About Us

While medical management, transcatheter interventions, and routine heart surgery have substantially decreased the morbidity and mortality associated with heart failure, cardiac transplantation continues to be the definitive treatment for refractory disease. Unfortunately, there is a persistent and severe shortage of donor hearts for transplantation.

Heart donors must be dead. Following declaration of death, donor heart function can be assessed 1) while the heart is still in the donor, 2) after transplantation, or 3) after the heart has been removed from the donor but prior to transplantation (ex situ). When the first assessment of transplant suitability in donor hearts that are known to have marginal function or hearts that have gone through the dying process occurs following transplantation, recipient surgeons are understandably cautious and highly selective about which hearts they accept. This serves to maintain the current strict donor criteria and contributes to current low donor heart availability. Although donor hearts can be reanimated while they are still in the donor using a technique known as normothermic regional perfusion (NRP), there are significant ethical, legal, and public perception concerns surrounding restoration of donor heart function after declaration of cardiac death. These concerns limit the availability of NRP and also contribute to low transplantation rates. Given the reluctance to transplant hearts when the first assessment of donor heart transplant suitability is performed after transplantation and the ethical and legal concerns associated with reanimating the heart after the donor is pronounced dead based on cardiac criteria, it becomes clear that donor heart assessment should be done following removal from the donor but prior to transplantation. Determining donor heart transplant suitability when the heart has been removed from the donor but prior to transplantation into the recipient requires normothermic ex situ heart perfusion (NEHP). NEHP maintains normal body temperature and heart function outside of the body using heart-lung machine technology. Assessing transplant suitability after the heart is removed from the donor but before it is transplanted into the recipient is ideal because it avoids transplanting a heart that may not be able to support the recipient and eliminates the ethical and legal issues associated with restoring donor heart function after declaring death based on absent heart function. Current clinical NEHP systems cannot assess transplant suitability under the physiologic conditions that will be encountered in the recipient.

The application of NEHP has recently evolved and should dramatically expand donor heart availability and utilization. NEHP systems have the potential to prolong ex situ preservation, assess and recondition marginal hearts that would otherwise be discarded, and facilitate immunomodulation, a technique that reduces immunosuppression requirements and complications following transplantation. 

NEHP assessments of transplant suitability are ideal because they are performed after the heart is procured but before it is transplanted. This avoids transplanting a heart with unknown function and eliminates the ethical, legal, and adverse public perception issues associated with restoring heart function after declaring cardiac death. Confirmation of transplant suitability requires a device that can create ex situ physiologic conditions that are the same as those that will be subsequently encountered in the recipient. This device is called the Organ Indexing System® and donor heart transplant suitability is determined by the Intrinsic Index.

Intrinsic Index, Inc. was founded by Daniel H. Drake, MD to translate the Organ Indexing System® into clinical practice for the purpose of improving the quality and availability of donor hearts for transplantation.