Clinical relevance of ventriculo-arterial coupling and how to assess it at the bedside

This review describes ventriculo-arterial coupling (VAC), its clinical relevance and how to access it at the bedside. VAC refers to the interaction between the contractility of the ejecting ventricles and the load exerted by the arteries. It integrates cardiac performance with the properties of the vascular system to assess cardiovascular efficiency and workload ending in a stroke volume and energy required to create that work. This relationship is quantitatively expressed as the ratio between arterial elastance (Ea) and end-systolic ventricular elastance (Ees). VAC offers valuable insights into hemodynamic status that go beyond traditional parameters like blood pressure, stroke volume or ejection fraction and independently predicts outcome from critical illness. Optimal VAC reflects maximal efficiency of stroke work and preserved cardiovascular reserve, while uncoupling indicates impaired reserve and is associated with worse prognosis. Uncoupling can occur in both acute and chronic settings, can affect either the right ventricle and pulmonary circulation or left ventricle and systemic circulation or both, and is observed across most forms of shock. While VAC has traditionally been analyzed through invasive pressure-volume methods, it can now be approximated at the bedside using echocardiography and simplified elastance calculations. These approaches allow for dynamic assessments of therapeutic interventions, including fluids, vasopressors, inotropes, and mechanical circulatory support. By incorporating VAC into clinical practice, healthcare professionals can enhance hemodynamic phenotyping and support individualized, physiology-guided management of critically ill patients.