A sphygmochron anaysis presents a comparison of a patient’s systolic blood pressure profile with peer group limits, using a parametric and a non-parametric approach.
The MESOR, double amplitude and acrophase of the circadian rhythm are estimated parametrically, along with 90% prediction limits derived from similar data obtained from healthy peers of the same gender and of a similar age.
The patient’s profile is compared nonparametrically by computer to the time-specified reference limits (chronodesms).
When the patient’s profile exceeds these reference limits upward and/or downward, blood pressure excess and/or deficit is recognized. The results are integrated over a full 24-hour cycle to assess
a) the percentage time elevation, (PTE)
b) the timing when most of the excess occurs within 24 hours and
c) the extent of the excess, measured in mm Hg x h during 24 h and defined as the area delineated by the upper limit of the chronodesmic band and the patient’s profile whenever it exceeds that limit, the hyperbaric index (HBI).
On the basis of the parametric and non-parametric results, a recommendation is made regarding the need for any further follow-up or intervention.