Pericardiocentesis is an invasive procedure involving puncture of the pericardial space in order to aspirate fluid accumulated within this cavity. Removal of this fluid is indicated to relieve the pressure it exerts on the heart, since fluid contained within the pericardial cavity limits cardiac contractility and, consequently, impairs blood ejection, reducing cardiac output to the tissues and potentially leading to a life-threatening situation [1].In addition to its therapeutic purpose, pericardiocentesis may also be used for diagnostic purposes, allowing analysis of the aspirated fluid and enabling identification of potential traumatic, infectious, or neoplastic etiologies. In such cases, the intervention may even be performed electively, as in chronic pericardial effusions of unclear cause.Over the evolution of pericardiocentesis techniques, it has been established that the safest and most successful management is associated with the use of ultrasonography as procedural guidance. Therefore, the procedure should preferably be performed under ultrasound guidance, allowing visualization not only of the pericardial space and its surroundings, but also of the instruments used for puncture and the depth of needle penetration [2].Thus, to perform pericardiocentesis accurately, the clinician must have a solid understanding of regional anatomy, procedural technique, and ultrasonographic interpretation.