New ECG/CT Technique Pinpoints Cause of Abnormal Heartbeat

August 31, 2011

A new technique combining electrocardiographs (ECG) and computed tomography (CT) paints a more accurate picture of the electrical activity of a beating heart, according to a new study. The technique, which its inventors call electrocardiographic imaging, or ECGI, can pinpoint the precise origins of abnormal heart rhythms and could improve diagnosis and treatment of this fatal condition.

A new technique combining electrocardiographs (ECG) and computed tomography (CT) paints a more accurate picture of the electrical activity of a beating heart, according to a new study in Science Translational Medicine. The technique, which its inventors call electrocardiographic imaging, or ECGI, can pinpoint the precise origins of abnormal heart rhythms and could improve diagnosis and treatment of this fatal condition, University of Washington in St. Louis researchers reported.

More than 7 million people worldwide die annually from abnormal heart rhythms or cardiac arrhythmias, and many more are disabled. Yet there has been no imaging technique available to identify patients at risk, provide accurate diagnosis, or guide therapy. The electrocardiogram, a decades-old tool for measuring the electrical activity of the heart, captures only an approximate, distorted view of a beating heart.

Combining ECG recorded using multi-electrode vests with torso CT scans, Yong Wang, PhD, and colleagues pinpointed the origins of abnormal heartbeats in 25 patients. The authors combined the inputs to understand the electrical behavior of arrhythmic hearts, creating a detailed map of electrical activation and tracing the origin of the abnormal heart rhythm.

The team correctly identified the origin of rhythms in more than 90 percent of patients, they reported. Wang and colleagues confirmed these results with the standard catheter-based electrophysiology study.

The results show that an ECGI can give doctors information comparable to the current procedure for mapping abnormal heart activity without the need for intravenous needles or anesthetics. Moreover, the ECG/CT approach enables the mapping of single heartbeats and give high-resolution images of the heart’s ventricles, an improvement over the simplified shadow that standard techniques provide.