The baroreflex is a vital homeostatic mechanism that maintains blood pressure at a steady level, playing a key role in the short-term control of blood pressure.
Baroreceptors are located in major arteries and veins, and in the heart. Through their feedback mechanism, they enable the autonomic nervous system to swiftly adjust the heart rate and arterial resistance, using a rapid negative feedback loop. It minimizes fluctuations in blood pressure, keeping it close to its operational level, thus ensuring optimal delivery of oxygen to the organs.
The baroreflex sensitivity (BRS) reflects the speed with which the reflex corrects the blood pressure. It is measured routinely in various pathologies. Indeed, a high BRS means that heart rate is quickly affected by a change of pressure, and that the reflex is working well, while a reduction in BRS is a poor prognosis factor, particularly in cardiovascular diseases. It is also included in additional studies of the S7A directive on pharmacological safety studies.
Two analysis techniques are mainly used to measure the BRS: The Spectral analysis and the Sequence analysis. emka TECHNOLOGIES uses the Sequence analysis, based on the measurement of blood pressure and heart rate values for each cardiac cycle.
In order to perform a sequence analysis that provides the BRS index, the Electrocardiogram (ECG) and the blood pressure (BP) must be measured. Implantable telemetry allows for continuous and stress-free measurement of these parameters in rodents and large animals.
ecgAUTO BRS module looks for ramps of several consecutive beats where Blood Pressure (usually the systolic BP) and Beat to Beat (usually RR) Intervals both increase or both decrease. The slope of the relation between BP and RR is the index of BRS.
In addition to the BRS index, the software also provides other useful information, displayed in result tables and customizable graphics, such as:
Several steps, corresponding to experimental phases, can be defined in the protocol and are reported in the BRS module. They can be selected to be displayed on the graph on request.
ecgAUTO software is highly configurable, allowing to define:
