transmural pressure
The pressure gradient across the wall of a blood vessel or cardiac chamber, calculated as the difference between internal and external pressures.
Full Definition
Transmural pressure represents the net distending force acting on vascular or cardiac walls and is fundamental to understanding cardiovascular mechanics. It equals the intraluminal pressure minus the extramural pressure and determines vessel diameter and wall stress. In cardiovascular anesthesiology, transmural pressure concepts are crucial for understanding ventricular function, especially during mechanical ventilation where pleural pressure changes affect cardiac filling. Positive pressure ventilation can reduce venous return by decreasing transmural pressure gradients.
Usage
Usage note: Often confused with intramural pressure; ensure correct usage in cardiovascular contexts.
In Context
- "Positive end-expiratory pressure reduced transmural pressure and venous return." — Hemodynamic analysis report
- "Transmural pressure calculations helped explain the patient's decreased cardiac output." — Physiological assessment documentation