The most feared signs of heart failure mainly include the risk factors that cause acute attacks of heart failure or the aggravation of clinical symptoms, such as the sudden onset of severe dyspnea, sudden onset of panic attacks and chest pain, cold and flu, etc. The symptoms of heart failure may not be obvious or serious, but if the following situations occur, they may indicate the aggravation of the disease. Heart failure patients usually have a stable condition and may not have obvious or serious clinical symptoms, but if the following situations occur, it may suggest that the condition is aggravated, and it is also some of the signs that heart failure is more afraid of. 1. The patient recently suddenly appeared serious dyspnea, chest tightness with cough, cough pink foamy sputum, suggesting an acute attack of heart failure or heart failure degree of progressive aggravation, often seen in patients with left heart failure. 2. If the patient’s recent subcutaneous edema worsens, or even abdominal effusion, pleural effusion, progressive loss of appetite, accompanied by abdominal distension, liver enlargement, it suggests that the patient’s heart failure is aggravated, which is often seen in right heart failure. 3. If the patient suddenly develops obvious symptoms of panic, chest tightness and chest pain recently, and the ventricular rate increases significantly or the heart rhythm is irregular, it suggests that the patient may have rapid ventricular arrhythmia, which will aggravate the cardiac insufficiency and even cause cardiogenic shock. 4. If a heart failure patient has recently suffered from cold and flu, it may lead to aggravation of symptoms and acute exacerbation of heart failure, which needs to be treated as soon as possible. If heart failure patients have recently experienced aggravation or new onset of severe clinical symptoms, it is recommended to seek early treatment.