Author + information
- Scott C. Silvestry, MD∗ ()
- ↵∗Address for correspondence:
Dr. Scott C. Silvestry, Florida Hospital Transplant Institute, 2415 North Orange Avenue, Suite 600, Orlando, Florida 32789.
- heart allocation system
- heart failure
- heart transplant
- restrictive cardiomyopathy
Establishing an accurate clinical diagnosis in heart failure is important. Therapeutic options, natural history, and prognosis are based on this fundamental definition. It turns out that not just establishing but the coding and confirmation of these diagnoses are extremely important. In the new United Network for Organ Sharing (UNOS) heart allocation system (1), set to transition in 2018, lowest listing status is defined according to disease classification. In addition, although hemodynamic deterioration sets higher listing status in most cases, disease qualification in a subset of patients importantly affects transplant priority and waiting list time based on previous UNOS waiting list mortality risk. However, what happens when the diagnosis is incorrect?
In this issue of JACC: Heart Failure, Raeisi-Giglou et al. (2) examine the need for verification of heart disease and the incidence of incorrect diagnosis. The authors question the underlying assumption of accuracy in the diagnoses of a given patient’s heart disease, an assumption inherent in any allocation system for heart transplantation. They point out that the specific diagnoses may have important implications in not just the prognostic but also the classification—and by extension—the priority and waiting time for heart transplantation. In their single-center study, the authors found significant concordance in clinical and post–heart transplantation pathological diagnoses. First, the good news: the study found 82% concordance between pre-transplantation clinical diagnoses and post–heart transplantation pathology. Discordance was noted in 18%, with more than one-half of these errors due to coding/data entry mistakes. Only 8% of the total cohort had clinically derived discordant incorrect diagnoses. With an overall correctly deduced clinical diagnosis in 92% of patients, we might be satisfied. Furthermore, the most common incorrect clinical diagnoses were sarcoidosis, arrhythmogenic right ventricular dysplasia, and other causes of predominantly right-sided heart failure. In the setting of dilated cardiomyopathy, results were even better, with clinically correct diagnoses in 98%. The bad news: clerical error/data entry occurred more often than clinical errors, likely despite a system of confirmation. Lastly, Raeisi-Giglou et al. (2) importantly warn that these errors could potentially disadvantage patients in the new heart allocation system.
This study (2) points out several vulnerabilities in the new heart allocation system. The strength of the current UNOS heart allocation system, which prioritizes waiting list status predominantly according to therapy, is that therapies are evident and verifiable. As allocation evolves from therapy-based allocation to disease and physiology criteria, and ultimately to a heart allocation score, hybrid states evolve with specific vulnerabilities and bias. Raeisi-Giglou et al. (2) insightfully note that the impending allocation system has the inherent assumption of making the correct diagnoses- creating a vulnerability in difficult-to-define diseases such as sarcoidosis that has the potential to disadvantage a small subset of patients. In addition, what prevents a patient from having both pulmonary sarcoidosis and dilated cardiomyopathy from distinct etiology? How can one prove diagnosis in an ambiguous clinical case?
How can we do better? What tools should we consistently apply to achieve certainty? Tissue is not the answer, as the authors note (2). The utility of cardiac tissue before transplantation is mixed. Endomyocardial and left ventricular apical core samples predominantly demonstrated myocyte hypertrophy with and without interstitial fibrosis. These findings did not help differentiate the underlying cardiac diseases and were also associated with coding errors. Results of endomyocardial biopsies may be helpful in sarcoidosis in selected cases, but the overall utility remains limited due to sampling error and sample size.
Although the new allocation system is less than perfect, it is an improvement over the coarse 3-tier system it replaces. This new allocation includes safeguards to prevent significant disparities in similar patient acuity. Any patient with escalating heart failure/cardiac shock therapy for progressive hemodynamic decline will warrant higher waiting list status. At this point, disease definition is less important. However, the challenge of appropriately placing patients whose disease states have the potential to rapidly transition through therapies remains real in the current and upcoming UNOS heart allocation systems without a clear solution.
The authors’ unique analysis (2) highlights new vulnerabilities in the upcoming and future heart allocation systems that rely on the clinical classification of patient disease in a less than perfect world. Requiring post-transplantation verification is a possible solution, as the authors posit, but should that verification process not already be an integral part of programmatic quality assurance?
Requiring confirmatory laboratory and radiographic tests to “prove” a diagnosis may be an option, as suggested by Raeisi-Giglou et al. (2). However, strict clinical confirmation will likely be adapted because it is best practice, especially in the subset of diseases prone to mimic others such as sarcoidosis, arrhythmogenic right ventricular dysplasia, and other restrictive cardiomyopathies. Although mistakes will be made, we hope that mistakes are not an “alternative diagnosis” aiming to achieve a higher listing tier. We now have a new ethical dilemma when faced with an indeterminate diagnosis between 2 entities with asymmetrical listing status. Clinical ambiguity with unequal listing implications now raises another aspect of “gaming” in the new heart allocation system. We add this concern to previous concerns over therapeutic escalation in patients for the sole purpose of achieving a higher waiting list status, a problem that receives coverage in the medical and public media alike (3,4).
The current and new UNOS heart allocation systems represent predominantly acuity-based classification in waiting list priority. As we evolve organ allocation systems, the natural history and accurate diagnoses will become increasingly important. To meet the responsibility of correct diagnoses and allow our patients to receive the proper listing status, we must strive to be 100% accurate in our clinical and clerical efforts. To achieve this goal, we must examine, as Raeisi-Giglou et al. (2) suggest, the role of biopsy and the accuracy of certain discordant-prone diagnoses. And lastly, we must confirm the fidelity of the transplant data entry from the clinical records of the transplant patient.
We must balance administrative burden in the data requirements for effective and equitable heart allocation with the goal of having no patient disadvantaged by a disease process having an increased tendency for clinical camouflage. As Raeisi-Giglou et al. (2) note, we must work together to develop consistent definitions for cardiac diseases with respect to cardiac transplantation instead of grouping orphan diseases into a meaningless “other” category for waiting list purposes.
Lastly, the need and role for verification of clinical data, including such basics as heart failure diagnosis to ensure accuracy of UNOS listing, need to be defined. As a specialty, we must actively seek truth and feedback on our efforts at every opportunity. Not because our peers demand it but because our patients deserve it.
↵∗ Editorials published in JACC: Heart Failure reflect the views of the authors and do not necessarily represent the views of JACC: Heart Failure or the American College of Cardiology.
Dr. Silvestry has reported that he has served as a consultant and/or speaker for Abbott and Medtronic.
- 2017 American College of Cardiology Foundation
- ↵US Department of Health & Human Services. Organ Procurement and Transplantation Network. Modify adult heart allocation 2016 2nd round. Available at: https://optn.transplant.hrsa.gov/governance/public-comment/modify-adult-heart-allocation-2016-2nd-round/. Accessed October 20, 2017.
- Raeisi-Giglou P.,
- Rodriguez E.R.,
- Blackstone E.H.,
- Tan C.D.,
- Hsich E.M.
- Stevenson L.W.,
- Kormos R.L.,
- Young J.B.,
- Kirklin J.K.,
- Hunt S.A.
- ↵NPR. Should doctors game the transplant wait list to help their patients? Available at: http://www.npr.org/sections/health-shots/2016/07/24/486787474/should-doctors-game-the-transplant-wait-list-to-help-their-patients. Accessed October 20, 2017.