Diagnostic accuracy of dobutamine stress echocardiography in predicting significant coronary artery disease in the modern era

Background

Stress echocardiography (SE) is a widely used non-invasive tool for the evaluation of suspected coronary artery disease (CAD). Regional wall motion abnormalities (RWMA) during stress can localize ischemia to specific coronary territories. However, the diagnostic accuracy of SE may vary between the left anterior descending (LAD) and non-LAD (left circumflex and right coronary artery) territories. We aimed to evaluate the positive predictive value (PPV) of SE and the concordance between stress-induced wall motion abnormalities and angiographically confirmed coronary lesions, comparing LAD and non-LAD subgroups.

Methods

We enrolled 1793 patients with suspected ischemia. All patients underwent dobutamine SE and 246 patients had a positive test (defined as new or worsening RWMA during stress). Patients were subclassified into LAD (n=162) or non-LAD (n=90) groups based on the hypokinetic wall segments identified during SE. Six patients (3 males and 3 females) exhibited wall motion abnormalities in both LAD and non-LAD territories and were included in both subgroups for territory-specific analysis. All patients were referred for coronary angiography. A positive result was defined as the presence of significant coronary stenosis (≥70% stenosis). Lesion concordance was defined as a match between the hypokinetic territory on DSE and the culprit vessel on angiography.

Results

The study population comprised 246 patients (168 male [68.3%]; mean age 64.5 ± 10.5 years, range 40–86). Patients in the non-LAD group were significantly older than those in the LAD group (68.0 ± 10.4 vs 62.7 ± 10.1 years; p=0.025). Sex distribution was similar between groups (p=0.811). Overall, 199 of 246 patients (80.9%) had significant coronary disease confirmed on angiography, yielding a PPV of 80.9% (95% CI: 75.5–85.3%). Among patients with confirmed CAD, wall–vessel concordance was observed in 171 of 199 patients (85.9%; 95% CI: 80.4–90.1%). The PPV and concordance rates were comparable between LAD and non-LAD territories with no statistically significant differences (Coronary angiography positivity: 81.5% vs 81.1%, p=1.000; lesion concordance: 86.4% vs 86.3%, p=1.000).

In a subanalysis, we noted that 18 of the 30 false-positive LAD patients (60.0%) had stress-induced wall motion abnormalities isolated to the apex. After excluding these 18 apex-positive patients, the LAD PPV increased from 81.5% to 91.7% and the overall PPV increased from 80.9% to 87.3% . In this restricted analysis, the LAD PPV was significantly higher than the non-LAD PPV (91.7% vs 81.1%, p=0.024).

Conclusion

In this study of patients with positive stress echocardiography, SE demonstrated a high positive predictive value for identifying significant coronary artery disease and excellent wall–vessel concordance . These results reinforce the clinical utility of SE as a robust gatekeeper for coronary angiography, regardless of the suspected culprit territoryFlowcharttable