The recent study by Scolari et al. [1] entitled ‘Association between serum lactate levels and mortality in patients with cardiogenic shock receiving mechanical circulatory support: a multicenter retrospective cohort study’, published in the BMC Cardiovascular Disorders evaluates the prognostic role of serum lactate and lactate clearance over time in cardiogenic shock patients treated with mechanical circulatory support. The authors concluded that serum lactate levels are an important prognostic biomarker for 30-day mortality in cardiogenic shock patients treated with temporary mechanical circulatory support, i.e., the Impella CP device or venoarterial extracorporeal membrane oxygenation (ECMO). However, this study did not consider the impact of the two different types of mechanical circulatory support on the lactate kinetics in these critically ill patients. Consequently, the contextual interpretation of the findings in a complex and dynamic concept of lactate clearance during cardiogenic shock remains unclear.