Original Article
Venous sac embolization of pulmonary arteriovenous malformation: safety and effectiveness at mid-term follow-up
Acta Radiologica 2014, Vol. 55(9) 1093–1098 ! The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0284185113512123 acr.sagepub.com
Kenji Kajiwara1, Masaki Urashima2, Takuji Yamagami1, Hideaki Kakizawa1, Noriaki Matsuura2, Akiko Matsuura2, Tae Ohnari2, Masaki Ishikawa1 and Kazuo Awai1
Abstract Background: The standard technique for the transcatheter treatment of pulmonary arteriovenous malformations (PAVMs) involves deploying coils into the feeding arteries. We investigated whether venous sac embolization would also be a safe and useful treatment method. Purpose: To evaluate the safety and outcomes of venous sac embolization for PAVMs. Material and Methods: This study included 15 consecutive patients (1 man, 14 women; mean age, 54 years; range, 22– 76 years) with 50 PAVMs who underwent 26 procedures; four had a history of earlier cerebral infarction or exertional dyspnea. We first placed 0.018-inch interlocking detachable and/or 0.018-inch or 0.010-inch Guglielmi detachable coils to prevent systemic migration from the venous sac. We then packed the sac as tightly as possible and embolized the orifice at the proximal feeding artery. We used angiographic, clinical, and computed tomography (CT) studies to evaluate the treatment outcomes and safety of these procedures. The mean follow-up was 16 months (range, 3–63 months) in 12 patients with 43 PAVMs; three patients (7 PAVMs) were lost to follow-up. Results: Immediate post-embolization angiography confirmed complete primary occlusion in 47 of 50 lesions (94%). Minor complications arose in two of 26 procedures (7.7%); they were abnormal electrocardiograms without symptoms during and pleurisy immediately after the procedure. During follow-up, 40 PAVMs were free of CT evidence of reperfusion. The mean partial arterial oxygen pressure increased from 75.3% 13.6 before embolization to 85.4% 16.3 after embolization (P < 0.01, t-test). Of the 12 patients who were available for follow-up, none experienced new-onset paradoxical embolization; pre-treatment exertional dyspnea was alleviated in one patient. There were no major complications. Conclusion: Venous sac embolization for PAVMs might be safe and more effective with no reperfusion than the standard pulmonary arterial embolization.
Keywords Vascular, interventional, embolization, lung, adults, AVM Date received: 8 May 2012; accepted: 17 October 2013
Introduction Pulmonary arteriovenous malformations (PAVMs) are abnormal direct connections from the pulmonary arteries to the venous circulation with no intervening capillary beds. They result in a right-to-left shunt that often leads to hypoxemia or cardiac insufficiency. Symptomatic as well as asymptomatic patients are at risk for paradoxical embolization and subsequent
1 Department of Diagnostic Radiology, Hiroshima University Hospital, Hiroshima, Japan 2 Department of Radiology, Hiroshima City Hospital, Hiroshima, Japan
Corresponding author: Kenji Kajiwara, Department of Diagnostic Radiology, Hiroshima University Hospital, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan. Email: [email protected]
Downloaded from acr.sagepub.com at CHINESE UNIV HONG KONG LIB on February 5, 2015
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Acta Radiologica 55(9)
stroke, transient ischemic attack, or brain abscess due to the lack of the pulmonary filtering capillary bed (1–7). PAVMs can be classified into simple and complex types (6). Simple type PAVMs manifest a single segmental artery and drainage vein while the complex type exhibits two or more supply arteries and one or two drainage veins. Embolotherapy, a minimally invasive technique, has replaced surgery for the treatment of patients with PAVMs (3–5,7,8). The standard method of transcatheter embolization of PAVMs involves deploying coils into the feeding arteries (3). More distal embolization of the feeders close to the venous sac avoids infarction of adjacent normal lung tissue. However, as reperfusion was observed in 2.8–13% of cases post embolization of the feeding arteries, this issue must be addressed (2–4,9). Although venous sac embolization of PAVMs has been reported to risk intraprocedural rupture and coil protrusion into normal pulmonary veins (5,10,11), we found that it was safe and reduced the incidence of post-treatment reperfusion. We now present a retrospective evaluation of its safety and outcomes in a mid-term follow-up study of venous sac embolization to treat patients with PAVMs.
Material and Methods Our institutional review board waived approval for this retrospective study.
Patients Written prior informed consent was obtained from all patients. Between August 2004 and December 2010, 15 consecutive patients (1 man, 14 women; mean age, 54 years; range, 22–76 years) underwent 26 venous sac embolization procedures to address 50 PAVMs. Of these, 24 PAVMs were detected incidentally on chest radiographs or computed tomography (CT) scans of 11 patients with no clinical symptoms. The other 26 PAVMs were found in four patients with clinical symptoms; two patients, one harboring 19 PAVMs and the other one PAVM, had a history of cerebral infarction. The remaining two patients, one with five PAVMs and the other with one PAVM, presented with exertional dyspnea. The diagnosis of PAVM was based on CT and pulmonary angiography findings. According to the classification of White et al. (6), 49 PAVMs were simple, the other was complex. The diameter of the feeding arteries, venous sacs, and drainage veins were in the range of 1–7 mm (mean, 3.7 mm), 1–27 mm (mean, 8.4 mm), and 1–10 mm (mean 4.1 mm), respectively. We did not adhere to the ‘‘3 mm rule’’ stating that PAVMs whose feeders are 3 mm in diameter should
be treated to prevent complications (1). Rather, we treated small PAVMs (feeding artery diameter
Venous sac embolization of pulmonary arteriovenous malformation: safety and effectiveness at mid-term follow-up
Acta Radiologica 2014, Vol. 55(9) 1093–1098 ! The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0284185113512123 acr.sagepub.com
Kenji Kajiwara1, Masaki Urashima2, Takuji Yamagami1, Hideaki Kakizawa1, Noriaki Matsuura2, Akiko Matsuura2, Tae Ohnari2, Masaki Ishikawa1 and Kazuo Awai1
Abstract Background: The standard technique for the transcatheter treatment of pulmonary arteriovenous malformations (PAVMs) involves deploying coils into the feeding arteries. We investigated whether venous sac embolization would also be a safe and useful treatment method. Purpose: To evaluate the safety and outcomes of venous sac embolization for PAVMs. Material and Methods: This study included 15 consecutive patients (1 man, 14 women; mean age, 54 years; range, 22– 76 years) with 50 PAVMs who underwent 26 procedures; four had a history of earlier cerebral infarction or exertional dyspnea. We first placed 0.018-inch interlocking detachable and/or 0.018-inch or 0.010-inch Guglielmi detachable coils to prevent systemic migration from the venous sac. We then packed the sac as tightly as possible and embolized the orifice at the proximal feeding artery. We used angiographic, clinical, and computed tomography (CT) studies to evaluate the treatment outcomes and safety of these procedures. The mean follow-up was 16 months (range, 3–63 months) in 12 patients with 43 PAVMs; three patients (7 PAVMs) were lost to follow-up. Results: Immediate post-embolization angiography confirmed complete primary occlusion in 47 of 50 lesions (94%). Minor complications arose in two of 26 procedures (7.7%); they were abnormal electrocardiograms without symptoms during and pleurisy immediately after the procedure. During follow-up, 40 PAVMs were free of CT evidence of reperfusion. The mean partial arterial oxygen pressure increased from 75.3% 13.6 before embolization to 85.4% 16.3 after embolization (P < 0.01, t-test). Of the 12 patients who were available for follow-up, none experienced new-onset paradoxical embolization; pre-treatment exertional dyspnea was alleviated in one patient. There were no major complications. Conclusion: Venous sac embolization for PAVMs might be safe and more effective with no reperfusion than the standard pulmonary arterial embolization.
Keywords Vascular, interventional, embolization, lung, adults, AVM Date received: 8 May 2012; accepted: 17 October 2013
Introduction Pulmonary arteriovenous malformations (PAVMs) are abnormal direct connections from the pulmonary arteries to the venous circulation with no intervening capillary beds. They result in a right-to-left shunt that often leads to hypoxemia or cardiac insufficiency. Symptomatic as well as asymptomatic patients are at risk for paradoxical embolization and subsequent
1 Department of Diagnostic Radiology, Hiroshima University Hospital, Hiroshima, Japan 2 Department of Radiology, Hiroshima City Hospital, Hiroshima, Japan
Corresponding author: Kenji Kajiwara, Department of Diagnostic Radiology, Hiroshima University Hospital, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan. Email: [email protected]
Downloaded from acr.sagepub.com at CHINESE UNIV HONG KONG LIB on February 5, 2015
1094
Acta Radiologica 55(9)
stroke, transient ischemic attack, or brain abscess due to the lack of the pulmonary filtering capillary bed (1–7). PAVMs can be classified into simple and complex types (6). Simple type PAVMs manifest a single segmental artery and drainage vein while the complex type exhibits two or more supply arteries and one or two drainage veins. Embolotherapy, a minimally invasive technique, has replaced surgery for the treatment of patients with PAVMs (3–5,7,8). The standard method of transcatheter embolization of PAVMs involves deploying coils into the feeding arteries (3). More distal embolization of the feeders close to the venous sac avoids infarction of adjacent normal lung tissue. However, as reperfusion was observed in 2.8–13% of cases post embolization of the feeding arteries, this issue must be addressed (2–4,9). Although venous sac embolization of PAVMs has been reported to risk intraprocedural rupture and coil protrusion into normal pulmonary veins (5,10,11), we found that it was safe and reduced the incidence of post-treatment reperfusion. We now present a retrospective evaluation of its safety and outcomes in a mid-term follow-up study of venous sac embolization to treat patients with PAVMs.
Material and Methods Our institutional review board waived approval for this retrospective study.
Patients Written prior informed consent was obtained from all patients. Between August 2004 and December 2010, 15 consecutive patients (1 man, 14 women; mean age, 54 years; range, 22–76 years) underwent 26 venous sac embolization procedures to address 50 PAVMs. Of these, 24 PAVMs were detected incidentally on chest radiographs or computed tomography (CT) scans of 11 patients with no clinical symptoms. The other 26 PAVMs were found in four patients with clinical symptoms; two patients, one harboring 19 PAVMs and the other one PAVM, had a history of cerebral infarction. The remaining two patients, one with five PAVMs and the other with one PAVM, presented with exertional dyspnea. The diagnosis of PAVM was based on CT and pulmonary angiography findings. According to the classification of White et al. (6), 49 PAVMs were simple, the other was complex. The diameter of the feeding arteries, venous sacs, and drainage veins were in the range of 1–7 mm (mean, 3.7 mm), 1–27 mm (mean, 8.4 mm), and 1–10 mm (mean 4.1 mm), respectively. We did not adhere to the ‘‘3 mm rule’’ stating that PAVMs whose feeders are 3 mm in diameter should
be treated to prevent complications (1). Rather, we treated small PAVMs (feeding artery diameter
