Pilot Study of an Extra Aortic Counterpulsation Device acutely attached to the ascending aorta in the open chest for patients with hypertensive heart failure

Abstract

We propose treating hypertensive moderate heart failure by directly treating aortic stiffness (increasing aortic distensibility; increasing expansion and contraction). Our passive recoil extra aortic balloon counterpulsation device, the BioQ Cardiac Assist device (BioQ CA), reduces aortic stiffness leading to a reduction in afterload, achieving reduced pulse and mean aortic pressures in pilot animal testing by 27% and 10% respectively, and improved left coronary artery (LCA) blood flow by 39%. The device is minimally invasive, non-blood contacting, failure mode safe, and requires no pump, leads, or ECG timing, and is a cost effective approach. Additionally, the device offers the ability to adjust its performance post implantation (for future chronic studies) by changing balloon pressure via a subcutaneous inflation port. Device proof-of-principle has been established where the BioQ CA device has shown to operate as a counterpulsation device by decreasing heart load, reducing pulse and mean pressures, and improving left coronary artery blood flow. These changes are within the range of improvement achieved with pump powered Intra-Aortic Balloon Pump (IABP) and extra-aortic balloon (EAB) systems, and the blood pressure reduction achieved with renal denervation and barostim modulation, demonstrating our passive recoil counterpulsation device is competitive on performance yet with the advantages of being a simple self-powered, stand alone device, offering superior cost savings compared to other technology approaches. More recently the device was implanted in two patients in India prior to scheduled coronary artery bypass grafting (CABG). Devices were attached around the ascending aorta for approx. 30 minutes with increases in left coronary artery (LCA) blood flow of 30% to 100% measured, cardiac output improvements of up to 18%, and heart rate decreased by 8%. Patients recovered normally and were released from hospital with no adverse events. This data is very competitive and justifies further acute studies before considering a chronic human study. In this pilot study, we propose to test up to 40 patients with the device for 30 minutes on consenting patients who are scheduled for CABG. Testing will be done during vessel harvesting to minimise procedure time. We aim to measure LCA blood flow, arterial blood pressures, and cardiac output.