Shared decision making (SDM) is a process whereby patients and clinicians work together to make informed medical decisions that incorporate patient values. Recent data suggest that, for patients with low pretest probability of pulmonary embolism (PE), doubling the standard d-dimer cutoff may reduce the need for imaging with minimal increase in missed PE diagnoses. We used an SDM approach to determine patient preferences regarding this diagnostic approach.

We prospectively enrolled a consecutive sample of emergency department (ED) patients presenting with chest pain or dyspnea. We provided patients with a standardized description of the diagnostic workup for PE. We also provided image arrays describing the risks of computed tomography in low pretest probability patients and the risks of deferring imaging assuming a d-dimer was less than twice the value normally considered positive. We surveyed patients for their preference to undergo or defer imaging in this scenario.

We enrolled 203 ED patients. Mean age was 55 ± 17 years, and 61% were male. Seventy-four patients (37%) elected to defer computed tomography of the pulmonary arteries testing. Patients with a previous PE diagnosis were less likely to defer computed tomography of the pulmonary arteries testing (P = .007). There was no association between the decision to defer testing and age, sex, family history of PE, or self-assessed risk-taking tendency.

When presented with a hypothetical scenario, more than one-third of patients deferred imaging for PE based on low clinical probability and a d-dimer less than twice the normal threshold. An SDM approach is acceptable to patients and may decrease imaging for PE.