title: Parathyroidectomy eliminates arrhythmic risk in primary hyperparathyroidism, as evaluated by exercise test.
abstract: OBJECTIVE
  To investigate whether parathyroidectomy (PTx) reverses risk factors for arrhythmias related to the QT dynamic changes evaluated during bicycle ergometry exercise test (ET).
  
  
  METHODS
  Twenty-four postmenopausal women with primary hyperparathyroidism (PHPT) (mean age 60.08.4 years) and 30 sex- and age-matched controls underwent ET, echocardiography, and biochemical evaluation. The following stages were considered during ET: rest, peak exercise, and recovery. The patients were randomized to two groups: 12 underwent PTx (group A) and 12 were followed-up conservatively (group B). After 6 months, the patients were studied again.
  
  
  RESULTS
  Groups A and B showed no differences in mean baseline biochemical values, echocardiographic parameters, and QTC interval. PHPT patients showed an increased occurrence of ventricular premature beats (VPBS) during ET compared with controls (37.0 vs 6.6%, P=0.03). Serum calcium level was a predictor of VPBS (P=0.05). Mean value of QTC was in the normal range at baseline (Group A: 401±16.9; group B: 402.25±13.5 ms) but significantly lower than controls (417.8±25.1 ms, P<0.01). A negative correlation was found between QTc and calcium values (P=0.03). Physiological reduction of QTc interval from rest to peak exercise was not observed in PHPT patients before surgery. After PTx, group A had a significant reduction in VPBs compared with baseline (at baseline, 5 of 12 vs none of 12 patients after PTx, P=0.03) and a restored normal QT adaptation during ET. Group B showed no significant changes after a 6-month period.
  
  
  CONCLUSIONS
  PTx reduces the occurrence of VPBs and restored the QTc adaptation during ET.
authors.affiliation: Department of Internal Medicine and Medical Disciplines, Sapienza University of Rome, Viale del Policlinico 155, 00161 Rome, Italy. jesspepe@tin.it
authors.forename: Jessica
authors.initials: J
authors.lastname: Pepe
authors.forename: Mario
authors.initials: M
authors.lastname: Curione
authors.forename: Sergio
authors.initials: S
authors.lastname: Morelli
authors.forename: Marisa
authors.initials: M
authors.lastname: Varrenti
authors.forename: Camillo
authors.initials: C
authors.lastname: Cammarota
authors.forename: Mirella
authors.initials: M
authors.lastname: Cilli
authors.forename: Sara
authors.initials: S
authors.lastname: Piemonte
authors.forename: Cristiana
authors.initials: C
authors.lastname: Cipriani
authors.forename: Claudio
authors.initials: C
authors.lastname: Savoriti
authors.forename: Orlando
authors.initials: O
authors.lastname: Raimo
authors.forename: Federica
authors.initials: F
authors.lastname: De Lucia
authors.forename: Luciano
authors.initials: L
authors.lastname: Colangelo
authors.forename: Carolina
authors.initials: C
authors.lastname: Clementelli
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Romagnoli
authors.forename: Salvatore
authors.initials: S
authors.lastname: Minisola
mesh_terms: D000368:Aged; D001145:Arrhythmias, Cardiac / Q000209:etiology / Q000517:prevention & control*; D004452:Echocardiography; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006801:Humans; D049950:Hyperparathyroidism, Primary / Q000150:complications / Q000503:physiopathology / Q000601:surgery*; D008875:Middle Aged; D016105:Parathyroidectomy; D018709:Statistics, Nonparametric; D018879:Ventricular Premature Complexes / Q000150:complications* / Q000503:physiopathology