Title:
Left Main Interposition Graft Dissection Post-Bentall Procedure: Successful Percutaneous Intervention with Peripheral Stents
Introduction:
We present a unique case of a patient who developed a dissection in short-segment interposition saphenous vein graft (SVG) extended from a redo aortic homograft into the left main coronary artery (LMCA), which was successfully treated with percutaneous coronary intervention (PCI) using peripheral stents.
Clinical Case:
We describe the case of a 67-year-old man with a history of atrial fibrillation, severe aortic valve stenosis, and ascending aortic aneurysm, for which he underwent a prior Bentall procedure. Two years post-surgery, the patient developed prosthetic valve endocarditis with extensive root abscess, necessitating debridement and redo replacement of the aortic root and valve, as well as the replacement of the mitral-aortic intervalvular fibrosa. During this intervention, the right and left coronary ostia were reconnected using short interposition SVGs to the new homograft.
The patient presented to the emergency department 1.5 years after the second operation with chest pain and increased work of breathing. EKG revealed sinus tachycardia with first-degree atrioventricular (AV) block, widespread ST segment depression, and ST elevation in aVR, suggestive of global ischemia. Laboratory findings were notable for BNP level of 2742 pg/mL (reference range: <100pg/mL) and an initial high-sensitivity troponin I level of 14 ng/L (reference range: <53 ng/L), which continued to rise to peak at 72131 ng/L. Aspirin, clopidogrel, and IV heparin were administered. Urgent coronary angiography revealed a dissection in the interposition SVG connecting the aortic homograft to the LMCA, with a resultant 90% stenosis. PCI was deferred to allow for multidisciplinary discussion.
Coronary computed tomography angiography confirmed severe focal narrowing of the interposition graft as it arose from the left coronary button, with dissection extending into the LMCA. Transthoracic echocardiography showed an ejection fraction of 50% with mild eccentric aortic insufficiency. In multidisciplinary discussion, the decision was made to proceed with PCI.
During the procedure the graft's ostium was engaged with an 8F AL1 guiding catheter. Intravascular ultrasound was used. The interposition graft and left main measured 8 mm in diameter. The lesion was pre-dilated with a 4.0x15-mm compliant balloon. Given the size of the segment, peripheral stents were used. Stent delivery required placement of a Runthrough wire in a “buddy” fashion. 8.0x18- and 8.0x15-mm Genesis peripheral stents were deployed sequentially and overlapping. TIMI flow improved from II pre-PCI to III post-PCI. The patient was discharged with clopidogrel, an oral anticoagulant and a course of aspirin.
Discussion:
This case marks the first report of a dissection of a saphenous vein interposition graft extending into the LMCA following the Bentall procedure, successfully managed with PCI utilizing peripheral stents. The Bentall procedure involves simultaneous replacement of the aortic valve and ascending aorta with a composite graft and is used in patients with aortic root pathologies. Post-Bentall procedure complications are rare, and those related to the coronaries include pseudoaneurysm formation, stenosis, and ostial dissection. Awareness of these life-threatening complications is crucial when evaluating a patient presenting with acute coronary syndrome after a Bentall procedure.