Central Blood Pressure (CBP)
Aortic blood pressure
The central blood pressure (CBP) serves as a vital hemodynamic indicator, reflecting the pressure within the aorta. It is influenced by the ejected stroke volume and the dampening effect of large arteries, as well as by propagative and reflected pressure waves. Essentially, the pressure wave initiated by the left ventricle travels along the arterial tree and rebounds at various points. As a result, the pressure pattern observed at any arterial site comprises both the forward-traveling waveform generated by left ventricular contraction and the backward-traveling echo from peripheral reflection. In healthy and compliant large arteries, the reflected wave combines with the initial wave during diastole, enhancing diastolic blood pressure and facilitating coronary perfusion. Conversely, in the presence of arterial stiffness, the velocity of pulse waves increases, causing the reflected wave to merge with the initial wave during systole, elevating aortic systolic pressure rather than diastolic pressure. This scenario increases left ventricular afterload and compromises both normal ventricular relaxation and coronary filling.
One of the primary influencers of central blood pressure is arterial stiffness, which is subject to fluctuations based on both hemodynamic and non-hemodynamic factors. In comparison with conventional cuff brachial blood pressure, CBP is a better cardiovascular prognostic marker. It can be a good determinant or even preventive factor of the disease prognosis. For example, in individual’s adult with normal central blood pressure in the spurious hypertension phenomenon, which is seen in isolated systolic hypertension, the risk of organ damage can be predicted to be pretty low.
What is Central Blood Pressure and Aortic blood pressure?
Clinical studies have indicated that central blood pressure (CBP) has predictive value independent of the corresponding peripheral (brachial) blood pressure. Along with pulse pressure, they are stronger predictors of cardiovascular risk and hypertensive organ damage than brachial blood pressure.
It is crucial to employ the appropriate methodological approach and non-invasive device for assessing and interpreting both pulse pressure and central blood pressure values. For example, Central blood pressure is more relevant than peripheral pressures for understanding how cardiovascular disease develops. Furthermore, central pulse pressure is more strongly associated with vascular hypertrophy, extent of atherosclerosis, and cardiovascular events than brachial pulse pressure.
As a general reference, optimal brachial blood pressure falls within the range of 90/60mmHg to 120/80mmHg. Blood pressure is categorized as high if it reaches 140/90mmHg or above, and low if it falls below 90/60mmHg. However, it is advisable for central systolic blood pressure (SBPao) to be maintained below 140 mmHg and to be lower than brachial blood pressure.
Its calculation can be easily done using the simple Arteriograph measurement.