title: Determinants of preformed collateral vessels in the human heart without coronary artery disease.
abstract: BACKGROUND
  Coronary collaterals protect myocardium jeopardized by coronary artery disease (CAD). Promotion of collateral circulation is desirable before myocardial damage occurs. Therefore, determinants of collateral preformation in patients without CAD should be elucidated.
  
  
  METHODS
  In 106 patients undergoing coronary angiography who were free of coronary stenoses, a total of 39 clinical test variables were collected. The coronary collateral flow index (CFI) was measured. Stepwise multiple linear regression analysis was performed after choosing a restricted number of candidates emerging from univariate testing. Separate multiple regression analyses were performed in patients with and without beta-blocker therapy.
  
  
  RESULTS
  Nine parameters were found to be possible determinants of CFI by univariate analysis: arterial hypertension (aHT), dyslipidemia, statins, diuretics, age, height, heart rate (HR), pulse pressure amplitude, and left ventricular end-diastolic pressure (LVEDP). After multiple regression analysis, a low HR, absence of aHT, and elevated LVEDP were significantly related to CFI (F = 5.31, p = 0.002, adjusted r(2) = 0.12). In patients without beta-blockers, a low HR and absence of aHT were independent predictors of CFI (F = 8.03, p < 0.001, n = 50, adjusted r(2) = 0.30).
  
  
  CONCLUSIONS
  A low HR and absence of aHT are both related to collateral preformation in humans. We suppose that bradycardia favors fluid shear stress in coronary arteries, thus triggering collateral growth.
authors.affiliation: Department of Cardiology, University Hospital, Bern, Switzerland.
authors.forename: Stefano F
authors.initials: SF
authors.lastname: de Marchi
authors.forename: Steffen
authors.initials: S
authors.lastname: Gloekler
authors.forename: Pascal
authors.initials: P
authors.lastname: Meier
authors.forename: Tobias
authors.initials: T
authors.lastname: Traupe
authors.forename: Hélène
authors.initials: H
authors.lastname: Steck
authors.forename: Stéphane
authors.initials: S
authors.lastname: Cook
authors.forename: Rolf
authors.initials: R
authors.lastname: Vogel
authors.forename: Christian
authors.initials: C
authors.lastname: Seiler
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003097:Collateral Circulation / Q000502:physiology*; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D003326:Coronary Circulation / Q000502:physiology*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D017725:Ventricular Pressure / Q000502:physiology; D055815:Young Adult