Description and evaluation of a ventriculo-coronary artery bypass device that provides bi-directional coronary flow

The objective of this study was to assess acute patency of a new myocardial revascularization device that connects the left ventricular cavity to a coronary artery (termed ventriculo-coronary artery bypass, VCAB) thereby providing proximal and distal blood flow from the site of the anastomosis.

A device made of expanded polytetrafluoroethylene and low density polyethylene was implanted from the base of the left ventricle to the mid left anterior descending coronary artery (LAD) in 11 juvenile domestic pigs using a beating heart approach. Flow rates were measured in the distal LAD before and after implant using ultrasonic flow techniques, and patency was assessed at explant at either 2 or 4 weeks post-implantation. Myocardial perfusion using positron emission tomography (PET) was assessed in a separate set of pigs (n=2) revascularized by VCAB 2 weeks post-implant.

Net forward flow distal to the implanted device was 73 +/- 15% of native LAD flow. PET demonstrated that the target myocardium was perfused at 85% of that seen in the remote, control myocardium. Device patency rate was 80% (4/5) at 2 weeks in one set of pigs and 83% (5/6) at 4 weeks in a second set of pigs. Histologic analysis showed formation of neointima along the extraventricular segment of the device.

This study demonstrates the promise of perfusing ischemic myocardium using a VCAB approach with a device that provides blood flow both proximal and distal to the anastomosis. Patency of the transmyocardial device was encouraging at 2 and 4 weeks and warrants further investigation.