title: The underlying causes of chordae tendinae rupture: a systematic review.
abstract: BACKGROUND
  The underlying causes of chordae tendinae rupture (CTR) and their frequencies vary. Different publications reached conflicting conclusions due to diverse definitions, different detection measures, and morbidity trends over time.
  
  
  METHODS
  Systematic literature review of unselected CTR series and underlying cause frequencies reanalysis.
  
  
  RESULTS
  Primary CTR overall rates before and since 1985 remain considerable (52.5% vs. 51.2%), yet median decreased (35% and 14%). Sub-acute endocarditis (SBE) and rheumatic heart disease (RHD) were the most frequent causes before 1985 (54.4% and 42.1%, respectively); since 1985 SBE and RHD have dropped sharply to 37.4% and 24.8%, respectively. Since 1985, mitral valve prolapse (MVP) and myxomatous degeneration (MD) have caused 44.5% and 11.7%, respectively. All other causes were almost not evident.
  
  
  CONCLUSIONS
  "Primary CTR" remains significant. MD may be underestimated, as microscopic evaluation was not routinely performed. MD is probably the most frequent underlying cause given it is also the underlying cause of MVP. MVP may be overestimated due to detection criteria and misinterpretation of leaflet prolapse. SBE, frequently coexistent with other underlying causes, may be overestimated either due to detection bias or being a consequence rather than CTR cause. RHD is expected to further decline, following rheumatic fever. Previous significant underlying causes proved to be episodic if at all causative, e.g., blunt chest trauma, generalized connective tissue disorder, ischemic heart disease, and other heart and valvular diseases. CTR can occur in apparently healthy subjects having no atypical appearance and who may be unaware of carrying risk.
authors.affiliation: Epidemiology Section, School of Public Health, Sackler School of Medicine, Tel Aviv University, Ramat Aviv, Israel. ugabai@post.tau.ac.il
authors.forename: Uri
authors.initials: U
authors.lastname: Gabbay
authors.forename: Chaim
authors.initials: C
authors.lastname: Yosefy
mesh_terms: D002815:Chordae Tendineae / Q000473:pathology*; D004698:Endocarditis, Subacute Bacterial / Q000150:complications* / Q000473:pathology; D006801:Humans; D008945:Mitral Valve Prolapse / Q000150:complications* / Q000473:pathology; D012214:Rheumatic Heart Disease / Q000150:complications* / Q000473:pathology; D012422:Rupture, Spontaneous / Q000209:etiology / Q000473:pathology