Marc Andreessen famously proclaimed that “software is eating the world,” in the sense that software keeps offering more services that were once delivered by professionals.
HeartFlow, Inc., a startup out Redwood City, CA, has developed software that wants to eat the cardiology world, at least the invasive angiography part of it, and make invasive cardiologists eat their hearts out.
Jokes aside, HeartFlow offers a brilliant solution to interpreting data that’s already available for many patients: standard cardiac CT scans. The company’s proprietary HeartFlow FFRCT software offers fractional flow reserve analysis derived directly from coronary CT angiograms. (HeartFlow technology received the European CE Mark in 2011 and FDA clearance in 2014.)
So the big idea is that in patients who are stable and who have an intermediate risk of coronary artery disease (CAD), the company’s software offers the same or better level of analysis in identifying areas of stenosis as invasive coronary investigations. Putting such patients through a CT instead of the cath lab should save money and be better for patients.
Medgadget had an opportunity to interview HeartFlow’s Chief Medical Officer, Dr. Campbell Rogers. Dr. Rogers was previously Chief Scientific Officer at Cordis and prior to that served as the Director of the Cardiac Cath and Experimental CV Labs at Brigham and Women’s Hospital in Boston.
Medgadget: Dr. Rogers, can you describe to our readers the practical steps of how a cardiology group can set up your service? What hardware and software is needed to get CT scans to you and receive back the analyses?
Dr. Campbell Rogers: The process of enabling a site to receive HeartFlow analyses is easier than many think. It involves setting up a virtual machine to allow the transfer of data. The beauty of this is that no hardware or capital expenditure is required. For a HeartFlow analysis to be completed, a good quality scan must be provided, but HeartFlow does not require anything different than what is recommended by society guidelines. HeartFlow has an IT team that assists in setting up the virtual machine as well as a team of CT specialists that provide support to cardiologists, radiologists, and technologists. Today we accept over 90% of scans submitted to us.
Medgadget: What are the clinical implications of FFRCT, specifically how FFFRCT-guided care changes the work up pathway in patients with CAD? What are the selection criteria?
Dr. Rogers: In current practice a number of non-invasive diagnostic tests are available to help diagnose patients with suspected coronary artery disease. The problem is that these tests are not very accurate. As a result patients often undergo multiple tests before either being referred for invasive angiography or sent home on medical therapy. Even with all these tests, the majority of patients referred for invasive angiography do not have obstructive disease. In other words, patients undergoing invasive procedure, in retrospect, likely did not need that procedure or its associated costs, complications, and patient inconvenience. At the same time there are patients who receive an incorrect negative diagnostic test results, are sent home falsely reassured, and then are at risk for a coronary event. HeartFlow improves the diagnosis of patients with suspected disease, ensures the right patients are referred for invasive management, improving patient care and reducing costs.
As for the selection criteria, we encourage physicians to send patients who have received a CT where the functional importance of disease is indeterminate. What we see is that at most sites physicians typically send patients with 30-90% stenosis by CT.
Medgadget: The results from the prospective longitudinal PLATFORM study that looked at 1-year outcomes of FFRCT-guided care in patients with suspected CAD have just been releases in JACC (Vol. 68, No. 5, 2016 Aug 2, 2016:435) The results seem to be very encouraging. Can you tell us more about the results and their implications?
Dr. Rogers: The PLATFORM trial is a prospective clinical utility study. It considered patients with suspected disease who had been referred for invasive angiography. The use of a HeartFlow-guided strategy resulted in a 61 percent reduction in invasive coronary angiograms. 117 angiograms were cancelled and after one year none of these patients, where the invasive procedure had been cancelled, had suffered an adverse clinical event. Not surprisingly, the overall cost of care decreased immediately and significantly. Initial costs decreased by 33% and the savings increased over one-year follow-up.
Medgadget: It seems to us that clinicians are generally wary of proprietary software solutions. What we mean is that without knowing how the software interprets the data, clinicians are not fully comfortable putting their trust into results delivered by a computer. How do you convince clinicians that your technology is the best there is in interpreting the complexity of hemodynamic CT data?
Dr. Rogers: HeartFlow requires the application of complex yet well-established governing principles of computational fluid dynamics. HeartFlow does not intend to keep these processes a secret, but for a HeartFlow analysis to be accurate, processes must be standardized and these computational principles must be applied appropriately. The underpinnings of this technology were developed first at Stanford and then refined over the past several years. Before receiving FDA clearance HeartFlow completed three validation studies using three sequentially improved versions of the software. These studies demonstrated the accuracy of HeartFlow’s technology. Today more than 7000 patients have received a HeartFlow analysis. As HeartFlow continues to receive data and gain experience, the process and technology continue to be refined, providing an ever-improving solution for patients with suspected disease.
Medgadget: Is the company happy with the rate of adoption of its services in the US? What are the factors and bottlenecks that prevent wider adoption of your service in the US?
Dr. Rogers: After several years of development, these are exciting times for HeartFlow. Now clinically approved in the US, Canada, Japan, and Europe, we see growing adoption of HeartFlow’s technology. Just over the past six months several sites in the US have begun to publish their real world experience. Physicians are reporting inspiring improvements in patient care and significant reductions in cost.
At the moment, a significant challenge for HeartFlow’s expansion is limited reimbursement. Very recently a handful of medical payers, including Wellmark, Blue Cross Blue Shield of Nebraska, and Priority Health have provided access for HeartFlow analysis to their beneficiaries. Growing payer support will be a key component in making this service available to those in need. It is critical that we work together with other stakeholders including physicians, patients, and professional societies to make this possible.
Medgadget: We understand that your software received favorable draft guidance from the UK’s National Institute for Health and Care Excellence. How is the company’s progress in Europe? What are the challenges?
Dr. Rogers: We are impressed by the thorough work that NICE has done in reviewing HeartFlow’s technology. NICE has now completed their assessment of HeartFlow from clinical and economic perspectives. While the final guidance has not yet been released, we have been impressed by NICE’s rigor and their leadership in the UK market. We anticipate that the NICE review of HeartFlow’s technology will be complete and publicly available in early 2017. We also have significant uptake on the continent, especially in Scandinavia.
Link: HeartFlow…