Abstract
Thoracic aortic aneurysms represent a potentially life-threatening disease with increasing prevalence, probably related to the increasing mean age of the global population; the complications of thoracic aortic aneurysms can show multiple modes of presentation in the acute phase based on various factors, including the involvement of the structures with which the aneurysm is in close anatomical relationship. With this case report we want to show how it is possible that a complicated ascending aortic aneurysm can mimic an acute pulmonary embolism/acute cor pulmonale in the acute phase; the earliest possible differential diagnosis between pulmonary embolism and acute aortic disease is of crucial importance due to the opposite implications that the treatment of these two diseases have.
<Learning objective: Aortic acute syndromes may mimic acute cor pulmonale; the principal aim is to raise the readers' awareness of this aspect as the earliest possible differential diagnosis between pulmonary embolism and acute aortic disease is of crucial importance due to the opposite implications that the treatment of these two diseases has.>
Keywords: Thoracic aortic aneurysm, Ascending aortic aneurysm, Ruptured aortic aneurysm, Acute pulmonary embolism, Acute cor pulmonale, Right ventricular dysfunction, Pulmonary hypertension
Abbreviations: TAA, thoracic aortic aneurysm; AAA, ascending aortic aneurysm; PA, pulmonary artery; ABG, arterial blood gas analysis; ECG, electrocardiogram; TTE, transthoracic echocardiography; RV, right ventricle; CT, computed Tomography; RVSP, right ventricle systolic pressure
Introduction
Thoracic aortic aneurysms (TAA), as well as representing potentially life-threatening conditions, are characterized by a certain risk of compression of the anatomical structures in direct relationship with the ascending aorta itself. Specifically, ascending aortic aneurysm (AAA) may involve the main pulmonary artery (PA) or its branches by compression or by the development of an aortopulmonary artery fistula; extrinsic compression of the PA is rare, further rarer, with very few reported cases, is the rupture of the aneurysm with acute compression of a main branch of the PA; here we present a case of acute cor pulmonale with right ventricular acute failure and right ventricular systolic hypertension, initially raising the suspicion of pulmonary embolism, then evaluated with contrast-enhanced computed tomography (CT) scan, revealed to be a complicated AAA with extradural hematoma compressing the right branch of the PA, resulting in acute cor pulmonale.
Case report
An 82-year-old male patient was admitted for syncope followed by dyspnea; the patient was apyretic, heart rate was 107 bpm and the blood pressure was 85/30 mmHg; arterial blood gas analysis (ABG) showed hypoxia and hypercapnia, electrocardiogram (ECG) showed sinus tachycardia and deep S waves in the DI lead; blood laboratory tests revealed a d-dimer value of 6743 ng/dl and mild anemia while phlogosis indeces were in the normal limits; the patient was then evaluated by transthoracic echocardiography (TTE) which showed a right ventricular (RV) dilated cavity and reduced global systolic function with positive McConnell's sign, elevated arterial systolic pulmonary pressure with a value of 60 mmHg; TTE also showed bicuspid aortic valve due to fusion of the right coronary and non-coronary cusps with fusion raphe with associated moderate aortic regurgitation (vena contracta 0.5 cm), ascending aortic aneurysm with a maximum diameter of about 6 cm, and a mild pericardial effusion not associated with cardiac tamponade (Fig. 1); in light of the initial clinical setting (dyspnea, ECG and ABG findings) suggestive of a possible acute cor pulmonale/pulmonary embolism, the patient was assessed by venous lower limb color-Doppler echography which resulted negative for deep venous thrombosis; as this finding did not rule out a possible pulmonary embolism, we proceeded with a contrast-enhanced CT scan chest angiography; CT scan confirmed the ascending aortic and aortic arch aneurysm and ruled out the presence of thromboembolism of the pulmonary arterial branches; however, the examination showed the presence of posterior extramural ascending aorta hematoma which caused subtotal compression of the right branch of the PA (Fig. 2); CT scan also confirmed the presence of pericardial effusion with hematic density; the patient was treated with hydration and immediate transfer to the reference cardiac surgery center; there was intraoperative confirmation of complicated ruptured AAA effectively treated with replacement with a tubular prosthesis (Fig. 3); this represents a rare case of a complicated thoracic aortic aneurysm with onset setting characterized by symptoms and signs suggestive of acute cor pulmonale, secondary to alterations in the pulmonary circulation due to compression phenomena.
Fig. 1.
Transthoracic echocardiography findings: ascending aortic aneurysm with a maximum diameter of about 6 cm (a), right ventricular dilated cavity (c and d) and reduced global systolic function with positive McConnell's sign (d, white arrow), bicuspid aortic valve due to fusion of the right coronary and non-coronary cusps with fusion raphe (c) elevated arterial systolic pulmonary pressure with a value of 60 mmHg (b), small pericardial effusion (c, yellow arrow) with no sign of hemodynamic compromise (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.).
Fig. 2.
Computed tomography (CT) scan ruled out the presence of thromboembolism of the pulmonary arterial branches and showed ruptured ascending aortic aneurysm with posterior extramural hematoma causing subtotal compression of the right branch of the pulmonary artery on axial (a) and sagittal (b) view; CT scan 3D reconstruction showing posterior extension of ruptured ascending aortic aneurysm with posterior extramural hematoma; yellow arrows indicate the border between external posterior hematoma and ascending aortic wall (c).
Fig. 3.
Intraoperative confirmation of complicated ruptured ascending aortic aneurysm (a and b) effectively treated with replacement with tubular prosthesis (c).
Discussion
The term aortic disease (or aortopathy) is currently used to label both acquired and inherited diseases, and comprises aortic (thoracic and abdominal) aneurysms, including their risk of rupture or dissection. Aortic diseases account for significant cardiovascular morbidity and mortality, with an incidence of aortic dissection in developed countries of 6 per 100,000 [1]. Probably related to the increasing mean age of the global population, from 1999 to 2010, the overall global death rates from aortic disease have increased from 2.49 per 100,000 to 2.78 per 100,000. This trend appears to affect developing countries more than developed ones [2]. In patients older than 65 years, TAAs are mostly based on a degenerative etiology and on an inflammatory etiology (aortitis) in most cases caused by noninfectious inflammatory and autoimmune diseases, more rarely, determined by infection [3,4]; conversely, genetic predisposition (familial or related to defined genetic disorders such as Marfan syndrome) is responsible for most of TAAs involving patients younger than 65 years; other aortic infectious diseases, aortic dissection, aortic hematoma, and large noninfectious TAAs are also potential causes.
The natural history of the disease is characterized by slow growth of the aneurysm with an associated increased risk of acute complications such as rupture or dissection; in the vast majority of cases, TAAs have an asymptomatic course usually being found incidentally in the course of diagnostic tests performed for other purposes; more rarely, compression of adjacent structures they may cause symptoms, including dysphagia (esophageal involvement), dyspnea (lung compression), hoarseness (left recurrent laryngeal nerve involvement), stridor (bronchial compression), and plethora (superior vena cava compression). Typically, the slow expansion determines the fact that symptoms are related to very large TAA. Due to the close anatomical relationship with PA, in AAA, the external compression caused by mass effect can be seen [5], and in rare cases, it may even rupture to PA by hemorrhagic infiltration along the connective tissue that lies between the two arteries determining PA occlusion in some cases [6]. Compression of the PA by TAA is rare and was reported in the literature more frequently in the prewar period when syphilitic aortitis was more prevalent. Extrinsic compression may cause pulmonary hypertension and right ventricular failure, clinically mimicking pulmonary thromboembolism. Although antibiotic use dramatically decreased the incidence of syphilis, some cases of extrinsic compression caused by syphilitic TAA are described in the literature [7,8]. The earliest possible differential diagnosis between acute aortic disease and pulmonary embolism is of crucial importance; the clinical importance of this first lies in the opposite implications that antithrombotic therapy would have for the two diseases. In keeping with the current guidelines for both conditions [9,10], echocardiography and contrast-enhanced CT scan represent the earliest/first-line diagnostic methods indicated, both for confirming/ruling out and possibly differentiating the two diseases; on the other hand, in the vast majority of cases, the two diseases have very different settings, e.g., chest pain is not the most frequent symptom in PE and dyspnea is a rare presenting symptom of aortic acute diseases [9,10]. For the reasons mentioned above, in the vast majority of cases, the typically different setting of the two diseases does not compel the clinician to differentiate those; furthermore, current guidelines, do not indicate specific tests with the purpose of early differentiation of the two diseases in the acute setting. In the case presented here, the posterior rupture of the aneurysm of the ascending aorta, not associated with chest pain in this patient, resulted in the development of an extramural hematoma which sub totally compressed the right branch without invasion of the wall or lumen. PA, resulting in clinical and instrumental elements compatible with acute right overload, thus mimicking a pulmonary embolism; note that, in this specific case, what we label as pulmonary arterial systolic pressure is, more correctly, the right ventricle systolic pressure as the value is representative of the increased RV afterload due not to the increased pulmonary vascular resistance but caused from the compression of a main pulmonary branch.
Conclusions
Pulmonary hypertension and acute right ventricle failure usually lead clinicians to suspect pulmonary embolism, especially in an acute setting. Nevertheless, the mass effect of an AAA compressing the PA must also be taken into account. The earliest possible differential diagnosis between pulmonary embolism and acute aortic disease is of crucial importance due to the opposite implications that the treatment of these two diseases has.
Funding
Not funded.
Declaration of Competing Interest
None for each of the authors.
Acknowledgments
NA.
References
- 1.Clift P.F., Cervi E. A review of thoracic aortic aneurysm disease. Echo Res Pract. 2019;7:R1–10. doi: 10.1530/ERP-19-0049. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Bossone E., Eagle K.A. Epidemiology and management of aortic disease: aortic aneurysms and acute aortic syndromes. Nat Rev Cardiol. 2021;18:331–348. doi: 10.1038/s41569-020-00472-6. [DOI] [PubMed] [Google Scholar]
- 3.Gornik H.L., Creager M.A. Aortitis. Circulation. 2008;117:3039–3051. doi: 10.1161/CIRCULATIONAHA.107.760686. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Burke A.P., Tavora F., Narula N., Tomaszewski J.E., Virmani R. Aortitis and ascending aortic aneurysm: description of 52 cases and proposal of a histologic classification. Hum Pathol. 2008;39:514–526. doi: 10.1016/j.humpath.2007.08.018. [DOI] [PubMed] [Google Scholar]
- 5.Buja L.M., Ali N., Fletcher R.D., Roberts W.C. Stenosis of the right pulmonary artery: a complication of acute dissecting aneurysm of the ascending aorta. Am Heart J. 1972;83:89–92. doi: 10.1016/0002-8703(72)90110-x. [DOI] [PubMed] [Google Scholar]
- 6.Guilmette J., Semionov A., Dennie C., Gahide G., Pressacco J., Fraser R., Cordeau M.P., Chartrand-Lefebvre C. Hemorrhagic infiltration of the aortopulmonary adventitia: a complication of acute aortic dissection. Eur J Radiol. Jan 2016;85(1):239–247. doi: 10.1016/j.ejrad.2015.11.025. Epub 2015 Nov 24. PMID: 26724672. [DOI] [PubMed] [Google Scholar]
- 7.Tomey M.I., Murthy V.L., Beckman J.A. Giant syphilitic aortic aneurysm: a case report and review of the literature. Vasc Med. 2011;16:360–364. doi: 10.1177/1358863X11417614. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Clapp B.R., Ratnatunga C.P., Nihoyannpoulos P. An unusual aorto-pulmonary communication secondary to syphilitic aortitis. Int J Cardiol. 1997;62:155–159. doi: 10.1016/s0167-5273(97)00184-8. PMID: 9431867. [DOI] [PubMed] [Google Scholar]
- 9.Konstantinides S.V., Meyer G., Becattini C., Bueno H., Geersing G.J., Harjola V.P., Huisman M.V., Humbert M., Jennings C.S., Jiménez D., Kucher N., Lang I.M., Lankeit M., Lorusso R., Mazzolai L., et al. 2019 ESC Guidelines for the diagnosis and management of acute pulmonary embolism developed in collaboration with the European Respiratory Society (ERS) Eur Heart J. 2020;41:543–603. doi: 10.1093/eurheartj/ehz405. [DOI] [PubMed] [Google Scholar]
- 10.Erbel R., Aboyans V., Boileau C., Bossone E., Bartolomeo R.D., Eggebrecht H., Evangelista A., Falk V., Frank H., Gaemperli O., Grabenwöger M., Haverich A., Iung B., Manolis A.J., Meijboom F., et al. 2014 ESC Guidelines on the diagnosis and treatment of aortic diseases: document covering acute and chronic aortic diseases of the thoracic and abdominal aorta of the adult. the task force for the diagnosis and treatment of aortic diseases of the European Society of Cardiology (ESC) Eur Heart J. 2014;35:2873–2926. doi: 10.1093/eurheartj/ehu281. [DOI] [PubMed] [Google Scholar]