DOBUTAMINE ECHOCARDIOGRAPHY - USEFULNESS OF DIGITAL IMAGE-PROCESSING

The present study was undertaken in order specifically to evaluate the usefulness of digital image processing so as to enhance the diagnosti c power of dobutamine stress echocardiography. For this purpose 44 dob utamine echocardiographic tests, routinely performed in our echo labor atory, were analysed blindly by two observers using traditional videot ape recording and digitized image acquisition. The results obtained fr om both observers show a trend which suggests that the traditional vid eotape approach provides more true-positive tests than the digitized a pproach (27/38 vs 23/38 and 24/38 vs 22/38 for the first and second ob server, respectively). True-negative test detection was 6/6 with the v ideotape and 5/6 with the digitized method for both observers. As a co nsequence of the discrepancies observed between the two modalities, th e videotape indicates that it can provide higher diagnostic accuracy t han the digitized approach (72 +/- 9% vs 63 +/- 10%). The tests result s concordance (positive or negative) between the two modalities of ana lysis was 66% for both the observers. The inter-observer agreement on the test results was 84% and 80% for the videotape analysis and the di gitized analysis, respectively. On the basis of the results, we consid er that digitized analysis applied to dobutamine stress echocardiograp hy does not afford significant diagnostic advantages and should not be considered as an alternative option to traditional videotape analysis . However, it may be considered an extremely useful integrative tool s ince it produces the on-line image evaluation more easily and faster a nd allows a more practical form of stress test storage.