A family history is a record of health information about a person and their close relatives. Having relatives with a health problem does not mean that you will develop this condition, but the chances increase. This is because families have many factors in common, including genes and often the environment and lifestyle.
Two of Kyle's brothers developed heart disease, so we can say that Kyle has a family history of heart disease.
When blood is rich in carbon dioxide it leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs. (All of which have to do with the circulatory system)
