Privileged witnesses: how interventional cardiologists can validate experimental evidence in practice

Immersed in our everyday activities and busy work schedules, we run the risk of failing to appreciate our privileged position as interventional cardiologists to witness and gain insights into many aspects of cardiac physiology. Fortunately, every now and then, we come across fresh observations that support or reinforce a body of knowledge largely obtained in the experimental laboratory. This is indeed the case for the research published on coronary flow regulation in this issue of EuroIntervention by Marin and colleagues1.

To trace the context of this research, we should go back to the French physiologist Claude Bernard, who, in 1865, coined the term “milieu intérieur” and the associated concept of homeostasis to describe the steady internal physical and chemical conditions that are autonomously maintained in living organisms. One specific case of homeostasis is regulating arterial blood supply under shifting conditions. In 1902, Bayliss found that hindlimb arterioles regulate flow through an intrinsic myogenic reflex that reacts to variations of intraluminal pressure, thus keeping flow constant before arterial pressure shifts2, and in 1959, Lassen demonstrated the existence of a cerebral...