The Apo A1 (Apolipoprotein A1) test measures the primary protein in HDL (“good”) cholesterol, helping assess your risk for heart disease by showing how well your body removes cholesterol, with higher Apo A1 usually meaning lower risk, useful when standard lipid tests don’t fully explain symptoms or risk. It’s a key marker for cardiovascular health, indicating HDL function and aiding in managing therapies and understanding conditions like heart attacks