Temporary epicardial left ventricular and biventricular pacing improves cardiac output after cardiopulmonary bypass

Temporary Epicardial Pacing After Cardiac Surgery

Temporary epicardial pacing frequently is employed after cardiac surgery, and can have a significant impact on a patient's hemodynamics, arrhythmias, and valvulopathies. Given that anesthesiologists often are involved intimately in the initial programming and subsequent management of epicardial pacing in the operating room and intensive care unit, it is important for practitioners to have a detailed understanding of the modes, modifiable intervals, and potential complications that can occur after cardiac surgery. Because this topic has not been reviewed recently in anesthesia literature, the authors attempted to review relevant epicardial pacemaker specifics, discuss modes and parameters that apply to the perioperative period, present an algorithm for mode selection, describe the potential effects of epicardial pacing on valvulopathies and hemodynamics, and, finally, discuss some postoperative considerations.

Insertion and Management of Temporary Pacemakers

Temporary pacemakers are used in a variety of critical care settings. These life-saving devices are reviewed in 2 major categories in this review: first, the insertion and management of epicardial pacemakers after and during cardiac surgery; and second, the insertion of transvenous temporary pacemakers for the emergent treatment of bradyarrhythmias. Temporary epicardial pacemakers are used routinely in patients recovering from cardiac surgery. Borrowing from advances in cardiac resynchronization therapy there are many theoretical and untested benefits to pacing the postoperative cardiac surgery patient. Temporary transvenous pacing is traditionally an emergency procedure to stabilize patients suffering from hemodynamically unstable bradyarrhythmia. We review the traditional and expanding use of transvenous pacemakers inside and outside the operating room.

Feasibility of speckle-tracking echocardiography for assessment of left ventricular dysfunction after cardiopulmonary bypass

OBJECTIVES

Effects of temporary biventricular pacing after cardiopulmonary bypass are unpredictable, and the utility of speckle-tracking echocardiography in this setting is unclear. Accordingly, speckle-tracking analysis of transgastric echocardiograms taken during cardiac surgery was assessed as a potential tool to measure strain, synchrony, and twist as indices to predict response.

DESIGN

Prospective observational study, in part, with a randomized controlled study of temporary permanent biventricular pacing after cardiopulmonary bypass.

SETTING

Single-center study at university-affiliated tertiary care hospital.

PARTICIPANTS

Twenty-one cardiac surgery candidates with ejection fraction ≤40% and QRS duration ≥100 ms or who were undergoing double-valve surgery.

INTERVENTIONS

Transgastric views of the basal, midpapillary, and apical levels of the left ventricle were acquired before and after bypass.

MEASUREMENTS AND MAIN RESULTS

Midpapillary sections were analyzable in 38% of patients. The remainder had epicardial borders extending beyond the field of view (24%) or inadequate image quality (38%). Only 9% of basal or apical sections were analyzable. Midpapillary radial strain and synchrony changed insignificantly after bypass. Variation in fractional area change correlated with changes in radial strain (p = 0.041) but not with synchrony.

CONCLUSIONS

Intraoperative transgastric echocardiography is inadequate for speckle-tracking analysis with current techniques. Intraoperative predictors of temporary biventricular pacing response are lacking.

Temporary Endocavitary Pacemakers and their Use and Misuse: the Least is Better

Temporary pacemakers are classically indicated for severe bradydysrhythmia, especially when the clinical settings require prompt intervention. Implantation of a temporary pacemaker is not a benign procedure since it may be associated with serious adverse events such as infection, cardiac perforation, and lead dislodgment. Accordingly, we recommend, when the clinical condition allows, to proceed directly with permanent pacemaker implantation without prior use of a temporary pacemaker. However, if a temporary pacemaker is required, it should be maintained for the shortest time possible. This policy allows avoiding or decreasing the potential complications associated with temporary pacemaker implantation.