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The Changing Landscape in Heart Donors' Epidemiology:
Evolutionary Strategies to Avoid Extinction of the
European Heart Transplant Recipient


LUCIANO POTENA, MD, PhD
ISHLT Links International Correspondents Board Member
University of Bologna
Bologna, ITALY

luciano.potena2@unibo.it

STEVEN S L TSUI, MD, FRCS
Clinical Director of
Transplant Services
Consultant Surgeon
Papworth Hospital NHS Foundation Trust
Cambridge, UNITED KINGDOM

steven.tsui@papworth.nhs.uk

LAURENT SEBBAG, MD
Hospices Civils de Lyon
Lyon, FRANCE

laurent.sebbag@chu-lyon.fr



In the last 20 years, epidemiology of heart failure patients, along with heart transplant candidates, has changed significantly. On one hand, improved survival from acute coronary syndromes has increased the number of patients at risk for congestive heart failure. On the other hand, the availability of electric and mechanic implantable devices has prolonged disease duration of patients ultimately referred to a heart transplant program, after a long list of "conventional" strategies have failed, leading the original heart disease to a chronic systemic heart failure syndrome.

Unfortunately, the larger number of potential transplant candidates, with frequent multi-organ malfunctioning, has not been accompanied by an adequate improvement in numbers and quality of organ availability; aging of European population and reduction of fatal road accidents have resulted in a significant increase in donor age, and shift of donor causes of deaths from head trauma to ischemic and hemorrhagic strokes. This phenomenon is likely to explain, at least partially, the drop in hearts retrieved over the total number of donors utilized, and consequently, the increase in the gap between organ need and availability.

Is it possible to reverse this decline? Are transplant physicians going to become "walking shadows" waiting for organs that are likely to come later than Godot?

Among the many possible ways to face the problem, two major strategies can be drafted to increase organ availability: improve donor management to avoid heart injury and failure during organ procurement procedures in otherwise healthy hearts, and improve the acceptability of older donors by setting up diagnostic strategies to rule out subclinical heart disease. This roadmap has been followed by UK, France and Italy through three ongoing projects that represent a step forward in heart procurement policies.

UK has experienced a particularly severe reduction in the number of heart donors over the last 20 years with the annual heart transplant activity falling from over 250 to 138 per annum in 2011. Following the recommendations of an Organ Donation Taskforce, the NHS Blood & Transplant authority introduced a number of measures in 2008 to try to increase organ donation.1 These included the appointment of Clinical Leads and Specialist Nurses in Organ Donation at every intensive care unit in the country, and reimbursement to donor ICUs to cover the cost of organ donation.

Another initiative has been the introduction of Nurse Practitioners who specialise in donor assessment and donor optimisation to accompany the cardiothoracic retrieval teams to the donor hospital. These Donor Care Physiologists (DCPs) or Donor Management Practitioners (DMPs) are trained to initiate invasive haemodynamic monitoring by insertion of arterial, central venous and pulmonary artery floatation catheters, optimise fluid and inotropic management, and optimisation of lung ventilation which may include adjusting the ventilator settings and replacement of the endotracheal tube.

Recently, an Extended Donor Care Bundle has been ratified by NHS Blood & Transplant and will be introduced to all ICUs across the country, along the guidelines of the Crystal City donor consensus conference.2 To ensure that this Donor Care Bundle is applied consistently and to a high standard, a member of the cardiothoracic retrieval team will travel to the donor hospital ICU as soon as a potential cardiothoracic donor has been identified, and assist with its delivery. This "scout" from the cardiothoracic retrieval team can be a surgeon, an anesthetist or a DCP/DMP who is familiar with the nationally agreed donor care protocol. It is hoped that these measures will allow us to increase and maximize the number and quality of donor hearts available in the UK.

France and Italy, on the other hand, pursued the strategy of scratching the barrel of donor age postulating that once coronary disease has been ruled out, the heart may be adequate for donation, regardless of donor age.

Six months ago, the French Agence de la Biomédecine launched a prospective multicenter French cohort study across 159 harvest centers, designed systematically to screen using coronary angiography a large number of potential extended criteria donors. The primary objective of the study is to assess whether mandatory coronary angiography may increase donor pool. Secondary objectives are to evaluate the impact of coronarography-base procurement on transplant results in France (Primary graft failure, 1 mo and 1 year survival, cardiac allograft vasculopathy at 1 year) and evaluate coronary disease prevalence and risk factors in extended criteria donors. Two strategies are compared: a) mandatory coronarography for donors with extended criteria donor (donors from 48 harvesting centers that guarantee H24 angiography availability); b) coronarography performed only based on local availability upon request of transplant center (111 harvesting centers, with "on-demand" angiography). Extended criteria donors have been defined as: male donors 56 to 70 year old, or 51 to 55 years old with one additional risk factor excluding gender and age, or 45 to 55 years old with at least two cardiovascular risk factors excluding gender and age; female donors 61 to 70 years old, or 56 to 60 years old with one additional risk factor excluding age, or 45 to 55 years old with at least two cardiovascular risk factors excluding age. Cardiovascular risk factors are: ongoing smoking or less than three years smoking weaning, diabetes, hypertension, family history of cardiovascular disease, hyperlipidemia, ischemic stroke as donor cause of death, history of vascular disease.

Total inclusion should approximate 500 extended criteria donors. Data will be retrieved from national database; questionnaires will be filled by dedicated research assistant. Donor angiography and 1 year post transplant recipient angiography will be read centrally and scored for CAV according to ISHLT grading sheets. As of August 31, 2012, 98 donors have been included in the study. 33 donors are in the mandatory coronarography group and 65 in the control group. Results will be analyzed according to the predefined protocol and should be available at the end of 2014.

Similarly, the Italian project has been focused on retrieval of older donors, but looking at functional rather than anatomical coronary artery disease in risky donors. Potential donors older than 55, or with cardiovascular risk factors, undergo adenosine stress cardiac ultrasound with assessment of stress-induced wall motion abnormalities, and of the slope of systolic pressure to left-ventricle end diastolic volume ratio.3 Ultrasound examinations are performed by trained cardiologists in selected intensive care units, and an expert web-based supervision is available through the network of the Institute of Clinical Physiology at the National Research Council in Pisa. A pivotal experience of this project has been carried out in Bologna and Siena, showing a reliable correlation between abnormal stress ultrasound and pathological examination of the procured but not transplanted heart4, and between normal stress ultrasound and successful transplanted hearts.5 The National Transplant Center has endorsed the project and is setting up a national network to increase safe procurement of older donor hearts.

These projects are likely to be successful in improving the awareness for adequate donor management and in slowing the reduction of retrieved hearts. But their real success will be to represent the knots of a new network concept across European countries, aiming to build shared quality standards to improve not only donor management and retrieval, but also donor-recipient match. This changing landscape will be debated in a hot pre-meeting symposium which will open the next ISHLT sessions in Montréal (The Changing Landscape in Heart Transplantation: Surviving in the New Age, Wednesday, April 24, 8:00 am6) and hopefully will foster the development of international consensus.



Disclosure Statements: The authors have no conflicts of interest to disclose.

References:

  1. http://www.dh.gov.uk/en/Publicationsandstatistics/Publications/PublicationsPolicyAndGuidance/DH_082122
  2. Zaroff et al. Circulation. 2002; 106: 836-841.
  3. Grosu A, Eur Heart J 2005; 26: 2404.
  4. Leone O, J Heart Lung Transplant. 2009;28(11):1141-9.
  5. Bombardini T, J Am Soc Echocardiogr. 2011 Apr;24(4):353-62.
  6. http://www.ishlt.org/ContentDocuments/2013_ScientificProgram.pdf