Various conditions can affect the heart's health and function. Coronary artery disease (CAD) occurs when the arteries that supply blood to the heart become narrowed or blocked by plaque buildup. This can lead to chest pain, shortness of breath, or even heart attacks.Heart failure is another common condition in which the heart is unable to pump blood efficiently. It can be caused by underlying heart conditions, such as CAD or hypertension. Symptoms of heart failure include fatigue, shortness of breath, and fluid retention.