General symptoms of late-stage, or advanced, heart failure include increasing fatigue, shortness of breath, fluid retention, weight gain, and fainting, according to WebMD. Heart-specific signs are arrhythmia and blood pressure changes.
When someone with heart failure is unable to maintain the same activity level, it is a sign of a worsening condition, notes WebMD. Sometimes patients are incapable of performing their typical daily routines or exercises. Walking becomes more tiring. This is often accompanied by shortness of breath caused by fluid accumulation in the lungs. In certain cases, patients must sleep propped up with pillows in order to breathe.
A decrease in the heart's ability to pump leads to fluid retention, which cause weight gain and swelling, WebMD explains. Some patients accumulate 3 or more pounds of fluid in one day. Although fluid retention is typical in the feet and ankles, during late-stage heart failure, other body parts, including the thighs, buttocks, abdomen or hands, are affected.
Arrhythmia -- irregular, slow or fast heartbeat -- shows up when heart failure worsens, explains WebMD. Sometimes it is a side effect of the diuretic medications taken, because they cause potassium deficiency. A prescription adjustment often corrects this problem, according to WebMD.
A drop in blood pressure is often a sign that heart function is decreasing. If pressure rises, medications require modification, notes WebMD. Reduced blood pressure or arrhythmia leads to fainting in some cases. This, like the other signs, should be reported to the patient's physician.