Answer
Pericarditis, an inflammation of the sac surrounding the heart, affected former Nigerian President Umaru Yar'Adua's health. Characterized by chest pain, fever, and shortness of breath, this condition can have various causes, including viral infections, autoimmune disorders, or chest injuries. Treatment may involve medications to reduce inflammation, manage fluid buildup, and address the underlying cause. If severe, pericarditis can lead to complications like cardiac tamponade, constricting the heart's function.