Test May Spot Heart Attacks Before They Happen
Blood Test Looks for Type of Cell That Breaks Away From Artery Walls
Test Finds Circulating Cells
The new test uses tiny, protein-coated magnets to pull circulating endothelial cells (CECs), which are normally rare, out of a blood sample.
Similar technology is used in a test for cancer patients. That test identifies circulating tumor cells, which are also rare. In cancer, the test is meant to help doctors and patients determine how aggressive a tumor may be or whether it is responding to treatment.
Study researcher Mark C. Connelly, PhD, director of cellular research at Veridex, the company that makes the test, declined to speculate on how much the experimental blood test might cost if it’s used for heart attacks.
Researchers gave the test to 50 patients who were having major heart attacks that could be confirmed by changes to their heart’s electrical rhythms and to key levels of enzymes that are indicators of heart damage.
They also gave the test to 44 blood donors who reported being free of any chronic disease.
Heart attack patients had levels of CECs that were more than four times higher than the levels seen in healthy blood donors.
There were other important differences, too. Under a microscope, the CECs seen in heart attack patients were larger and appeared to be stuck together in clusters, whereas the CECs in healthy people were smaller and appeared more often as single cells.
The study is published in the journal Science Translational Medicine.
Many Questions Remain
Experts who were not involved in the study say the results are intriguing, but note that much more work is needed before such a test could be used to predict heart attacks.
“This is an interesting observation, but it fails to demonstrate that finding these cellular patterns in blood during stable, asymptomatic phases of [heart] disease actually will predict the future risk of a heart attack,” says Prediman K. Shah, MD, director of the division of cardiology at Cedars-Sinai Medical Center in Los Angeles. Shah also directs atherosclerosis research at Cedars-Sinai.
“That’s a fundamental flaw of the study. Maybe that will be their next study, but that’s going to be a hard study to do,” says Shah, noting that such a study would require following thousands of patients at risk for heart attack, rather than testing people who’ve already had one.