The technical term is 'cardiology'.
Cardiology is an internal medicine specialty dealing with the diagnosis and treatment of disorders of the human heart.
The study of the ear is in the field of ear/ nose/ and throat. This field is called otolaryngolgy. The diseases are called otolaryngolic diseases. The doctor in this field is called and ENT doctor.
phytopathology
The study of the heart in a medical field is called cardiology. Those who study the heart are called cardiologists and should not be confused with cardiac surgeons who performs cardiac surgeries on the heart.
Physiologist.
Physiology is the study of the functions of an organism or the functions of its parts. The study of the functions of a structure is known as physiology. The study of the structure of an organism is called anatomy. (In contrast, pathophysiology is the study of abnormal functions) For example anatomy would be parts of the heart and what it looks like. Physiology would be how it works.
cardiology is the study of the function structure and diseases of the heart pulmonology deals with diseases of repository system
James Mackenzie has written: 'The study of the pulse, arterial, venous, and hepatic, and of the movements of the heart' -- subject(s): Accessible book, Pulse 'Diseases of the heart' -- subject(s): Heart, Diseases
cytology
The study of viruses and its role in diseases is called virology.
Neurology is the study of the nervous system, including the brain.
Encephalopathology is a precise, but rarely used, term meaning the study of diseases of the brain. Normally, the specialty is just called neurology.