Case Presentation: An 87-year-old man with medical history significant for hypertension, non-ischemic cardiomyopathy, paroxysmal atrial fibrillation (anticoagulated on Rivaroxaban) and ventricular tachycardia (recently started on Amiodarone) presented to the emergency room with chest pain. He reported that the pain started insidiously 2 days prior to presentation, pleuritic, sharp, retrosternal and intermittent, associated with diaphoresis and nausea. No preceding trauma or history of viral prodrome. On examination, he appeared to be in acute distress; Physical examination revealed distant heart sounds and jugular venous distention. Vital signs revealed tachycardia (HR 101/min) and hypotension (BP 90/55 mm Hg). Electrocardiogram revealed low voltage complexes with sinus tachycardia. Laboratory tests showed evidence of hypo-perfusion – elevated creatinine (Cr 1.5, from normal baseline), lactic acidosis (lactate 2.2) and mildly elevated troponin (TnI 0.09). Chest X-ray revealed widened mediastinum. He was initially diagnosed with cardiogenic shock secondary to cardiac tamponade. Stat echocardiogram revealed pericardial effusion with evidence of tamponade. He subsequently had emergent pericardiocentesis (which revealed hemopericardium) and placement of pericardial drain. His symptoms gradually resolved, the pericardial drain was removed 2 days after placement, Amiodarone and Rivaroxaban were discontinued and he was discharged home in stable condition.
Discussion: We posited that our patient had spontaneous hemopericardium resulting from concomitant use of Rivaroxaban and Amiodarone. Rivaroxaban is a direct oral anticoagulant (DOAC) approved as an important alternative to warfarin in patients with nonvalvular atrial fibrillation. Both medications are substrates for the CYP3A4 hepatic pathway and concomitant use can result in increased plasma Rivaroxaban levels causing an increased propensity to bleeding.
Conclusions: While most physicians are cognizant of the need for renal dosing of Rivaroxaban, this abstract aims to increase awareness of its interactions with drugs that are also metabolized through the same hepatic CYP450 pathway and the possibility of life threatening complications if these agents are combined with Rivaroxaban.