Exhaled Volatile Organic Compounds in Ischemic Cardiomyocytes: Signatures of Oxidative Stress!

Volatile organic compounds (VOCs) reflect the homeostatic state of an organism, including that of cardiomyocytes. Ongoing alterations in cardiac muscle tissue can be detected as VOCs in exhaled breath. Traditionally, aging and the presence of atherosclerosis in the coronary arteries are associated with the development of ischemic heart disease (IHD). Pathophysiologically, IHD is characterized by an imbalance between the demand for and supply of oxygen and nutrients to cardiomyocytes. This imbalance favors oxidative stress over the antioxidant defense system, leading to the accumulation of reactive oxygen species (ROS) in cardiomyocytes. The molecular mechanisms of IHD involve the peroxidation of lipids, proteins, and nucleotides in cellular and intercellular components, particularly mitochondrial membranes. The products of peroxidation are released into the circulation and eventually reach the pulmonary circulation, where these products are exhaled as VOCs. This suggests that changes in exhaled VOCs in patients with IHD likely arise from oxidative stress within cardiomyocytes.