Better Blood Tests Can Confirm Heart Attacks

LOS ANGELES (AP) — A new generation of blood tests can quickly and reliably show if a person is having a heart attack, very soon after the severe chest pains start. Currently, tests are not sufficiently definitive.

The newer, sensitive tests give a much better way to tell who needs help fast. Each year, 15 million people in Europe and the United States go to emergency rooms (A&E) with symptoms of a heart attack, but most are suffering from other complaints.

Those who are truly having a heart attack need to have blocked arteries cleared or opened quickly, to limit the damage to the heart muscle, caused by the lack of blood flow.

Currently Doctors have two main ways of diagnosing a heart attack. 1) They can use an electrocardiogram, or ECG, to measure the electrical activity of the heartbeat for abnormalities. Unfortunately, that test is not always conclusive and relies on the calibration of the instrument and the expertise of the operator.

2) Doctors can also use blood tests to detect elevated levels of a heart muscle protein known as troponin, this is a sign of heart muscle injury. The problem with the old troponin test is its lack of sensitivity. It takes longer to detect increased troponin levels and by that time, heart damage may have already occurred.

Greater Accuracy

In extensive test cases, the accuracy of the newer tests was 94 to 96% accurate, compared with 85 to 90% for the older tests.

Mayo Clinic cardiologist Dr. Allan Jaffe advocates using the newer tests. Several doctors said the new tests do not cost more than the older versions they are replacing, and are usually covered by insurance.

"You diagnose heart attacks faster and more accurately. You detect more people who are acctually having heart attacks and you can give them the priority they need," said Jaffe, who is independant of the studies and has no role in them.

He does agree that further studies are needed to determine if earlier detection of heart injury results in more lives being saved, but this is certainly a big step forward.