Energy, flow and pressure in the cardiovascular system: a narrative review of how the circulation works

The authors aim to clarify the mechanisms that determine blood flow in the cardiovascular system, challenging traditional pressure-based concepts that can lead to confusion and potentially harmful treatment in clinical settings. By integrating classical and contemporary physiological insights, they propose a unified framework where the heart provides energy, vascular properties dictate flow potential, and pressures merely reflect system states rather than driving forces. This approach emphasizes the importance of assessing flow responsiveness and cardiac reserve over static pressure targets in managing shock and other critical conditions.