MI-VAD: A Unique Opportunity that will Change the Management of End-stage Heart Failure

The development of the MI-VAD pump is in response to an unmet need. Current mechanical cardiac assist devices (30% one year mortality) subject the patient to significant risks: complex intrusive design, disruption of cardiac architecture, risk of infections, negative effects of non-physiologic “continuous flow”, an inability to use in many situations, including restrictive cardiomyopathy and acute myocardial infarction. Devices which offer a permanent solution whatever the etiology of heart failure are needed, are less invasive and eventually implantable percutaneously, with no hardware outside the body and applicable to less severe heart failure (class II and III), as the present generation of devices can only really be used in end-stage class IV heart failure.

The MI-VAD pump is a pulsatile, ECG gated pump placed in the supra-valvular position. For left sided heart failure (either dilated cardiomyopathy or restrictive cardiomyopathy), the pump is placed above the aortic valve. For right-sided heart failure, the pump is placed above the pulmonary valve. Because the pump is ECG gated, it is pulsatile, and augments the heart’s natural contractility. Thus blood flow is physiologic, unlike the present commercially available continuous flow devices. The result of this is normalized systolic and diastolic cardiac function, and a decrease in the tendency to bleeding, thrombosis and infection.

The present generation device will be implanted through a mini-thoracotomy procedure, with no sternotomy. The system controller would be placed in a pacemaker-like pocket, and would also be the power source, using trans-cutaneous charging. The pump could therefore augment the left or right ventricles, and in bi-ventricular cardiac failure, two pumps could be used. We project that iwith Gen-2 and Gen-3 devices, percutaneous implantation would be possible with endovascular delivery. With increasing scope for miniaturization, this pump could be used in other vessels including the abdominal aorta and other vascular beds.