While cardiovascular disease presents a challenge, medical management and medical devices in many instances are viable treatment options for patients. As more people are diagnosed with the disease and healthcare costs escalate, it has become increasingly important to find treatment options that can improve patient care in a cost effective manner.
One way this can be done is to provide a treatment that is ideally suited to each individual patient. There are technologies available that help physicians to do just this. An example of a technology that helps physician to better understand the severity and nature of a patient’s cardiovascular disease is Fractional Flow Reserve (FFR) measurement technology. It helps in the diagnosis and treatment by indicating the severity of blood flow blockages in the coronary arteries.
FFR provides a physiological measurement that identifies which coronary narrowings are responsible for obstructing the flow of blood to a patient’s heart muscle (called ischemia). Knowing this measurement helps physicians to determine the best course of action for his or her patient, which could range from medical management, to a stenting procedure or a coronary artery bypass graft (CABG) procedure. Specifically, if a physician determines stenting is the best course of action, FFR will help guide the physician in determining which specific lesions need a stent. Several recent studies have demonstrated that having this knowledge can improve care and also reduce costs.
How FFR measurement works:
Measurements are taken by placing the PressureWire across the lesion of interest and pharmacologically inducing maximal hyperemia, a state of maximum blood flow. In this state, the ratio of distal to proximal pressure allows the physician to physiologically determine if the narrowing is tight enough to cause ischemia. It is expressed as a fraction of the normal blood flow in an artery compared to the maximum achievable blood flow in the same artery.
- An FFR measurement of 1.0 indicates an artery with normal blood flow;
- An FFR measurement above .80 indicates that ischemia is very unlikely, as demonstrated in the FAME study; and
- An FFR measurement below .75 is 100 per cent specific in identifying that the blood flow blockage caused by the narrowing is responsible for a patient’s ischemia FFR measurement technology is also compatible with other diagnostic technologies, specifically those that provide imaging that enables the physician to see the plaque inside the arteries. Whereas FFR can be used to provide a physiological measurement that helps physicians to better identify which specific lesion or lesions are responsible for a patient’s ischemia, imaging technology (such as optical coherence tomography) OCT can optimise treatment so that physicians know where to best place the stents, and also see if stents have been correctly placed.
What we know about FFR measurement
Much of what we know about FFR measurement has been learned from the landmark fractional flow reserve vs angiography in multivessel evaluation (FAME) study. The study compared outcomes for patients whose treatment was guided by FFR to those patients whose treatment was guided only by angiography using PressureWire technology. The 12-month results, published in the January 15, 2009 issue of the New England Journal of Medicine, demonstrated that instances of major adverse cardiovascular events (MACE), including death, myocardial infarction or repeat revascularisation, were reduced by 28 per cent for patients whose treatment was guided by FFR rather than by standard angiography alone.
Two-year results from the FAME study demonstrated that patients who received FFR-guided treatment continued to experience improved outcomes over time, including a 34 per cent risk reduction in death or heart attack. Additionally, only one out of 513, or 0.2 per cent, of deferred lesions resulted in a late myocardial infarction (heart attack), which demonstrates that FFR results are reliable over time.
FFR-guided treatment was also demonstrated to be cost-saving, with a difference per patient of more than $2,000, or 14 per cent, between total health care costs for the FFR-guided group and the group treated by angiography alone after a year. The reduced health care costs were a result of reduced procedural costs, reduced follow-up costs for major adverse cardiac events and shorter hospital stays. These results were measured in the context of the US health care system.
The positive outcomes of the FAME study resulted in the level of evidence for FFR to be upgraded to an “A” from a “B” by the American College of Cardiology/American Heart Association/Society for Cardiovascular Angiography and Interventions. Level of evidence “A” is the highest level available, requiring the most clinical evidence and is awarded only when data is derived from multiple populations and multiple randomised clinical studies or meta-analyses. In the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS) 2010 guidelines on myocardial revascularisation, FFR measurement was awarded the strongest recommendation with the highest level of evidence. Additionally, the guidelines recommend measuring FFR before deciding PCI or surgery for multivessel disease.
FFR research in India
As evidenced by the FAME trial, cost effective technologies such as FFR measurement that improve patient care can make a significant difference in patient care while also help remove the resulting cost burden on health care systems. Though cost-saving results have primarily been demonstrated in the US and Europe, it is important that we also learn how the technology can help impact those in need of health care in India.
To that end, in February 2012, a study was initiated that will evaluate the incremental cost-effectiveness of FFR-guided treatment for patients with multivessel coronary artery disease in India and several other Asian countries. The analysis will also determine the potential health and budget impact that FFR-guided treatment provides. Specifically, as it relates to our own health care system, we expect to learn:
- The cost savings from using an FFR-guided approach to Percutaneous Coronary Interventions (PCI)
- Cumulative savings for the health care system annually
- Impact on health for the population undergoing PCI
The detailed analysis will be based on the results of the initial FAME study (was a randomised, prospective, multi-center trial with 1,005 patients), statistics from India’s PCI registries and from published literature.
India’s cost effectiveness study is being led by Professor Uwe Siebert, a FAME study co-author. Prof Upendra Kaul, the Executive Director and Dean Cardiology at the Fortis Escorts Heart Institute and Fortis Vasant Kunj and Dr J Balachander, Head of the Cardiology Department at the JIPMER Institute Pondicherry will also participate by validating the data modeling to ensure that the study calculations accurately represent patient experiences in India.
Similar research conducted in Europe last year revealed that FFR-guided treatment using the PressureWire technology can improve health outcomes while also delivering significant costs to health care systems. In Germany, the UK, France, Italy and Belgium, the FFR-guided approach has the potential to reduce deaths and heart attacks and save between 500€ and 950€ per patient, depending on the country.
Other important FFR research
Clinical studies have demonstrated that FFR improves patient outcomes and can reduce the cost burden on health care systems around the world.
The fractional flow reserve (FFR)-guided percutaneous coronary intervention plus optimal medical treatment vs optimal medical treatment alone in patients with stable coronary artery disease (FAME II) trial was designed to further study the role of FFR in the treatment of stable coronary artery disease by comparing percutaneous coronary intervention (PCI) guided by FFR plus optimal medical treatment (OMT) to OMT alone.
The interim analysis found that there was a significant reduction in the need for patients to urgently seek treatment at a hospital when FFR-guided assessment was used in stenting procedures in patients with coronary artery disease. This means that, patients receiving OMT alone experienced a highly statistically significant increased risk of hospital readmission and urgent revascularisation.
Given that FFR assessment showed such a strong and clear benefit to patients in the interim analysis, an independent Data Safety Monitoring Board recommended that investigators stop patient enrollment in the FAME II trial. Therefore the FAME II trial will continue following patients currently enrolled according to the trial protocol and will not enroll any new patients. Additional data are expected to be revealed later this year.
The trial’s clinical investigators noted that observations to-date regarding urgent revascularisations validates the profound role that FFR-guided therapy has in improving patient outcomes. Further, that this provides evidence that FFR should be considered the standard of care for patients with coronary artery disease.
Summary of Research
While the specific economic impact of FFR in India is the subject of ongoing clinical study, research in other countries has demonstrated its clinical and cost benefits. The original FAME trial demonstrated that FFR guidance improves outcomes in patients with stable coronary artery disease and two or three vessel disease. The FAME II trial interim analysis found that PCI is beneficial for patients with one, two and three vessel disease whose ischemia has been documented by FFR.
Companies interested in improving patient care will continue to conduct research on the benefits of clinically compelling and cost effective technologies such as FFR-guided therapy. As new technologies are developed and launched, it is important to understand the broader economic and health impact these therapies provide.