CAVIAR - A TOOL TO IMPROVE SERIAL ANALYSIS OF THE 12-LEAD ELECTROCARDIOGRAM

An important part of an electrocardiogram (EGG) interpretation is the comparison between the present ECG and earlier recordings. The purpose of the present study was to evaluate a combination of two computer-ba sed methods, synthesized vectorcardiogram (VCG) and CAVIAR, in this co mparison. The methods were applied to a group of 38 normal subjects an d to a group of 36 patients treated with anthracyclines. A fraction of these patients are likely to develop cardiac injury during or after t he treatment, since anthracyclines are known to cause heart failure an d cardiomyopathy. Two ECGs were recorded on each patient; one before a nd one after the treatment. On each normal subject, two ECGs were reco rded with an interval of 8-9 years. A synthesized VCG was calculated f rom each ECG and the two synthesized VCGs from each subject were analy sed with the CAVIAR-method. The CAVIAR analysis is a quantitative meth od and normal limits for four measurements were established using the normal group. Values above these limits were more frequent in the pati ent group than in the normal group, The conventional ECGs were also an alysed visually by an experienced ECG interpreter without knowledge of the result of the CAVIAR analysis. No significant serial changes were found in 10 of the patients with high CAVIAR values. Changes in the E CGs were found in two patients with normal CAVIAR values. In summary, synthesized VCG and CAVIAR could be used to highlight small serial cha nges that are difficult to find in a visual analysis of ECGs.