Dyspnea is a common symptom, and a heart failure is one of the most important preferred diagnoses of dyspnea. But it is difficult to undergo ECG, US, or other examination to diagnose a heart failure at the patient home, especially in the case of such examination was needed quickly or frequently. Rapidtip BNP and Rapidpia were invented in order to measure BNP rapidly at the patient home, or in the physician's car.