title: Total thyroidectomy in patients with amiodarone-induced thyrotoxicosis and severe left ventricular systolic dysfunction.
abstract: BACKGROUND
  Patients with amiodarone-induced thyrotoxicosis (AIT) and left ventricular (LV) systolic dysfunction have a high mortality rate. Usually, medical therapy is the first choice for AIT patients, whereas the role of the thyroidectomy is unsettled.
  
  
  OBJECTIVE
  The objective of the study was to evaluate the effect of a total thyroidectomy on cardiac function and survival of AIT patients with severe LV systolic dysfunction.
  
  
  METHODS
  This was a retrospective cohort study.
  
  
  METHODS
  The study was conducted at a tertiary university center.
  
  
  METHODS
  All AIT patients (n=24; nine patients with type 1 AIT, 15 patients with type 2 AIT) referred to the Department of Endocrinology and submitted to a total thyroidectomy at the Department of Surgery, both at the University of Pisa, during the years 1997-2010.
  
  
  METHODS
  The intervention was a total thyroidectomy.
  
  
  METHODS
  LV ejection fraction (EF) after the thyroidectomy and survival in December 2011 were measured.
  
  
  RESULTS
  All enrolled patients had previously undergone to medical treatment for AIT, as appropriate, without achieving euthyroidism. Patients with moderate to severe LV systolic dysfunction (EF<40%, group 1, n=9) or with mild systolic dysfunction (40%≤EF≤50%, group 2, n=5) were compared with patients with normal systolic function (EF>50%, group 3, n=10). Two months after thyroidectomy, under levothyroxine replacement therapy, LVEF improved in patients with LV systolic dysfunction, particularly in those of group 1, in whom it increased from 28.2±7.2 to 38.3±6% (P=0.007). On the contrary, LVEF did not significantly change in group 3 (from 57.1±3.0 to 59.8±6.6%, P=0.242). The mean follow-up was 67±42 months. No death occurred during and 2 months after surgery. One death occurred in one patient of group 1, 30 months after the thyroidectomy, due to acute myocardial infarction. No patient had relevant complications of thyroidectomy.
  
  
  CONCLUSIONS
  Total thyroidectomy, by rapidly restoring euthyroidism, may improve cardiac function and reduce the risk of mortality in AIT patients with severe LV dysfunction.
authors.affiliation: Department of Endocrinology and Metabolism, University of Pisa, Ospedale Cisanello, Via Paradisa, 2, 56124 Pisa, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Tomisti
authors.forename: Gabriele
authors.initials: G
authors.lastname: Materazzi
authors.forename: Luigi
authors.initials: L
authors.lastname: Bartalena
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Rossi
authors.forename: Angelica
authors.initials: A
authors.lastname: Marchello
authors.forename: Manuela
authors.initials: M
authors.lastname: Moretti
authors.forename: Luigi
authors.initials: L
authors.lastname: De Napoli
authors.forename: Rita
authors.initials: R
authors.lastname: Mariotti
authors.forename: Paolo
authors.initials: P
authors.lastname: Miccoli
authors.forename: Enio
authors.initials: E
authors.lastname: Martino
authors.forename: Fausto
authors.initials: F
authors.lastname: Bogazzi
mesh_terms: D000368:Aged; D000638:Amiodarone / Q000009:adverse effects*; D000889:Anti-Arrhythmia Agents / Q000009:adverse effects; D005260:Female; D006331:Heart Diseases / Q000188:drug therapy / Q000401:mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000401:mortality; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D013318:Stroke Volume; D013599:Systole; D013965:Thyroidectomy / Q000379:methods* / Q000401:mortality; D013971:Thyrotoxicosis / Q000139:chemically induced / Q000401:mortality / Q000601:surgery; D014665:Vasodilator Agents / Q000009:adverse effects; D018487:Ventricular Dysfunction, Left / Q000401:mortality*
chemical_list: D000889:Anti-Arrhythmia Agents; D014665:Vasodilator Agents; D000638:Amiodarone