that 46 percent of patients had a low score, and 54 percent had a high score. The results meant the most for patients who have the low score, because for them, it means that 96 percent of the time they be confident they don’t have coronary artery disease, says CardioDx chief medical officer Mark Monane.
Still, there’s a fair bit of uncertainty among those with a high score. CardioDx suggests that those with a high score go on to get a follow-up MPI test, Monane says. By layering those two tests on top of each other, doctors can hope to weed out many more patients who would otherwise get unnecessary invasive coronary procedures, he says. Even so, by adding in the CardioDx test, a majority of patients (53 percent) are still expected to get invasive procedures when they don’t have coronary blockages, Monane says.
The CardioDx test has its limits. It can’t be used in emergency situations, because it only provides an answer in a 72-hour turnaround time from the company’s Palo Alto lab. It’s an open question whether in the real world, physicians who get a low score will trust the data, and forgo further tests that add costs. And it isn’t for patients with diabetes, who already have higher coronary risks, Monane says.
But today’s findings could help CardioDx appeal to a broad group of primary care physicians and cardiologists who are looking for ways to better diagnose chest pain in a convenient way.
“We think our test is validated, it’s easy to use, it’s a blood draw, it can be done immediately, and it doesn’t require people to go out and buy an expensive piece of equipment,” Monane says.
Thomas, who is presenting the results today at the American Heart Association meeting, said there is a lot of interest among his peers in the data. But it will take time before people start actually incorporating it into their practice. He isn’t sure whether it will reduce healthcare costs, because some doctors may like the technology enough to use it on broader groups of patients than intended. Further in the future, the technology could also find additional uses, like as a monitoring tool in clinical trials to see whether drugs like cholesterol-lowering statins are working or not, he said.
“Physicians will want to see other physicians using it, and want to see it embedded in clinical guidelines,” Thomas says. “This doesn’t change medicine tomorrow, but it’s one step in potentially changing heart care.”
