contrast echocardiography. Chest CT scan is useful in characterizing PAVM in patients with positive intrapulmonary shunting. Transcatheter embolotherapy is the treatment of choice for PAVM. Lifelong follow-up is important because recanalization and collateralization may occur after embolization therapy. Surgical resection is rarely necessary and reserved for patients who are not candidates for embolization. Antibiotic prophylaxis for procedures with a risk of bacteremia (eg, dental procedures) is recommended in all patients with PAVM because of the risk of cerebral abscess.
Marie E Faughnan, Johannes J Mager, Steven W Hetts, Valerie A Palda, Kelly Lang-Robertson, Elisabetta Buscarini, Erik Deslandres, Raj S Kasthuri, Andrea Lausman, David Poetker, Felix Ratjen, Mark S Chesnutt, Marianne Clancy, Kevin J Whitehead, Hanny Al-Samkari, Murali Chakinala, Miles Conrad, Daniel Cortes, Claudia Crocione, Jama Darling, Els de Gussem, Carol Derksen, Sophie Dupuis-Girod, Patrick Foy, Urban Geisthoff, James R Gossage, Adrienne Hammill, Ketil Heimdal, Katharine Henderson, Vivek N Iyer, Anette D Kjeldsen, Masaki Komiyama, Kevin Korenblatt, Jamie McDonald, Jack McMahon, Justin McWilliams, Mary E Meek, Meir Mei-Zahav, Scott Olitsky, Sara Palmer, Rose Pantalone, Jay F Piccirillo, Beth Plahn, Mary E M Porteous, Marco C Post, Ivan Radovanovic, Paul J Rochon, Josanna Rodriguez-Lopez, Carlo Sabba, Marcelo Serra, Claire Shovlin, Dennis Sprecher, Andrew J White, Ingrid Winship, Roberto Zarrabeitia
Second International Guidelines for the Diagnosis and Management of Hereditary Hemorrhagic Telangiectasia.
Ann Intern Med. 2020 Dec 15;173(12):989-1001. doi: 10.7326/M20-1443. Epub 2020 Sep 8.
Abstract/Text
DESCRIPTION: Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disease with an estimated prevalence of 1 in 5000 that is characterized by the presence of vascular malformations (VMs). These result in chronic bleeding, acute hemorrhage, and complications from shunting through VMs. The goal of the Second International HHT Guidelines process was to develop evidence-based consensus guidelines for the management and prevention of HHT-related symptoms and complications.
METHODS: The guidelines were developed using the AGREE II (Appraisal of Guidelines for Research and Evaluation II) framework and GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology. The guidelines expert panel included expert physicians (clinical and genetic) in HHT from 15 countries, guidelines methodologists, health care workers, health care administrators, patient advocacy representatives, and persons with HHT. During the preconference process, the expert panel generated clinically relevant questions in 6 priority topic areas. A systematic literature search was done in June 2019, and articles meeting a priori criteria were included to generate evidence tables, which were used as the basis for recommendation development. The expert panel subsequently convened during a guidelines conference to conduct a structured consensus process, during which recommendations reaching at least 80% consensus were discussed and approved.
RECOMMENDATIONS: The expert panel generated and approved 6 new recommendations for each of the following 6 priority topic areas: epistaxis, gastrointestinal bleeding, anemia and iron deficiency, liver VMs, pediatric care, and pregnancy and delivery (36 total). The recommendations highlight new evidence in existing topics from the first International HHT Guidelines and provide guidance in 3 new areas: anemia, pediatrics, and pregnancy and delivery. These recommendations should facilitate implementation of key components of HHT care into clinical practice.
