The primary non-invasive imaging technique for the diagnosis of arrhythmias is the ECHO, also safe in pregnant women.  Other imaging studies should be performed in case of inability to obtain sufficient diagnostic information in ECHO, because of the cost, availability and worse side effects (class of recommendation IIaB by AHA/ACC/ESC).  Among these studies is the study of magnetic resonance imaging "gold standard" for assessing the anatomy and function of the heart, allows the assessment of myocardial structure and can significantly supplement the information obtained in the study of ECHO, is also safe in pregnant women.
ECHO