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Blood test

Blood tests, also called biomarkers, play an important role in the diagnosis of myocardial infarction and myocarditis, heart failure and arteriosclerosis. White blood cell count, CPK (creatine phosphokinase), cholesterol level, blood glucose level, CRP, etc. have also been important biomarkers used since ancient times. In particular, there are tests called troponin and BNP, which are the most commonly used tests.

1. Troponin

In myocardial infarction, the muscles of the heart die. When myocardial cells fail, an enzyme called myocardial escape enzyme flows into the blood. In recent years, the troponin test can measure troponin with high sensitivity and has been widely used for rapid diagnosis of myocardial infarction (Figure 2). Depending on the size of myocardial infarction, it will be very high from 2-3 days to 5-6 days after onset. According to various reports, both sensitivity and specificity are about 90-95%, and myocardial infarction can be diagnosed with extremely high accuracy.

Figure 2. Blood test (troponin)


2. BNP

Brain natriuretic peptide is a hormone secreted by the heart ventricle. Even under normal conditions, BNP secretes a small amount, but when the heart is under pressure, BNP secretion increases. BNP is an indispensable part of the daily medical treatment of the circulatory system. 

 In Japan, a report targeting 1,098 Ningen Dock patients was said to have a high diagnostic ability with a sensitivity of 90% for detecting early heart failure and a specificity of 96%. The ability to accurately diagnose the disease is thought to be very high. There are two types of blood BNP measurement, BNP and NT-proBNP (Fig. 3). There is no significant difference in their clinical significance.

Figure 3. Blood test (BNP)

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