Search

Background: Tissue synchronizing imaging (TSI) allows visual detection of asynchronous myocardial contraction. Although it is a screening tool for the detection of left ventricular (LV) dyssynchrony, its use as a qualitative method to assess dyssynchrony has not been studied. We evaluated the correlation of the visual assessment of dyssynchrony using TSI with quantitative assessment, the value of visual assessment to predict reverse remodeling to cardiac resynchronization therapy (CRT). Methods: Echocardiograms from 100 consecutive patients were retrospectively evaluated. We compared visual TSI assessment with the qualitative assessment of dyssynchrony obtained by tissue Doppler imaging (TDI). The utility of visual assessment as a predictor of response to CRT was evaluated in 43 patients. Results: In 86% of the cases, visual assessment was possible, and reproducibility was unrelated to observer experience. Each grade of visual dyssynchrony corresponded to a range of values of time to peak velocity (TPV) gradient (p < 0.001). Grade ≥1 dyssynchrony by visual assessment had 90% sensitivity and 95% specificity to identify ≥65 ms TPV gradient of LV opposing walls, and 93% sensitivity and 70% specificity to predict reverse LV remodeling. Conclusion: LV dyssynchrony may be visually assessed by TSI, which can also predict reverse LV remodeling.

Background: Early diagnosis of ischemia is complicated by the poor sensitivity of standard tests and contraindication for stress testing in unstable angina patients. Magnetocardiography (MCG) imaging can be used for the rapid, non-invasive detection of ischemia at rest. Methods: We studied 125 patients with presumed ischemic chest pain. All were chest pain free at the time of scanning. A 6-minute resting MCG scan (CardioMag Imaging, Inc., New York, 9-channel system) was performed. Following the MCG scan, automated software data analysis was performed, and quantitative scores were automatically calculated for each subject. The presence of ischemia was determined after testing with serial troponins, stress testing, and/or coronary angiography. Results: The mean age was 59.4 ± 13.6 years. Most patients (86.4%) had non-ischemic 12-lead ECG and normal troponin (86.2%). Fifty-five patients (44.0%) were determined to be ischemic. The MCG sensitivity, specificity, positive and negative predictive value was 76.4, 74.3, 70.0 and 80.0%, respectively, for the detection of ischemia (p < 0.0001). Conclusions: MCG is a new rapid, non-invasive imaging tool able to detect repolarization abnormalities at rest consistent with ischemia in patients presenting with chest pain syndrome and normal or non-specific 12-lead ECG and normal troponin.