A 72-year-old male, with no pathological or family history, presents with dizziness, abdominal pain and non-dysenteric diarrheic depositions together with a syncopal episode lasting a few minutes, presenting a full recovery without neurological deficit.15 minutes later he enters emergency services alert, with no other symptoms, hydrated, with increased peristalsis.Parenteral hydration and initial paraclinical exams (ionogram, hemogram and electrocardiogram) are considered during his time at the emergency services, with no alterations evident.The electrocardiogram returned a sinus rhythm, no tachycardia, no signs of acute ischemia, no blockages.As the patient improved with hydration, the decision is made to release him.After this, the patient's upper extremities begin to move rigidly, and his eyes deviate to the left side.The patient then states he feels dizzy and weak overall, he looks pale and then presents persistent hypotension, extreme bradycardia, distal coldness and desaturation.Ultrasound tracing of the subxiphoid window was performed with ultrasound imaging within the ventricles.Thrombolysis is begun using a recombinant tissue plasmogen activator 100mg IV over 2hours.After this is started, the patient goes into pulseless electrical activity cardiac arrest.Cerebral pulmonary reanimation maneuvers are performed.Bicarbonate (7 direct ampoules) is used, and the dose of the recombinant tissue plasmogen activator thrombolytic agent changed to 50mg via bolus.After 35minutes of reanimation, the patient regains spontaneous circulation with a sinus rhythm and hemodynamic instability.Perfusion is begun with 10 mcg/min of Adrenaline and 20mcg/kg/min of Dobutamine.Assisted mechanical ventilation is continued without sedation and analgesia.He is transferred for an angiotomography of the pulmonary vessels where acute thrombi are identified in the main pulmonary arteries on both sides and in the segmental branches in the upper and lower lobes.