title: Characterization of Cardiac Amyloidosis by Atrial Late Gadolinium Enhancement Using Contrast-Enhanced Cardiac Magnetic Resonance Imaging and Correlation With Left Atrial Conduit and Contractile Function.
abstract: The diagnosis of cardiac amyloidosis (CA) often necessitates invasive myocardial biopsy. We sought to evaluate whether late gadolinium enhancement (LGE) of the atrial myocardium by cardiac magnetic resonance imaging was associated with impaired left atrial (LA) function and whether the extent of LA LGE may enhance diagnostic differentiation of CA from other cardiomyopathies. Twenty-two patients with biopsy-proven CA, 37 with systemic hypertension (SH), and 22 with nonischemic dilated cardiomyopathy (NIDC) underwent cardiac magnetic resonance imaging and echocardiographic evaluation. Patients with CA had greater minimal LA volume (57 ± 53 vs 24 ± 18 in SH and 19 ± 25% in NIDC, p = 0.003), and significantly lower total LA emptying function (19 ± 14 vs 40 ± 14 in SH and 33 ± 20% in NIDC, p = 0.0006). The mean proportion of atrial enhancement (LGELA%) was significantly greater in patients with CA than with SH and NIDC (59 ± 36% vs 7.4 ± 2.1 and 2.9 ± 9.0%, p <0.0001, respectively). There was also a strong inverse correlation between both active and total atrial emptying (r = -0.69, p = 0.001; r = -0.67, p = 0.01, respectively) with LGELA% for patients with CA. In multivariate regression analysis, LGELA% was the strongest adjusted predictor for CA diagnosis. Using receiver operating characteristic analysis, LGELA% ≥33% produced the greatest diagnostic utility for CA (sensitivity 76%, specificity 94%). Patients with CA may have extensive LGE of the LA myocardium, which is associated with marked reduction in LA emptying function. The extent of LA LGE was highly predictive for the diagnosis of CA.
authors.affiliation: Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts. Electronic address: rykwong@partners.org.
authors.forename: Raymond Y
authors.initials: RY
authors.lastname: Kwong
authors.affiliation: Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Bobak
authors.initials: B
authors.lastname: Heydari
authors.affiliation: Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Siddique
authors.initials: S
authors.lastname: Abbasi
authors.affiliation: Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Kevin
authors.initials: K
authors.lastname: Steel
authors.affiliation: Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Mouaz
authors.initials: M
authors.lastname: Al-Mallah
authors.affiliation: Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Henry
authors.initials: H
authors.lastname: Wu
authors.affiliation: Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Rodney H
authors.initials: RH
authors.lastname: Falk
mesh_terms: D000368:Aged; D000686:Amyloidosis / Q000175:diagnosis*; D016279:Atrial Function, Left / Q000502:physiology*; D009202:Cardiomyopathies / Q000175:diagnosis*; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA