The universal definition of myocardial infarction has proved how important the role of biomarkers in the assessment of acute coronary syndrome (ACS) has become. As a result, management of patients with ACS today is more specific and personalized than ever, but there is still a lot of room for improvement. Unmet needs for a faster and more specific rule-in and rule-out of myocardial infarction, for a pronounced risk assessment allowing for standardized guidelines on personalized therapy and for an effective monitoring of our therapeutic efforts to guarantee an optimal risk-benefit turnout still require intensive biomarker research and clinical validation. This review addresses a set of cardiovascular biomarkers with different pathophysiological backgrounds and discusses their diagnostic, prognostic and therapeutic value in the setting of ACS and percutaneous coronary intervention (PCI). The article provides a review of the current knowledge and literature on biomarkers in ACS and PCI, discussing currently used biomarkers like cardiac troponin (cTN), high sensitive cardiac troponin (hscTn), natriuretic peptides (NPs) as well as promising future biomarkers like copeptin, choline and lipoprotein-associated phospholipase A2 (LP-PLA2). The review concentrates on the clinical application of these markers, evaluating not only their diagnostic and prognostic value but also their integrability into routine practice. There are currently a number of new biomarkers and new biomarker assays under investigation which give hope for a much improved diagnostic and risk stratification process. Large diagnostic clinical trials are still needed to evaluate their impact on ACS patient management and subsequent PCI in clinical practice.