52F with known lung adenocarcinoma presents with progressive dyspnea and hypotension (BP 88/60). Echo shows large circumferential effusion with RV collapse. Pulsus paradoxus is 18 mmHg. JVP elevated, heart sounds muffled. Is this classic Beck's triad tamponade? When is pericardiocentesis truly emergent vs semi-elective? Is surgical pericardial window better in malignant effusions?
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