Abstract

Background Real-time perfusion (RTP) echocardiographic imaging with a continuous infusion of microbubbles has improved the sensitivity of dobutamine stress echocardiography (DSE) in detecting coronary artery disease (CAD). The impact of RTP on treadmill exercise stress echocardiography (TESE) is unclear.

Design Retrospective database review.

Setting/patients/interventions RTP was utilised in 254 DSE and TESE patients being examined for the presence of significant CAD. A continuous infusion of 3% Definity (Lantheus Medical Imaging) was used for all studies, and contrast replenishment (MCR), plateau intensity (PMCE) and wall motion (WM) were examined for the detection of CAD.

Main outcome measures Sensitivity/specificity/accuracy to detect CAD.

Results For DSE, the sensitivity of myocardial perfusion (MP) imaging with RTP was 85%, which was significantly higher than WM analysis (72%; p<0.05). The improvement in sensitivity with MP analysis during DSE was primarily the result of better detection of left anterior descending disease. MP sensitivity during TESE was significantly better than MP sensitivity during DSE (98% versus 85%; p<0.05), and WM sensitivity during TESE was better than WM sensitivity during DSE (89% versus 72%; p<0.05). The improvement in WM sensitivity during TESE was due to detection of subendocardial wall thickening abnormalities in 48% of the patients with induced subendocardial perfusion defects.

Conclusion Myocardial perfusion imaging with RTP improves the detection of CAD during both DSE and TESE. During TESE, the subendocardial perfusion defects improve WM sensitivity by delineating subendocardial WM abnormalities.