title: New approach to intracardiac hemodynamic measurements in small animals: echo-guided percutaneous apical puncture.
abstract: OBJECTIVE
  Invasive measurements of intracardiac hemodynamics in animal models have allowed important advances in the understanding of cardiac disease. Currently they are performed either through a carotid arteriotomy or via a thoracotomy and apical insertion. Both of these techniques have disadvantages and are not conducive to repeated measurements. Therefore, the purpose of this study was to develop a new technique for measuring intracardiac hemodynamics.
  
  
  METHODS
  In 13 male rats, hemodynamic measurements were performed using a new echocardiographically guided percutaneous apical technique. An intravenous catheter was percutaneously inserted into the left ventricle (LV) in the direction of the LV long axis. Through this catheter, a micromanometer-tipped pressure catheter was inserted, and invasive hemodynamic traces were recorded. After LV recordings, the pressure catheter was advanced into the aorta where pressures were obtained. In 11 rats, measurements were repeated after 1 week (n = 2), 2 weeks (n = 4), 3 weeks (n = 4), or 4 weeks (n = 1). In 3 rats, invasive measurements were performed using a carotid arteriotomy before the percutaneous technique.
  
  
  RESULTS
  Among the 13 rats subjected to the procedure, the survival rate was 85%. Of the 11 rats that had the procedure repeated, 3 died (27%). The mean differences ± SD when comparing the two techniques were 10 ± 4 mm Hg for the LV end-systolic pressure and 1 ± 1 mm Hg for the LV end-diastolic pressure. The mean procedure times were 21 ± 3 and 6 ± 1 minutes for the carotid and percutaneous techniques, respectively.
  
  
  CONCLUSIONS
  We have successfully developed a percutaneous technique for insertion of LV microtip catheters in rats.
authors: Division of Cardiology, Johns Hopkins Medical Institutions, Baltimore, Maryland 21287, USA.
authors: Kristian
authors: K
authors: Eskesen
authors: Niels T
authors: NT
authors: Olsen
authors: Veronica L
authors: VL
authors: Dimaano
authors: Aurelio
authors: A
authors: Pinheiro
authors: Peter
authors: P
authors: Sogaard
authors: Thomas
authors: T
authors: Fritz-Hansen
authors: Lars L
authors: LL
authors: Sorensen
authors: Theodore P
authors: TP
authors: Abraham
mesh_terms: D000818:Animals; D006328:Cardiac Catheterization / Q000379:methods*; D004452:Echocardiography / Q000379:methods*; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000601:surgery*; D006439:Hemodynamics / Q000502:physiology*; D008297:Male; D008365:Manometry / Q000295:instrumentation; D011677:Punctures; D051381:Rats; D017207:Rats, Sprague-Dawley