title: Thyroid hormone, amiodarone therapy, and prognosis in left ventricular systolic dysfunction.
abstract: BACKGROUND
  Amiodarone protects patients with left ventricular systolic dysfunction (LVSD) against serious arrhythmias, but it also has numerous side effects on non-cardiac organs, such as the thyroid. Indeed, amiodarone may inhibit the peripheral conversion of T₄ into T₃. Pathologically reduced serum levels of T₃ - the so-called "low T₃ syndrome" (LOWT3) - increase mortality in patients with LVSD and not on amiodarone.
  
  
  OBJECTIVE
  The aim of the study was to examine the relationship between thyroid hormone status, amiodarone therapy, and outcome in a population with LVSD. MATERIAL/ SUBJECTS AND METHODS: A total of 2344 patients with LVSD and free of overt hyper- and hypothyroidism were enrolled. The population was divided into 4 groups: group 1 (LOWT3 and amiodarone therapy, no.=126), group 2 (isolated amiodarone therapy, no.=74), group 3 (isolated LOWT3, no.=682), group 4 (controls, no.=1462).
  
  
  RESULTS
  Kaplan-Meier curves showed, after a mean follow-up of 31 months, increased total and cardiac mortality in groups 1 (30% and 20%, respectively), 2 (23%, 11%), and 3 (22%, 12%) compared to group 4 (total mortality log-rank 82.8, p<0.0001; cardiac mortality log-rank 63.1, p<0.0001). At Cox analysis, adjusted for several clinical variables, survival was reduced in groups 1 and 3 compared to group 4. Group 2 had a similar mortality to group 4, although the number of patients was too limited to accurately assess the effect of amiodarone on long-term prognosis.
  
  
  CONCLUSIONS
  LOWT3 exerts an adverse impact on prognosis in LVSD, which is not influenced by concomitant amiodarone therapy.
authors.affiliation: Fondazione G. Monasterio CNR - Regione Toscana, Pisa, Italy. michecoc@ifc.cnr.it
authors.forename: M
authors.initials: M
authors.lastname: Coceani
authors.forename: S
authors.initials: S
authors.lastname: Molinaro
authors.forename: M
authors.initials: M
authors.lastname: Scalese
authors.forename: P
authors.initials: P
authors.lastname: Landi
authors.forename: C
authors.initials: C
authors.lastname: Carpeggiani
authors.forename: A
authors.initials: A
authors.lastname: L'abbate
authors.forename: G
authors.initials: G
authors.lastname: Iervasi
authors.forename: A
authors.initials: A
authors.lastname: Pingitore
mesh_terms: D000368:Aged; D000638:Amiodarone / Q000627:therapeutic use*; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D001145:Arrhythmias, Cardiac / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality; D016022:Case-Control Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007037:Hypothyroidism / Q000175:diagnosis / Q000378:metabolism / Q000401:mortality; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015996:Survival Rate; D013961:Thyroid Gland / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D013963:Thyroid Hormones / Q000378:metabolism*; D018487:Ventricular Dysfunction, Left / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality
chemical_list: D000889:Anti-Arrhythmia Agents; D013963:Thyroid Hormones; D000638:Amiodarone