December 15, 2020
HeartFlow announced that a new cost-effectiveness analysis found a diagnostic pathway that utilizes coronary computed tomography angiography (CTA) with the HeartFlow FFRct Analysis to be “dominant” (less costly and more effective) as compared to stress testing for assessing patients with coronary artery disease (CAD), the leading cause of death.
HeartFlow reports these new findings were published today in JAMA Network Open.
“In the United States, more than 8.7 million symptomatic patients undergo non-invasive diagnostic testing due to suspicion of obstructive CAD each year, at an expense of $15 billion annually to the US health system. In a major change as compared to 20 years ago, relatively few of these patients (10 to 20%) have obstructive CAD but about 50% have non-obstructive CAD, which has emerged as a new and important risk factor for cardiovascular events. Test characteristics of traditional stress testing, which are still used for 95% of patients in the US, for this new mix of CAD findings are much less accurate and may result in repeat testing and inefficient use of resources or will leave CAD unrecognized in many patients,” said Udo Hoffmann, MD, MPH, senior author; Associate Chair of Imaging Sciences, Chief of the Division of Cardiovascular Imaging and Director of the Cardiovascular Imaging Research Center at Massachusetts General Hospital and Professor of Radiology, Harvard Medical School.”
He added, “The main finding of our cost-effectiveness analysis is that anatomic-based strategies, including coronary CTA alone and coronary CTA with the addition of FFRct, are more effective at patient selection for invasive angiography and coronary revascularization and at identifying patients in whom statin therapy may prolong lives. These findings support the recent guideline changes by the European Society of Cardiology but most importantly support broader adoption of this approach in the US, which will hopefully be reflected in the upcoming US guidelines for stable chest pain.”
For this cost-effectiveness analysis, the authors utilized a Markov microsimulation-model using individual patient data from the PROMISE trial to compare three diagnostic strategies: functional testing (nuclear stress testing, stress echocardiography, or exercise treadmill testing), coronary CTA alone, and coronary CTA coupled when appropriate with the HeartFlow Analysis. One strategy was considered “dominant” compared to another strategy if it provided both cost-savings as well as better clinical outcomes.
To evaluate clinical effectiveness, the authors looked at lifetime rates of heart attack and death, as well as efficiency of patient selection for invasive diagnostic coronary angiography (ICA) and revascularization, such as a stent procedure or bypass surgery. The authors found that compared to stress testing, coronary CTA with the HeartFlow Analysis improved by 50% the efficiency of selecting patients for invasive testing who then required coronary stenting or bypass procedures.
To measure cost-effectiveness, the authors looked at quality-adjusted life years (QALY) and the incremental cost-effectiveness ratio (ICER) of the three strategies. For this analysis, the authors assumed a Medicare reimbursement rate of $1450 for the HeartFlow Analysis. Patients who were diagnosed through the pathway of coronary CTA with the HeartFlow Analysis gained an additional six months of life in perfect health compared to stress testing (QALYs: 25.14 for CTA+HeartFlow, 25.15 for CTA alone, and 24.68 for stress testing) and cost $767 less compared to stress testing and $1,461 less compared to CTA alone. Over a lifetime, coronary CTA alone was cost-effective compared to stress testing (ICER $2743/QALY), and coronary CTA with the HeartFlow Analysis was “dominant” as it cost less and was more effective.
The authors also compared the three strategies to a “do nothing” strategy, in which patients only received medication, using a cost-effectiveness threshold of $100,000 per QALY. Compared to a “do nothing” strategy, the coronary CTA with HeartFlow Analysis strategy was the most cost-effective, and stress testing was of borderline cost-effectiveness (CTA + HeartFlow vs do-nothing, $36,968/QALY; CTA alone vs do-nothing, $59,436/QALY; stress testing vs do-nothing, $99,678/QALY).
“The finding that coronary CTA with the HeartFlow Analysis is ‘dominant’ compared to stress testing and more cost-effective than CTA alone reinforces what we have seen in clinical trials and clinical practice,” said Campbell Rogers, MD, FACC, Chief Medical Officer, HeartFlow. “These findings are incredibly impactful as it means the coronary CTA with HeartFlow Analysis pathway can free up valuable resources for the patients who need invasive treatment, and keep those who do not at home, while delivering clear cost savings to the healthcare system.”