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Paradoxical Peripheral Embolism – a Rare and Underestimated Event
EJVES Extra (2009) 17, 36e38
SHORT REPORT
Paradoxical Peripheral Embolism e a Rare and Underestimated Event J. Carvalho*, J.A. Pinto, J.C. Vidoedo, J. Tenreiro, R. Albuquerque Angiology and Vascular Surgery Department, University Hospital S Joa˜o, Porto, Portugal Submitted 17 August 2008; accepted 3 December 2008
KEYWORDS Paradoxical embolism; Patent foramen ovale; Acute ischaemia
Abstract We present a case of paradoxical peripheral embolism related to a patent foramen ovale (PFO) in a young female with clinical signs of pulmonary embolism and simultaneous left hand acute ischaemia. A PFO associated with a right-to-left pressure gradient was revealed by trans-oesophageal echocardiography. She underwent a successful bilateral brachial thromboembolectomy with cerebral protection by clamping of the right common carotid and simultaneous proximal right common carotid thrombo-embolectomy, according to prior angiographic study. Paradoxical embolism is still rarely considered as a possible cause of acute limb ischaemia and may be underestimated. ª 2008 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.
Case Report A 22-year-old female was admitted to the emergency room with acute onset of shortness of breath, chest tightness and nausea. She also complained of numbness and coldness of her left hand, which was pale, cold and with no palpable subclavian, brachial or distal pulses. The patient was morbidly obese (BMI Z 44.9) and had suffered an ankle injury, which had forced her to stay in bed for the previous 2 weeks. She had started oral contraceptives 2 months earlier. DOI of original article: 10.1016/j.ejvs.2008.12.007. * Corresponding author. Angiology and Vascular Surgery Department, Hospital S Joao, Av Republica, 105 e 4 Dt A, 4450-241 Matosinhos, Portugal. Tel.: þ351 966766199. E -m a i l a d dr e ss : j o a n a p a t r i c i a c a r v a l h o @ h o t m a i l . c o m (J. Carvalho).
She was alert on admission and her blood pressure was 131/77 mm Hg in her right arm and 74/53 mm Hg on the left; pulse was regular at 122 beats min1 and respiratory rate was 32 bpm. Pulmonary and cardiac auscultations were unremarkable. A hypocapnic hypoxia was revealed by arterial blood gases analysis. Electrocardiogram showed constant sinus rhythm. Multifocal pulmonary artery embolisation was confirmed by spiral CT scan, although duplex ultrasonography failed to reveal signs of deep vein thrombosis of the lower or upper extremities. She was admitted to an intermediate care unit and started systemic anticoagulation therapy with unfractionated heparin. Angiography showed left subclavian artery occlusion and a non-occlusive thrombus on the innominate artery, with extension to the right common carotid artery. The simultaneous pulmonary embolism and acute limb ischaemia, in the absence of an obvious left-side emboligenous source, lead to the diagnosis of paradoxical
1533-3167/$34 ª 2008 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ejvsextra.2008.12.001
Paradoxical Peripheral Embolism embolism (Fig. 1). The trans-oesophageal echocardiography (Fig. 2) supported this possibility by showing a small patent foramen ovale (PFO) and a right-to-left pressure gradient due to pulmonary hypertension (systolic PAP 70 mm Hg). An extensive thrombus in the descending thoracic aorta was also revealed. It excluded a cardiac source of embolisation. The patient underwent bilateral brachial thromboembolectomy. Previously to the brachial embolectomy, a right common carotid approach was performed in order to protect cerebral circulation by clamping of this vessel. A proximal carotid thrombo-embolectomy was then successfully achieved. There were no neurological deficits postoperatively and both radial pulses were palpable and symmetrical. Recovery was uneventful and she was discharged on the 12th postoperative day on long-term oral anticoagulation (target INR 2-3). On 8th month follow-up visit, she was asymptomatic. An angio-CT scan and echocardiography showed no thrombus either in the aorta or any of its branches. The prothrombotic study revealed that she was heterozygotic for factor V Leiden as well as for MTHFR (5,10-methylenetetrahydrofolate reductase) gene mutation and we decided to maintain anticoagulation indefinitely.
Discussion The inability to identify a source of embolisation in a patient without atherosclerotic risk factors is extremely common. Paradoxical embolism, which can be described as
37
Figure 2 Trans-oesophageal echocardiography e longitudinal section of aortic thrombus.
the passage of venous or right-sided cardiac thrombus into the arterial circulation, is most frequently associated with a PFO. It is rare and accounts for only about 2% of all cases of systemic arterial emboli.1 The diagnosis of paradoxical embolism can be made according to varying degrees of likelihood, being termed definitive only when made at autopsy or when thrombus is seen crossing an intracardiac defect during the radiological imaging. To consider a presumptive diagnosis, as in the present report, all the following criteria are required: (1) unexplained arterial embolus; (2) a right-to-left shunt at some level and (3) venous thrombosis and/or pulmonary embolus.2 The diagnosis of paradoxical embolism can, at best, be possible when an unexplained arterial embolus is detected in the presence of a PFO. In the present case, systemic anticoagulation was used as the mainstay of therapy, providing treatment for pulmonary embolism and prophylaxis for further thromboembolic events. The PFO closure was not performed since the foramen was small, there were no signs of pulmonary hypertension on follow-up echocardiography and the periprocedural risks are important. The high prevalence of clinically silent venous thrombosis and the presence of a PFO in up to 35% of the general population suggest that paradoxical embolism may be the cause of an acute ischaemic event (peripheral or cerebral) more often than is actually considered.3 This case highlights this uncommon presentation and alerts to this diagnostic possibility that should be considered whenever unexplained arterial occlusion occurs, particularly in younger patients.
Acknowledgements To Dr Maria Celeste Carvalho and Dr So ´nia de Carvalho for helping on English grammar reviews.
Conflict of Interest Figure 1
Angiography.
The authors declare no conflict of interest.
38
References 1 Montessuit M, Pretre R, Bruschweiler I, Faidutti B. Screening for patent foramen ovale and prevention of paradoxical embolus. Ann Vasc Surg 1997 Mars;11(2):168e72.
J. Carvalho et al. 2 Travis JA, Fuller SB, Ligush J, Plonk GW, Geary RL, Hansen KJ. Diagnosis and treatment of paradoxical embolus. J Vasc Surg 2001 Nov;34(5):860e5. 3 Chaikof EL, Campbell BE, Smith RB. Paradoxical embolism and acute arterial occlusion: rare or unsuspected? J Vasc Surg 1994 Sep;20(3):377e84.
SHORT REPORT
Paradoxical Peripheral Embolism e a Rare and Underestimated Event J. Carvalho*, J.A. Pinto, J.C. Vidoedo, J. Tenreiro, R. Albuquerque Angiology and Vascular Surgery Department, University Hospital S Joa˜o, Porto, Portugal Submitted 17 August 2008; accepted 3 December 2008
KEYWORDS Paradoxical embolism; Patent foramen ovale; Acute ischaemia
Abstract We present a case of paradoxical peripheral embolism related to a patent foramen ovale (PFO) in a young female with clinical signs of pulmonary embolism and simultaneous left hand acute ischaemia. A PFO associated with a right-to-left pressure gradient was revealed by trans-oesophageal echocardiography. She underwent a successful bilateral brachial thromboembolectomy with cerebral protection by clamping of the right common carotid and simultaneous proximal right common carotid thrombo-embolectomy, according to prior angiographic study. Paradoxical embolism is still rarely considered as a possible cause of acute limb ischaemia and may be underestimated. ª 2008 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.
Case Report A 22-year-old female was admitted to the emergency room with acute onset of shortness of breath, chest tightness and nausea. She also complained of numbness and coldness of her left hand, which was pale, cold and with no palpable subclavian, brachial or distal pulses. The patient was morbidly obese (BMI Z 44.9) and had suffered an ankle injury, which had forced her to stay in bed for the previous 2 weeks. She had started oral contraceptives 2 months earlier. DOI of original article: 10.1016/j.ejvs.2008.12.007. * Corresponding author. Angiology and Vascular Surgery Department, Hospital S Joao, Av Republica, 105 e 4 Dt A, 4450-241 Matosinhos, Portugal. Tel.: þ351 966766199. E -m a i l a d dr e ss : j o a n a p a t r i c i a c a r v a l h o @ h o t m a i l . c o m (J. Carvalho).
She was alert on admission and her blood pressure was 131/77 mm Hg in her right arm and 74/53 mm Hg on the left; pulse was regular at 122 beats min1 and respiratory rate was 32 bpm. Pulmonary and cardiac auscultations were unremarkable. A hypocapnic hypoxia was revealed by arterial blood gases analysis. Electrocardiogram showed constant sinus rhythm. Multifocal pulmonary artery embolisation was confirmed by spiral CT scan, although duplex ultrasonography failed to reveal signs of deep vein thrombosis of the lower or upper extremities. She was admitted to an intermediate care unit and started systemic anticoagulation therapy with unfractionated heparin. Angiography showed left subclavian artery occlusion and a non-occlusive thrombus on the innominate artery, with extension to the right common carotid artery. The simultaneous pulmonary embolism and acute limb ischaemia, in the absence of an obvious left-side emboligenous source, lead to the diagnosis of paradoxical
1533-3167/$34 ª 2008 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ejvsextra.2008.12.001
Paradoxical Peripheral Embolism embolism (Fig. 1). The trans-oesophageal echocardiography (Fig. 2) supported this possibility by showing a small patent foramen ovale (PFO) and a right-to-left pressure gradient due to pulmonary hypertension (systolic PAP 70 mm Hg). An extensive thrombus in the descending thoracic aorta was also revealed. It excluded a cardiac source of embolisation. The patient underwent bilateral brachial thromboembolectomy. Previously to the brachial embolectomy, a right common carotid approach was performed in order to protect cerebral circulation by clamping of this vessel. A proximal carotid thrombo-embolectomy was then successfully achieved. There were no neurological deficits postoperatively and both radial pulses were palpable and symmetrical. Recovery was uneventful and she was discharged on the 12th postoperative day on long-term oral anticoagulation (target INR 2-3). On 8th month follow-up visit, she was asymptomatic. An angio-CT scan and echocardiography showed no thrombus either in the aorta or any of its branches. The prothrombotic study revealed that she was heterozygotic for factor V Leiden as well as for MTHFR (5,10-methylenetetrahydrofolate reductase) gene mutation and we decided to maintain anticoagulation indefinitely.
Discussion The inability to identify a source of embolisation in a patient without atherosclerotic risk factors is extremely common. Paradoxical embolism, which can be described as
37
Figure 2 Trans-oesophageal echocardiography e longitudinal section of aortic thrombus.
the passage of venous or right-sided cardiac thrombus into the arterial circulation, is most frequently associated with a PFO. It is rare and accounts for only about 2% of all cases of systemic arterial emboli.1 The diagnosis of paradoxical embolism can be made according to varying degrees of likelihood, being termed definitive only when made at autopsy or when thrombus is seen crossing an intracardiac defect during the radiological imaging. To consider a presumptive diagnosis, as in the present report, all the following criteria are required: (1) unexplained arterial embolus; (2) a right-to-left shunt at some level and (3) venous thrombosis and/or pulmonary embolus.2 The diagnosis of paradoxical embolism can, at best, be possible when an unexplained arterial embolus is detected in the presence of a PFO. In the present case, systemic anticoagulation was used as the mainstay of therapy, providing treatment for pulmonary embolism and prophylaxis for further thromboembolic events. The PFO closure was not performed since the foramen was small, there were no signs of pulmonary hypertension on follow-up echocardiography and the periprocedural risks are important. The high prevalence of clinically silent venous thrombosis and the presence of a PFO in up to 35% of the general population suggest that paradoxical embolism may be the cause of an acute ischaemic event (peripheral or cerebral) more often than is actually considered.3 This case highlights this uncommon presentation and alerts to this diagnostic possibility that should be considered whenever unexplained arterial occlusion occurs, particularly in younger patients.
Acknowledgements To Dr Maria Celeste Carvalho and Dr So ´nia de Carvalho for helping on English grammar reviews.
Conflict of Interest Figure 1
Angiography.
The authors declare no conflict of interest.
38
References 1 Montessuit M, Pretre R, Bruschweiler I, Faidutti B. Screening for patent foramen ovale and prevention of paradoxical embolus. Ann Vasc Surg 1997 Mars;11(2):168e72.
J. Carvalho et al. 2 Travis JA, Fuller SB, Ligush J, Plonk GW, Geary RL, Hansen KJ. Diagnosis and treatment of paradoxical embolus. J Vasc Surg 2001 Nov;34(5):860e5. 3 Chaikof EL, Campbell BE, Smith RB. Paradoxical embolism and acute arterial occlusion: rare or unsuspected? J Vasc Surg 1994 Sep;20(3):377e84.