What condition is characterized by a decrease in cardiac output leading to congestion?

Heart failure is characterized by a decrease in cardiac output, which ultimately leads to congestion in various parts of the body, particularly the lungs and peripheral tissues. In heart failure, the heart's ability to pump blood efficiently is compromised, often due to conditions such as hypertension, coronary artery disease, or previous myocardial infarctions. This impaired pumping mechanism results in inadequate perfusion to meet the body's needs, causing blood to back up in the circulatory system, which leads to congestion.

The congestion occurs as fluid leaks from the capillaries into surrounding tissues, resulting in symptoms such as edema, shortness of breath, and fatigue. In certain types of heart failure, like left-sided heart failure, pulmonary congestion occurs, leading to symptoms such as orthopnea and paroxysmal nocturnal dyspnea.

In contrast, conditions like hypertension primarily affect vascular resistance and do not intrinsically involve a decrease in cardiac output, while pneumonia involves inflammation in the lungs that does not directly originate from cardiac output issues, and myocardial infarction is an acute event that can lead to heart failure but is not defined by the chronic state of decreased cardiac output and congestion.