What ECG Findings Predict Crashing in Acute PE?

Written by Graham Van Schaik

Spoon Feed
In patients with acute pulmonary embolism (PE), only supraventricular tachycardia (SVT) was an independent predictor of clinical deterioration (CD); however, other ECG findings (below) were associated with abnormal RV function (abnl-RV) on echo.

Why does this matter?
As emergency physicians, PE should always be on our differential for chest pain, shortness of breath, syncope, etc. Once we’ve found a PE, it is helpful to have a sense of who might need a higher level of care to prevent CD, particularly as these patients remain boarded in our departments. Having parameters by which we can risk-stratify patients gives us a sense of who needs a little more attention.

Take my breath away…
This was a prospective, multicenter study of 1,736 newly confirmed PE patients. Of the 1,629 patients with both ECG and echo, ~25% experienced CD, defined as respiratory failure, hypotension, dysrhythmia, cardiac arrest, escalated PE intervention, or death within 5 days. Of the same 1,629 patients, ~32% had abnl-RV, which had an OR for CD of 4.25 (3.35, 5.38). On the other hand, absence of abnormal ECG findings had an OR for CD of 0.34 and abnl-RV 0.24, both statistically significant.

Only one ECG pattern had a significant OR of 2.87 for CD – SVT. T-wave inversions in V_2-4, incomplete right bundle branch block, ST elevation in aVR, sinus tachycardia, and S1-Q3-T3 were all independent predictors of abnl-RV on echocardiogram.

Source
Electrocardiographic findings associated with early clinical deterioration in acute pulmonary embolism. Acad Emerg Med. 2022 Jun 24. doi: 10.1111/acem.14554. Online ahead of print.