Source:http://linkedlifedata.com/resource/umls/id/C1709789
NCI: A QS wave is an abnormal Q wave, and is an electrocardiographic finding. 'QS" wave or abnormal 'Q' wave in the right precordial leads, epicardial leads of the right ventricle and unipolar aVR lead with a high and relatively broad 'R' wave simulating an incomplete left bundle branch block without 'Q' waves in leads 1, aVL and left precordial leads - reciprocal and antagonistic aspects. (www.infarctcombat.org/abs.ghm-8.html)