Central Aortic Pressure Index (CAPI): Explanation and Clinical Context The Central Aortic Pressure Index (CAPI) represents the ratio of central aortic pressure to peripheral systolic pressure, reflecting the impact of arterial wave reflections and aortic stiffness on central hemodynamics.
It is calculated using peripheral systolic pressure (PSP) and augmentation index (AIx), which represents the contribution of reflected waves to systolic pressure.
CAPI is a valuable parameter for assessing arterial stiffness, cardiovascular risk, and the efficacy of antihypertensive therapies targeting central pressure.
Normal CAPI values are generally less than 1 in healthy individuals, with higher values indicating increased central pressure and arterial stiffness, associated with elevated cardiovascular risk.
Reference:
Segers P, et al. "Assessment of Central Blood Pressure: Current Status and Future Directions." Journal of Hypertension, 2009;27(8):1585-1596. doi:10.1097/HJH.0b013e32832a30f5