title: Echocardiography-based spectrum of severe tricuspid regurgitation: the frequency of apparently idiopathic tricuspid regurgitation.
abstract: BACKGROUND
  The cause of tricuspid valve (TV) regurgitation (TR) occasionally remains unclear. The objectives of our study were to define the causal spectrum of severe TR diagnosed by echocardiography at a tertiary medical center and to assess the relative frequency and determine the clinical and echocardiographic characteristics of TR without an apparent cause (idiopathic TR).
  
  
  METHODS
  Consecutive patients with severe TR were identified by the echocardiography laboratory computerized database. The echocardiographic reports of all patients were reviewed and the causes of TR were determined. The echocardiographic studies and medical charts were reviewed in patients without an obvious cause of TR.
  
  
  RESULTS
  Of 242 consecutive patients diagnosed with severe TR, organic TV disease was evident in 23 patients (9.5%) and significant pulmonary hypertension (estimated pulmonary artery systolic pressure > 50 mm Hg) in an additional 157 patients (64.9%). After further excluding patients with various confounding factors, possibly associated with occult organic TV disease or significant pulmonary hypertension, 23 patients (9.5%) had severe TR without an apparent cause. Of these, TV coaptation appeared relatively intact, allowing adequate estimation of pulmonary artery pressure, in 15 patients (6.2% of all patients with severe TR; idiopathic TR group). Patients with idiopathic TR were older (76 +/- 10 years), with a high frequency of atrial fibrillation (93%), and prominent TV annular dilatation.
  
  
  CONCLUSIONS
  After excluding multiple potential causes of TR, severe TR is occasionally idiopathic. Annular dilatation (secondary to aging, atrial fibrillation, or other causes) is the likely mechanism of TR in these patients.
authors.affiliation: Echocardiography Laboratory and Heart Valves Clinic, Department of Cardiology, Rambam Health Care Campus and the Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: Diab
authors.initials: D
authors.lastname: Mutlak
authors.forename: Jonathan
authors.initials: J
authors.lastname: Lessick
authors.forename: Shimon A
authors.initials: SA
authors.lastname: Reisner
authors.forename: Doron
authors.initials: D
authors.lastname: Aronson
authors.forename: Salim
authors.initials: S
authors.lastname: Dabbah
authors.forename: Yoram
authors.initials: Y
authors.lastname: Agmon
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004452:Echocardiography / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011669:Pulmonary Wedge Pressure; D012720:Severity of Illness Index; D014261:Tricuspid Valve / Q000000981:diagnostic imaging* / Q000503:physiopathology; D014262:Tricuspid Valve Insufficiency / Q000000981:diagnostic imaging* / Q000503:physiopathology; D016277:Ventricular Function, Left / Q000502:physiology; D016278:Ventricular Function, Right / Q000502:physiology