Not Starling’s First Name: Acknowledging Otto Frank’s Legacy in Physiology Education

The Frank-Starling law is a cornerstone of cardiovascular physiology, yet its name often leads to amusing misconceptions. Many students assume "Frank" refers to Starling's first name, overlooking the physiologist whose quantitative approach transformed the study of the heart. This article revisits Frank's work within its historical and educational context. In his 1895 habilitation thesis, Zur Dynamik des Herzmuskels, Frank introduced mathematical analysis of ventricular pressure-volume relationships, establishing a framework that underlies modern pressure-volume loop interpretation. In 1899, in Die Grundform des arteriellen Pulses, he formalized the Windkessel model, representing the arterial system in terms of resistance and compliance and explaining how pulsatile ventricular ejection is converted into more continuous arterial flow. Beyond these theoretical contributions, Frank developed precision instruments, extended his work from frog heart preparations to mammalian physiology, and applied mechanical principles to cardiac function. His frameworks remain central to cardiovascular physiology and continue to support mechanism-based teaching through pressure-volume analysis and Windkessel modeling. Revisiting Frank's contributions highlights the enduring role of quantitative models in understanding and teaching physiological systems.