Pericardial constriction and restrictive cardiomyopathy are distinct conditions affecting cardiac function, often challenging to differentiate clinically. Pericardial constriction arises from a rigid, thickened pericardium that restricts diastolic filling, leading to equalization of diastolic pressures across all four chambers. This is commonly identified by specific ultrasound findings like septal bounce and respiratory variation in ventricular filling.
In contrast, restrictive cardiomyopathy is a myocardial disorder characterized by stiff ventricular walls that impair diastolic filling, despite a normal or near-normal pericardium. Ultrasound helps distinguish these by assessing myocardial stiffness and often showing normal or elevated myocardial velocities. Accurate differentiation via ultrasound is crucial for guiding appropriate medical and surgical management.