Major pulmonary embolism, part 2: Diagnostic confirmation: Your choice of confirmatory study can help save a life

When historical information, physical findings, and basic laboratory data suggest major pulmonary embolism (PE), an expeditious approach to confirmation is mandatory. Transthoracic echocardiography (TTE) is ideal because it recognizes the cardiovascular characteristics of major PE and defines alternative diagnoses. The absence of right ventricular (RV) dilation on TTE effectively excludes major PE as the cause of the shock state. In patients who have TTE-defined RV dilation, immediate transesophageal echocardiography may help visualize the embolus and define the diagnosis at bedside. Spiral CT scans are replacing angiograms as the confirmatory studies of choice. They are noninvasive and readily available, and demonstrate excellent specificity, sensitivity, and predictive value.