Systematic Quality Improvement in Dobutamine Stress Echocardiography: A Two-Cycle Audit Demonstrating Enhanced Diagnostic Accuracy.

backgroundDobutamine stress echocardiography (DSE) has become an important and frequently used non-invasive diagnostic tool for assessing significant coronary artery disease (CAD) in clinical practice. This technique offers several advantages over alternative diagnostic methods, including the absence of radiation exposure, relatively widespread availability across healthcare facilities, and cost-effectiveness compared to nuclear imaging or cardiac magnetic resonance imaging. However, the diagnostic accuracy of DSE depends heavily on multiple factors, including the quality of image acquisition, appropriate patient preparation, and the interpretative expertise of the performing physician. As an operator-dependent investigation, DSE requires continuous quality assessment to maintain diagnostic accuracy and ensure optimal patient outcomes. Without systematic monitoring, variations in technique, interpretation, and patient preparation can lead to suboptimal diagnostic performance, potentially resulting in false negative results that miss significant coronary disease or false positive findings that lead to unnecessary invasive procedures. Systematic audit provides a structured framework for identifying performance gaps, comparing results against established benchmarks, and implementing evidence-based improvements. Regular audit cycles enable clinicians to objectively evaluate their diagnostic accuracy against the reference standard of coronary angiography (CAG), identify specific areas requiring improvement, and implement targeted corrective measures. This approach ensures that patients and referring physicians can have confidence in the diagnostic reliability of the DSE test while promoting continuous professional development and maintaining high clinical standards.

objectivesTo evaluate DSE diagnostic accuracy against CAG and assess improvement following specific quality interventions. This two-cycle audit applied the Plan-Do-Study-Act (PDSA) framework and assessed diagnostic performance using sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy measured against CAG as the reference standard.

methodsTwo-cycle clinical audit conducted in a non-invasive cardiology practice. Cycle 1 (October 2021-September 2024) included 160 DSE procedures; 75 (46.9%) underwent CAG procedures. Following analysis and intervention implementation, Cycle 2 (February 2025-October 2025) included 27 DSE procedures with 18 (66.7%) subsequent CAG procedures. The primary outcome was concordance between DSE and CAG results. The sensitivity, specificity, PPV, NPV, and overall accuracy were calculated.

resultsOverall accuracy improved from 82.7% (62/75) in Cycle 1 to 88.9% (16/18) in Cycle 2, representing a 6.2 percentage point improvement. False positive results were eliminated entirely (4.0% to 0%), while false negatives decreased modestly (13.3% to 11.1%). Analysis revealed that both false negatives in Cycle 2 resulted from failure to withhold nitrate therapy, prompting implementation of a three-tier medication verification checklist.

conclusionsSystematic audit with targeted interventions successfully enhanced DSE diagnostic accuracy. The medication verification checklist addresses a preventable systematic error and represents a transferable safety strategy applicable to other stress testing modalities.