HeartFlow's noninvasive test for coronary artery disease cleared by FDA

A color-coded rendering of calculated FFRCT values--Courtesy of HeartFlow

The FDA gave HeartFlow de novo clearance Monday for its FFRCT technology, the first and only noninvasive imaging technology for coronary artery disease (CAD) that shows the extent of a blockage and how it affects blood flow. HeartFlow FFRCT could potentially change the way that CAD is diagnosed and managed.

The Redwood City, CA-based company focuses on noninvasive cardiovascular diagnostics and bills itself as a personalized med tech company. Its FFRCT technology combines noninvasive imaging and computational fluid dynamics technology to create detailed models of a patient's cardiovascular anatomy. It is cleared for the evaluation of patients who show signs and symptoms of CAD in conjunction with other clinical patient data.

It is both noninvasive and highly accurate, said Dr. Daniel Simon, president of the Harrington Heart & Vascular Institute at University Hospitals Case Medical Center, and Herman K. Hellerstein Chair and professor of medicine at Case Western Reserve University School of Medicine, in the release.

To use it, a physician uploads data from a coronary CT angiogram to HeartFlow's secure cloud. The HeartFlow software then analyzes the data, solving millions of equations that stimulate blood flow in the coronary arteries and calculating blood pressures around a blockage to see if it's likely to stop blood flow to the heart. The FFRCT (mathematically computed fractional flow reserve) values help physicians tailor a course of action for each patient.

While noninvasive tests to diagnose CAD are not new, studies show that they could--and should--be more accurate than they have been previously. For example, a Duke University study, published in the New England Journal of Medicine, found that less than 38% of patients who chose to undergo elective invasive cardiac catheterization and angiography were found to have obstructive coronary artery lesions, even though 84% of them had received noninvasive testing. This means that more than half of the patients surveyed underwent the invasive procedure only to find they didn't have obstructive lesions.

"FFRCT represents a tremendous advancement in the management of coronary artery disease," Simon said in the release. "Historically, we have been faced with either using tests we knew were not always accurate or putting a patient through an invasive procedure just to determine whether they needed another invasive procedure."

The clearance comes after the HeartFlow NXT study, which showed a superior discriminatory ability to identify lesions that could potentially impede blood flow when compared to the use of coronary CT angiography alone. Published in the Journal of the American College of Cardiology, the data showed that FFRCT had an 86% diagnostic accuracy, while coronary CT angiography had an accuracy of 60%.

According to MedCity News, HeartFlow was founded as Cardiovascular Stimulation Inc., in 2007, by a group of Stanford University professors. It was named to FierceMedicalDevices' Top 10 VC deals of H2 2011, having raised $65 million by year end. By mid-February 2012, the company had raised almost all of the $75 million goal for its FFRCT test.

- read the release
- read the study abstract

Special Report: Top 10 VC deals of H2 2011 - HeartFlow