title: Validation of a new noninvasive device for the monitoring of peak endocardial acceleration in pigs: implications for optimization of pacing site and configuration.
abstract: BACKGROUND
  The peak of endocardial acceleration (PEA) is an index of myocardial contractility. We aimed to (1) demonstrate that the PEA measured by the noninvasive cutaneous precordial application of an accelerometer sensor is related to left ventricular (LV) dP/dt max and (2) assess the usefulness of PEA monitoring during graded ischemia and during different configurations of sequential biventricular pacing.
  
  
  RESULTS
  Measurements of invasive LV dP/dt max were compared with measurements of transcutaneous PEA in seven pigs at baseline and during acute drug infusions; increased heart rate; right, left, biventricular and sequential biventricular pacing before and after graded ischemia induced by the constriction of the left anterior descending coronary artery. A consistent PEA signal was obtained in all animals. PEA changes were highly related to LV dP/dt max changes (r= 0.93; P < 0.001). The changes of LV contractility induced by the different pacing configurations were detected by PEA analysis in the absence of ischemia (r= 0.94; P < 0.001) and in the presence of ischemic LV dysfunction (r= 0.91; P < 0.001).
  
  
  CONCLUSIONS
  Noninvasive PEA measurement allows monitoring of left ventricular contractility and may be a useful tool to detect global effect of ventricular ischemia and to optimize the choice of both pacing site and pacing configuration.
authors.affiliation: INSERM U 828, University Bordeaux 2, France. bordacharp@hotmail.com
authors.forename: Pierre
authors.initials: P
authors.lastname: Bordachar
authors.forename: Louis
authors.initials: L
authors.lastname: Labrousse
authors.forename: Sylvain
authors.initials: S
authors.lastname: Ploux
authors.forename: Jean-Benoit
authors.initials: JB
authors.lastname: Thambo
authors.forename: Stephane
authors.initials: S
authors.lastname: Lafitte
authors.forename: Patricia
authors.initials: P
authors.lastname: Reant
authors.forename: Pierre
authors.initials: P
authors.lastname: Jais
authors.forename: Michel
authors.initials: M
authors.lastname: Haissaguerre
authors.forename: Jacques
authors.initials: J
authors.lastname: Clementy
authors.forename: Pierre
authors.initials: P
authors.lastname: Dos Santos
mesh_terms: D000054:Acceleration; D000818:Animals; D002304:Cardiac Pacing, Artificial / Q000379:methods; D004699:Endocardium / Q000502:physiology*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008297:Male; D009200:Myocardial Contraction / Q000502:physiology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013552:Swine; D014159:Transducers; D016277:Ventricular Function, Left / Q000502:physiology*