What is a major characteristic of systolic failure of the left heart?

A major characteristic of systolic failure of the left heart is the loss of contractile ability. This type of heart failure occurs when the heart muscle does not contract effectively, leading to a reduced ejection fraction during ventricular systole. In systolic heart failure, the heart is unable to pump blood out effectively, which can lead to a range of complications, including fluid accumulation and symptoms of congestion.

The impaired contractility means that the heart's ability to generate the force needed to pump blood into the aorta and subsequently to the rest of the body is diminished. This is significant because patients with systolic heart failure may present with symptoms such as shortness of breath, fatigue, and fluid retention due to the reduced cardiac output.

In contrast, other choices, while relevant to heart failure, do not specifically characterize systolic failure. Stiffness of the ventricle is more indicative of diastolic heart failure, where the heart has difficulty filling with blood due to rigid walls. Backward movement of blood into systemic circulation typically refers to right heart failure affecting systemic venous return, while high-output heart failure is a condition that occurs when the heart pumps an abnormally high volume of blood, which is not a characteristic of systolic failure.