Which is not a finding in a massive left sided pneumothorax?

The ECG pattern in the left sided group has been more conspicuous and more striking, and has consisted of a lower voltage of QRS-1, flattening of T waves in Lead 1, a change in the contour of QRS complexes in the chest leads, and a definite inversion of T waves in the chest leads; these T wave inversions being the most constant and conspicuous of all changes. There will be right axis detion with Q waves in the anterior leads. It may mimic acute myocardial infarction. The ECG pattern in the right sided group has been mainly depression of QRS-1, and depression of P waves in the limb leads. T inversion has been notably absent.