Evaluation of left ventricular functions using a cadmium telluride probe

We developed a new single cardiac probe system made by cadmium telluride (CdTe). The advantage of this system is in the small and light equipment and its easy attachment to the chest wall. With this system, left ventricular functions can be evaluated by the following two modes; beat-to-beat (SB) mode and ECG multigated (MB) mode, using an equilibrium radionuclide red blood cell label. The purposes of this study are to evaluate the feasibility of newly developed CdTe probe system 1) comparing the left ventricular functions obtained from the CdTe probe and those from the gamma camera (G), and 2) monitoring LVEF continuously. In 33 patients (pts) with various heart diseases, the left ventricular functions were estimated with CdTe, NaI and G. Significantly close correlations were elicited between the LVEFs obtained by CdTe and G; the correlation coefficients (r) were 0.935 in SB mode and 0.892 in MB mode respectively (both p < 0.01); the correlation coefficients between LVEFs obtained by CdTe and NaI were 0.939 in SB mode and 0.896 in MB mode (both p < 0.01). Samely, 1/3 EF had a good correlation (r = 0.716, p < 0.01), PER and PFR had significant correlations (r = 0.682 and 0.777; both p < 0.01). The inter-record reproducibility of LVEFs obtained by CdTe were reasonably good (r = 0.949 in SB mode, r = 0.895 in MB mode; both p < 0.01). The continuous monitoring of LVEF was tested using a newly designed vest system for 30 minutes, which was enable to detect the effect of ISDN on LVEF. We conclude, therefore, that the CdTe probe system was proved to be useful for the evaluation of LVEF not only in ambulatory patients but also in acutely ill patients in intensive and coronary care units. (author)