The effect of single chamber pacing on ejection fraction, QRS morphology and QRS duration

Background: Left bundle branch area pacing (LBBAP) has recently been introduced as a novel physiological pacing strategy. Within LBBAP, distinction is made between left bundle branch pacing (LBBP) and left ventricular septal pacing (LVSP, no left bundle capture). Objective: To investigate acute electrophysiological effects of LBBP and LVSP as compared to intrinsic ventricular conduction. Methods: Fifty patients with normal cardiac function and pacemaker indication for bradycardia underwent LBBAP. Electrocardiography (ECG) characteristics were evaluated during pacing at various depths within the septum: starting at the right ventricular (RV) side of the septum: the last position with QS morphology, the first position with r’ morphology, LVSP and—in patients where left bundle branch (LBB) capture was achieved—LBBP. From the ECG’s QRS duration and QRS morphology in lead V1, the stimulus- left ventricular activation time left ventricular activation time (LVAT) interval were measured. After conversion of the ECG into vectorcardiogram (VCG) (Kors conversion matrix), QRS area and QRS vector in transverse plane (Azimuth) were determined. Results: QRS area significantly decreased from 82 ± 29 µVs during RV septal pacing (RVSP) to 46 ± 12 µVs during LVSP. In the subgroup where LBB capture was achieved (n = 31), QRS area significantly decreased from 46 ± 17 µVs during LVSP to 38 ± 15 µVs during LBBP, while LVAT was not significantly different between LVSP and LBBP. In patients with normal ventricular activation and narrow QRS, QRS area during LBBP was not significantly different from that during intrinsic activation (37 ± 16 vs. 35 ± 19 µVs, respectively). The Azimuth significantly changed from RVSP (−46 ± 33°) to LVSP (19 ± 16°) and LBBP (−22 ± 14°). The Azimuth during both LVSP and LBBP were not significantly different from normal ventricular activation. QRS area and LVAT correlated moderately (Spearman’s R = 0.58). Conclusions: ECG and VCG indices demonstrate that both LVSP and LBBP improve ventricular dyssynchrony considerably as compared to RVSP, to values close to normal ventricular activation. LBBP seems to result in a small, but significant, improvement in ventricular synchrony as compared to LVSP.

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Cathodic-anodal left ventricular stimulation during cardiac resynchronization therapy: haemodynamic evaluation and electrocardiographic analysis

European Heart Journal ◽

10.1093/ehjci/ehaa946.0799 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

M Gravellone ◽

G Dell' Era ◽

F De Vecchi ◽

E Boggio ◽

E Prenna ◽

...

Keyword(s):

Ejection Fraction ◽

Arterial Pressure ◽

Cardiac Resynchronization Therapy ◽

Right Ventricle ◽

Single Point ◽

Left Ventricular ◽

Cardiac Resynchronization ◽

Resynchronization Therapy ◽

Biventricular Stimulation ◽

Qrs Duration

Abstract Background Cardiac resynchronization therapy (CRT) is an established treatment for heart failure with reduced ejection fraction (HFrEF). However, one third of patients are “non responders”. Cathodic-anodal (CA) left ventricle (LV) capture is a multisite pacing occurring during CRT using both bipolar and quadripolar LV lead. It allows depolarization to arise simultaneously from the cathode and the anode of the bipole located on the LV epicardium, activating a larger volume of myocardium than cathodal pacing alone, thus potentially improving electromechanical synchrony (figure 1). We have previously proven that CA-LV stimulation is feasible and similar to bicathodic multipoint pacing (MPP) in terms of QRS wavefront activation. Purpose We aimed to evaluate both the acute intraprocedural haemodynamic and electrical effects of CA biventricular stimulation (CA-BS), comparing it with right-ventricle only pacing (Right Ventricle-Stimulation: RV-S), single-point CRT (Single Point-Biventricular Stimulation: SP-BS) and multipoint bicathodic biventricular stimulation (Multi Point-Biventricular Stimulation:MP-BS) in de novo CRT implants. Methods Ten patients candidates to CRT (LV ejection fraction ≤35% and left bundle branch block) received a quadripolar LV lead. Four pacing configurations were tested: RV-S, SP-BS, MP-BS and CA-BS, where cathode and the anode were the same electrodes used as cathodes in MP-BS. QRS duration by 12-lead ECG was defined as the time from the earliest ventricular deflection until the return to the isoelectric line. Haemodynamic assessment by radial artery catheterization using Pressure Recording Analytical Method processed the following parameters: dP/dT max (mmHg/msec), systolic arterial pressure (aPsys, mmHg), diastolic arterial pressure (aPdia, mmHg), mean arterial pressure (aPmean, mmHg), Cardiac Index (CI, l/min/m2), Stroke Volume Index (SVI, ml/min/m2). Results dP/dT max and aPmean increased significantly from RV-S to SP-BS (mean dP/dT max 0,82±0,28 versus 0,87±0,29 mmHg/msec, p=0,02; mean aPmean 89±19 versus 93±20 mmHg, p=0,01), but not from RV-S to MP-BS. Comparing RV-S to CA-BS, only aPmean exhibited a significant increase (mean aPmean 89±19 versus 92±20 mmHg, p=0,01). There were no haemodynamic differences between SP-BS, MP-BS and CA-BS. QRS duration reduced significantly from RV-S (167±10 msec) to each biventricular stimulation (135±14 msec, p=0,0002 for SP-BS; 130±17 msec, p=0,0001 for MP-BS; 129±18 msec, p=0,0002 for CA-BS) and from SP-BS to MP-BS and CA-BS (p=0,03 for both), whereas there were no difference comparing MP-BS and CA-BS. Conclusions CA-LV stimulation is not superior to single-point CRT in terms of acute haemodynamic performance, whereas it reduces the duration of ventricular electrical activation, showing an electrohaemodynamic mismatch. Long-term studies are needed to evaluate if acute electrical benefits of CA stimulation can predict chronic benefits, in terms of reverse cardiac remodelling. Cathodic-anodal left ventricular capture Funding Acknowledgement Type of funding source: None

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Automatic QRS morphology template update leads to inappropriate therapy inhibition in a single-chamber ICD

Heart Rhythm ◽

10.1016/j.hrthm.2005.02.922 ◽

2005 ◽

Vol 2 (5) ◽

pp. S293 ◽

Cited By ~ 1

Author(s):

Heather M. Ross ◽

Edward P. Gerstenfeld ◽

Henry H. Hsia ◽

Dusan Z. Kocovic

Keyword(s):

Inappropriate Therapy ◽

Single Chamber ◽

Template Update ◽

Qrs Morphology

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Abstract 13286: Non-Specific Intraventricular Conduction Delay and Risk of Sudden Death

Circulation ◽

10.1161/circ.130.suppl_2.13286 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Audrey Uy-Evanado ◽

Carmen Teodorescu ◽

Kyndaron Reinier ◽

Kumar Narayanan ◽

Harpriya Chugh ◽

...

Keyword(s):

Sudden Cardiac Death ◽

General Population ◽

Left Bundle Branch Block ◽

Cardiac Death ◽

Conduction Delay ◽

Bundle Branch Block ◽

Intraventricular Conduction ◽

Qrs Morphology ◽

Qrs Duration ◽

Intraventricular Conduction Delay

Introduction: We and others have reported an independent association between prolonged QRS duration and risk of sudden cardiac death (SCD) in the general population. Left and right bundle branch block have been studied previously, but there is little information regarding non-specific intraventricular conduction delay and risk of SCD. Hypothesis: Completed conduction defects, including non-specific IVCD, are associated with increased SCD risk. Methods: Sudden cardiac death cases and controls from an ongoing large population based study in the Northwestern US (2002 to 2010) were included if age ≥ 35 years with a non-paced 12-lead ECG (recorded prior and unrelated to SCD in cases). QRS morphology was subcategorized as normal, intermediate [left anterior fascicular block (LAFB), left posterior fascicular block (LPFB), and incomplete right or left bundle branch block (IRBBB/ILBBB)] or completed conduction defects [left bundle branch block (LBBB), right bundle branch block (RBBB), or nonspecific intraventricular conduction delay (IVCD)]. Comparisons were conducted using chi-square tests for categorical variables and independent samples t-tests for continuous variables. Logistic regression was used to evaluate the association of QRS morphology with SCD. Results: We evaluated 761 SCD cases (64% male) and 539 controls (65% male). Cases were significantly older (69.7 vs 66.3 years, p<0.0001) with greater QRS duration (102 vs. 98 ms, p=0.001). For conduction categories, intermediate or completed conduction defects were significantly more common in cases whereas normal QRS morphology was more common among controls (p=0.01). And for specific morphology overall, QRS morphology patterns differed between cases and controls (p=0.03); abnormal QRS morphologies were more frequent in cases than controls except for LAFB. After adjustment for age and gender, however, only a finding of LBBB or non-specific IVCD remained a significant predictor of SCD [OR 1.34 (95% CI 1.03-1.75)]. Conclusions: LBBB and non-specific IVCD, but not RBBB, are significant predictors of SCD in the general population. These findings contribute to the utility of the 12-lead EKG for SCD risk stratification.

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207: Electrocardiogram QRS Duration Predicts Recovery of Left Ventricular Ejection Fraction after Renal Transplant

The Journal of Heart and Lung Transplantation ◽

10.1016/j.healun.2009.11.218 ◽

2010 ◽

Vol 29 (2) ◽

pp. S72-S72

Author(s):

P.S.D. Yeo ◽

R. Fatica ◽

W.W.H. Tang

Keyword(s):

Left Ventricular Ejection Fraction ◽

Renal Transplant ◽

Ejection Fraction ◽

Left Ventricular ◽

Ventricular Ejection ◽

Left Ventricular Ejection ◽

Ventricular Ejection Fraction ◽

Qrs Duration

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Left Bundle Branch Area Pacing guided by Continuous Uninterrupted Monitoring of the unipolar Pacing Characteristics.

10.22541/au.162666894.40232490/v1 ◽

2021 ◽

Author(s):

Kris Gillis ◽

Jean-Yves Wielandts ◽

Gabriela Hilfiker ◽

Louisa O'Neill ◽

Alina Vlase ◽

...

Keyword(s):

Real Time ◽

Group Performance ◽

Accurate Determination ◽

Septal Perforation ◽

Validation Group ◽

Pacing Lead ◽

Qrs Morphology ◽

Qrs Duration ◽

Highly Correlated

Introduction. During left bundle branch area pacing (LBBAP) lead implantation, intermittent monitoring of unipolar pacing characteristics validates LBB capture and can detect septal perforation. We aimed to demonstrate that continuous uninterrupted unipolar pacing from an inserted lead stylet (LS) is feasible and facilitates LBBAP implantation. Methods. Thirty patients (mean age 76 ± 14 years) were implanted with stylet-driven pacing lead (Biotronik Solia S60). In 10 patients (validation-group) conventional, interrupted implantation was performed, with comparison of unipolar pacing characteristics between LS and connector-pin (CP)-pacing after each rotation step. In 20 patients (feasibility-group) performance and safety of uninterrupted implantation during continuous pacing from the LS were analyzed. Results. In the validation-group, LS and CP-pacing impedances were highly correlated (R=0.95, p<0.0001, bias 12±37Ω). Pacing characteristics from LS and CP showed comparable sensed electrograms and paced QRS morphologies. In the feasibility-group, continuous LS-pacing allowed beat-to-beat monitoring of impedance and QRS morphology to guide implantation. This resulted in successful LBBAP in all patients, after a mean of 1±0 attempts, with mean threshold 0.81 ± 0.4V, median sensing 6.5mV [IQR 4.4-9.5] and mean impedance 624 ± 101Ω, and positive LBBAP-criteria with median paced QRS duration 120ms [IQR 112-152ms] and median pLVAT 73ms [IQR 68-80.5ms]. No septal perforation occurred. Conclusion. Unipolar pacing from the LS allows accurate determination of pacing impedance and generates similar paced QRS morphologies and equal sensed electrograms, compared to CP pacing. Continuous LS pacing allows real-time monitoring of impedance and paced QRS morphology, which facilitates a safe and successful LBBAP lead implantation.

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Bi-Ventricular Pacing Upgrade Dramatically Increases Ejection Fraction and Functional Status Despite no Significant Decrease in Qrs Duration

Heart Lung and Circulation ◽

10.1016/j.hlc.2016.06.296 ◽

2016 ◽

Vol 25 ◽

pp. S124-S125

Author(s):

K. Dedini ◽

K. Phillips ◽

D. Arumugam ◽

A. Rehmani ◽

S. Pavia ◽

...

Keyword(s):

Ejection Fraction ◽

Functional Status ◽

Ventricular Pacing ◽

Qrs Duration

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Abstract 11159: Prolonged QRS Duration Predicts Outcomes in Heart Failure With Preserved Ejection Fraction

Circulation ◽

10.1161/circ.132.suppl_3.11159 ◽

2015 ◽

Vol 132 (suppl_3) ◽

Author(s):

Jacob Joseph ◽

Brian L Claggett ◽

Inder S Anand ◽

Jerome L Fleg ◽

Thao Huynh ◽

...

Keyword(s):

Heart Failure ◽

Ejection Fraction ◽

Primary Outcome ◽

Statistical Significance ◽

Study Cohort ◽

Preserved Ejection Fraction ◽

Entire Study ◽

Increased Risk ◽

Qrs Duration ◽

Entire Study Cohort

Introduction: QRS widening on the surface electrocardiogram (ECG) is a marker of disease progression in heart failure (HF) with reduced ejection fraction. We hypothesized that prolonged QRS duration would similarly identify patients with HF with preserved ejection fraction (HFPEF) at high risk for cardiovascular (CV) events. Methods: We examined the relationship of baseline QRS duration to primary outcome [composite of CV death, aborted cardiac arrest, or HF hospitalization (HFH)] and HFH alone in TOPCAT, a multicenter, randomized, placebo-controlled trial of spironolactone in HFPEF. QRS duration was analyzed as a dichotomous variable (≥ 120 ms or < 120 ms). Multivariable analyses were conducted including variables that were significantly associated with QRS duration ≥ 120 ms (Table 1). Analyses were conducted in the entire study cohort as well as in separate analyses for only subjects enrolled from the Americas or from Russia/Georgia independently. Results: QRS duration was known in 3426 of 3445 TOPCAT patients. Compared to those with QRS duration < 120ms, 613 (17.9%) subjects had a QRS duration ≥ 120 ms and were older (72.9 years vs. 67.8 years; p < 0.0001) and more likely to be men (62% vs. 45%; p<0.0001). A QRS duration ≥ 120 ms was independently associated with an increased risk of primary outcome and HFH in the entire study cohort and in the subset of patients enrolled in the Americas but was of borderline statistical significance in Russia/Georgia (Table 1). No statistical interaction was observed between treatment with spironolactone and QRS duration (p value for interaction= 0.33). Conclusions: QRS duration identifies HFPEF subjects at a higher risk of adverse clinical outcomes; spironolactone had a similar effect on outcomes independent of QRS duration. This easily obtainable marker may be an important component of risk stratification in this syndrome.

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