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European Journal of Radiology 85 (2016) 239–247

Contents lists available at ScienceDirect

European Journal of Radiology

j ourna l h om epage: www.elsev ier .com/ locate /e j rad

emorrhagic infiltration of the aortopulmonary adventitia: Aomplication of acute aortic dissection

. Guilmettea, A. Semionovb, C. Denniec, G. Gahided, J. Pressaccoe, R. Fraser f,.-P. Cordeaug, C. Chartrand-Lefebvreg,∗

Department of Pathology, Centre Hospitalier de l’Université de Montréal, Hôpital Saint-Luc, 1058 rue Saint-Denis, Montréal, Québec H2X 3J4, CanadaDepartment of Radiology, Royal Victoria Hospital, 687 Pine Avenue West, Montreal, Québec H3A 2B4, CanadaDepartment of Diagnostic Imaging, The Ottawa Hospital General Campus, Room S2, Box 232, 501 Smyth Road, Ottawa, Ontario K1H 8L6, CanadaDepartment of Radiology, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, 3001, 12e Avenue Nord, Sherbrooke, Québec J1H 5N4,anadaDepartment of Radiology, Hôpital du Sacré-Cœur de Montréal, 5400 ouest, boul. Gouin, Montréal, Québec H4J 1C5, CanadaDepartment of Pathology, Montreal General Hospital, 1650 Cedar Ave, Montreal, Quebec H3G 1A4, CanadaDepartment of Radiology, Centre Hospitalier de l’Université de Montréal, Hôtel-Dieu du CHUM, 3840 rue Saint-Urbain, Montréal, Québec H2W 1T8,anada

r t i c l e i n f o

rticle history:eceived 29 September 2015eceived in revised form5 November 2015ccepted 20 November 2015

eywords:ortic dissectionediastinal hemorrhage

ortic ruptureortopulmonary adventitiaomputed tomography

a b s t r a c t

Background: Hemorrhagic infiltration of the common aortopulmonary adventitia is an infrequent compli-cation of acute aortic dissection, most frequently Stanford type A. The radiological interpretation of thisfinding may be a diagnostic challenge. The objective of this multicenter case series is to review the radio-logical and pathological findings of hemorrhagic infiltration of the aortopulmonary adventitia secondaryto acute aortic dissection, and to describe the pathophysiology underlying this complication.Material and methods: The study includes 20 cases of aortic dissection with hemorrhagic infiltrationof the aortopulmonary adventitia. These are 17 cases with computed tomography (CT) data obtainedfrom 5 academic centers. Three other cases were retrieved through a search of autopsy reports. Clinical,radiological and pathological data were collected.Results: Linear foci of moderately increased attenuation were seen along the wall of the proximal pul-monary arteries in 4 cases on unenhanced CT. Contrast-enhanced CT showed soft-tissue thickening along

orta these walls in all imaging cases, with some degree of narrowing of the lumen of the pulmonary arteries.Peribronchovascular ground-glass opacities or consolidation were present in 4 cases.Conclusion: Hemorrhagic infiltration of the common aortopulmonary adventitia is an infrequent com-plication of acute type A aortic dissection. The radiologist should be aware of its pathophysiology andimaging findings in order to make a prompt diagnosis in an urgent setting.

© 2015 Elsevier Ireland Ltd. All rights reserved.

. Introduction

A rupture of the thoracic aorta, secondary to acute dissec-ion, is a critical complication, resulting in a 20% mortality rate inhe first 24 h, and a 30% mortality rate within 48 h [1]. Rupturento the mediastinum is often diffuse, resulting in hemomedi-stinum. Extravasated blood can then extend into the pleural or

ericardial spaces, and result in hemothorax or hemopericardium,ith tamponade [2,3], respectively. Blood extravasation into the

∗ Corresponding author. Fax: +1 514 412 7193.E-mail address: chartrandlef@videotron.ca (C. Chartrand-Lefebvre).

ttp://dx.doi.org/10.1016/j.ejrad.2015.11.025720-048X/© 2015 Elsevier Ireland Ltd. All rights reserved.

extrapleural space along the left subclavian artery can create theso-called ‘apical cap’ [4,5] on the chest radiograph.

Infrequently, rupture of an acute aortic dissection may result inhemorrhagic infiltration along the common connective sheath oradventitia shared by the aorta and the central pulmonary arteries[6]. Perivascular extravasation of blood may then spread along thepulmonary arteries to the peribronchovascular pulmonary intersti-tium [2,7–9]. Prompt recognition of this unusual complication onCT requires an understanding of the basic anatomic pathways andpathophysiologic mechanisms that lead to this phenomenon.

The objective of this multicenter case series is to review theradiological and pathological findings of hemorrhagic infiltration ofthe aortopulmonary adventitia secondary to acute aortic dissection,and to describe the pathophysiology underlying this complication.

240 J. Guilmette et al. / European Journal of Radiology 85 (2016) 239–247

Fig. 1. A–C 49-year-old man with chest pain (Patient 2). A conventional coronary angiogram was performed and followed by a non-enhanced (A, B) and contrast-enhanced(C) chest CT. (A, B) Linear increased attenuation is seen along the wall of the proximal pulmonary arteries (white arrows). (C) There is an intimal flap (black arrow) in theascending aorta, and mural thickening of the pulmonary arteries (white arrows). (D) 89-year-old woman with acute type A aortic dissection (Patient 6). Non-enhanced chestCT shows increased attenuation along the wall of the right pulmonary artery (white arrow).

Fig. 2. 70-year-old woman presented with angina (Patient 5). A conventional coronary angiogram was performed, during which an iatrogenic right coronary dissectionoccurred with retrograde aortic extension. Successful right coronary artery stenting sealed the origin of the dissection, and restored the patency of the coronary artery lumen.(A) A non-enhanced ECG-gated 64-slice CT obtained immediately after cardiac catheterization shows the persistent, highly dense extravascular contrast material (whitearrows) in the wall of the right sinus of Valsalva. A stent in the proximal right coronary artery is seen (yellow arrow). (B) Dense extravascular contrast material (white arrows)is also seen along the main pulmonary artery and the ascending aorta, presumably contained in the aortopulmonary adventitia (white arrows). The retroaortic (one yellowarrow) and anterior (two yellow arrows) portions of the superior recess of the transverse sinus of the pericardium are also seen. The superior pericardial recess is normal,without contrast material, and clearly distinct from the infiltrated and dense aortopulmonary adventitia. (For interpretation of the references to colour in this figure legend,the reader is referred to the web version of this article.)

J. Guilmette et al. / European Journal of Radiology 85 (2016) 239–247 241

Fig. 3. Contrast-enhanced 16-slice CT in a 72-year-old man with chest pain (Patient 1), on admission (A, B), and six days following aortic surgery (C). (A, B) There is anacute dissection of the ascending aorta (A, yellow arrow) with rupture and contrast extravasation above the left sinus of Valsalva (B, yellow arrow), and extension into thea the m( , soft-w ur in t

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ortopulmonary adventitia (A–B, white arrows). Severe compression of the lumen ofA, arrowhead). (C) Six days post-replacement of the ascending aorta and hemi-archith decreased narrowing of its lumen. (For interpretation of the references to colo

. Materials and methods

The study was approved by the respective institutional reviewoards with an informed consent waiver.

.1. Study patients

.1.1. Imaging casesThe medical and imaging records of patients who presented

ith CT findings of acute aortic dissection and hemorrhagic infiltra-ion of the aortopulmonary adventitia between 2008 and 2015 atve academic centers were included and retrospectively reviewed.

.1.2. Pathological casesA search of autopsy reports from 2006 to 2013 and 2012 to

013 at two of the five academic centers led to the identificationf three autopsy reports describing acute aortic dissection withemorrhagic infiltration of the aortopulmonary adventitia.

.2. Technique

.2.1. CT techniqueAs this study was retrospective, a variety of multislice CT scan-

ers were used and CT imaging protocols were not standardized.mage quality in each case allowed an excellent assessment ofascular, mediastinal and pulmonary findings under review. Thehoracic CT scans included unenhanced and contrast-enhancedxaminations, some of which were done using a CT aorticngiogram protocol. There was one CT pulmonary angiogram. Slicehickness varied between 0.6 to 1.5 mm. Most examinations wereot ECG-gated.

.2.2. Pathological techniqueAutopsies were performed by board certified anatomical pathol-

gists. A Y-shaped incision of the anterior aspect of the torso waserformed. After exenteration, a careful description of each inter-al organ was recorded, including dimensions and weight, as perospital autopsy regulations and protocols.

ain and right pulmonary arteries is seen. There is also right lower lobe consolidationtissue attenuation of the pulmonary artery wall is still seen (white arrow), howeverhis figure legend, the reader is referred to the web version of this article.)

2.3. CT image analysis

CT signs considered as hemorrhagic infiltration along thepulmonary arteries were circumferential areas with attenuationhigher than blood that completely or partially surrounded thelumen of the pulmonary arteries on unenhanced CT. On contrast-enhanced CT, circumferential areas with soft-tissue attenuationthat completely or partially surrounded the pulmonary arterieswere interpreted as hemorrhagic infiltration. Stenosis of the lumen(% reduction in diameter) of pulmonary arteries were assessedon contrast-enhanced scans. Ground-glass opacities or consolida-tions with peribronchovascular distribution were interpreted asprobable lung hemorrhage extended from the pulmonary arteyadventitia, in the absence of a clinical context or CT signs of otheracute or chronic lung pathologies that could give similar ground-glass opacities or consolidations. CT images were also evaluatedfor classic aortic dissection versus mural hematoma, mediastinalhemorrhage (extravasation of contrast media in the mediastinumor mediastinal fat stranding) and hemopericardium (pericardialeffusion with high attenuation).

3. Results

3.1. Imaging cases

Seventeen patients (10 males, 7 females; mean age 70 years(range 49–90 years)) with CT findings of acute aortic dissectionwith hemorrhagic infiltration of the aortopulmonary adventitia(Table 1) were included. Twelve patients suffered from chest pain,and 10 had a history of poorly controlled systemic hypertension. In1 patient, the aortic dissection was felt to be secondary to an iatro-genic dissection of the right coronary artery, which occurred duringconventional coronary angiography [10]. Three patients died as aresult of their aortic dissection (patients no. 6, 15 and 17).

3.1.1. Vascular findings on unenhanced CTAn unenhanced CT was available for 7 patients (Table 1). Linear

foci of moderately increased attenuation were seen along the wall

242

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Table 1Imaging cases of acute aortic dissection with hemorrhagic infiltration of the common aortopulmonary adventitia.

Patient Age (years) Gender Risk factors Initial symptoms IV contrast Site of aortic dissection orhematoma

Pulmonary artery Other imaging findings

Involved Luminal narrowing (%)

1. 72 M HTN Chest pain C+ A RPA, LPA 90% Mediastinal hemorrhage,pulmonary consolidation,ground glass

2. 49 M HTN Chest pain C−/C+ A RPA, LPA 20% Hemopericardium3. 90 F HTN Epigastric pain C−/C+ A MPA 10% Hemopericardium4. 62 M HTN Chest pain C−/C+ A, T RPA, LPA 60% Mediastinal hemorrhage,

hemopericardium,pulmonary ground glass

5. 70 F HTN, DLPD, Aortocoronaryiatrogenic dissection

Chest pain C−/C+ A PT 25%

6. 89 F DM2, HTN, AAA Loss of consciousness C−/C+ A RPA, LPA 50% Mediastinal hemorrhage,hemopericardium,pulmonary ground glass

7. 68 F Severescoliosis, dwarfism Hemoptysis,chest pain C+ A, T, D RPA 40% Mediastinal hemorrhage,pulmonary ground glass

8. 66 M HTN, DLPD Low back pain C+ A RPA 25%9. 71 M HTN Chest pain C+ A, T, D LPA 70% Aortic intramural

hematoma10. 74 M Aortic atheromatous ulcer Chest pain C+ A LPA 10% Mediastinal hemorrhage,11. 68 M HTN Chest pain C+ A, T, D RPA, LPA 50% Hemopericardium12. 74 F None Low back pain C+ A RPA, LPA 30% Hemopericardium13. 61 F HTN Chest pain C−C+ A, T, D RPA, LPA, MPA 20% Aortic intramural

hematoma14. 70 M None Chest pain C+ A, T RPA, LPA 30% Mediastinal hemorrhage,

Hemopericardium15. 67 F AbAA Chest pain C+ A RPA, MPA 10%16. 74 M Trauma, chest pain C+ A, T, D RPA, LPA, MPA 10% Mediastinal hemorrhage,

hemopericardium17. 56 M AAA Chest pain C−C+ A, T, D RPA, LPA, MPA 20% Aortic intramural

hematoma, Mediastinalhemorrhage

A: ascending. AAA: ascending aortic aneurysm. AbAA: Abdominal aorta aneurysm. AN: anterior. C+: with contrast. C−: without contrast. D: descending. DLPD: dyslipidemia. DM2: type 2 diabetes. F: female. HTN: hypertension.LL: left lateral. LPA: left pulmonary artery. M: male. P: posterior. MPA: main pulmonary artery. N/A: not available. PT: pulmonary artery trunk. RAA: rupture of ascending aorta. RCA: right coronary artery. RL: right lateral. RPA:right pulmonary artery. T: transverse.

J. Guilmette et al. / European Journal o

Fig. 4. 66-year-old man with chest pain. Contrast-enhanced chest CT. Acute dissec-tion of the ascending aorta (yellow arrow), associated with thickening of posteriorand medial walls of the right and left pulmonary arteries, respectively, likely due toh(r

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emorrhagic infiltration of the common aortopulmonary adventitia (white arrows).For interpretation of the references to colour in this figure legend, the reader iseferred to the web version of this article.)

f the proximal pulmonary arteries in 4 cases (Fig. 1). These extralu-inal foci of increased attenuation were likely due to extravasated

lood, except in the case of the patient with iatrogenic aortocoro-ary dissection (Patient 5). In this case, since the unenhanced CTas performed immediately after conventional coronary angiogra-hy, the extraluminal foci of increased attenuation along the wall ofhe ascending aorta and proximal pulmonary arteries were causedy the presence of the extravasated contrast agent from the recentoronary angiogram, contained in the aortopulmonary adventitiaFig. 2).

.1.2. Vascular findings on contrast-enhanced CTSoft-tissue thickening was seen along the wall of the pulmonary

rteries all imaging cases (n = 17) (Fig. 1). The soft-tissue thickeningas seen in continuity with similar complete or partial circum-

erential thickening of the ascending aortic wall in 12 cases. Allontrast-enhanced examinations showed some degree of narrow-ng of the lumen of the pulmonary arteries, with lumen stenosisanging from 10 to 90% in diameter (Table 1). For the patient with

0% pulmonary artery lumen narrowing (Patient 1, Table 1), follow-p CT examinations at 6 and 21 days showed partial regression ofhe pulmonary artery compression (Fig. 3). In this patient, the sitef aortic rupture was located at the inferior posterolateral wall of

able 2athological cases of acute aortic dissection and hemorrhagic infiltration of the common

Patients Age(years)

Gender Risks factors Initialsymptoms

1. 91 F AAAHTNSmoker

Chest pain

2. 45 F Smoker DLPD Epigastric painChest pain

3. 33 M None N/A

: female. M: male. AAA: ascending aortic aneurysm. HTN: hypertension. DLPD: dyslipideeft pulmonary artery. N/A: not available.

f Radiology 85 (2016) 239–247 243

the ascending aorta, near the origin of the right pulmonary artery(Fig. 3).

The perivascular thickening involved the right pulmonary arteryin 13 cases, the left pulmonary artery in 12 cases, and both rightand left pulmonary arteries in 10 cases (Fig. 4). In general, the rightpulmonary artery was the most extensively involved and narrowed.The main pulmonary artery showed perivascular thickening in 5cases (Table 1).

3.1.3. Other mediastinal findingsThree patients presented an intramural hematoma. All other

patients had classic aortic dissection. Seven patients showed slightstranding of the mediastinal fat, in addition to the soft-tissue infil-tration of the aortopulmonary adventice. Only one patient showedactive contrast agent extravasation in the mediastinum (Patient 1).Eight patients showed pericardial effusion with high attenuationsuggestive of hemopericardium.

3.1.4. Pulmonary parenchymal findingsIn 4 cases, ground-glass opacities or consolidation were present

with peribronchovascular distribution up to the subsegmental pul-monary arteries (Fig. 5). Ground-glass attenuation or consolidationwas observed in patients with ≥40% luminal narrowing of the prox-imal pulmonary arteries (Table 1).

3.2. Autopsy cases

3.2.1. Autopsy findingsWe identified 3 patients (1 male, 2 females; mean age 56 years)

with autopsy findings of acute aortic dissection associated withhemorrhagic infiltration of the aortopulmonary adventitia, thatwere identified through our institutions’ autopsy database. None ofthese patients could be imaged prior to their sudden death (Table 2).

Case 1. A 91 year-old woman presented with severe chest painand died suddenly upon her arrival in the emergency department.The autopsy showed an aneurysm of the ascending aorta measur-ing 7 cm in diameter, with a transverse parietal tear of 9 cm inlength (Fig. 6). Complete transection of the intima and media wasseen, as well as a partial tear of the adventitia. There was hem-orrhagic infiltration along the adventitia of the main pulmonaryartery, and right and left main pulmonary arteries, with extensioninto the lung parenchyma through both hila, spreading along lobarand segmental bronchi, as well as pulmonary arteries and veins(Fig. 6).

Case 2. A 45 year-old woman presented with severe chest andepigastric pain and suffered a cardiac arrest soon after arrival in the

emergency department. The autopsy showed an aneurysm of theascending aorta measuring 4.1 cm in diameter with a transparietalfissure measuring 1 cm in length, located in the right lateral wall ofthe ascending aorta, likely due to the rupture of an acute dissection.

aortopulmonary adventitia.

Site of aorticdissection

Pulmonary arteryinvolved

Other findings

A RPA, LPA, MPA Hemopericardium,hemothorax,pulmonaryhemorrhage

A RPA, MPA

A RPA, LPA, MPA Pulmonaryhemorrhage

mia. A: ascending. MPA: main pulmonary artery. RPA: right pulmonary artery. LPA:

244 J. Guilmette et al. / European Journal of Radiology 85 (2016) 239–247

Fig. 5. (A–B) 89-year-old woman found unconscious at home (Patient 6) (same patient as in Fig. 1D). (A) Acute aortic dissection, Stanford type A (yellow arrow), withhemorrhagic pericardial effusion (arrowhead). (B) Peribronchovascular ground glass attenuation in the right lower lobe (white arrow); (C–D) 68-year-old woman with chestpain (patient 7). (C) Acute aortic dissection, Stanford type A (yellow arrows). (D) Ground glass attenuation and thickening of the wall of the pulmonary arteries in the rightlower lobe (arrows) (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)

F ure (ba pulm

Eatm

Ct

ig. 6. 90-year-old woman with severe chest pain. (A) Site of the linear aortic ruptrrow). (C) Coronal section of the left lung shows hemorrhagic infiltration along the

xtensive hemorrhagic infiltration of the central pulmonary arterydventitia was noted, extending into the right hilum and infiltrating

he entire circumference of the right mainstem bronchus and right

ain and middle lobe pulmonary arteries (Fig. 7).

ase 3. A 33 year-old man, without known past medical his-ory, died suddenly prior to hospitalization. Post mortem findings

lack arrow). (B) Left lung. Hemorrhagic infiltration of the pulmonary hilum (blackonary arteries, veins, and bronchi (black arrows).

revealed an aneurysm of the ascending aorta measuring 4.5 cmin diameter and 6 cm in length. The dissection measured 6.8 cm

long and originated in the aortic root immediately above the aorticvalve, a few millimeters away from the left coronary artery ostium.Careful examination of the mediastinum and great vessels revealedhemorrhagic infiltration surrounding the main pulmonary artery,

J. Guilmette et al. / European Journal of Radiology 85 (2016) 239–247 245

Fig. 7. 45-year-old woman with severe epigastric pain. Right lung. Hemorrhagic infiltration surrounding the right main bronchus (yellow arrow), pulmonary artery (whitearrow) and pulmonary vein (black arrow) of the middle lobe. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version ofthis article.)

F ction

h ) Cro( eries w

ed

3

p

ig. 8. 91-year-old woman with severe thoracic pain. Routine stain. (A) Cross seemorrhagic infiltration of the common aortopulmonary adventitia (black arrow). (Bbottom) confirmed hemorrhagic infiltration (black arrow) along the segmental art

xtending along the wall of the right and left pulmonary arteriesown to the segmental arteries within the lung parenchyma.

.2.2. Histological findingsCross-section of the ascending aorta at the level of the main

ulmonary artery in our autopsy cases showed dissection involv-

of the ascending aorta (left) in relation to the pulmonary artery (right) showingss section of the lung parenchyma (top) in relation to a segmental pulmonary artery

ithin the lung parenchyma.

ing the intima, media and adventitia, associated with hemorrhagicinfiltration into the common adventitia shared by both great ves-

sels. Histological examination of the lung parenchyma confirmedhemorrhagic infiltration along the segmental pulmonary arteries(Fig. 8).

246 J. Guilmette et al. / European Journal of Radiology 85 (2016) 239–247

Fig. 9. (A) Normal heart pre-fixation. Intact common aortopulmonary adventitia (arrow)Common aortopulmonary adventitia (between clamps) separated from the ascending aor

Fig. 10. Schematic illustration of the thoracic aorta in relation to the proximal pul-monary arteries. The lighter colored area illustrates the common aortopulmonaryadventitia and its potential pathway running centrally from the ascending aortaap

4

wrmCsmaTs

literature [17,18]. Boyd [19] before the advent of CT in 1924, in a

nd main pulmonary artery distally in the mediastinum around the right and leftulmonary arteries, then into the hilum and perihilar region.

. Discussion

This is a retrospective multicenter case series of 20 patientsith acute type A aortic dissection with limited mediastinal

upture and hemorrhagic infiltration of the common aortopul-onary adventitia, including imaging and pathological findings.

ontrast-enhanced CT in all of our imaging cases showedoft-tissue attenuation thickening along the wall of central pul-

onary arteries. When non-enhanced CT was available, pulmonary

rteries walls showed moderately increased attenuation in 4 cases.his finding on unenhanced CT scan is relatively singular, andhould alert the radiologist to look for an acute aortic dissection,

between the pulmonary trunk (left) and the aorta (right). (B) Heart post-fixation.ta, forming a potential space in a normal patient.

if this hypothesis had not been raised earlier. Peribronchovascularground-glass opacities or consolidation were present in 4 imagingcases. Our results confirm previously reported imaging characteris-tics of this complication in the context of an acute aortic dissection[6–9,11]. This multicenter series is the second largest after theseries of Sueyoshi et al. [6] who reported 21 cases of patients withruptured acute type A aortic dissection and hemorrhagic infiltrationof the aortopulmonary adventitia [6].

During early embryogenesis, fusion of the two endocardialtubes usually gives rise to the primitive heart tube composed offive regions: truncus arteriosus, bulbus cordis, primitive ventricle,primitive atrium, and sinus venosus [12]. Then, the truncus arte-riosus and the cranial end of the bulbus cordis become graduallyseparated by the aorticopulmonary septum. This septum is com-posed of two ridge-like projections derived from cardiac neuralcrest cells, which later fuse together to create a continuous bridgeand form the separate lumens of the aorta and main pulmonaryartery [13,14]. As can be seen in Fig. 9, illustrating a normal anatom-ical specimen of the human heart and great arteries, a commonsheath of loose connective tissue or adventitia is shared by theaorta and central pulmonary arteries, and is a likely remnant ofthe primitive aorticopulmonary septum. As shown in our imag-ing and pathological findings, as well as in findings reported in thepathological literature [15], this common aortopulmonary adven-titia seems to run centrally along the ascending aorta and the mainpulmonary artery (Fig. 10), then distally to surround the mediasti-nal portions of the right and left pulmonary arteries. Knowledgeof the existence of this perivascular anatomical virtual space at theroot of the great vessels is central to the understanding of the mech-anism by which the extravasation of blood in cases of rupturedtype A aortic dissection may remain confined along the pulmonaryarteries. CT findings of peribronchovascular infiltration suggest thateither this common adventitia extends further into the perihilarregion of the lung (Fig. 10), as postulated by Panicek et al. [2], or,alternatively, that the high pressure within the blood-infiltratedpulmonary adventitia causes its rupture and subsequent hemor-rhage into the perihilar lung, as proposed by Milne and Cyrlak [16].Of note, two of our pathological cases confirmed hemorrhagic infil-tration in the lung at histology, extending from along the proximalpulmonary arteries.

This complication of acute dissection has also been describedas an acquired aortopulmonary fistula, especially in the surgical

survey of 4000 autopsy cases of thoracic aorta aneurysms, reportedrupture “into” a pulmonary artery in 45 cases (1.1%). However, in1958, Hirst et al. [18] reported no case of aortopulmonary fistula

rnal o

ipo2u

firtidl

maia

C

R

[

[

[

[

[

[

[

[lung, Ann. Thorac. Surg. 100 (2015) 315–318.

[18] A.E. Hirst, V.J. Johns, S.W. Kime, Dissecting aneurysm of the aorta; a review of

J. Guilmette et al. / European Jou

n 505 cases of aortic dissection. Sueyoshi et al. [6] reviewed 232atients with Stanford A aortic dissection at CT, and found hem-rrhagic infiltration of the common aortopulmonary adventitia in1 cases (9%). We hypothesize that this complication is probablynder-recognized.

Our series included patients with either imaging or pathologicalndings. However since no case included both types of data, directadiopathological correlation was not available in this study. Dueo our limited number of cases, we were not able to correlate imag-ng findings to poor prognosis. Sueyoshi et al. [6] found classicalissection (in comparison to intramural hematoma) and alveolar

ung infiltration to be related to a fatal pronostic.In conclusion, hemorrhagic infiltration of the common aortopul-

onary adventitia is an infrequent complication of acute type Aortic dissection. The radiologist should be aware of its pathophys-ology and imaging findings in order to make a prompt diagnosis inn urgent setting.

onflict of interest

None.

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