BACKGROUND The association, if any, between the effective regurgitant orifice (EROA) to left ventricular end-diastolic volume (LVEDV) ratio and 1-year mortality is controversial in patients undergoing mitral transcatheter edge-to-edge repair (m-TEER) with the MitraClip™ system. The objective is to determine the association between EROA/LVEDV and 1-year mortality among patients undergoing m-TEER with MitraClip™. METHODS In patients with severe secondary (functional) mitral regurgitation (MR), we analyzed registry data from 11 centers using generalized linear models with the generalized estimating equations approach. RESULTS We studied 525 patients with secondary MR who underwent m-TEER in 11 centers. Most patients were male (63%) and were NYHA class III (61%) or IV (21%). MR was caused by ischemic cardiomyopathy in 51% of patients. EROA/LVEDV values varied widely with median=0.19 mm2/mL, interquartile range [0.12,0.28] mm2/mL, and 187 (36%) patients had values <0.15 mm2/mL. Post-procedural MR severity improved substantially, being 1+ or less in 74%, 2+ in 20%, 3+ in 4%, and 4+ in 2%. 1-year mortality was 22%. After adjustment for confounders, the logarithmic transformation of EROA/LVEDV was associated with 1-year mortality (odds ratio=0.600, 95% confidence interval [0.386,0.933], p=0.023). A higher Society of Thoracic Surgeons risk score was also associated with increased mortality. CONCLUSIONS Lower values of Ln(EROA/LVEDV) were associated with increased 1-year mortality in a multi-center registry. The slope of the association is steep at low values, but gradually becomes flatter as Ln(EROA/LVEDV) increases.

Christopher P Kovach MD - No disclosures to report. D Scott Lim MD - Dr Lim receives institutional grants from Abbott, Boston Scientific, Corvia, Edwards, Medtronic, and Trisol. He is a consultant for Philips, Valgen, and Venus. Deepa Raghunathan MD - No disclosures to report. Edward A Gill MD - No disclosures to report. Enrique Garcia-Sayan MD - No disclosures to report. Evelio Rodriguez MD - Dr. Rodriguez is a consultant and speaker for Abbott. He receives research funding from Abbott. Firas E Zahr MD - Dr. Zahr is a consultant and on the advisory board for Medtronic. He receives educational and research grants from Medtronic and Edwards. He receives educational grants from Siemens. Flora M Li MD - No disclosures to report. Gorav Ailawadi MD - Dr. Ailawadi is a consultant for Medtronic, Abbott, Edwards, Gore, Anteris, Atricure, CryoLife, Philips, Johnson & Johnson Graciela B Mentz PhD - No disclosures to report. Jason H Rogers MD - Dr. Rogers receives research/institutional grants from Abbott and Boston Scientific. He is a consultant for Abbott, Baylis, and Boston Scientific. Lily Chen MD - Dr. Chen is a consultant for Philips, Abbott, and Akura Medical. M Andrew Morse MD - Dr Morse previously served as a consultant for Abbott. Mani A Vannan MD - Dr Vannan receives research support and speakers bureau from Abbott - all payments to the Piedmont Heart Institute, not to self. Marcella A Calfon Press MD, PhD - No disclosures to report. Mark Reisman MD - No disclosures to report. Michael Morcos MD - No disclosures to report. Milo C Engoren MD - No disclosures to report. Neal M Duggal MD - No disclosures to report Nishtha Sodhi MD - Dr. Sodhi is a consultant for Medtronic and Boston Scientific. Paul Sorajja MD - Dr. Sorajja is a consultant for 4C Medical, Anteris, Abbott Structural, Boston Scientific, Edwards Lifesciences, Evolution Medical, Foldax, GLG, Medtronic, Phillips, Siemens, Shifamed, WL Gore, vDyne, xDot. Pradeep K Yadav MD - Dr. Yadav is consultant and speaker for Edwards Lifesciences, Abbott Vascular, Boston Scientific. He sits on the advisory board for Dasi Simulations. Scott M Chadderdon MD - Dr Chadderdon is a consultant for Medtronic and Edwards. He receives a research grant from GE Healthcare. Stanley J Chetcuti MD - Dr. Chetcuti is a consultant for Medtronic and Boston Scientific. He receives research grants from Jena, Abbott, Edwards, Gore , Medtronic and Boston Scientific. Yuan Yuan MS - No disclosures to report.

No funding was received for this work.

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This study received a certificate of exemption from the University of Michigan Institutional Review Board (HUM00191906, Ann Arbor, MI). As no patient care interventions were involved, signed patient consent was waived.

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Study data was collected via combined queries from each participating institution's electronic medical record and the Society of Thoracic Surgeons (STS) & American College of Cardiology (ACC) Transcatheter Valve Therapy (TVT) Registry. Echocardiographic data were reviewed by each of the participating sites.