Four‐Chamber Pacing in Patients with Poor Ejection Fraction but Normal QRS Durations Undergoing Open Heart Surgery

Pichlmaier, Maximilian; Bagaev, Eric; Lichtenberg, A.; Teebken, Omke E.; Klein, Gunnar; Niehaus, Michael; Haverich, Axel

doi:10.1111/j.1540-8159.2007.00967.x

Cited by 9 publications

(3 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Intrinsic QRSd reportedly decreases over the same time period [23], and our unpublished data concur with this. Decreasing QRSd and BiVP effectiveness after bypass suggest that ischemia-reperfusion injury [38] is involved in post-surgical efficacy of BiVP, rather than conduction-related dyssynchrony [12,14,28].…”

Section: Commentsupporting

confidence: 86%

Primary Endpoints of the Biventricular Pacing After Cardiac Surgery Trial

Spotnitz¹,

Cabreriza²,

Wang³

et al. 2013

The Annals of Thoracic Surgery

View full text Add to dashboard Cite

Background To determine whether optimized biventricular pacing increases cardiac index in patients at risk of left ventricular dysfunction after cardiopulmonary bypass. Procedures included coronary artery bypass, aortic or mitral surgery and combinations. This trial was approved by the Columbia University Institutional Review Board and was conducted under an Investigational Device Exemption. Methods Screening of 6,346 patients yielded 47 endpoints. With informed consent, 61 patients were randomized to pacing or control groups. Atrioventricular and interventricular delays were optimized one (Phase I), two (Phase II), and 12–24 hours (Phase III) after bypass in all patients. Cardiac index was measured by thermal dilution in triplicate. Two-sample t-test assessed differences between groups and subgroups. Results Cardiac index was 12% higher (2.83±0.16 (S.E.M.) vs. 2.52±0.13 liters/minute/square meter) in the paced group, less than predicted and not statistically significant (p=0.14). However, when aortic and aortic/mitral surgery groups were combined, cardiac index increased 29% in the paced group (2.90±0.19, n=14) vs. controls (2.24±0.15, n=11) (p=0.0138). Using a linear mixed effects model, t-test revealed that mean arterial pressure increased with pacing vs. no pacing at all optimization points (Phase I 79.2±1.7 vs. 74.5±1.6 mmHg, p=0.008, Phase II 75.9±1.5 vs. 73.6±1.8, p=0.006, Phase III 81.9±2.8 vs. 79.5±2.7, p=0.002) Conclusions Cardiac index did not increase significantly overall but increased 29% after aortic valve surgery. Mean arterial pressure increased with pacing at three time points. Additional studies are needed to distinguish rate from resynchronization effects, emphasize atrioventricular delay optimization, and examine clinical benefits of temporary postoperative pacing.

show abstract

Section: Commentsupporting

confidence: 86%

Primary Endpoints of the Biventricular Pacing After Cardiac Surgery Trial

Spotnitz¹,

Cabreriza²,

Wang³

et al. 2013

The Annals of Thoracic Surgery

View full text Add to dashboard Cite

show abstract

“…Importantly, this is not associated with changes in myocardial energy demand (21), unlike most inotropic agents, which improve contractility at the expense of increased oxygen consumption and energy store depletion (29). Acute functional benefit without increased energy cost makes BiVP an excellent option for treatment of postoperative ventricular failure, and initial studies have shown its utility after cardiac surgery (14,20,23,24,33).…”

mentioning

confidence: 99%

Simultaneous variation of ventricular pacing site and timing with biventricular pacing in acute ventricular failure improves function by interventricular assist

Quinn

Cabreriza²,

Richmond

et al. 2009

American Journal of Physiology-Heart and Circulatory Physiology

View full text Add to dashboard Cite

The goal of this work was to investigate the hemodynamic effects of simultaneous left ventricular (LV) pacing site (LVPS) and interventricular pacing delay (VVD) variation with biventricular pacing (BiVP) during acute LV failure. Simultaneously varying LVPS and VVD with BiVP has been shown to improve hemodynamics during acute right ventricular (RV) failure. However, effects during acute LV failure have not been reported. In six open-chest pigs, acute LV volume overload was induced by regurgitant flow via an aortic-LV conduit. Epicardial BiVP was implemented with right atrial and ventricular leads and a custom LV pacing array. Fifty-four LVPS-VVD combinations were tested in random order. Cardiac output was evaluated by aortic flow probe, ventricular systolic function by maximum rate of ventricular pressure change, and mechanical interventricular synchrony by normalized RV-LV pressure diagram area. Simultaneous LVPS-VVD variation improved all measures of cardiac function. The observed effect was different for each functional index, with evidence of LVPS-VVD interaction. Compared with effects of LVPS-VVD variation in a model of acute RV failure, hemodynamic changes were markedly different. However, in both models, maximum rate of ventricular pressure change of the failing ventricle was improved with synchronous interventricular contraction, suggesting that, in acute ventricular failure, BiVP can recruit the unstressed ventricle to support systolic function of the failing one. Thus simultaneously varying LVPS and VVD with BiVP during acute ventricular failure can improve cardiac function by "interventricular assist", with hemodynamic effects dependent on the type of failure. This supports the potential utility of temporary BiVP for the treatment of acute ventricular failure commonly seen after cardiac surgery.

show abstract

“…Preliminary results from clinical trials have indicated that BiVP improves hemodynamics in this patient population. 9–11,13,14,17 Interim analyses of data from the BiPACS trial have highlighted the importance of perioperative optimization of pacing parameters. Of the pacing parameters studied, optimization of the pAVD was found to yield the greatest hemodynamic benefits.…”

Section: Discussionmentioning

confidence: 99%

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

Rusanov

Wang

Cabreriza

et al. 2012

Journal of Cardiothoracic and Vascular Anesthesia

View full text Add to dashboard Cite

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 = 3), AVCP, OptCO, and OptMAP were 40 ± 11, 120 ± 0, and 150 ± 30 ms, respectively, and for the long-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.

show abstract

Four‐Chamber Pacing in Patients with Poor Ejection Fraction but Normal QRS Durations Undergoing Open Heart Surgery

Cited by 9 publications

References 25 publications

Primary Endpoints of the Biventricular Pacing After Cardiac Surgery Trial

Primary Endpoints of the Biventricular Pacing After Cardiac Surgery Trial

Simultaneous variation of ventricular pacing site and timing with biventricular pacing in acute ventricular failure improves function by interventricular assist

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

Contact Info

Product

Resources

About