🫀 Heart Failure Explained For patients, a diagnosis of heart failure can be confusing. It doesn’t mean the heart has stopped or failed, but rather the heart can’t pump enough blood to meet the body’s needs. It may be due to weakened or damaged ventricles or stiffened walls that can’t fill properly. - Left-sided HF limits oxygen delivery to the body and backs up fluid in the lungs. - Right-sided HF impairs blood flow to the lungs and back of fluid, leading to venous congestion such as leg and ab