Real-time three-dimensional echocardiography versus two-dimensional echocardiography in the diagnosis of left ventricular apical thrombi: preliminary findings

PURPOSE: Real-time 3-dimensional transthoracic echocardiography (RT-3D-TE) with real-time volume rendering (RTVR) offers multiple simultaneous views and spatial definition of intracardiac structures superior to that attainable by 2-dimensional transthoracic echocardiography (2D-TE). We hypothesized that RT-3D-TE would therefore improve identification of left ventricular apical thrombi (LVT). METHODS: Patients were referred to our echocardiography laboratory over an 8-month period. Those diagnosed with a "suspicious" or "definite" LVT on the basis of 2D-TE images underwent RT-3D-TE on the same day. All 2D-TE, RT-3D-TE, and RTVR images were reviewed by 2 independent observers. RT-3D-TE findings were considered positive for LVT if LVT was visualized in both B-scan (apical orthogonal) and C-scan (short axis, with and without tilting angle) planes and on RTVR images, nondiagnostic (or suspicious) for LVT if it was not visualized in all planes, and negative for LVT if it was not visualized in any plane. RESULTS: Thirty patients (19 men and 11 women) with a mean age (+/- standard deviation) of 52 +/- 13 years were enrolled. The interobserver agreement coefficient was 63% for 2D-TE interpretations of LVT and 93% for RT-3D-TE interpretations of LVT (p<0.05). The final interpretations by RT-3D-TE with RTVR were positive for LVT in 16 patients (53%), suspicious for LVT in 4 patients (13%), and negative for LVT in 10 patients (30%). CONCLUSIONS: RT-3D-TE with RTVR offers dramatically clearer echocardiographic findings than does 2D-TE. In particular, RT-3D-TE is able to provide a clear diagnosis of LVT/non-LVT when 2D-TE images are merely suggestive of the disorder. Therefore, RT-3D-TE with RTVR, which is a clinically feasible alternative to 2-dimensional echocardiography, has great potential to positively affect the diagnosis, follow-up, and care of patients with suspected LVT.