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Fatal pulmonary arterial dissection and sudden death as initial manifestation of primary pulmonary hypertension
Cardiovascular Pathology 13 (2004) 230 – 232
Case Report
Fatal pulmonary arterial dissection and sudden death as initial manifestation of primary pulmonary hypertension A case report Vincenzo Arena a, Fabio De Giorgio b, Antonio Abbate c, Arnaldo Capelli a, Domenico De Mercurio b, Arnaldo Carbone a,* a
Department of Morbid Pathology, Faculty of Medicine ‘‘A. Gemelli,’’ Catholic University of Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy b Department of Forensic Medicine, Faculty of Medicine ‘‘A. Gemelli,’’ Catholic University of Sacred Heart, Rome, Italy c Department of Cardiology, Faculty of Medicine ‘‘A. Gemelli,’’ Catholic University of Sacred Heart, Rome, Italy Received 29 December 2003; received in revised form 16 February 2004; accepted 20 February 2004
Abstract We report a rare case of sudden death due to cardiac tamponade following intrapericardial rupture of a main pulmonary artery dissecting aneurysm. On pathology examination, the pulmonary artery showed an intimal tear in an arterial wall area with reduced thickness. However, no degenerative, inflammatory or necrotic processes were evident within the vessel wall. Hypertrophy of the wall of vasa vasorum in the adventitia of the pulmonary artery was found, as well as bilaterally diffuse myointimal arterial hyperplasia of the lung vasculature. According to these findings, we conclude that pulmonary artery rupture occurred in a patient with chronic unrecognized primary pulmonary hypertension. D 2004 Elsevier Inc. All rights reserved. Keywords: Pulmonary artery; Dissection; Aneurysm
1. Introduction
2. Case report
Dissecting aortic aneurysms are a relatively frequent event often associated with sudden death, especially when the ascending aorta is involved [1]. Main pulmonary artery dissection, on the other hand, is a very rare event [2,3], occasionally associated with sudden death. Hemorrhagic pericardial effusion and cardiac tamponade usually follow the outward rupture of the proximal main pulmonary artery. We describe a case of sudden death due to pulmonary artery dissection in a patient with an unremarkable clinical history, who arrived at the Emergency Department in cardiocirculatory arrest.
2.1. Clinical presentation and gross pathologic findings
* Corresponding author. Tel.: +39-06-30154270/+39-06-30154532; fax: +39-06-3051157/+39-06-3051343. E-mail addresses: [email protected], carbone.arnaldo@fastweb net.it (A. Carbone). 1054-8807/04/$ – see front matter D 2004 Elsevier Inc. All rights reserved. doi:10.1016/j.carpath.2004.02.003
A 69-year-old man was found with loss of consciousness on the street by Emergency Service personnel. Emergency maneuvers were performed on site due to cardiac arrest. The resuscitation attempt was however ineffective and the patient was brought to the hospital dead. Postmortem examination was requested by the Emergency Department physician. External examination of the body revealed intense peripheral cyanosis. Hemopericardium (approximately 250 ml) was found upon opening of the chest. Examination of the heart and great vessels revealed the presence of an area of hemorrhage within the adventitia of the main pulmonary artery. When longitudinal section of the vessel was performed, a laminar dissection was found (Fig. 1A). There was an intimal tear of about 5 mm in length in correspondence to the external area of hemorrhage (Fig. 1B). The intimal surface was diffusely yellowish but no atherosclerotic plaques were found.
V. Arena et al. / Cardiovascular Pathology 13 (2004) 230–232
231
3. Discussion
Fig. 1. (A) Main pulmonary artery (truncus pulmonalis, longitudinal section). Hemorrhage within the wall (arrow heads) is shown. In the lower portion of the picture, blood infarction of the wall is seen (arrow). ( B) Intimal tear of approximately 4 mm is present, in correspondence of the area with blood infarction. Note the satellite hemorrhagic foci (dark spots). (C ) Structural irregularities within the vessel wall in proximity of the site of intimal tear. The inner portion of the artery shows a T-shaped gap (upper portion). The external fibers appear partially penetrated by adipose tissue (lower portion) (hematoxylin and eosin, 10). ( D) Myointimal hyperplasia of the adventitial arteries surrounded by blood infarction (hematoxylin and eosin, 10). ( E) Lung. Medial hypertrophy and intimal fibrosis in this lung artery (right structure) suggest chronic pulmonary hypertension (hematoxylin and eosin, 10).
2.2. Histopathology Structural rarefaction of the components of the arterial wall was observed at the site of intimal rupture with the presence of small islands of adipose tissue (Fig. 1C). Adventitial vasa vasorum showed extensive modifications of the vessel wall, in particular, concentric hypertrophy and overall reduced lumen size (Fig. 1D). No degenerative processes such as atherosclerotic and/or mucoid alterations were found, even when using appropriate stainings (data not shown). Moreover, no evidence of inflammatory infiltrate was found. Lung examination revealed extensively edematous parenchyma. The small intraparenchymal arteries showed hypertrophy of the wall with reduction in the lumen size (Fig. 1E).
Pulmonary artery dissection is a rare event, occasionally reported as a cause of sudden death. [2– 6]. The first case in the literature was described by Helmbrechtr in 1842 [4]. It is slightly more frequent in females (male-to-female ratio 1:1.2). Age of onset is variable ranging from 26 to 85 years. The dissection more often involves the main pulmonary artery (72%) or its major branches (left pulmonary artery: 6%; right pulmonary artery: 4%) or both (main trunk and rightartery: 6%; main trunk and both arteries: 2%) [7]. Anecdotal reports of primary causes of pulmonary artery dissection and rupture, such as degeneration associated with Marfan’s disease or cystic medionecrosis of unknown cause, are present in the literature. Other causes of pulmonary artery dissection include invasive procedures such as right heart catheterization and pulmonary artery angiography [7]. Some cases of pulmonary artery dissection and rupture remain unexplained [8]. In a recent review of the literature, however, it was shown that only 19% of cases of pulmonary artery dissection (10 out of 52 cases) had been reported in patients without pulmonary hypertension [7]. In the great majority of cases, indeed, there is an association between pulmonary (primary or secondary) hypertension and dissection. Intracardiac left-to-right shunt and patent ductus arteriosus represent common cardiac causes of secondary hypertension. Noncardiac causes of pulmonary hypertension may be present in various forms such as idiopathic form, veno-occlusive pulmonary disease, primitive medial hypertrophy and pulmonary vasculitis [9]. We describe a case of sudden death due to abrupt main pulmonary artery dissection. An intimal tear was identified at the initial site of dissection, which is very common in aortic disease but only rarely reported in pulmonary artery dissection [7]. Although the patient did not have a diagnosis of pulmonary hypertension, the findings at pathology are strongly suggestive of a primary pulmonary hypertensive condition and therefore support the link between unrecognized pulmonary hypertension and pulmonary artery dissection. In particular, the presence of highly hypertrophied adventitial vasculature and the absence of degenerative disease in the pulmonary artery wall support this hypothesis (Fig. 1C and D), as also reported in the literature [6]. The additional findings of fibrillar disarray and the presence of adipose tissue in the pulmonary artery may suggest the presence of a locus minoris resistentiae within the wall, which may have been relevant to the occurrence of the dissection. The increased stress due to pulmonary artery hypertension may indeed have caused dissection in a rupture-prone site.
References [1] Lie JT. In: Silver MD, editor. Morte improvvisa secondaria a patologie de1 sistema cardiovascolare. Patologia cardiovascolare. Milan: McGraw-Hill, 1994. pp. 643 – 70.
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V. Arena et al. / Cardiovascular Pathology 13 (2004) 230–232
[2] Foord AG, Lewis RD. Primary dissecting aneurysms of the peripheral and pulmonary arteries. Arch Pathol 1959;68:553 – 65. [3] Walley VM, Virmani R, Silver MD. Pulmonary arterial dissections and ruptures: to be considered in patients with pulmonary arterial hypertension presenting with cardiogenic shock or sudden death. Pathology 1990;22:1 – 4. [4] Shilkin KB, Low LP, Chen BT. Dissecting aneurysm of the pulmonary artery. J Pathol 1969;98(1):25 – 9. [5] Luchtrath H. Dissecting aneurysm of the pulmonary artery. Virchows Arch A Pathol Anat Histol 1981;391(2):241 – 7.
[6] Ackermann DM, Edwards WD. Sudden death as the initial manifestation of primary pulmonary hypertension. Am J Forensic Med Pathol 1987;8(2):97 – 102. [7] Inayama Y, Nakatani Y, Kitamura H. Pulmonary artery dissection in patients without underlying pulmonary hypertension. Histopathology 2001;38:435 – 42. [8] Steingrub J, Detore A, Teres D. Spontaneous rupture of pulmonary artery. Crit Care Med 1987;15:270 – 1. [9] Brown DL, Wetli CV, Davis JH. Sudden unexpected death from primary pulmonary hypertension. J Forensic Sci 1981;26(2):381 – 6.
Case Report
Fatal pulmonary arterial dissection and sudden death as initial manifestation of primary pulmonary hypertension A case report Vincenzo Arena a, Fabio De Giorgio b, Antonio Abbate c, Arnaldo Capelli a, Domenico De Mercurio b, Arnaldo Carbone a,* a
Department of Morbid Pathology, Faculty of Medicine ‘‘A. Gemelli,’’ Catholic University of Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy b Department of Forensic Medicine, Faculty of Medicine ‘‘A. Gemelli,’’ Catholic University of Sacred Heart, Rome, Italy c Department of Cardiology, Faculty of Medicine ‘‘A. Gemelli,’’ Catholic University of Sacred Heart, Rome, Italy Received 29 December 2003; received in revised form 16 February 2004; accepted 20 February 2004
Abstract We report a rare case of sudden death due to cardiac tamponade following intrapericardial rupture of a main pulmonary artery dissecting aneurysm. On pathology examination, the pulmonary artery showed an intimal tear in an arterial wall area with reduced thickness. However, no degenerative, inflammatory or necrotic processes were evident within the vessel wall. Hypertrophy of the wall of vasa vasorum in the adventitia of the pulmonary artery was found, as well as bilaterally diffuse myointimal arterial hyperplasia of the lung vasculature. According to these findings, we conclude that pulmonary artery rupture occurred in a patient with chronic unrecognized primary pulmonary hypertension. D 2004 Elsevier Inc. All rights reserved. Keywords: Pulmonary artery; Dissection; Aneurysm
1. Introduction
2. Case report
Dissecting aortic aneurysms are a relatively frequent event often associated with sudden death, especially when the ascending aorta is involved [1]. Main pulmonary artery dissection, on the other hand, is a very rare event [2,3], occasionally associated with sudden death. Hemorrhagic pericardial effusion and cardiac tamponade usually follow the outward rupture of the proximal main pulmonary artery. We describe a case of sudden death due to pulmonary artery dissection in a patient with an unremarkable clinical history, who arrived at the Emergency Department in cardiocirculatory arrest.
2.1. Clinical presentation and gross pathologic findings
* Corresponding author. Tel.: +39-06-30154270/+39-06-30154532; fax: +39-06-3051157/+39-06-3051343. E-mail addresses: [email protected], carbone.arnaldo@fastweb net.it (A. Carbone). 1054-8807/04/$ – see front matter D 2004 Elsevier Inc. All rights reserved. doi:10.1016/j.carpath.2004.02.003
A 69-year-old man was found with loss of consciousness on the street by Emergency Service personnel. Emergency maneuvers were performed on site due to cardiac arrest. The resuscitation attempt was however ineffective and the patient was brought to the hospital dead. Postmortem examination was requested by the Emergency Department physician. External examination of the body revealed intense peripheral cyanosis. Hemopericardium (approximately 250 ml) was found upon opening of the chest. Examination of the heart and great vessels revealed the presence of an area of hemorrhage within the adventitia of the main pulmonary artery. When longitudinal section of the vessel was performed, a laminar dissection was found (Fig. 1A). There was an intimal tear of about 5 mm in length in correspondence to the external area of hemorrhage (Fig. 1B). The intimal surface was diffusely yellowish but no atherosclerotic plaques were found.
V. Arena et al. / Cardiovascular Pathology 13 (2004) 230–232
231
3. Discussion
Fig. 1. (A) Main pulmonary artery (truncus pulmonalis, longitudinal section). Hemorrhage within the wall (arrow heads) is shown. In the lower portion of the picture, blood infarction of the wall is seen (arrow). ( B) Intimal tear of approximately 4 mm is present, in correspondence of the area with blood infarction. Note the satellite hemorrhagic foci (dark spots). (C ) Structural irregularities within the vessel wall in proximity of the site of intimal tear. The inner portion of the artery shows a T-shaped gap (upper portion). The external fibers appear partially penetrated by adipose tissue (lower portion) (hematoxylin and eosin, 10). ( D) Myointimal hyperplasia of the adventitial arteries surrounded by blood infarction (hematoxylin and eosin, 10). ( E) Lung. Medial hypertrophy and intimal fibrosis in this lung artery (right structure) suggest chronic pulmonary hypertension (hematoxylin and eosin, 10).
2.2. Histopathology Structural rarefaction of the components of the arterial wall was observed at the site of intimal rupture with the presence of small islands of adipose tissue (Fig. 1C). Adventitial vasa vasorum showed extensive modifications of the vessel wall, in particular, concentric hypertrophy and overall reduced lumen size (Fig. 1D). No degenerative processes such as atherosclerotic and/or mucoid alterations were found, even when using appropriate stainings (data not shown). Moreover, no evidence of inflammatory infiltrate was found. Lung examination revealed extensively edematous parenchyma. The small intraparenchymal arteries showed hypertrophy of the wall with reduction in the lumen size (Fig. 1E).
Pulmonary artery dissection is a rare event, occasionally reported as a cause of sudden death. [2– 6]. The first case in the literature was described by Helmbrechtr in 1842 [4]. It is slightly more frequent in females (male-to-female ratio 1:1.2). Age of onset is variable ranging from 26 to 85 years. The dissection more often involves the main pulmonary artery (72%) or its major branches (left pulmonary artery: 6%; right pulmonary artery: 4%) or both (main trunk and rightartery: 6%; main trunk and both arteries: 2%) [7]. Anecdotal reports of primary causes of pulmonary artery dissection and rupture, such as degeneration associated with Marfan’s disease or cystic medionecrosis of unknown cause, are present in the literature. Other causes of pulmonary artery dissection include invasive procedures such as right heart catheterization and pulmonary artery angiography [7]. Some cases of pulmonary artery dissection and rupture remain unexplained [8]. In a recent review of the literature, however, it was shown that only 19% of cases of pulmonary artery dissection (10 out of 52 cases) had been reported in patients without pulmonary hypertension [7]. In the great majority of cases, indeed, there is an association between pulmonary (primary or secondary) hypertension and dissection. Intracardiac left-to-right shunt and patent ductus arteriosus represent common cardiac causes of secondary hypertension. Noncardiac causes of pulmonary hypertension may be present in various forms such as idiopathic form, veno-occlusive pulmonary disease, primitive medial hypertrophy and pulmonary vasculitis [9]. We describe a case of sudden death due to abrupt main pulmonary artery dissection. An intimal tear was identified at the initial site of dissection, which is very common in aortic disease but only rarely reported in pulmonary artery dissection [7]. Although the patient did not have a diagnosis of pulmonary hypertension, the findings at pathology are strongly suggestive of a primary pulmonary hypertensive condition and therefore support the link between unrecognized pulmonary hypertension and pulmonary artery dissection. In particular, the presence of highly hypertrophied adventitial vasculature and the absence of degenerative disease in the pulmonary artery wall support this hypothesis (Fig. 1C and D), as also reported in the literature [6]. The additional findings of fibrillar disarray and the presence of adipose tissue in the pulmonary artery may suggest the presence of a locus minoris resistentiae within the wall, which may have been relevant to the occurrence of the dissection. The increased stress due to pulmonary artery hypertension may indeed have caused dissection in a rupture-prone site.
References [1] Lie JT. In: Silver MD, editor. Morte improvvisa secondaria a patologie de1 sistema cardiovascolare. Patologia cardiovascolare. Milan: McGraw-Hill, 1994. pp. 643 – 70.
232
V. Arena et al. / Cardiovascular Pathology 13 (2004) 230–232
[2] Foord AG, Lewis RD. Primary dissecting aneurysms of the peripheral and pulmonary arteries. Arch Pathol 1959;68:553 – 65. [3] Walley VM, Virmani R, Silver MD. Pulmonary arterial dissections and ruptures: to be considered in patients with pulmonary arterial hypertension presenting with cardiogenic shock or sudden death. Pathology 1990;22:1 – 4. [4] Shilkin KB, Low LP, Chen BT. Dissecting aneurysm of the pulmonary artery. J Pathol 1969;98(1):25 – 9. [5] Luchtrath H. Dissecting aneurysm of the pulmonary artery. Virchows Arch A Pathol Anat Histol 1981;391(2):241 – 7.
[6] Ackermann DM, Edwards WD. Sudden death as the initial manifestation of primary pulmonary hypertension. Am J Forensic Med Pathol 1987;8(2):97 – 102. [7] Inayama Y, Nakatani Y, Kitamura H. Pulmonary artery dissection in patients without underlying pulmonary hypertension. Histopathology 2001;38:435 – 42. [8] Steingrub J, Detore A, Teres D. Spontaneous rupture of pulmonary artery. Crit Care Med 1987;15:270 – 1. [9] Brown DL, Wetli CV, Davis JH. Sudden unexpected death from primary pulmonary hypertension. J Forensic Sci 1981;26(2):381 – 6.