Author + information
- David R. Holmes Jr., MD, FACC, ACC President⁎ ()
- ↵⁎Address correspondence to:
David R. Holmes, Jr., MD, FACC, American College of Cardiology, 2400 N Street NW, Washington, DC 20037
The process of and the need for measuring things has occupied a central role in human history. The systems used have been infinitely variable, ranging from the simple (e.g., the length of a finger or the width of the hand) to ultra-precise fine microscopic dimensions, such as ångströms. Such systems have become so important that they merit designation by governmental agencies like the Bureau of Weights and Measures. Measurement systems are essential for both national and international commerce, as well as for individuals (although, in the latter case, there are potential significant problems, as witnessed by how often the bathroom scale is unfriendly on Monday mornings after holiday weekends).
There are several characteristics of ideal measurement systems: 1) they must be applicable to the object to be measured (for instance, measuring a coronary stent in kilograms would be inane); 2) they must be accurate and reproducible over the geographic range in which the measurement is performed (e.g., a gallon of milk should be the same volume in every state or region); 3) it would be ideal for the systems to be harmonized and accepted globally as reference standards, such as Greenwich Meridian Time, although such harmonization is rare; and 4) they must also be relevant, measuring something of value.
One might wonder where this discourse is heading. I like to think that if we do not know how we are doing at something, then we should not be doing it. This is especially true in the healthcare field and herein enters the concept of longitudinal data repositories (i.e., registries). While randomized clinical trials are of essential value to the field by carefully setting up studies to prospectively answer focused clinical questions (often involving new devices or pharmaceutical agents) and attempting to minimize any potential bias, they also have limitations, mainly by virtue of mandated protocols in very carefully selected populations. Registries serve a different purpose: at their best, they serve to measure what is happening in the real world of patients irrespective of whether those patients are candidates for the randomized clinical trials or not.
As is true for measurement systems in general, medical registries need to contain the important elements mentioned above to be maximally valuable. More specifically, they need to include relevant data captured on consecutive patients representing an unselected population. Data definitions also must be identical for all participants and must be complete, accurate, and adjudicated to document completeness and accuracy. The data modules should be flexible so that they can efficiently and quickly respond to changes in the field, for example, changes in a specific device or application of that device to a different patient population.
In addition, data should include both clinical and administrative short- and long-term information and should be administered by a steering committee charged with ensuring optimal accurate utilization of data as well as the ability to interrogate the data. Finally, it would be optimal for the data to be vetted, accepted, and used by regulatory agencies including the Food and Drug Administration (FDA) and the Centers for Medicare and Medicaid Services (CMS) in the process of making important decisions about safety, efficacy, approval, and reimbursement.
The Society for Thoracic Surgeons and the American College of Cardiology are working together in concert with the Duke Clinical Research Institute to develop such a measurement system for a longitudinal data repository for transcatheter aortic valve replacement (TAVR). This repository contains all of the essential elements described in the previous text. All patients undergoing TAVR will be enrolled with standardized forms that will track early and longer-term follow-up, attempting to harmonize data elements from around the world. The data will be complete, adjudicated, and scientifically accurate. This registry will be overseen by a steering committee, will play a central role in “knowing what we are doing so that we can do it better,” and will enhance our ability to identify ideal patient selection criteria and provide benchmarks associated with optimal care. Importantly, both the CMS and FDA have offered to provide input into the elements collected so that there is the potential for it to be used as a post-market surveillance tool.
How do we then put this all together? As we stated in the beginning, “the process of and the need for measuring things has occupied a central role in human history.” Nowhere in the medical field is this more important than when new therapeutic strategies are developed. For this, the transformational TAVR longitudinal data repository is well matched with the transformational technology of TAVR.
From the ACC to you!
- American College of Cardiology Foundation