Cardiovascular diseases are the leading cause of death worldwide: among them, coronary artery disease and arrhythmias represent the most frequent pathological conditions. Similarly, the gastrointestinal disorders, that is, gastroesophageal reflux and inflammatory bowel diseases, have a high incidence in the general population. Several pieces of evidence have documented a link between cardiac and gastrointestinal disorders as they often share similar risk factors and symptoms. Furthermore, both can simultaneously occur in the same patient, thus creating problems in the correct clinical diagnosis. It is well known that gastrointestinal disorders may present with chest pain and mimic angina pectoris. In contrast, they can also unmask heart disease, such as in the case of the angina-linked ischemia. The aim of this review was to elucidate the mechanisms underlying the relationship between cardiac and gastrointestinal diseases to better understand the causal or casual character of such a linkage.