Heart failure symptoms often include shortness of breath, fatigue, and swelling in the legs. However, some less common signs can also indicate a weakened heart. Rapid or irregular heartbeats (palpitations or arrhythmias) can occur as your heart struggles to maintain an effective rhythm. A persistent cough that doesn't respond to treatment or worsens at night might be a sign of fluid buildup in the lungs due to heart failure.

Sudden weight gain due to fluid accumulation can be another indicator. While nausea and lack of appetite are not typical heart failure symptoms, they can sometimes occur due to reduced blood flow to the digestive system. Difficulty concentrating or feeling mentally sluggish can be caused by decreased blood circulation to the brain. Finally, frequent urination at night might be a sign of the body trying to get rid of excess fluid when lying down. If you experience any of these less common symptoms, especially in conjunction with more typical signs like shortness of breath or fatigue, consult your doctor to rule out other causes and determine if they might be related to heart failure.