MACD: An imaging marker for cardiovascular disease

Despite general acceptance that a healthy lifestyle and the treatment of risk factors can prevent the development of cardiovascular diseases (CVD), CVD are the most common cause of death in Europe and the United States. It has been shown that abdominal aortic calcifications (AAC) correlate strongly with coronary artery calcifications. Hence an early detection of aortic calcified plaques helps to predict the risk of related coronary diseases. Also since two thirds of the adverse events have no prior symptoms, possibilities to screen for risk in low cost imaging are important. To this end the Morphological Atherosclerotic Calcification Distribution (MACD) index was developed. In the following several potential severity scores relating to the geometrical outline of the calcified deposits in the lumbar aortic region are introduced. Their individual as well as their combined predictive power is examined and a combined marker, MACD, is constructed. This is done using a Cox regression analysis, also known as survival analysis. Furthermore we show how a Cox regression yields MACD to be the most efficient marker. We also demonstrate that MACD has a larger individual predictive power than any of the other individual imaging markers described. Finally we present that the MACD index predicts cardiovascular death with a hazard ratio of approximately four.