title: Variance in coronary venous anatomy: a critical determinant in optimal candidate selection for cardiac resynchronization therapy.
abstract: BACKGROUND
  Knowledge of coronary sinus (CS) anatomy and its variations is one of the important factors determining the final position of left ventricle pacing lead during cardiac resynchronization therapy.
  
  
  METHODS
  Coronary venous system anatomy, including number, diameter, and opening angles of tributaries, was studied in 50 normal formalin-fixed adult cadaveric hearts.
  
  
  RESULTS
  Thebesian valve (TV) and Vieussens valve were present in 64% and 60% cases, respectively. CS ostium coverage of ≥75% by TV was seen in 25% (8/32) cases. Number of prominent tributaries lying between anterior interventricular vein and middle cardiac vein varied from 1-4. In 28% of hearts, only one prominent tributary was present. Midlateral vein (average diameter 1.75 ± 0.66 mm) with an average distance of 43.5 ± 12.2 mm from coronary ostium was present in 58% (29/50) hearts, of which it formed an acute angle with CS axis in four (13.39%) cases. Posterolateral vein (average diameter 1.62 ± 0.45 mm) with an average distance of 33.4 ± 11.7 mm from coronary ostium was found in 72% (36/50) cases and formed an acute angle with CS in three (8.33%) cases.
  
  
  CONCLUSIONS
  Restrictive TV covering ≥75% CS ostium (25% cases), presence of single prominent tributary (28% cases), and formation of acute angle of tributary with CS axis (1/4 cases with anterolateral vein, 4/29 cases with midlateral vein, 3/36 cases with posterolateral vein, and 3/28 cases with posterior veins of the left ventricle) can impede successful cannulation of CS.
authors.affiliation: Department of Anatomy, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
authors.forename: Arpandeep
authors.initials: A
authors.lastname: Randhawa
authors.forename: Abhimanyu
authors.initials: A
authors.lastname: Saini
authors.forename: Anjali
authors.initials: A
authors.lastname: Aggarwal
authors.forename: Manoj K
authors.initials: MK
authors.lastname: Rohit
authors.forename: Daisy
authors.initials: D
authors.lastname: Sahni
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D058409:Cardiac Resynchronization Therapy Devices; D003330:Coronary Vessel Anomalies / Q000473:pathology*; D003331:Coronary Vessels / Q000473:pathology*; D004567:Electrodes, Implanted; D006801:Humans; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D019919:Prosthesis Implantation / Q000379:methods; D055815:Young Adult