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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.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.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).DPS positioning significantly compromises hemodynamics due to reduced LV filling. The apical suction device provides good exposure with less hemodynamic compromise.

Background: Coronary artery hemostasis during off-pump coronary artery bypass (OPCAB) may be achieved with extraluminal coronary occlusion or intraluminal coronary shunting. We sought to determine with a normal porcine beating-heart model whether coronary shunting preserves regional myocardial perfusion and function compared with coronary occlusion. Methods: Six pigs (50-60 kg) underwent sternotomy and instrumentation. Two pairs of ultrasonic crystals were placed in the distribution of the left anterior descending (LAD) and left circumflex (LCx) arteries for measurement of fractional change in area (FCA), an index of regional contractility. Regional myocardial blood flow (RMBF) was determined with radiolabeled microspheres. Data were recorded for each animal at baseline and after LAD arteriotomy and vascular control with (1) a 1.5-mm intraluminal shunt, (2) proximal occlusion, and (3) proximal and distal occlusion. Results: One pig experienced ventricular fibrillation during LAD manipulation and was excluded from the study. Data were summarized for the remaining 5 animals. Coronary shunting maintained RMBF and function (FCA) compared with baseline. Proximal occlusion led to 50% (P = .05) and 47% (P = .04) decreases in RMBF and FCA, respectively, in the LAD region. Proximal and distal occlusion led to 55% (P = .03) and 51% (P = .02) decreases in RMBF and FCA, respectively, in the LAD region. There were no significant changes in RMBF or FCA in the LCx (control) region. Conclusion: Intraluminal coronary shunting is capable of preserving distal myocardial perfusion and function in a normal porcine heart. Coronary occlusion, in contrast, significantly reduces regional perfusion and function. More frequent use of intracoronary shunting may facilitate OPCAB by minimizing ischemia and hemodynamic compromise.