False-positive stress echocardiograms: Predictors and prognostic relevance

Background: Recent studies indicate that the pretest likelihood of significant coronary artery disease (CAD) (≥50% luminal stenosis) is over-estimated and that the frequency and severity of positive stress tests have been decreasing. This suggests an increased prevalence of false-positive (FP) stress tests. The aims of this retrospective study were to investigate the predictors of FP stress echocardiography (SE) and to compare the outcomes of patients with FP results to those with true-positive (TP) results.

Methods: Patients who underwent SE between 2013 and 2017 in a tertiary-care center were reviewed. Included were patients aged ≥40years who had cardiac catheterization (CC) within 1year of the index stress test. SE was considered FP if a new or worsening wall motion abnormality was present in the absence of significant corresponding CAD.

Results: Of the 5100 patients with SE, 1069 satisfied inclusion criteria. A total of 305 patients had positive SE results; of which 162 (53%) were FP. Logistic regression revealed that female gender (p=0.009), the absence of diabetes (p=0.03), the absence of a personal history of CAD (p=0.004), and lower stress WMSI (p=0.03) were independently associated with FP results. Patients with FP results on SE had similar all-cause mortality to those with TP results.

Conclusions: Accounting for predictors of FP findings on SE could improve the interpretation of SE results and limit the use of unnecessary CC. Furthermore, patients with FP results on SE could benefit from aggressive risk factor control and careful clinical follow-up.