Analysis of Ventricular Performance as a Function of Pacing Site and Mode

doi:10.1016/j.pcad.2008.01.001

Progress in Cardiovascular Diseases

Volume 51, Issue 2, September–October 2008, Pages 171-182

https://doi.org/10.1016/j.pcad.2008.01.001 Get rights and content

Emerging data from experimental and clinical studies have shown that right ventricular (RV) apical pacing led to abnormalities of ventricular activation and contraction, and impairment of myocardial perfusion with adverse left ventricular (LV) remodeling, which was associated with increased risk of cardiac morbidity and mortality. As a result, there is a growing interest in searching for methods to minimize unnecessary RV pacing and preserving normal ventricular activation with alternative ventricular pacing sites. The risk of developing heart failure (HF) after RV apical pacing depends on the interactions between patient-specific factors (baseline atrial rhythm, intrinsic atrioventricular and ventricular conduction, LV ejection fraction, and the presence of HF and myocardial infarction) and pacing-related factors (mode of pacing, site of ventricular pacing, paced QRS duration, and percentage and duration of pacing). In patients with intact atrioventricular conduction, atrial-based pacing should be used to avoid unnecessary ventricular pacing. In patients requiring ventricular pacing, the potential benefits of alternate ventricular pacing sites, such as RV or LV septa, or even biventricular pacing in different patient populations remain unclear and warrant further long-term prospective clinical trial evaluations especially in those patients who are at a higher risk of developing HF after RV apical pacing.

Section snippets

Normal Ventricular Activation and Contraction

Normal cardiac electrical impulses propagate from the AV node to the highly specialized His-Purkinje conduction system to coordinate the contraction of ventricular myocardium.

In general, the electrical activation wavefronts first exit to the LV endocardial cavity at the lower interventricular septum and then propagate in an apicobasal direction because the initial portion of the His-Purkinje system is electrically insulated from the surrounding contractile ventricular myocardium. As a result,

Adverse Hemodynamic Effects of Left Bundle Branch Block

The normal physiologic electrical activation of left ventricle can be disrupted in patients with structural heart diseases, such as dilated cardiomyopathy as manifested by the occurrence of intraventricular conduction defect with left bundle branch block (LBBB) and/or widening of QRS duration. During LBBB, the ventricular activation starts in the right ventricle, and the left ventricle is activated by a slow right-to-left transseptal conduction, which then propagates into the LV cavity at the

Impacts of Ventricular Pacing Modes and Sites on Development of HF

In patients with congenital³⁴ or acquired3, 4, 35 AV block, chronic RV apical pacing can lead to deterioration of LV systolic and diastolic function in up to 31% to 50% of patients. Although the prevalence of abnormal LV function and/or evidence of ventricular dyssynchrony are observed in up to two third of patients after permanent RV apical pacing,6, 35 the incidence of HF after ventricular pacing remains rather low. The risk of developing HF after RV apical pacing depends on the interactions

Optimal Choice of Pacing Mode and Pacing Site

In view of the potential harmful effects of RV apical pacing on LV function, different approaches to the selection of pacing mode and pacing site have been investigated to prevent or attenuate these effects.

Future Perspectives for Cardiac Pacing

The field of cardiac pacing has been changing to a paradigm with new definitions of physiologic ventricular pacing. Future clinical trials on cardiac pacing will be focused on the use of different pacing modes and/or pacing sites to maximize the benefits and minimize the harmful effects to LV function because of artificial cardiac stimulation. First, it is very clear that the normal ventricular conduction should be preserved by avoiding unnecessary RV apical pacing if possible. However, the

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Cited by (27)

Outcomes in patients with electrocardiographic left ventricular dyssynchrony following transcatheter aortic valve replacement
2023, Heart Rhythm
Citation Excerpt :
In the PACE (Pacing to Avoid Cardiac Enlargement) trial, high-burden RV pacing (>97%) resulted in the development of cardiomyopathy in 9% of patients.16 In addition, TAVR frequently is complicated by the development of new-onset left bundle branch block (LBBB), which is associated with adverse hemodynamic effects due to LV dyssynchrony.18 New persistent or permanent LBBB may impact LV function and has been associated with increased need for PPM implantation and higher mortality.19–23
Left bundle branch block (LBBB) and atrioventricular (AV) conduction abnormalities requiring permanent pacemaker (PPM) implantation occur frequently following transcatheter aortic valve replacement (TAVR). The resultant left ventricular (LV) dyssynchrony may be associated with adverse clinical events.
The purpose of this study was to assess the adverse outcomes associated with LV dyssynchrony due to high-burden right ventricular (RV) pacing or permanent LBBB following TAVR in patients with preserved left ventricular ejection fraction (LVEF).
Consecutive TAVR patients at the University of Michigan from January 2012 to June 2017 were included. Pre-existing cardiac implantable electronic device, previous LBBB, LVEF <50%, or follow-up period <1 year were excluded. The primary outcome was all-cause mortality. Secondary outcomes included cardiomyopathy (defined as LVEF ≤45%), a composite endpoint of cardiomyopathy or all-cause mortality, and the change in LVEF at 1-year follow-up.
A total of 362 patients were analyzed (mean age 77 years). LV dyssynchrony group (n = 91 [25.1%]) included 56 permanent LBBB patients, 12 permanent LBBB patients with PPM, and 23 non-LBBB patients with PPM and high-burden RV pacing. Remaining patients served as control (n = 271 [74.9%]). After adjusted analysis, LV dyssynchrony had significantly higher all-cause mortality (adjusted hazard ratio [HR] 2.16; 95% confidence interval [CI] 1.07–4.37) and cardiomyopathy (adjusted HR 14.80; 95% CI 6.31–14.69). The LV dyssynchrony group had mean LVEF decline of 10.5% ± 10.2% compared to a small increase (0.5% ± 7.7%) in control.
Among TAVR patients with preserved LVEF and normal AV conduction, development of postprocedural LV dyssynchrony secondary to high-burden RV pacing or permanent LBBB was associated with significantly higher risk of death and cardiomyopathy at 1-year follow-up.
The impact of paced QRS duration on the expression of genes related to contractile function of the left ventricle in chronically paced patients from the right ventricular apex
2020, Hellenic Journal of Cardiology
Citation Excerpt :
Patient-specific factors comprise the presence of intrinsic AV and ventricular conduction disturbances, baseline atrial rhythm, LV ejection fraction (EF), presence of heart failure (HF) and/or coronary artery disease (CAD) at the time of implantation. Pacing-related factors include the mode of pacing, site of ventricular lead, duration of paced QRS, percentage of ventricular pacing and duration of pacing.2,3 We hypothesized that duration of paced QRS could serve as an index of the assynchrony induced by RV apical pacing.
Right ventricular (RV) apex has proven to induce abnormal left ventricular (LV) activation pattern leading to pacing-induced cardiomyopathy (PICM) in a substantial percentage of paced patients. This study assessed the impact of paced QRS duration on the expression in the peripheral blood of sarcoplasmic reticulum calcium ATPase (SERCA) and investigated whether its width is related to the extend of LV remodelling.
We enrolled 52 consecutive patients with preserved ejection fraction (EF) who underwent pacemaker implantation for bradycardic indications. Group A consisted of 24 patients paced for atrioventricular conduction disturbances with QRS = 142 ± 12 ms post-implant and group B of 28 patients paced for sinus node disease with QRS = 94 ± 2%ms post-implant. mRNA levels of SERCA were assesed at implantation, 3, 6 and 12 months follow-up, while echocardiographic parameters at implantation, 1, 2 and 4 years.
In group A, mRNA levels of SERCA decreased significantly at 3 months and remained low at 6 and 12 months' follow-up and were associated to the deterioration of LV function and geometry. Paced QRS duration was associated to both the alteration in the expression of SERCA and to the extend of LV remodelling. In group B no statistically significant change was demonstrated.
Permanent RV pacing in patients with preserved EF and wide QRS post-implant is associated with a significant reduction of mRNA levels of SERCA. Paced QRS duration is associated to alterations in the expression of SERCA which precede adverse LV remodelling.
Adverse effects of left ventricular electrical dyssynchrony on cardiac reverse remodeling and prognosis after aortic valve surgery
2018, Journal of Cardiology
Citation Excerpt :
The hemodynamic and mechanical disadvantages of right ventricular (RV) apical pacing are similar to those of LBBB [6]. RV apical pacing induces dyssynchrony, which leads to increased sympathetic activation, causes abnormalities in myocardial perfusion, and worsened hemodynamic parameters and myocardial remodeling [6–8]. However, evidence for the clinical impact of ED after aortic valve surgery remains scarce.
Electrical dyssynchrony (ED) is one of the important contributing mechanisms in the progression of heart failure. We hypothesized that ED would interfere with cardiac reverse remodeling and affect prognosis after aortic valve surgery.
A total of 411 consecutive patients (233 males, mean age 65 ± 11 years) who underwent aortic valve surgery were retrospectively analyzed. The patients were divided into two groups according to the presence of ED [Group 1: no ED (n = 382, 93%), Group 2: ED (n = 29, 7%)]. ED was defined as either left ventricular bundle branch block, or electrical pacing rhythm. Cardiac reverse remodeling was assessed at 1 year after surgery by the changes in left ventricular ejection fraction (LVEF), LV end-systolic volume (LVESV), and left atrial volume index (LAVI). The primary endpoint was a composite of hospitalization for heart failure, and all-cause mortality.
At 1 year after surgery, group 2 showed lower LVEF (58 ± 15% vs. 64 ± 9%, p = 0.044), and higher LAVI (42 ± 18 ml/m² vs. 33 ± 13 ml/m², p = 0.018) than group 1. However, LVESV values (55 ± 38 ml vs. 42 ± 24 ml, p = 0.076) were not significantly different. In particular, in patients with reduced preoperative LVEF, the LVEF was markedly increased in group 1 but not in group 2 after 1 year. During a median follow-up of 39 months, group 2 showed a worse clinical outcome than group 1 (20.7% vs. 7.6%, p = 0.031). After adjusting for confounding factors in the multivariate analyses, age [hazard ratio (HR) 1.11, 95% confidence interval (CI) 1.06–1.16, p < 0.001] and the presence of ED (HR 2.43, 95% CI 1.01–5.89, p = 0.046) were found to be independent predictors of clinical outcomes.
ED after aortic valve surgery negatively affected cardiac remodeling and prognosis.
Effect of left ventricular pacing mode and site on hemodynamic, torsional and strain indices
2016, Hellenic Journal of Cardiology
Citation Excerpt :
Ventricular pacing at any site may have an adverse effect on pump function. However, among all LV pacing sites the LV apex generally results in the best maintenance of pump function, in non-ischemic animal hearts and when pacing is applied outside the necrotic region.2,7,12,23–28 Ventricular pacing at the apex or lateral wall suffers from the lack of the “atrial kick,” which produces a significant reduction in LV systolic pressure in the ischemic myocardium.
Several reports have indicated that left ventricular (LV) lead placement at an optimal pacing site is an important determinant of short- and long-term outcome. This study investigated the effect of pacing mode (atrioventricular [AV] or ventricular) and site (LV apical or lateral) outside the ischemic region on the LV hemodynamic, torsional and strain indices in the ischemic myocardium.
Experiments were conducted in anesthetized open-chest pigs (n = 15) 30 min after LAD ligation to investigate the hemodynamic effects of temporary epicardial AV and ventricular LV pacing at the LV apical (outside the ischemic region) or lateral wall. LV hemodynamic data were recorded (ejection fraction, stroke volume, dP/dt_max, systolic pressure, cardiac output and e/e΄ ratio) and torsional (twist, rotation), as well as deformation (radial and circumferential strain), indices of LV function were assessed using two-dimensional speckle tracking imaging.
The LV function was highly dependent on the pacing mode and site. LV dP/dt_max, systolic pressure and twist decreased significantly during LV pacing in comparison to sinus rhythm (p = 0.004, p<0.001, p = 0.002, respectively). Torsion in sinus rhythm decreased significantly during AV-pacing at the lateral wall (0.11 ± 0.04°/mm vs. 0.06 ± 0.02°/mm, p = 0.005) but did not change significantly during AV-pacing at the apex (0.07 ± 0.05°/mm).
LV pacing at the apical or lateral wall, in the ischemic myocardium, leads to a suboptimal response in comparison to sinus rhythm. LV pacing at the apex outside the ischemic area exhibits a better response than pacing at the lateral wall, possibly because pacing from this site leads to a more physiological propagation of electrical conduction.
Permanent septal pacing in patients suffering secondary heart failure compared to right ventricular apical pacing
2018, Archivos de Cardiologia de Mexico
Independientemente de la modalidad de estimulación (VVI o DDD), el mayor porcentaje de estimulación ventricular derecha deteriora la función contráctil izquierda. Por ello se han estudiado diferentes sitios de estimulación.
Describir las diferencias electrocardiográficas y ecocardiográficas entre la estimulación en la región apical y la región septal del ventrículo derecho (VD)0.
Se estudió a 24 pacientes, 2 mujeres y 22 hombres, con fracción de eyección deprimida (≤ 35%) secundaria a estimulación en punta de VD. Se realizó electrocardiograma durante estimulación en ápex de VD y en seguimiento de estimulación septal. También ecocardiografía en ambos momentos.
La fracción de eyección se incrementó desde 31 ± 3.1% hasta 45 ± 12% (p = 0.0041) con estimulación septal; esta mostró mejor grado de sincronía mecánica.
La estimulación septal puede constituir un sitio de elección en pacientes con disfunción sistólica de ventrículo izquierdo secundaria a estimulación en ápex de VD, los cuales presenten QRS estrecho en su conducción intrínseca, pues en la muestra estudiada produce una mejoría en la sincronía electromecánica, demostrándose incrementos significativos en la fracción de eyección.
Regardless of the type of electrical stimulation (VVI or DDD) the highest percentage of right ventricular apical pacing can cause left ventricular failure. For this reason, studies have been performed in different sites on right ventricle pacing.
To describe differences between electrocardiography and echocardiography variables during right ventricular apical pacing and septal pacing.
A total of 24 patients were studied, 2 women and 22 men, with heart failure due to conventional pacing on right ventricular (ejection fraction ≤ 35%). An electrocardiogram as well as an echocardiogram, was performed during right ventricular apical pacing and when patients were paced on septal area.
The ejection fraction increased from 31 ± 3.1% to 45 ± 12% (P=.0041) on septal pacing, showing higher degree of mechanic synchronisation.
Pacing on septal area could be a good site for those patients that suffer heart failure due to right ventricular apical pacing. These must show narrow QRS on their intrinsic electrocardiographic conduction. This kind of pacing can produce an improvement in electromechanical synchronisation, as well as show an increased left ventricular ejection fraction.
The relationship between right ventricular pacing voltage and QRS complex duration
2009, Physiological Measurement

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Special articleAnalysis of Ventricular Performance as a Function of Pacing Site and Mode

Section snippets

Normal Ventricular Activation and Contraction

Adverse Hemodynamic Effects of Left Bundle Branch Block

Impacts of Ventricular Pacing Modes and Sites on Development of HF

Optimal Choice of Pacing Mode and Pacing Site

Future Perspectives for Cardiac Pacing

J Am Coll Cardiol

J Am Coll Cardiol

J Am Coll Cardiol

Am J Cardiol

Lancet

J Am Coll Cardiol

J Am Soc Echocardiogr

J Electrocardiol

Am Heart J

J Am Coll Cardiol

J Am Coll Cardiol

J Am Coll Cardiol

J Am Coll Cardiol

J Am Coll Cardiol

J Am Coll Cardiol

Chest

Am Heart J

Am Heart J

J Am Coll Cardiol

J Am Coll Cardiol

J Am Coll Cardiol

J Am Coll Cardiol

Heart Rhythm

Heart Rhythm

J Electrocardiol

J Am Coll Cardiol

Lancet

Heart Rhythm

J Am Coll Cardiol

J Am Coll Cardiol

J Am Coll Cardiol

J Am Coll Cardiol

J Am Coll Cardiol

J Am Coll Cardiol

J Am Coll Cardiol.

J Am Coll Cardiol

An intracardiac pacemaker for Stokes-Adams seizures

N Engl J Med

The muscular reactions of the mammalian ventricles to artificial stimuli

Am J Physiol

The prevalence of heart failure and asymptomatic left ventricular systolic dysfunction in a typical regional pacemaker population

Eur Heart J

Heart failure and echocardiographic changes during long-term follow-up of patients with sick sinus syndrome randomized to single-chamber atrial or ventricular pacing

Circulation

Dual-chamber pacing or ventricular backup pacing in patients with an implantable defibrillator: the Dual Chamber and VVI Implantable Defibrillator (DAVID) Trial

JAMA

Adverse effect of ventricular pacing on heart failure and atrial fibrillation among patients with normal baseline QRS duration in a clinical trial of pacemaker therapy for sinus node dysfunction

Circulation

Cardiac resting and action potentials recorded with an intracellular electrode

J Physiol

Total excitation of the isolated human heart

Circulation

Endocardial mapping in humans in sinus rhythm with normal left ventricles: activation patterns and characteristics of electrograms

Circulation

Endocardial activation of left bundle branch block

Circulation

Left ventricular or biventricular pacing improves cardiac function at diminished energy cost in patients with dilated cardiomyopathy and left bundle-branch block

Circulation

Functional abnormalities in isolated left bundle branch block. The effect of interventricular asynchrony

Circulation

Additional predictive value of both left and right ventricular ejection fractions on long-term survival in idiopathic dilated cardiomyopathy

Eur Heart J

Prognostic significance of electrocardiographic findings in patients with dilated cardiomyopathy

Heart Vessels

Special article
Analysis of Ventricular Performance as a Function of Pacing Site and Mode