Cardiorenal Syndrome Type 1 Complicated by Uremic Pericarditis and a Small Pericardial Effusion Causing Cardiac Tamponade.

Cardiac tamponade is typically associated with large pericardial effusions; however, even small effusions can result in significant hemodynamic compromise, particularly in the setting of rapid fluid accumulation and underlying cardiac pathology. This case highlights the diagnostic challenge of identifying low-volume tamponade in a patient with elevated baseline intracardiac pressures. An elderly man was admitted for acute heart failure complicated by cardiorenal syndrome. Following initial diuresis, he developed paradoxically worsening hypotension and pleuritic pain. The absence of a pericardiocentesis, along with clinical recovery, suggested that the patient experienced a spectrum of pericardial constraint rather than definitive, high-pressure tamponade. Severe uremia and a small pericardial effusion suggested uremic pericarditis. Swan-Ganz catheterization showed elevated and relatively concordant diastolic pressures. While diuresis initially complicated the clinical picture, anti-inflammatory therapy with prednisone and colchicine resulted in clinical improvement. This report serves to define the importance of multimodal hemodynamic assessment when classic echocardiographic signs of tamponade are masked by preexisting cardiac remodeling.