title: Cardiac positioning using an apical suction device maintains beating heart hemodynamics.
abstract: BACKGROUND
  Cardiac positioning during off-pump coronary artery bypass (OPCAB) using deep pericardial sutures (DPS) typically results in some degree of hemodynamic compromise. We sought to determine whether cardiac positioning using an apical suction device was hemodynamically superior to DPS.
  
  
  METHODS
  Five healthy pigs underwent sternotomy and instrumentation to measure right atrial (RA) pressure, left ventricular (LV) pressure and volume, and aortic pressure and flow. These variables were recorded at baseline, with simple attachment of the apical suction device (Xpose Access Device, Guidant, Inc.), and during exposure of the posterior descending artery (PDA) and obtuse marginal (OM) branches of the left circumflex artery using DPS and the apical suction device.
  
  
  RESULTS
  Application of the apical suction device to the beating heart in neutral anatomic position did not result in any statistically significant change in hemodynamics compared to baseline except for a small decrease in RA pressure. DPS positioning resulted in statistically significant compromise in nearly all measured hemodynamic parameters, including cardiac output (-21% PDA, -30% OM), mean arterial pressure (-18% PDA, -26% OM), and stroke work (-31% PDA, -38% OM). In addition, LV end-diastolic pressure decreased (-59% PDA, -51% OM) while RA pressure increased (+17% PDA, +16% OM). Similar target exposure using the apical suction device resulted in near-baseline hemodynamics. The only statistically significant changes were a modest decrease in cardiac output (-18% OM) and RA pressure (-11% PDA).
  
  
  CONCLUSIONS
  DPS positioning significantly compromises hemodynamics due to reduced LV filling. The apical suction device provides good exposure with less hemodynamic compromise.
authors.affiliation: Division of Cardiac Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA. jsepic@partners.org
authors.forename: Jerome
authors.initials: J
authors.lastname: Sepic
authors.forename: Jon O
authors.initials: JO
authors.lastname: Wee
authors.forename: Edward G
authors.initials: EG
authors.lastname: Soltesz
authors.forename: Michael K
authors.initials: MK
authors.lastname: Hsin
authors.forename: Lawrence H
authors.initials: LH
authors.lastname: Cohn
authors.forename: Rita G
authors.initials: RG
authors.lastname: Laurence
authors.forename: Lishan
authors.initials: L
authors.lastname: Aklog
mesh_terms: D000818:Animals; D001026:Coronary Artery Bypass / Q000295:instrumentation; D006321:Heart / Q000502:physiology*; D006353:Heart-Assist Devices; D006439:Hemodynamics / Q000502:physiology*; D023421:Models, Animal; D008955:Models, Cardiovascular; D011187:Posture / Q000502:physiology*; D012016:Reference Values; D013396:Suction; D013536:Suture Techniques; D013552:Swine; D016277:Ventricular Function, Left / Q000502:physiology