Article: Emergency physician performed tricuspid annular plane systolic excursion in the evaluation of suspected pulmonary embolism
Daley J, Grotberg J, Pare J, et al. Emergency physician performed tricuspid annular plane systolic excursion in the evaluation of suspected pulmonary embolism. Am J Emerg Med. 2017;35(1):106-111. doi:10.1016/j.ajem.2016.10.018
Objective:
When considering the diagnosis of pulmonary embolism (PE), it can help to assess right ventricular dysfunction (RVD), which occurs in 30-70% of patients with PE. Tricuspid annular plane systolic excursion (TAPSE) assesses for RVD. TAPSE measures the dynamic movement of the tricuspid valve annulus over the course of a contraction.
This study aimed to describe the characteristics of TAPSE that can diagnose PE, such as the optimal measurement cutoff.
Secondary objectives were to assess the interrater reliability when measuring TAPSE, to determine the ability to visually estimate TAPSE qualitatively as normal or abnormal before its measurement, and to describe the diagnostic characteristics of other measures of right heart strain assessed on FOCUS for PE.
Design: This study is a prospective observational cohort study involving a convenience sample of patients undergoing focused right heart echo before CTA for suspected CT. It was conducted at a large, urban academic medical center from April 2015 to April 2016.
Patient selection:
Inclusion Criteria: Patients 18 years of age and older with the ability to consent who presented to the ED and where undergoing CTA for possible PE.
Exclusion Criteria: Prisoners, Wards of the state, non-English speakers
Methods: Investigators performed and interpreted the FOCUS exam at the patient’s bedside during their stay in the ED. If possible, the FOCUS exam was performed prior to the patient receiving the CTA. Echocardiographers were blinded to the results of the CTA and those interpreting CTA were blinded to the FOCUS results.
Investigators underwent a training session, which included a didactic portion and a required number of practiced TAPSE measurements prior to enrolling patients in the study.
FOCUS is a right heart echo that includes TAPSE and other signs of RVD including: right ventricular enlargement, septal flattening, tricuspid regurgitation, or McConnell’s sign (akinesia of the mid-free right ventricular wall with preserved apical contractility). A TAPSE measurement of <1.7 cm was considered indicative of RVD, as determined by prior literature.
TAPSE is measured in the apical 4-chamber view, with the M-mode cursor placed over the lateral tricuspid valve annulus. This creates a wave form which can then be measured from peak to trough.
Results:
Using a threshold of 1.7 cm, TAPSE was 56% (95% CI, 38-74) sensitive and 79% (95% CI, 78-86) specific for PE. A threshold of 2.0 cm yielded a sensitivity of 72% (95% CI, 53-86) and specificity of 66% (95% CI, 57-75). In a post hoc analysis of hemodynamically unstable patients, TAPSE was 94% (95% CI, 71-99) sensitive.
interrater reliability of TAPSE was compared between 2 emergency providers, and found to have an interclass correlation coefficient of 0.87.
In 68 patients, providers visually estimated TAPSE as abnormal (<1.7 cm) with a K statistic of 0.94 (13 of the 68 had an abnormal TAPSE)
Takeaway:
The historically used cutoff for a normal TAPSE is 1.7 cm, however this was not developed for the diagnosis of PE. This study found that a cutoff of 2.0 cm may be more appropriate for the diagnosis of PE in the ED, as using a higher cutoff value improves sensitivity of TAPSE for PE. TAPSE is a highly reproducible and reliable measure. The sensitivities of TAPSE and other measures of RVD for PE were moderate at best, limiting the diagnostic utility in all patients presenting with concern for PE. However, it is still of clinical utility in patients presenting with hemodynamic instability, as it appears to be highly sensitive for PE in patients with tachycardia or hypotension.
Authors: Hannah Thomas, MS4 and Kaitlin Reznick-Lipina, MS4