- Evidence of severe PE: RV hypokinesis on echocardiography, abnormal troponin I or T (any non-normal including indeterminate values, using local reference thresholds) or BNP measurement >90 pg/mL or NT proBNP >900 pg/ml (not more than 6 hours prior to CT angiography and not more than 30 hours before enrollment) or a pulse oximetry reading <95% within previous two hours (<93% in Denver).