Effect of Atrioventricular Conduction Prolongation on Optimization of Paced Atrioventricular Delay for Biventricular Pacing After Cardiac Surgery

• Published in: Journal of cardiothoracic and vascular anesthesia 2012-04, Vol.26 (2), p.209-216
• Main Authors: Rusanov, Alexander, MD, Wang, Daniel Y., MD, Cabreriza, Santos E., MBA, Bedrosian, Lauren N., BA, Karl, Suzanne R., BA, Richmond, Marc E., MD, Quinn, T. Alexander, PhD, Cheng, Bin, PhD, Spotnitz, Henry M., MD
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Anesthesia & Perioperative Care; atrioventricular delay; Atrioventricular Node - physiology; biventricular pacing; cardiac resynchronization therapy; Cardiac Resynchronization Therapy - methods; Cardiac Resynchronization Therapy - standards; Cardiac Surgical Procedures - adverse effects; Cardiopulmonary Bypass - adverse effects; Critical Care; electrophysiology; Female; Heart Conduction System - physiology; hemodynamics; Humans; Male; Middle Aged; perioperative management; Retrospective Studies; Time Factors; Treatment Outcome
• ISSN: 1053-0770; 1532-8422
• DOI: 10.1053/j.jvca.2011.07.030

Objectives Atrioventricular conduction prolongation (AVCP) in cardiac pacing is measurable and results primarily from delayed atrial conduction. Noninvasive methods for measuring atrial conduction are lacking. Accordingly, AVCP was used to estimate atrial conduction and investigate its role on the paced atrioventricular delay (pAVD) during biventricular pacing (BiVP) optimization. Design Retrospective analysis of data collected as part of a randomized controlled study of temporary BiVP after cardiopulmonary bypass. Setting Single-center study at university-affiliated tertiary care hospital. Participants Cardiac surgical patients at risk of left ventricular failure after cardiopulmonary bypass. Interventions Temporary BiVP was optimized immediately after cardiopulmonary bypass. Vasoactive medication and fluid infusion rates were held constant during optimization. Measurements and Main Results For each patient the AVCP and the pAVD producing the optimum (highest) cardiac output (OptCO) and mean arterial pressure (OptMAP) were determined. Patients were stratified into long- and short-AVCP groups. Overall AVCP (mean ± standard deviation) was 64 ± 28 ms. For the short-AVCP group (64 ms, n = 4), these same parameters were 89 ± 10, 218 ± 44, and 218 ± 29 ms. OptCO and OptMAP were significantly less in the short-AVCP group ( p = 0.015 and p = 0.029, respectively). Conclusions AVCP varies widely after cardiopulmonary bypass, affecting optimum pAVD. Failure to correct for this can result in the selection of inappropriately short and potentially deleterious pAVDs, especially when nominal pAVD is used, causing BiVP to appear ineffective.