Differential Diagnosis

The patient's presentation suggests a condition affecting cardiac function, particularly with elevated filling pressures and significantly elevated right atrial pressure. Here's a categorized differential diagnosis:

• Single most likely diagnosis
  • Constrictive Pericarditis: This condition is characterized by a thickened, fibrotic pericardium that restricts diastolic filling of the heart, leading to elevated filling pressures. The normal left ventricular size, thickness, systolic function, and wall motion, along with significantly elevated right atrial pressure without pulmonary hypertension, support this diagnosis.
• Other Likely diagnoses
  • Restrictive Cardiomyopathy: This condition involves stiffening of the heart muscle, making it difficult for the ventricles to fill with blood. It can present similarly to constrictive pericarditis, with elevated filling pressures and normal systolic function.
  • Cardiac Amyloidosis: A condition where abnormal proteins (amyloid) accumulate in the heart, leading to restrictive cardiomyopathy. It can cause elevated filling pressures, normal systolic function, and significantly elevated right atrial pressure.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Tamponade: Although the question does not provide direct evidence of tamponade (e.g., diastolic collapse of the right ventricle), significantly elevated right atrial pressure without an obvious cause warrants consideration of this life-threatening condition.
  • Right Ventricular Infarction: This condition can cause elevated right atrial pressure due to right ventricular dysfunction. Although the question states normal right ventricular systolic function, the possibility of a recent or evolving infarction should not be entirely dismissed without further evaluation.
• Rare diagnoses
  • Glycogen Storage Disease: A rare genetic disorder that can lead to restrictive cardiomyopathy, presenting with elevated filling pressures and normal systolic function.
  • Fabry Disease: A genetic disorder that can cause restrictive cardiomyopathy due to the accumulation of a particular type of fat in the heart, leading to elevated filling pressures and normal systolic function.
  • Sarcoidosis: A condition where inflammatory cells (granulomas) accumulate in various organs, including the heart, potentially leading to restrictive cardiomyopathy and elevated filling pressures.