Transcatheter Coronary Artery Bypass to Circumvent Iatrogenic Obstruction: The VECTOR (Ventriculo-Coronary Transcatheter Outward Navigation and Re-Entry) Procedure in Swine.

BACKGROUND

Coronary artery obstruction is a rare but devastating complication of transcatheter aortic valve replacement. Current techniques (transcatheter leaflet modification or snorkel stenting) cannot prevent obstruction in all cases.

METHODS

We created a transcatheter coronary artery bypass procedure, VECTOR (Ventriculo-Coronary Transcatheter Outward Navigation and Re-Entry), to bypass the proximal coronary artery with a covered stent graft. We tested the feasibility of creating a neo-ostium, 10 to 15 mm cephalad to the native, and bypassing the proximal coronary artery in swine. We established a proximal anastomosis using transcatheter electrosurgery to exit the aorta to the pericardium. The distal anastomosis was created using a guidewire to exit the proximal coronary artery and enter the pericardium. The points were connected, and a covered stent graft implanted to bypass the proximal vessel. Coronary angiography and intravascular ultrasound were used to assess graft patency and expansion.

RESULTS

The VECTOR technique was developed in 11 and performed on the right coronary artery in 6 additional healthy swine. Proximal and distal anastomoses were successfully created, and up to 3 (total length 40 [35-45] mm) covered stent grafts were delivered to bypass the proximal vessel. There were no significant complications. All vessels had TIMI III flow on completion.

CONCLUSIONS

Transcatheter coronary artery bypass with VECTOR is feasible in swine and may offer an effective solution to circumvent iatrogenic coronary artery obstruction following transcatheter aortic valve replacement when other transcatheter techniques are not possible.