Electrocardiographic findings in children with spinal muscular atrophy.

Most of the patients in this study with spinal muscular atrophy were found to have tremors of the isoelectric line in the electrocardiogram (ECG) tracings. There were a total of 47 cases of SMA (mean age 40.8 months). All three types of SMA had a similar incidence (about 80%) of tremors in the tracings (p = 0.885). In 7 cases the ECG tremors had an intermittent pattern. ECG tremors were commonly found in the majority of SMA patients and this finding, though non-specific, may suggest a possible SMA diagnosis.