title: Effects of right, left, and biventricular pacing on myocardial perfusion in ischemic conditions.
abstract: OBJECTIVE
  In normal hearts, the distribution of regional myocardial perfusion is altered by ventricular pacing. Little is known about the impact of ventricular pacing on regional myocardial perfusion in ischemic conditions. In this acute echocardiographic study, we compared the respective effects of right ventricular pacing (RVP), left ventricular pacing (LVP), and biventricular pacing (BVP) on regional perfusion in a swine model of graded ischemia.
  
  
  RESULTS
  Ventricular pacing leads were placed at the apex of the right ventricle and on the lateral wall of the left ventricle in nine open-chest pigs. Myocardial contrast echocardiography was successively performed during spontaneous rhythm (SR), RVP, LVP, and BVP in random order at baseline and during three stages of incremental ischemia (left anterior descending + circumflex). At baseline, RVP decreased myocardial perfusion of the septal and inferior walls compared to SR (P < 0.05), whereas LVP decreased perfusion of the lateral wall (P < 0.05). No significant differences were observed in regional perfusion during BVP compared to SR. In ischemic conditions, RVP worsened myocardial perfusion in the ischemic anterior wall as well as in the septal and inferior walls (P < 0.05), whereas both LVP and BVP did not alter perfusion in the ischemic area compared to SR.
  
  
  CONCLUSIONS
  Compared to baseline, in ischemic conditions, RVP has a more pronounced detrimental impact on perfusion abnormalities. In contrast, BVP induced a significant improvement in local myocardial perfusion. Therefore, BVP could be preferred to RVP in patients with ischemic cardiomyopathy.
authors.affiliation: Inserm U. 441, Pessac, France. stephane.lafitte@chu-bordeaux.fr
authors.forename: Stephane
authors.initials: S
authors.lastname: Lafitte
authors.forename: Patricia
authors.initials: P
authors.lastname: Reant
authors.forename: Louis
authors.initials: L
authors.lastname: Labrousse
authors.forename: Pierre
authors.initials: P
authors.lastname: Bordachar
authors.forename: Liliane
authors.initials: L
authors.lastname: Tariosse
authors.forename: Bertrand
authors.initials: B
authors.lastname: Beauvoit
authors.forename: Karim
authors.initials: K
authors.lastname: Serri
authors.forename: Simone
authors.initials: S
authors.lastname: Bonoron-Adèle
authors.forename: Raymond
authors.initials: R
authors.lastname: Roudaut
authors.forename: Pierre
authors.initials: P
authors.lastname: Dos Santos
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D003326:Coronary Circulation; D006352:Heart Ventricles / Q000503:physiopathology*; D008297:Male; D017202:Myocardial Ischemia / Q000503:physiopathology* / Q000628:therapy*; D013552:Swine; D016896:Treatment Outcome