Chromogranin A is known as an important marker of neuroendocrine tumors. In cardiovascular medicine, however, chromogranin A measurement has only recently gained interest, since increased concentrations in the circulation are associated with risk of clinical worsening and death in patients with acute coronary syndromes or chronic heart failure. In this article, we summarize the current clinical data on chromogranin A as a biomarker in cardiovascular disease from high-risk conditions; for example, obesity, hypertension and diabetes, to overt heart failure. Biological activity of the various chromogranin A fragments, including the intact precursor itself, will not be covered in the present review. Instead, we highlight the complexity of chromogranin A as a plasma marker, where the protein is extensively and variably processed to a plethora of peptide fragments. Current immunological methods for clinical measurement differ dramatically with respect to both epitope choice and clinical validation.