Cardiology is a branch of medicine that specializes in diagnosing and treating diseases of the heart, blood vessels, and circulatory system. It is considered a branch of internal medicine concerned specifically with disorders of the heart. Cardiologists are specially trained in diseases and conditions of the heart including coronary artery disease, heart rhythm problems, and heart failure.
Nephrology is another subspecialty of internal medicine that focuses on the diagnosis and treatment of diseases of the kidney. Because the kidney performs so many critical functions nephrologists maintain expertise in primary kidney disorders, but also the management of the systemic consequences of kidney dysfunction.
Pulmonology is a medical specialty that deals with diseases involved the respiratory tract. It is considered a branch of internal medicine, and is related to intensive care medicine. Pulmonologists are specially trained in diseases and conditions of the chest, particularly pneumonia, asthma, tuberculosis, emphysema, and complicated chest infections.