2019 Scientific Sessions

Title Never Late is Better - Delayed Presentation of Coronary Obstruction after TAVR Valve Implantation Introduction Coronary obstruction after transcatheter aortic valve replacement (TAVR) is an uncommon but well acknowledged potential complication, which most often has immediate consequences. Delayed presentations of coronary obstruction (DCO) are rare and require a high suspicion for diagnosis. Revascularization management is technically challenging. Clinical Case A 70 year old female with severe symptomatic aortic stenosis had a TAVR procedure with a self-expanding Evolut CoreValve at her home institution. The procedure was reportedly uncomplicated in regards to valve deployment and subsequent hemodynamics, though the patient did develop acute heart failure symptoms the following day. Additional investigations suspected the culprit problem to be mitral regurgitation, so she was diuresed and discharged with future follow up. Ten days later, she presented to our hospital for the first time with worsening heart failure symptoms. It was now three weeks post her TAVR procedure, and our echocardiogram found reduced left ventricular ejection fraction with severely hypokinetic anterior wall segments. Despite no coronary disease on evaluation prior to TAVR, she was admitted with intentions for repeat angiography to screen for coronary injury, embolization, or obstruction. We began with pigtail catheter aortography to visualize the TAVR valve, coronary vessels, and peri-valvular or intra-valvular regurgitation. We found significant compromise to left main coronary blood flow from the native aortic valve leaflet, impinged onto the artery ostium by the prosthetic valve. Utilizing a number of guide catheters, the left main was eventually engaged with a coronary wire, which was directed to the left circumflex vessel. A microcatheter was advanced for additional navigational support, but the complex lesion still required balloon assisted tracking to cross the CoreValve frame. After a number of challenges posed by the limited size of the available tract, intravascular ultrasound was used to appropriately size a drug eluting stent, which was advanced and fully expanded. The proximal edge was across the prosthetic valve, with the stent body covering the length of the left main, and the distal edge landing into the left circumflex artery. Post-dilation was performed using a non-compliant balloon, with final angiography noting TIMI III flow. No complications occurred during this revascularization procedure. Discussion DCO presentations are infrequent, with an international multicenter registry citing an incidence rate of only 0.22% from over 17,000 TAVR cases. It occurs more frequently in those with low coronary ostia heights (<10mm) above the aortic valve annular plane, and heavy annular calcification. There are conflicting reports on whether self-expandable or balloon-expandable valves are higher risk, but valve-in-valve procedures are associated with DCO. The diagnosis has been made even more than 60 days after the implantation procedure, with cardiac arrest and/or STEMI as most frequent presentations. The vast majority involve the left coronary ostium rather than the right, and stent re-vascularization success rates are only around 70%. Pre-procedural planning with CT or 3D echocardiography, and even coronary angiography at the time of TAVR, are the most useful steps for prevention.