Intravenous Albunex during transesophageal echocardiography: quantitative assessment by videodensitometry and integrated backscatter analysis from unprocessed radiofrequency signals.

This study investigates the comparative sensitivity of video and radiofrequency imaging to detect changes of the myocardial acoustic properties after intravenous Albunex. Thirty-six patients received Albunex, 0.08 and 0.22 ml/kg intravenously, during transesophageal imaging of the ventricular short axis. Analysis of video images was performed in all patients and of radiofrequency data in 20 patients. Although myocardial videointensity remained unchanged, 57% of the myocardial backscatter plots demonstrated significant contrast enhancement. The study demonstrates that intravenous Albunex is capable of myocardial contrast enhancement and proves the diagnostic superiority of radiofrequency compared with video imaging. Ultrasonic radiofrequency imaging may provide a technical basis for future noninvasive assessment of myocardial perfusion.