Researchers have used an ultrasound technique they pioneered a decade ago — electromechanical wave imaging (EWI) — to accurately localize atrial and ventricular cardiac arrhythmias in adult patients in a double-blinded clinical study. They evaluated the accuracy of EWI for localization of various arrhythmias in all four chambers of the heart prior to catheter ablation: the results showed that EWI correctly predicted 96% of arrhythmia locations as compared with 71% for 12-lead ECGs.