Successful Interventional Treatment of a Retrosternal Pseudoaneurysm of the Ascending Aorta with an Amplatzer Vascular Plug II

ABSTRACT: Pseudoaneurysm of the aorta is a rare, but potentially dangerous complication after cardiac surgery, trauma or infective aortitis. Potential fatal risk of rupture with severe hemorrhage exists, so that treatment is necessary. Surgical management carries a high morbidity and mortality rate. Using an endovascular transcatheter method seems to be a promising option for treatment of aortic pseudoaneurysms. We report a case of ascending aortic pseudoaneurysm, which was diagnosed 11 years after cardiac surgery and treated successfully by implantation of an Amplatzer Vascular Plug II. J INVASIVE CARDIOL 2010;22:E44–E46 Case report. A 74-year-old male patient underwent coronary artery bypass surgery and simultaneous aortic valve replacement (SJM 23 mm) in 1997. No major complications occurred at that time and he recovered well after surgery. Eleven years later he was admitted to the hospital due to new onset of atrial fibrillation, which converted into sinus rhythm under antiarrhythmic treatment. A routine chest X-ray revealed a retrosternal right-sided mass (Figure 1), which prompted further examination by computed tomography and transesophageal echocardiography. The diagnosis of a retrosternal pseudo-aneurysm of the ascending aorta was made and the patient was transferred to our clinic for further examination and therapy. The duplex sonography showed a biphasic flow in the region of the aneurysm with systolic inflow and diastolic outflow. The magnetic resonance imaging illustrated a 78 x 47 mm sized aneurysm with short neck, localized 6 cm distal from the aortic valve with 6 mm parietal thrombus formation (Figures 2A and 2B). Because of intact bypasses and alloprosthetic aortic valve and the directly retrosternal location of the pseudoaneurysm, a surgical treatment seemed to be associated with a high risk. Hence an interventional approach was contemplated. After imaging by aortic angiography the pseudoaneurysm was entered by a 5 French (Fr) Multipurpose catheter. Over an exchange wire a 6 Fr Multipurpose II guiding catheter was introduced and an 8 mm Amplatzer Vascular Plug II (AGA Medical Corp., Plymouth, Minnesota) deployed. To minimize occluder material in the ascending aorta two of the three lobes were positioned within the pseudoaneurysm and the third lobe in the aorta. A push-and-pull maneuver demonstrated a secure position and the device was released from its delivery catheter. The control aortic angiogram showed a complete occlusion of the pseudoaneurysm without any extravasation (Figure 3). On the day after intervention the patient underwent magnetic resonance imaging (MRI) including angiography, which confirmed the complete occlusion of the aneurysm. He was discharged on the third day after intervention. Three months later the patient was in good health and the control MRI reconfirmed the complete occlusion (Figure 2C). Discussion. Aortic pseudoaneurysms can be a fatal complication after cardiac surgery, they are described to occur in less than 0.5% of all cardiac surgical cases.1 Potential sites for pseudo-aneurysm formation are, for example, the aortic suture lines during an aortic valve replacement or the site of CABG insertion. Other possible locations are the cannulation site for the heart lung machine or the puncture site of the needle for intraoperative pressure measurement. Trauma and infective aortitis, e.g., Takayasu’s arteritis have also been described as causes for developing aortic pseudoaneurysm.2 Pseudoaneurysms may remain asymptomatic and later detected only as an incidental finding, as was the case with our patient. Clinical symptoms may present shortly after surgery or after an asymptomatic period of months or years. The symptoms can vary from chest pain, fever, pulsating tumor behind the jugulum, retrosternal feeling of pressure up to the dysphagia, stridor or hoarseness. Myocardial ischemia may result from compression of a coronary bypass. Diagnosis can be confirmed by CT or MRI scan or by transesophageal echocardiograpy. Treatment is recommended in all cases regardless of whether the patient is symptomatic. A mortality of 61% has been reported if the patient remains untreated.3 However, surgical management is associated with high morbidity and mortality rates as well, with reports ranging from 7.6%3 up to 60%.4 These high rates result from rupture of the pseudoaneurysm during sternotomy or surgical maneuvers leading to fatal hemorrhage. Alternative interventional methods are emerging as a promising less invasive option. Cases of excluding a pseudoaneurysm have been described by using stent grafts,5 various septal occluder systems2,6,7 or thrombin injection,8 though the latter was complicated by cerebral ischemia. In the present case, an Amplatzer Vascular Plug II was chosen for closure since the perforation in the aortic wall was very small in diameter and a stretching of the aortic wall by a delivery catheter might have caused further complications such as aortic dissection. The 8 mm Amplatzer Vascular Plug II can be delivered over a 6 Fr guiding catheter whereas most of the other devices need at least 8–9 Fr delivery catheters. Conclusion. Percutaneous closure is a viable therapeutic option for treatment of aortic pseudoaneurysms in selected patients with appropriate morphology.

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From the Heart and Diabetes Center North Rhine-Westphalia, Ruhr University Bochum, Bad Oeynhausen and Hospital Braunschweig, Germany. The authors report no conflicts of interest regarding the content herein. Manuscript submitted July 27, 2009, provisional acceptance given August 20, 2009, final version accepted September 10, 2009. Address for correspondence: Werner Scholtz, MD, Heart and Diabetes Center North Rhine-Westphalia, Department of Cardiology, Georgstr. 11, D-32545 Bad Oeynhausen, Germany. Email: akleemeyer@hdz-nrw.de

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