To the editor: We read with interest the article by Mascherbauer et al1 recently published in Heart and we congratulate our colleagues for an honest effort on shedding some light on an important problem which is still generating some controversy.

Nonetheless, based on the title and the conclusions of both the abstract and the paper, we are concerned that the paper may unfortunately convey the wrong message—that is, that moderate prosthesis–patient mismatch (PPM) should never be a concern in patients undergoing aortic valve replacement. Moreover, from the introduction, justification for the study appears to be based on the perception that our previous papers were recommending “that even left ventricular outflow tract enlargement may be justified to prevent moderate PPM”. We have never made such an unqualified recommendation. Indeed, our findings as well as those of others2 show that the impact of moderate PPM on outcomes is most significant in patients with left ventricular …