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Nappi and colleagues1Nappi F. Avtaar Singh S.S. Gentile F. Pathophysiologic mechanisms of subvalvular repair and its clinical implications (letter).Ann Thorac Surg. 2020; 110: 344-345Abstract Full Text Full Text PDF Scopus (1) Google Scholar are to be congratulated for their outstanding 5-year results following papillary muscle approximation, restrictive annuloplasty, and coronary artery bypass graft (CABG) for severe ischemic mitral regurgitation (IMR). This is the lowest reported prevalence of recurrent IMR. Remember, the MitraClip trials were not without clinical concerns. Within 1 year of the MitraClip procedure, 30% to 50% of patients either died or continued to have symptoms that required hospitalization for heart failure.2Stone G.W. Lindenfeld J. Abraham W.T. et al.COAPT Investigators. Transcatheter mitral valve repair in patients with heart failure.N Engl J Med. 2018; 379: 2307-2318Crossref PubMed Scopus (1347) Google Scholar,3Obadia J.F. Messika-Zeitoun D. Leurent G. et al.Percutaneous repair or medical treatment for secondary mitral regurgitation.N Engl J Med. 2018; 379 (2297-2230)Crossref PubMed Scopus (893) Google Scholar In my editorial,4Michler R.E. Learning from controversy: management of severe ischemic mitral regurgitation at the time of CABG.Ann Thorac Surg. 2019; 108: 321-323Abstract Full Text Full Text PDF PubMed Scopus (9) Google Scholar I sought to convey to surgeons a practical approach to selecting a specific mitral valve (MV) procedure for a given clinical condition. Our growing understanding of the relationship between the clinical parameters of IMR severity, left ventricle (LV) geometry (size and shape) and LV function (global and regional) help the surgeon to better select a specific surgical therapy. As Nappi and colleagues note,5Nappi F. Lusini M. Spadaccio C. et al.Papillary muscle approximation versus restrictive annuloplasty alone for severe ischemic mitral regurgitation.J Am Coll Cardiol. 2016; 67: 2334-2346Crossref PubMed Scopus (124) Google Scholar it may be time to revisit a trial of severe IMR through the eyes of this evolving conceptual model and compare MV replacement to a “complete mitral repair” (annular plus subvalvular) to a MitraClip. In the opinion of this author, this would be a difficult trial to launch. The patient populations enrolled in COAPT and MITRA-FR, unlike the surgical trials of IMR,5Nappi F. Lusini M. Spadaccio C. et al.Papillary muscle approximation versus restrictive annuloplasty alone for severe ischemic mitral regurgitation.J Am Coll Cardiol. 2016; 67: 2334-2346Crossref PubMed Scopus (124) Google Scholar did not need CABG. This fact is also a reason why the MitraClip trial data cannot be extended to treat patients with severe IMR and coronary artery disease in need of revascularization. The known benefits of revascularization in improving regional and global LV function, and in turn IMR, will elicit strong opposing opinions among trialists regarding any proposed study comparing CABG plus MV surgery against percutaneous coronary intervention (PCI) plus MitraClip. Nevertheless, perhaps an exacting trial could be negotiated and well designed to evaluate patients with precisely defined severe IMR and coronary artery disease amenable to both PCI and CABG and, as probably will be required, in patients with non–severely dilated ventricles. Until the time that such a trial can be completed, patients with severe IMR and coronary artery disease amenable to CABG should undergo surgery to experience the established benefits of CABG together with an MV procedure (MV replacement or a “complete mitral repair”) that is selected on the basis of a thorough evaluation of the patient’s LV geometry and function. Pathophysiologic Mechanisms of Subvalvular Repair and Its Clinical ImplicationsThe Annals of Thoracic SurgeryVol. 110Issue 1PreviewThe observations by Dr Michler,1 as well as by our group, should provide food for thought and potentially lead to revisiting the randomized clinical trials published on the subject that require another type of surgical comparison: a “complete mitral repair” (ie, involving both the valvular apparatus and subvalvular)2 vs chordal-sparing mitral replacement3 and the Mitraclip (Abbott Vascular, Santa Clara, CA) procedure.4,5 Full-Text PDF