title: Prognostic value of left atrial function in systemic light-chain amyloidosis: a cardiac magnetic resonance study.
abstract: BACKGROUND
  Cardiac involvement in systemic light-chain amyloidosis (AL) imparts an adverse impact on outcome. The left atrium (LA), by virtue of its anatomical location and muscular wall, is commonly affected by the amyloid process. Although LA infiltration by amyloid fibrils leads to a reduction in its pump function, the infiltration of the left ventricular (LV) myocardium results in diastolic dysfunction with subsequent increase in filling pressures and LA enlargement. Even though left atrial volume (LAV) is an independent prognostic marker in many cardiomyopathies, its value in amyloid heart disease remains to be determined. In addition, few data are available as to the prognostic value of LA function in systemic AL. Using cardiac magnetic resonance (CMR), the current study aims to assess the prognostic significance of the maximal LAV and total LA emptying fraction (LAEF) in patients with AL.
  
  
  RESULTS
  Fifty-four consecutive patients (age 66 ± 10 years, 59% males) with confirmed systemic AL and mean LV ejection fraction of 60 ± 12% underwent CMR. As compared with patients with no or minimal cardiac involvement (Mayo Clinic [MC] stage I), those at moderate and high risk (MC stages II and III) had significantly larger indexed maximal LAV (36 ± 15 vs. 46 ± 13 vs. 52 ± 19 mL/m(2), P = 0.03) and indexed minimal LAV (20 ± 6 vs. 34 ± 11 vs. 44 ± 17 mL/m(2), P < 0.001), lower LAEF (42 ± 9 vs. 26 ± 13 vs. 16 ± 9%, P < 0.0001) but similar LVEF. Furthermore, myocardial late gadolinium enhancement (LGE) was more frequent and significantly associated with lower LAEF. LAEF was also significantly lower in symptomatic (NHYA ≥ II, 22 ± 14%) as compared with asymptomatic patients (NYHA class I, 33 ± 13%, P = 0.006). Two-year survival rate was lower in patients with LAEF ≤ 16% as compared with those with LAEF > 16% (37 ± 11 vs. 94 ± 4%, P = 0.001). In multivariate analysis, lower LAEF remained independently associated with a higher risk of 2-year mortality (HR = 1.08 per 1% decrease, 95% CI: 1.02-1.15, P = 0.003).
  
  
  CONCLUSIONS
  In patients with systemic AL, LAEF as assessed by CMR is associated with NYHA functional class, MC stage, myocardial LGE and 2-year mortality.
authors.affiliation: CHU Dupuytren, Limoges, France French National Reference Center for Light chains Amyloidosis and Other Diseases by Monoclonal Immunoglobulin Deposits, Limoges University, Limoges, France dania.mohty@chu-limoges.fr.
authors.forename: Dania
authors.initials: D
authors.lastname: Mohty
authors.affiliation: CHU Dupuytren, Limoges, France.
authors.forename: Cyrille
authors.initials: C
authors.lastname: Boulogne
authors.affiliation: CHU Dupuytren, Limoges, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Magne
authors.affiliation: CHU de la Milétrie, Poitiers, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Varroud-Vial
authors.affiliation: CHU Dupuytren, Limoges, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Martin
authors.affiliation: CHU Dupuytren, Limoges, France.
authors.forename: Hind
authors.initials: H
authors.lastname: Ettaif
authors.affiliation: King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia.
authors.forename: Bahaa M
authors.initials: BM
authors.lastname: Fadel
authors.affiliation: CHU de la Milétrie, Poitiers, France.
authors.forename: Frank
authors.initials: F
authors.lastname: Bridoux
authors.affiliation: CHU Dupuytren, Limoges, France.
authors.forename: Victor
authors.initials: V
authors.lastname: Aboyans
authors.affiliation: CHU Henri Mondor, Créteil, France.
authors.forename: Thibaud
authors.initials: T
authors.lastname: Damy
authors.affiliation: CHU Dupuytren, Limoges, France French National Reference Center for Light chains Amyloidosis and Other Diseases by Monoclonal Immunoglobulin Deposits, Limoges University, Limoges, France.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Jaccard
mesh_terms: D000367:Age Factors; D000368:Aged; D000686:Amyloidosis / Q000000981:diagnostic imaging* / Q000401:mortality / Q000503:physiopathology; D000704:Analysis of Variance; D009202:Cardiomyopathies / Q000000981:diagnostic imaging* / Q000401:mortality / Q000503:physiopathology; D015331:Cohort Studies; D016001:Confidence Intervals; D016208:Databases, Factual; D005260:Female; D005602:France; D006325:Heart Atria / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007147:Immunoglobulin Light Chains / Q000097:blood; D000075363:Immunoglobulin Light-chain Amyloidosis; D053208:Kaplan-Meier Estimate; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012372:ROC Curve; D018570:Risk Assessment; D012720:Severity of Illness Index; D012737:Sex Factors; D013318:Stroke Volume / Q000502:physiology*; D016019:Survival Analysis
chemical_list: D007147:Immunoglobulin Light Chains
keywords: AL amyloidosis; Cardiac magnetic resonance; Left atrial function; Prognosis