Abstracts $31 172 Pulse inversion technology - a new contrast specific imaging modality for myocardial perfusion imaging K. Tiemann, H. Becher, T. Schlosser, S. Kuntz, H. Omran, M. Bangard I, A. Ehlgen, C. Veltmann, J. Goenechea, B. LOderitz Dept. of Cardiology, University of Bonn, Bonn, Germany INuclear Medicine, University of Bonn, Bonn, Germany Pulse Inversion Technology (PI) is a new contrast specific imaging modality. In PI two short consecutive pulses which are phase- shifted exactly about 180± are emitted to generate one image frame. The echo of the two reflected pulses are added to generate an image frame. In non moving tissue which contains no contrast signal both pulses result in a zero amplitude if added together. Non-linear signals from tissue or bubbles result in strong PI- signals. By its nature PI rejects the fundamental component of the signal without need of filter procedures. In 15 volunteers and 20 patients contrast effects in the LV-cavity (CC) and the myocardium (MC) of PI were compared to Contrast Harmonic Imaging. Levovist~ (400mg/ml) was infused at a constant infusion speed (4mVmin). Triggered imaging (every 5th cardiac cycle) was per- formed using both modalities. Off-line analysis of digitally stored raw data was performed using a calibrated software tool. Following background subtraction signal intensities in the standard segments were calculated. Results: Mean CC for HI was 24 ± 5 dB and for PI 31±7 dB.MC for basal septum 7.9+2.2 (HI)t0.3±3, mid septum 12.3±4.1 (Hi) and 17.4±4.9 (PI), apical septum 9.8±3.6 (HI) and 13.9_4.2 (PI), basal lateral 2.5+_0.2 (HI) and 3.9+1.2 (Pl), mid lateral 8.6±1.9 and 12.1 _+5.4 (PI) finally apical lateral 7.3±2.7 and 10.0±3.2 (PI). Average contrast enhancement was significantly higher for PI (p<O.001). Conclusions: CC using PI is feasible. PI significantIy improves the detection of myocardial contrast signals. 174 Myocardial perfuslon by Intravenous echo contrast and by nuclear imaging MA. Morales, D. Reval, A. Gimelfi, C. Marini, U. Startari, A. Sestili, P. Marzullo, A. L' Abbate CNR Institute of Clinical Physiology, Pisa, Italy The combination of harmonic intermittent imaging, Power Doppler and intravenous echo contrast administration provides information regarding myocardial perfusion. The aim of this study was to examine the capability of this method to detect perfusion defects in patients (pts) with abnormal myocardial scintigraphy. Study population consisted of 32 pts (25 males, age 39-84 years), with previous Q (17 pts) or non-Q (11 pts) myocardial infarction, showing perfusion defects at rest 201 Thallium SPECT. Myocardial contrast enhancement (MCE) was achieved by intravenous admin- istration of a galactose-based contrast agent (Levovist, Germany). Contrast echo images (in the apical 4-chamber view) and nuclear scans (in the corresponding horizontal long-axis view) were di- vided into 6 segments according to a 16-segment model; myocar- dial perfusion was scored as 1 (normal), 0.5 (patchy or inhomogeneous perfusion) or 0 (no detectable perfusion). Interpretable contrast echo images were obtained in 184 seg- ments. Out of 34 segments with a Thallium score of zero, 23 showed an MCE score of zero, 6 a score of 0.5 and only 5 a score of 1. Out of 62 segments with a nuclear score of 0.5, 32 also showed an MCE score of 0,5 and 8 a score of O. Of the 88 segments with a Thallium score of one, 77 showed an MCE score of 1 and no one segment a score of 0. Out of 96 segments with abnormal Thallium uptake, 69 showed abnormal contrast en- hancement; out of 88 segments with normal Thallium uptake, 77 showed normal contrast enhancement (Kappa 0.589). The corre- lation coefficient between perfusion scores was 0.67. Thus, myocardial perfusion defects can be non invasively as- sessed by intravenous echo contrast during harmonic intermittent Power Doppler. 173 Interobserver variability of quantitative myocardial contrast-echocardiography (QMCE) studies in second harmonic B-mode (SHI) and power (Doppler) angio imaging (PAl) during dipyridamole- stressechocardiography (DSE) J. Wunderl[ch ~, G. Brand ~, IV. Pogacic ~, H. Polz 2, K. Wegscheider 3 ~lnstitute for Echocardiology and Stress.Echocardiography, Berlin, 2Fa. EchoTech, Munich, ~Department of Econometry and Biostatistics, University of Hamburg, Germany Introduction: Despite the fact that myocardial contrast echocardiography (MCE) can't be applied to detect coronary artery disease (CAD) into a routine clinical setting, numerous studies are underway which use MCE as a "routine test". But which is the preferred phase (systole vs. diastole), the frequency of gating cardiac cycles (one, two, four ...), the variability between the different ultrasound machines, the optimal dose of contrast agent, which criteda have to be measured etc.? The purpose of this study was to determine the interobserver-vadabiIity of two modes of imaging: SH1 and PAl during DSE. Methods: 1. Since November 1998 until June 1999 in 213 consecutive patients DSE was performed with QMCE in addition. 2. An HP Soaos 5500 and an Image Vue for the cine loop analysis were used. Imaging was done in second harmonic mode (1.8/3.6 MHz). DSE was performed in a standardised protocol with atropine in addition. A 16-segment model was used for the wall motion analysis. Scoring was done for 1 =normal; 2=hypokinetic; 3=akinetic, 4=dyskinetic. 3. The contrast studies were performed by bolus-injection of 0.3 ml Optison ® at rest and peak stress. 108 consecutive patients were randomly allocated either to SHI or PAl. By use of a trigger 1:1 at the beginning of the P-wave, and a mechanical index of 0.8 and approximately 2 minutes after injection of the contrast agent (at rest and peak) cardiac cycles were digitalized by use of QuantiConR soflware in order to measure v~deointensity (Vl). 8 regions of interest (ROI's) were used for VI- measurement (4-CH). Pulmonary transit time (PTi-), time to peak (rP), halt' time decay (HTD) , and area under the curve (AUC) of each ROI were evaluated. 4. Two observers did the ROI-analysis independently. 5. For the compads0n of the two observers 4-field-tables with Cohen's Kappa were used. Continual charactedstics were tested by the use of correlation or bivariate regression analysis respectively. Results: 1.51 patients were allocated to 8HI, 57 patients to PAl. 2. Baseline charactedstics were identical. 3. Cohen's Kappa for the parameters P]-I', TP, HTD and AUC of 8 ROl's ranged from 0.6 to 0.8. Overall correlation coefficient between the two observers was 0.6 for SHI and 0.85 for PAl. Conclusions: Interobservervariability between two observers and for PAl was low. "lhe higher variability of SHI was due to the lower image quality. 175 The Effect Of Quantitative Perfuslon On Sensitivity And Specificity Of Dobutamine Contrast Echocardiography In Technically Difficult Patients Melda Do/an, Kamala Tamirisa, Sanjeev Purl, Jean Flanagan, Elena Havens, Latish Mckinney, Jeanette St. Vrain, Kathleen Habermehl, Mort Kern, Arthur J. Labovitz St. Louis University, St. Louis, MO, USA Optison, a recently approved echo contrast ©, improves endocar- dial visualization during Dobutamine Stress Echocardiography (DSE); whether this improvement leads to improvement in sensi- tivity and specificity of DSE is not well known. Therefore we studied a total of 64 patients with technically difficult studies that underwent intravenous contrast administration during DSE. All patients (pts) underwent coronary angiography and nuclear imag- ing. Color coded perfusion analysis, regional wall thickening (WT) and percentage of endocardial border visualization (EBV) were performed oft-line. Overall characteristics of the study group: 40% of patients had 3 vessel disease, 45% had history of myocardial infarction, 56% had LAD lesion, and 61% had resting wall motion abnormalities. During DSE, EBV improved from 52±8% to 87±7% after contrast injection. SENSITIVITY SPECIFICITY DSE/Qualitative 73 80 DSE/W-I & Perfusion 88* 86 Nuclear 90* 85 P* 0.0t NS Sensitivity of DSE for detecting coronary artery disease _>70% was significantly perfusion and wall thickening analysis (73% versus 88%, p=0.0t), however still similar to sensitivities obtained with nuclear imaging (88% versus 90%, p=NS). Likewise, specificity was improved with contrast administration during DSE (80% versus 86%). Optison administration during DSE combined with perfusion analy- sis in technically difficult studies leads to improved sensitivity and specificity similar to that obtained with nuclear imaging. Eur J Echocardiography Abstracts Supplcment, December 1999