Prognostic Value of Plasma Lactate Levels Among Patients With Acute Pulmonary Embolism: The Thrombo-Embolism Lactate Outcome Study

Study objective We investigate the prognostic value of plasma lactate levels in patients with acute pulmonary embolism. Methods We studied adult patients with symptomatic, objectively confirmed pulmonary embolism presenting to a single emergency department. Plasma lactate and troponin I levels were tested at presentation. We considered lactate values greater than or equal to 2 mmol/L and troponin I values greater than or equal to 0.10 ng/mL to be abnormal. Right-sided ventricular dysfunction was assessed by echocardiography. Primary endpoint was all-cause death occurring on or before 30 days after presentation. Secondary endpoints were the composite of all-cause death and clinical deterioration (defined as progression to shock, mechanical ventilation, or cardiopulmonary resuscitation) and death caused by pulmonary embolism. We tested the association between lactate level greater than or equal to 2 mmol/L and the endpoints using Cox proportional hazards regression analysis. Results Of the 270 patients included in the study, the mean age was 73 years (SD 12.7 years) and 151 (55.9%) were women. Twelve patients (4.4%) showed shock or hypotension (shock or systolic arterial pressure