Contractility and Stroke Volume on Left Ventricular Pressure Volume Loop

In this video, we explore the concept of cardiac contractility and the End-Systolic Pressure-Volume Relationship (ESPVR). Contractility refers to the heart muscle's intrinsic ability to contract and is influenced by various factors including the autonomic nervous system, hormones, and drugs. The ESPVR is a crucial graphical representation that shows the relationship between end-systolic pressure (ESP) and end-systolic volume (ESV), with the slope of the ESPVR line (𝐸𝑒𝑠) indicating ventricular contractility. A steeper slope signifies increased contractility, leading to higher ESP, decreased ESV, and increased stroke volume (SV). Conversely, a flatter slope indicates decreased contractility, resulting in lower ESP, increased ESV, and decreased SV. Understanding these concepts is essential for diagnosing and managing cardiac conditions such as heart failure and optimizing therapeutic interventions.