Nothing for sure here but it is an interesting study, nonetheless.
Blood Test Predicts Heart Attack Risk
Protein Measurement Linked to Risk for Strokes, Heart Attack, and Heart Failure
Jan. 9, 2007 — A simple blood test may help doctors identify heart patients who are at high risk for having heart attacks, strokes, and heart failure.
The test, which measures blood levels of a protein called NT-proBNP, was found to be highly predictive of such cardiovascular events in a study involving almost 1,000 heart patients thought to have stable coronary heart disease.
… Patients with the highest levels of the protein in their blood were eight times as likely as patients with the lowest levels to die or suffer a heart attack, stroke, or heart failure during the study. Even taking into account other risk factors such as sex, age, smoking, and cholesterol levels, there was still an increased rate of such problems.