In the group with low NT-proBNP level, 224 (73.9%) patients had unstable angina pectoris (UAP), while 53(17.5%) patients had non-ST-segment elevation myocardial infarction (NSTEMI), and 26(8.6%) patients had ST-segment elevation myocardial infarction (STEMI). The gene discussed is NPPB; the disease is intermediate coronary syndrome.