Live 3D echo guidance of catheter-based endomyocardial injection.

Local delivery of therapeutic agents into the myocardium is limited by suboptimal imaging. We evaluated the feasibility and accuracy of live 3D echo to guide left ventricular endomyocardial injection. An intramyocardial injection catheter was positioned in the left ventricle in five healthy Yorkshire pigs using fluoroscopy.

Integrated backscatter during harmonic and fundamental frequency imaging--effect of depth, mechanical index, and tissue anisotropy: implications for myocardial tissue characterization.

Objective: To explore the potential advantages of tissue harmonic imaging (THI) versus fundamental frequency imaging (FFI) when applied to tissue characterization.

Methods: A Philips Medical Systems Sonos 5500 echocardiograph equipped with a broadband transducer (S4) and an on-line quantitative analysis software package (Acoustic Densitometry) was used for imaging. The effect of mechanical index (MI), imaging depth, and anisotropy on relative backscatter amplitude was evaluated.