2024 Scientific Sessions

Coil Embolization of an Expanding Saphenous Venous Graft Aneurysm

Presenter

Robert Beale, MD, Weill Cornell Medical Center, New York, NY
Robert Beale, MD, Weill Cornell Medical Center, New York, NY, Ryan Hughes, MD, Department of Internal Medicine, Weill Cornell Medical Center, New York, NY and Charles Beale, MD, Charlton Memorial Hospital, Providence, RI

Keywords: Complications and Coronary

Title: Coil Embolization of an expanding Saphenous Venous Graft Aneurysm

Introduction

Saphenous Vein Graft aneurysms (SVGA) are a rare but potentially fatal complication of coronary artery bypass graft surgery. An aneurysm is defined as a focal enlargement of the vessel wall greater than one and a half times its normal diameter. Mild dilatation of a SVGA occurs in 14% of cases 5-7 years after surgery, however giant aneurysms (>4 cm) occur in <1% of all cases. A SVGA typically presents with nonspecific symptoms such as chest pain or dyspnea, however approximately one quarter of patients present asymptomatically, as an incidental finding. Furthermore, the presentation can be more sinister, with 13% of presenting with graft failure with a myocardial infarction (10%) or with rupture and tamponade (2.6%).

Clinical Case

We present an 86-year-old male with PMH of aortic stenosis s/p TAVR, CABG, ESRD, T2DM, found to have an expanding SVGA incidentally during an interval computerized topography (CT) in early 2023 for surveillance of a lung nodule. The SVGA was initially found on a CT angiogram in 2019 measuring around 4.0 cm and progressed to 5.6 X 5.2 X 4.6 cm. To characterize the SVGA, a computerized tomography angiography, redemonstrated this size and demonstrated the distal arm of the aneurysm was occluded. The proximal arm fed the mid vessel segment. The mid vessel lumen had a layering of chronic clot and contrast. Subsequent coronary angiography confirmed these findings. The STS risk for intra-operative mortality was 16.2% for surgical CABG repair, and he was thus deemed a prohibitive surgical risk. Due to the size of the aneurysm, interval progression, and surgical risk, the patient underwent coronary angiography with a coil embolization of this SVGA lesion.

In total ten detachable Terumo Azur Cx coils and four Cook Nestor coils were deployed. The last coil, an Azur cx 6mm x 17 cm coil was deployed with its distal end in the body of the aneurysm and its proximal end in the neck of the proximal segment of the SVG. In the case, a technical caveat we learned was that detachable coils such as the Azur Coil allow for confirmation of location prior to embolization. Pushable coils, such as the Nester Coil, offer less control, however are considerably cheaper.

At the end of the case there was evidence of SVGA thrombosis. The patient subsequently presented to the hospital with chest pain with negative biomarkers. CCTA confirmed thrombosis of the SVGA and the patient was discharged in 48 hours.

Discussion

SVGAs are a rare, yet not so uncommon presentation, which clinicians should consider in the differential diagnosis of patients post bypass. As interventionalists continue to expand care into an aging population of octogenarians and nonagenarians, familiarization with coil embolization may broaden ones armamentarium for care of complex coronary disease. Furthermore, in coil embolization, there remains heterogeneity in practice due to the infrequency of the procedure. Due to the paucity of data of the progression of SVGAs, a multidisciplinary heart team approach may provide the best guidance on a case-by-case basis.