What are the signs and symptoms of left sided heart failure due associated with decreased cardiac output?

Congestion: Breathlessness, especially with exertion. Easy fatigability. Impaired exercise capacity. These are early signs. Without treatment, one becomes short of breath resting, especially when lying down (orthopnea) and at night (paroxysmal nocturnal dyspnea). Eventually the right heart also fails leading to swelling (edema), abdominal fluid (ascites and effusions), and cachexia (wasting).