Buchanan D, Clements F, Reves JG, Hochman H, Kates R. Duke Univ Medical Center. Anesthesiology 69:595-598, 1988. Correlates of transesophageal atrial pacing thresholds and hemodynamic during TAP were measured in 21 patients during CABG surgery (11 patients during their first and 10 patients for the second surgery). Patient weight, body surface area, heart rate, cardiac index, systemic and pulmonary blood pressures and system vascular resistance were measured. Results: No significant differences in pacing threshold were found between the 2 patient groups (initial vs. second CABG) or between patient who had suffered a previous myocardial infarction and those who had not. Pacing threshold (mA) was positively correlated with body surface area, with an (approximated) linear regression equation of Threshold = -22 + 22 BSA. Eleven of 21 patients became bradycardic after tracheal intubation; their hemodynamic measurements before and during pacing were: