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Intracardiac Clots Masked by Extracorporeal Membrane Oxygenation Venous Cannula
LETTERS TO THE EDITOR
Intracardiac Clots Masked by Extracorporeal Membrane Oxygenation Venous Cannula To the Editor: The impact of coated circuits on thrombotic complications is still controversial. As reported by Sidebotham et al,1 thrombus is not unusual in patients supported with a heparin-coated extracorporeal membrane oxygenation (ECMO) circuit without systemic heparinization. In the clinical setting of mechanical circulatory support, transesophageal echocardiography plays an essential role in detecting the potential periprocedural complications, such as cannulation-related injuries, thrombosis, and infections.2 Systemic heparinization (unfractionated heparin) during ECMO support may be challenging because of the potential bleeding. In contrast, low doses of heparin may decrease the risk of bleeding by providing a more biocompatible surface in the circuit and minimizing the surface-induced complement activation and platelet dysfunction. However, thrombus formation may occur in the ECMO circuit as a potential hazard.3,4 Therefore, a systematic search for intracardiac thrombi is strongly recommended. The authors report two patients with venoarterial ECMO support in which intracardiac clots were trapped between the venous cannula and the interatrial septum.
Fig. 1. Transesophageal echocardiograms showing intracardiac clots related to the extracorporeal membrane oxygenation venous cannula. (A) The interatrial septum bulges (arrow) into the left atrium by the extracorporeal membrane oxygenation venous cannula. (B) Pullback of the extracorporeal membrane oxygenation cannula discloses the thrombus (arrow) entrapped between the septum and the tip of the cannula. (C, D) Large thrombus attached to the interatrial septum (arrow) and floating into the right atrium. LA, left atrium; RA, right atrium.
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A 71-year-old man who had undergone cardiac surgery (mitral valve repair, coronary artery bypass, and radiofrequency ablation of atrial fibrillation) developed severe biventricular dysfunction requiring inotropic support and an intra-aortic balloon pump. As the hemodynamic impairment became refractory (intra-aortic balloon pump score ⬎2), a venoarterial ECMO circuit was positioned with cannulation of the left femoral artery and right femoral vein with 17Fr and 23Fr multistage Bioline-coated cannulae (Maquet Cardiopulmonary AG, Hechingen, Germany), respectively. The second patient was a 75-year-old man admitted to an intensive care unit for mediastinitis with life-threatening hemodynamic impairment after left ventricular aneurysmectomy (Dor procedure). The treatment included inotropic support, an intra-aortic balloon pump, and a venoarterial ECMO circuit using the same cannulae and cannulation strategy. In these two cases, anticoagulation with unfractionated heparin was targeted to a 40- to 45-second partial thromboplastin time due to recent surgery. Transesophageal echocardiography, performed for daily monitoring, displayed intracardiac blood stasis and a peculiar interatrial septum bulging into the left atrium by the ECMO venous cannula (Fig 1A). Once the cannula had been pulled back (Fig 1B), a large and mobile thrombus was found attached to the atrial septum (Fig 1C, D), near the tip of the cannula (Fig 1B), and
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LETTERS TO THE EDITOR
floating into the right atrium. Subsequent and adequate anticoagulation therapy led to complete thrombus dissolution. Antonio Grimaldi, MD Silvia Ajello, MD Mara Scandroglio, MD Giulio Melisurgo, MD Chiara Gardini, MD Michele De Bonis, MD Tiziana Bove, MD Maria Grazia Calabrò, MD Giulia Maj, MD Alberto Zangrillo, MD Federico Pappalardo, MD Cardiovascular and Thoracic Department San Raffaele Scientific Institute Università Vita-Salute San Raffaele Milan, Italy REFERENCES 1. Sidebotham D, McGeorge A, McGuinness S, et al: Extracorporeal membrane oxygenation for treating severe cardiac and respiratory failure in adults: Part 2-technical considerations. J Cardiothorac Vasc Anesth 24:164-172, 2010 2. Combes A, Leprince P, Luyt CE, et al: Outcomes and long-term quality-of-life of patients supported by extracorporeal membrane oxygenation for refractory cardiogenic shock. Crit Care Med 36:1404-1411, 2008 3. Marasco SF, Lukas G, McDonald M, et al: Review of ECMO (extra corporeal membrane oxygenation) support in critically ill adult patients. Heart Lung Circ 17:S41-S47, 2008 (suppl 4) 4. Muehrcke DD, McCarthy PM, Stewart RW, et al: Complications of extracorporeal life support systems using heparin-bound surfaces. The risk of intracardiac clot formation. J Thorac Cardiovasc Surg 110:843-851, 1995
doi:10.1053/j.jvca.2011.10.007
Transesophageal Echocardiographic Examination in the Diagnosis of Bowel Ischemia Due to Thoracic Aorta Thrombosis To the Editor: The primary source of peripheral arterial embolism is cardiac in ⬎85% of cases. Owing to the newer sophisticated imaging techniques, including transesophageal echocardiography (TEE), noncardiac sources of peripheral embolism have been detected with increasing frequency. Among these noncardiac sources, the aorta has been reported to be the origin of peripheral arterial embolism in up to 5% of cases.1 This report highlights the clear value in using TEE of the heart for cardiovascular evaluation and optimization in the perioperative period. In addition, this report describes a very rare case of thoracic aorta thrombosis successfully diagnosed by TEE in the setting of a high-dependency unit.
A 51-year-old man presented in the high-dependency unit after abdominal surgery because of bowel ischemia. The intestinal ischemia was related to a superior mesenteric artery occlusion diagnosed by abdominal computed tomographic angiography. The patient’s cardiovascular and prothrombotic risk factors included a 35-year history of cigarette smoking and hypertension. During the surgery, the patient was anuric and his initial vital signs included a heart rate of 95 beats/min, a blood pressure of 75/44 mmHg, and a central venous pressure of 10 mmHg. To delineate his hemodynamic status further, TEE was implemented immediately. The TEE examination showed thrombotic material in the distal part of the thoracic aorta. The thrombus was a highly mobile, echo-dense mass protruding into the lumen of the distal thoracic aorta (Fig 1, Video 1 [supplementary video is available online]). The transthoracic echocardiographic examination also showed visible atherosclerotic intimal lesions throughout the aorta. The electrocardiogram at rest indicated a normal sinus rhythm without any pathologic findings. The serologic survey for hypercoagulability, including antithrombin III, protein C and S deficiencies, antiphospholipid antibodies, lupus anticoagulant, and anticardiolipin antibody, were negative. Thrombocytes, fibrinogen, homocysteine, and lipoprotein(a) levels were in the normal range. Postoperatively, the patient underwent anticoagulation with unfractionated heparin. A TEE examination one week after the diagnosis showed minimal residual thrombus that was resolved completely three weeks later. The mural thrombus usually is located in the abdominal aorta, but, although infrequently, it can occur in the thoracic aorta. Although most thoracic thrombi are seen with atherosclerotic disease, several other etiologies have been described, including aneurysms, dissections, trauma, malignancy, hypercoagulable states (polycythemia and antithrombin III deficiency), and systemic fungal infections.2,3 In general, the thromboembolic events are associated with an advanced age, with the thrombus arising from complex and ulcerated atherosclerotic plaques. Interestingly, the region around the left subclavian artery seems to be one of the predisposed localizations for thrombus formation.2,3 In this rare case, the visible atherosclerotic intimal lesions and the additive prothrombotic effects, such as excessive smoking,3-5 most likely are the cause of the thrombus formation in the distal part of the thoracic aorta. In the present patient, bowel ischemia was the final diagnosis. Emboli that stemmed from the thoracic aorta may have been the main reason for the occlusion of the superior mesenteric artery.5 TEE monitoring not only aided in the diagnosis of a thrombus in the thoracic aorta and explained the cause of the bowel ischemia, but also contributed to the suitable perioperative therapeutic management. Theodosios Saranteas, MD* Georgia Kostopanagiotou, MD* Fotios Panou, MD† *Department of Anesthesia and Cardiovascular Critical Care †Department of Cardiology Medical School, University of Athens Attikon Hospital of Athens, Haidari Athens, Greece
Intracardiac Clots Masked by Extracorporeal Membrane Oxygenation Venous Cannula To the Editor: The impact of coated circuits on thrombotic complications is still controversial. As reported by Sidebotham et al,1 thrombus is not unusual in patients supported with a heparin-coated extracorporeal membrane oxygenation (ECMO) circuit without systemic heparinization. In the clinical setting of mechanical circulatory support, transesophageal echocardiography plays an essential role in detecting the potential periprocedural complications, such as cannulation-related injuries, thrombosis, and infections.2 Systemic heparinization (unfractionated heparin) during ECMO support may be challenging because of the potential bleeding. In contrast, low doses of heparin may decrease the risk of bleeding by providing a more biocompatible surface in the circuit and minimizing the surface-induced complement activation and platelet dysfunction. However, thrombus formation may occur in the ECMO circuit as a potential hazard.3,4 Therefore, a systematic search for intracardiac thrombi is strongly recommended. The authors report two patients with venoarterial ECMO support in which intracardiac clots were trapped between the venous cannula and the interatrial septum.
Fig. 1. Transesophageal echocardiograms showing intracardiac clots related to the extracorporeal membrane oxygenation venous cannula. (A) The interatrial septum bulges (arrow) into the left atrium by the extracorporeal membrane oxygenation venous cannula. (B) Pullback of the extracorporeal membrane oxygenation cannula discloses the thrombus (arrow) entrapped between the septum and the tip of the cannula. (C, D) Large thrombus attached to the interatrial septum (arrow) and floating into the right atrium. LA, left atrium; RA, right atrium.
e13
A 71-year-old man who had undergone cardiac surgery (mitral valve repair, coronary artery bypass, and radiofrequency ablation of atrial fibrillation) developed severe biventricular dysfunction requiring inotropic support and an intra-aortic balloon pump. As the hemodynamic impairment became refractory (intra-aortic balloon pump score ⬎2), a venoarterial ECMO circuit was positioned with cannulation of the left femoral artery and right femoral vein with 17Fr and 23Fr multistage Bioline-coated cannulae (Maquet Cardiopulmonary AG, Hechingen, Germany), respectively. The second patient was a 75-year-old man admitted to an intensive care unit for mediastinitis with life-threatening hemodynamic impairment after left ventricular aneurysmectomy (Dor procedure). The treatment included inotropic support, an intra-aortic balloon pump, and a venoarterial ECMO circuit using the same cannulae and cannulation strategy. In these two cases, anticoagulation with unfractionated heparin was targeted to a 40- to 45-second partial thromboplastin time due to recent surgery. Transesophageal echocardiography, performed for daily monitoring, displayed intracardiac blood stasis and a peculiar interatrial septum bulging into the left atrium by the ECMO venous cannula (Fig 1A). Once the cannula had been pulled back (Fig 1B), a large and mobile thrombus was found attached to the atrial septum (Fig 1C, D), near the tip of the cannula (Fig 1B), and
e14
LETTERS TO THE EDITOR
floating into the right atrium. Subsequent and adequate anticoagulation therapy led to complete thrombus dissolution. Antonio Grimaldi, MD Silvia Ajello, MD Mara Scandroglio, MD Giulio Melisurgo, MD Chiara Gardini, MD Michele De Bonis, MD Tiziana Bove, MD Maria Grazia Calabrò, MD Giulia Maj, MD Alberto Zangrillo, MD Federico Pappalardo, MD Cardiovascular and Thoracic Department San Raffaele Scientific Institute Università Vita-Salute San Raffaele Milan, Italy REFERENCES 1. Sidebotham D, McGeorge A, McGuinness S, et al: Extracorporeal membrane oxygenation for treating severe cardiac and respiratory failure in adults: Part 2-technical considerations. J Cardiothorac Vasc Anesth 24:164-172, 2010 2. Combes A, Leprince P, Luyt CE, et al: Outcomes and long-term quality-of-life of patients supported by extracorporeal membrane oxygenation for refractory cardiogenic shock. Crit Care Med 36:1404-1411, 2008 3. Marasco SF, Lukas G, McDonald M, et al: Review of ECMO (extra corporeal membrane oxygenation) support in critically ill adult patients. Heart Lung Circ 17:S41-S47, 2008 (suppl 4) 4. Muehrcke DD, McCarthy PM, Stewart RW, et al: Complications of extracorporeal life support systems using heparin-bound surfaces. The risk of intracardiac clot formation. J Thorac Cardiovasc Surg 110:843-851, 1995
doi:10.1053/j.jvca.2011.10.007
Transesophageal Echocardiographic Examination in the Diagnosis of Bowel Ischemia Due to Thoracic Aorta Thrombosis To the Editor: The primary source of peripheral arterial embolism is cardiac in ⬎85% of cases. Owing to the newer sophisticated imaging techniques, including transesophageal echocardiography (TEE), noncardiac sources of peripheral embolism have been detected with increasing frequency. Among these noncardiac sources, the aorta has been reported to be the origin of peripheral arterial embolism in up to 5% of cases.1 This report highlights the clear value in using TEE of the heart for cardiovascular evaluation and optimization in the perioperative period. In addition, this report describes a very rare case of thoracic aorta thrombosis successfully diagnosed by TEE in the setting of a high-dependency unit.
A 51-year-old man presented in the high-dependency unit after abdominal surgery because of bowel ischemia. The intestinal ischemia was related to a superior mesenteric artery occlusion diagnosed by abdominal computed tomographic angiography. The patient’s cardiovascular and prothrombotic risk factors included a 35-year history of cigarette smoking and hypertension. During the surgery, the patient was anuric and his initial vital signs included a heart rate of 95 beats/min, a blood pressure of 75/44 mmHg, and a central venous pressure of 10 mmHg. To delineate his hemodynamic status further, TEE was implemented immediately. The TEE examination showed thrombotic material in the distal part of the thoracic aorta. The thrombus was a highly mobile, echo-dense mass protruding into the lumen of the distal thoracic aorta (Fig 1, Video 1 [supplementary video is available online]). The transthoracic echocardiographic examination also showed visible atherosclerotic intimal lesions throughout the aorta. The electrocardiogram at rest indicated a normal sinus rhythm without any pathologic findings. The serologic survey for hypercoagulability, including antithrombin III, protein C and S deficiencies, antiphospholipid antibodies, lupus anticoagulant, and anticardiolipin antibody, were negative. Thrombocytes, fibrinogen, homocysteine, and lipoprotein(a) levels were in the normal range. Postoperatively, the patient underwent anticoagulation with unfractionated heparin. A TEE examination one week after the diagnosis showed minimal residual thrombus that was resolved completely three weeks later. The mural thrombus usually is located in the abdominal aorta, but, although infrequently, it can occur in the thoracic aorta. Although most thoracic thrombi are seen with atherosclerotic disease, several other etiologies have been described, including aneurysms, dissections, trauma, malignancy, hypercoagulable states (polycythemia and antithrombin III deficiency), and systemic fungal infections.2,3 In general, the thromboembolic events are associated with an advanced age, with the thrombus arising from complex and ulcerated atherosclerotic plaques. Interestingly, the region around the left subclavian artery seems to be one of the predisposed localizations for thrombus formation.2,3 In this rare case, the visible atherosclerotic intimal lesions and the additive prothrombotic effects, such as excessive smoking,3-5 most likely are the cause of the thrombus formation in the distal part of the thoracic aorta. In the present patient, bowel ischemia was the final diagnosis. Emboli that stemmed from the thoracic aorta may have been the main reason for the occlusion of the superior mesenteric artery.5 TEE monitoring not only aided in the diagnosis of a thrombus in the thoracic aorta and explained the cause of the bowel ischemia, but also contributed to the suitable perioperative therapeutic management. Theodosios Saranteas, MD* Georgia Kostopanagiotou, MD* Fotios Panou, MD† *Department of Anesthesia and Cardiovascular Critical Care †Department of Cardiology Medical School, University of Athens Attikon Hospital of Athens, Haidari Athens, Greece