Significant progress has been made in the clinical management of a variety of cardiovascular diseases. Nevertheless, the therapeutic efficacy of the current treatment modalities for atherosclerosis and restenosis is not fully sufficient in a large proportion of patients. One of the major contributing factors is the clinical and biological heterogeneity of these still life-threatening diseases, which involve processes that we do not fully understand at the moment. Over the past decades, it has become increasingly clear that part of the gene–environmental interactions relevant for complex diseases is regulated by epigenetic mechanisms such as histone acetylation and DNA methylation. Epigenetic processes modulate gene expression patterns without modifying the actual DNA sequence and have profound effects on the cellular repertoire of expressed genes. They contribute to the expression of genes that play a key role in extracellular matrix formation, inflammation, and proliferation, processes involved in cardiovascular pathologies such as atherosclerosis and restenosis.