Heart failure

Four symptoms should raise alarm, particularly if they occur in combination or recently.
Shortness of breath. This is due to an increase in blood pressure in the pulmonary vessels, preventing the lungs from functioning properly. It manifests itself first as difficulty in catching one's breath when exerting oneself, then for progressively weaker efforts, and later at rest in a seated position. A cough while lying down, especially at night, may be associated. The onset of shortness of breath while lying down is a symptom of aggravation.
Edema. Swelling of certain parts of the body is cause for alarm. Oedemas appear in the lower limbs: ankles, feet or legs swell, leaving traces of finger pressure.
Weight gain. Significant weight gain (2 to 3 kg) in just a few days is abnormal and should raise the alarm.
Physical fatigue. This is due to a lack of oxygen and nutrients to the muscles. Fatigue is felt during the efforts of daily life (walking, climbing stairs, carrying a load), and leads to a reduction in physical activity and loss of muscle tone.
If you experience one or more of these symptoms, don't hesitate to consult your doctor.

https://www.ameli.fr/assure/sante/themes/insuffisance-cardiaque/symptomes-diagnotic-evolution