Overview of Morphologic ChangesInduced by the Toxic Effects of Drugson the Cardiovascular System
The cardiovascular system, due to complex intrinsic and extrinsic factors, can be influenced by a variety of drugs and chemical substances (Balazs et al., 1986a, 1986b). Agents may induce functional and structural alterations by interfering directly with highly specific biochemical processes that are essential to the integrity of heart and vascular tissue. Some agents can cause myocardial toxicity without having a direct effect on any cardiovascular processes. Substances which induce derangements in noncardiac organs such as the kidney can provoke biochemical changes (acid-base balance, electrolyte
levels) of sufficient magnitude to significantly alter normal cardiovascular activity. Also, agents whose primary therapeutic action is directed toward noncardiac tissues might also affect the cardiovascular system. Therapeutic agents can precipitate serious arrhythmias which impair cardiovascular function without associated morphologic alterations. Many other agents produce cardiac and vascular toxicity resulting in cellular damage and the description of these alterations is the subject of this review. At least 3 mechanisms have been identified by which agents cause changes in cardiovascular morphology (Balazs et al, 1986a, l986b).