This post was authored by former ACC President Alfred Bove, M.D., Ph.D., M.A.C.C. For more blogging from Dr. Bove, visit his blog on CardioSource Communities, which discusses the Heart and Diving.

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As I listen with my stethoscope to the chest of a patient with the Heartmate II® left ventricular assist device (LVAD), I am struck by the absence of the mechanical sounds so familiar with the prior Heartmate I® device that was a pulsatile LVAD.  Instead, there is a soft whine of the high speed rotor of the axial pump that had its origin in the fuel injectors of the rocket engines used for space flight.

The news about former Vice President Dick Cheney receiving a Heartmate II axial LVAD has raised awareness of the fact that there are now hundreds of patients who are alive, waiting for a heart transplant or living with the VAD as a permanent heart assist device.  These devices have added an important tool to our therapy of end stage heart failure.  When we used chronic inotrope infusion to keep patients stable while they waited for a heart transplant, we found a number of patient who ultimately could not maintain their cardiac output, and required an assist device that was usually an intraaortic balloon pump prior to about 1994.  

Since then we have been able to support the end stage failing heart with an assist device that is well tolerated in most patients and has been shown to extend life in these patients.  With the new design that shifted the pumping mechanism from a cyclic pump that would wear out in 12-16 months, to an axial rotating pump with specially designed bearings that last many years, longer term use of the devices became possible. There are patients in the U.S. who are living for more than 3 years with the devices.  Many return to full activity, and seem to tolerate the device quite well.  We have heart patients that ask about avoiding transplant and keeping the VAD to eliminate the need for the complex medication program and the complications of immunosuppression that occur post heart transplantation.

There are still the complications of infection, embolism, and mechanical failure that are not avoided with the new axial VADS, and the activation of Von Willebrand factor due to the high shear rate of the rotating pump.  The patients also need to be on warfarin anticoagulation.  In spite of the side effects and the care needed to avoid infection, maintain charged batteries, perform VAD failure drills, and the constant questions about what is whirring inside their chest, patients appreciate the fact that they can return to a more normal life without heart failure.  Given his circumstances, I believe Mr. Cheney made a good choice for his heart failure therapy.