For centuries, knowledge about the heart, one of the most important organs in the human body, was limited to assumptions and theories. These ideas often served as a basis for understanding the functioning of the circulatory system, but they lacked scientific confirmation. It was not until the 17th century that scientists began to conduct more detailed, although often risky, experiments that shed light on the functioning of the heart. These experiments marked the beginning of reliable insights into the functioning of the circulatory system. As medical knowledge developed, the focus shifted to the treatment of circulatory system diseases. Initially, treatment consisted of minor procedures, but advances in science and technology paved the way for groundbreaking achievements. A historic milestone occurred on December 7, 1967, when the world's first successful heart transplant was performed. This achievement revolutionized medicine, giving new hope to patients with serious heart diseases. Today, a heart transplant is often considered a treatment of last resort, saving lives when other treatments have failed and significantly reducing mortality from cardiovascular disease (Circulatory System Disease). Despite advances in medical science, cardiovascular disease remains a global health challenge, affecting about 40% of the world's population. In Poland alone, about 12 million people suffer from conditions such as hypertension, myocardial infarction, stroke or atherosclerosis. These diseases have become a major public health problem, underlining the importance of prevention, early detection and advanced treatment options to combat their prevalence and impact.