Pericardiocentesis for cardiac tamponade was followed within 24 hours by the development of a new 1.5 × 1.2 cm right ventricular thrombus and acute bilateral pulmonary emboli in a 54-year-old man.
Case Report (n=1)
Relief of cardiac tamponade via pericardiocentesis can restore venous return and mobilize pre-existing thrombi, leading to acute right ventricular thrombus and pulmonary embolism.
Abstract Introduction Pericardiocentesis reverses the hemodynamic constraint of cardiac tamponade and typically improves perfusion. Thromboembolic events immediately after drainage are underrecognized. We report a unique case of a patient in whom a new, mobile right ventricular (RV) thrombus and acute bilateral pulmonary emboli (PE) were identified within 24 hours of pericardiocentesis. It highlights a plausible flow-mediated mechanism for thrombus mobilization after relief of intrapericardial pressure. Case Presentation A 54-year-old man with type 2 diabetes, hyperlipidemia, papillary thyroid carcinoma status post-total thyroidectomy and neck radiation four years prior, and ensuing hypothyroidism, presented with progressive dyspnea and orthopnea. Transthoracic echocardiography showed a large circumferential pericardial effusion with tamponade physiology. Urgent pericardiocentesis drained 1.3 liters of sanguineous fluid, which was revealed to be lymphocyte-predominant (62% lymphocytes). Cytology and cultures, including mycobacterial studies, were negative. No evidence of malignancy recurrence, autoimmune, or infectious etiology was found during the evaluation. A repeat echocardiography at 24 hours demonstrated a new, freely mobile RV thrombus measuring 1.5 × 1.2 cm, moderate RV dysfunction, and McConnell’s sign. Computed Tomography pulmonary angiography revealed new bilateral segmental PEs. The patient remained hemodynamically stable, was started on therapeutic unfractionated heparin infusion, and was transitioned to apixaban at discharge. Discussion Before drainage, elevated intrapericardial pressure restricts right-sided filling and reduces venous return; systemic venous pressures rise, and stasis may favor thrombus formation in peripheral veins or the right atrium/inferior vena cava. Abrupt decompression restores venous return and RV inflow, providing forward flow that can mobilize a pre-existing thrombus into the RV and pulmonary arteries—consistent with the timing and imaging in this case. Post-pericardiocentesis RV thrombus with PE appears rare but clinically significant. Routine prophylactic anticoagulation solely for drainage is not supported; however, early post-procedure vigilance is warranted, including symptom checks (pleuritic pain, dyspnea, syncope), pulse-oximetry trends, and a low threshold for repeat echocardiography or CT angiography when RV dysfunction or a mobile intracardiac mass is suspected. When confirmed and hemodynamics permit, therapeutic anticoagulation is appropriate; thrombolysis or embolectomy may be considered for instability. Conclusion Relief of tamponade can unmask or mobilize thrombus, leading to RV thrombus and PE shortly after pericardial drainage. Focused post-procedure monitoring may enable timely detection and treatment. Early recognition may prevent catastrophic outcomes through prompt anticoagulation or intervention. This abstract is funded by: None
Kasmani et al. (Fri,) conducted a case report in Cardiac tamponade (n=1). Pericardiocentesis was evaluated on Right ventricular thrombus and pulmonary emboli. Pericardiocentesis for cardiac tamponade was followed within 24 hours by the development of a new 1.5 × 1.2 cm right ventricular thrombus and acute bilateral pulmonary emboli in a 54-year-old man.