Superiority of second harmonic imaging for echocardiographic measurement of left ventricular volumes: Comparison with angiocardiography.

Analysis of left ventricular volumes is a prognostic factor in cardiovascul ar disease. Echocardiography is a means of obtaining these parameters but i s limited by poor reproducibility. Recently, a new echocardiographic techni que, second harmonic imaging (SHI), developed through contrast agent method s, significantly improved the quality of Imaging. The aim of this study was to demonstrate the value of SHI for assessing left ventricular volumes. Thirty patients admitted for cardiovascular evaluation and requiring angioc ardiography underwent echocardiography with calculation of end diastolic (E DV) and end systolic volumes (ESV) of the left ventricle in fundamental (FI ) and second harmonic (SHI) imaging. These measurements were compared with those of angiocardiography. The reproducibility of SHI was calculated after repetition of the measurements by two independent observers for both echoc ardiographic modes. There was a significant improvement of the parameters of linear regression in SHI compared with Fl both for EDV (r= 0.93 versus 0.76) and for ESV (r= 0.94 versus 0.83). the reproducibility was also significantly improved in S HI (relative error of 5% versus 12% for intra-observer error and 6% versus 13% for inter-observer error). The authors conclude that SHI significantly improves two-dimensional imagin g and provides a reliable and reproducible measurement of left ventricular volumes.