A 74-year-old male with tachy-brady syndrome underwent a dual chamber pacemaker insertion. Three weeks after the procedure, the patient presented with dyspnea, melena and hypotension refractory to intravenous hydration and blood transfusion. An echocardiogram revealed a normal ejection fraction and a large pericardial effusion with impending tamponade that required emergent transportation to a tertiary care facility. An echocardiogram done at the tertiary care facility showed a large pericardial effusion with cardiac tamponade, thrombus overlying the right ventricle, which were consistent with right ventricular perforation induced by pacemaker insertion. The emergent pericardial window was created and 850 mL of blood was drained.