Both constrictive pericarditis and restrictive cardiomyopathy limit ventricular filling, but for completely different reasons. They share nearly identical symptoms and often similar Doppler findings such as dyspnea, edema, JVD, preserved EF and abnormal filling, which is why they’re so commonly mistaken for one another. But they arise from completely different mechanics, one from the outside of the heart, one from the inside.

Learn how to diagnose cardiac tamponade using echocardiographic signs, Doppler clues, and hemodynamic changes. Identify critical pressure patterns before clinical shock develops.

While we often think of the pericardium as a protective sac, it’s so much more than that. Under normal conditions, it moves and stretches with every heartbeat, quietly accommodating changes in volume and pressure.  But when it loses that flexibility, the pericardium can transmit pressure back to the heart or even restrict its ability to fill.  And that’s where the pericardial spectrum begins. A continuum that ranges from simple effusion to hemodynamic tamponade and, in chronic or recurrent inflammation, to constriction. Understanding this progression changes the way we view the pericardium and how we interpret our echo findings.

The concept of RV–PA coupling and uncoupling can sound intimidating, but it’s really about how well the right ventricle (RV) and the pulmonary arteries “work together”. Coupling is the measure of teamwork between the right ventricle and the pulmonary circulation—how efficiently the RV converts its contraction into blood flow through the lungs.