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1 Introduction
1.1 Biomarker—What Is Answered?
In the biomedical field, the biomarker is generally considered as a kind of bioindica-
tor, which usually obtained from patient’s bio-samples, and can be qualitatively or
quantitatively measured by the clinical assay/testing equipment [ 1 – 4 ]. There are
diverse categories of biomarkers per the source of the sample, application, assay
methods, and even the stability of biomarkers. A biomarker can be gathered from the
healthy person [ 5 ] and the sick patients’ biological sample, for example, urine,
blood, tissue biopsy specimens and so on [ 6 – 8 ]. Besides, a biomarker can be obtained
from a clinical record, a combination of laboratory and clinical tests, for example,
blood pressure, glucose and lipid components in serum, or biomarker can be gath-
ered from imaging tests (ECG, echocardiogram, cardiac CT scan). To date, from the
practical point of view, biomarker increasingly plays an important role in translating
of highly promising basic research into clinical applications from a routine diagnos-
tic test, therapy decision-making, and prognostic evaluation [ 9 – 11 ] (Fig. 3.1).
1.2 What Is an Ideal Biomarker?
Ideally, the biomarker should tightly associate with the different stages of the dis-
ease [ 12 ] or/and health status [ 13 , 14 ], the intensity, and durability of physical exer-
cise [ 15 ] such as physiological status, the stage of the diseases [ 16 ], the pathogenic
Fig. 3.1 Flowchart of biomarkers application in cardiovascular health evaluation
L. Che and D. Li