title: Defining "severe" secondary mitral regurgitation: emphasizing an integrated approach.
abstract: Secondary mitral regurgitation (MR) is associated with poor outcomes, but its correction does not reverse the underlying left ventricular (LV) pathology or improve the prognosis. The recently published American Heart Association/American College of Cardiology guidelines on valvular heart disease generated considerable controversy by revising the definition of severe secondary MR from an effective regurgitant orifice area (EROA) of 0.4 to 0.2 cm(2), and from a regurgitant volume (RVol) of 60 to 30 ml. This paper reviews hydrodynamic determinants of MR severity, showing that EROA and RVol values associated with severe MR depend on LV volume. This explains disparities in the evidence associating a lower EROA threshold with suboptimal survival. Redefining MR severity purely on EROA or RVol may cause significant clinical problems. As the guidelines emphasize, defining severe MR requires careful integration of all echocardiographic and clinical data, as measurement of EROA is imprecise and poorly reproducible.
authors.affiliation: Baylor Heart and Vascular Institute, Dallas, Texas; Department of Internal Medicine, The Heart Hospital Baylor Plano, Plano, Texas. Electronic address: paulgr@baylorhealth.edu.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Grayburn
authors.affiliation: Department of Internal Medicine, Mount Sinai School of Medicine, New York, New York.
authors.forename: Blasé
authors.initials: B
authors.lastname: Carabello
authors.affiliation: Cardiology Division, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Judy
authors.initials: J
authors.lastname: Hung
authors.affiliation: Cardiovascular Medicine, Morristown Medical Center, Morristown, New Jersey.
authors.forename: Linda D
authors.initials: LD
authors.lastname: Gillam
authors.affiliation: Department of Internal Medicine, Stanford University Medical School, Stanford, California.
authors.forename: David
authors.initials: D
authors.lastname: Liang
authors.affiliation: Department of Cardiothoracic Surgery, The Heart Hospital Baylor Plano, Plano, Texas.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Mack
authors.affiliation: Bluhm Cardiovascular Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois.
authors.forename: Patrick M
authors.initials: PM
authors.lastname: McCarthy
authors.affiliation: Department of Cardiovascular Surgery, Stanford University Medical School, Stanford, California.
authors.forename: D Craig
authors.initials: DC
authors.lastname: Miller
authors.affiliation: Cedars-Sinai Heart Institute, Los Angeles, California.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Trento
authors.affiliation: Cedars-Sinai Heart Institute, Los Angeles, California.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Siegel
mesh_terms: D002306:Cardiac Volume; D004452:Echocardiography; D006352:Heart Ventricles; D006439:Hemodynamics; D006801:Humans; D008943:Mitral Valve / Q000503:physiopathology; D008944:Mitral Valve Insufficiency / Q000209:etiology / Q000503:physiopathology*; D012720:Severity of Illness Index
keywords: echocardiography; guidelines; hemodynamics; mitral valve; mitral valve insufficiency