Single-chamber ventricular pacing increases markers of left ventricular dysfunction compared with dual-chamber pacing

Cardiomyopathy Associated with Right Ventricular Apical Pacing-Systematic Review and Meta-Analysis

AIMS

Bradyarrhythmias are potentially life-threatening medical conditions. The most widespread treatment for slow rhythms is artificial ventricular pacing. From the inception of the idea of artificial pacing, ventricular leads were located in the apex of the right ventricle. Right ventricular apical pacing (RVAP) was thought to have a deteriorating effect on left ventricular systolic function. The aim of this study was to systematically assess results of randomized controlled trials to determine the effects of right ventricular apical pacing on left ventricular ejection fraction (LVEF).

METHODS

we systematically searched the Cochrane Central Register of Controlled Trials, PubMed, and EMBASE databases for studies evaluating the influence of RVAP on LVEF. Pooled mean difference (MD) with a 95% confidence interval (CI) was estimated using a random effect model.

RESULTS

14 randomized controlled trials (RCTs) comprising 885 patients were included. In our meta-analysis, RVAP was associated with statistically significant left ventricular systolic function impairment as measured by LVEF. The mean difference between LVEF at baseline and after intervention amounted to 3.35% (95% CI: 1.80-4.91).

CONCLUSION

our meta-analysis confirms that right ventricular apical pacing is associated with progressive deterioration of left ventricular systolic function.

Impacto dos Modos de Estimulação DDD e VVIR na Capacidade Funcional e Qualidade de Vida de Pacientes Chagásicos

Introdução: A estimulação atrioventricular propicia benefícios hemodinâmicos em relação à ventricular isolada, mas essa vantagem não está completamente estabelecida em pacientes chagásicos com disfunção sistólica. Objetivo:Avaliar a infl uência dos modos de estimulação DDD e VVIR na capacidade funcional, qualidade de vida (QV) e alterações laboratoriais de peptídeo natriurético em pacientes chagásicos com disfunção ventricular submetidos a implante de marcapasso. Métodos: Estudaram-se prospectivamente 20 pacientes (55% do sexo masculino) com média de idade de 62,7(± 9,9 anos) e média da fração de ejeção de 41,8% (± 2,8). Alternadamente, os pacientes receberam a estimulação nos modos DDD e VVIR por um período de três meses sob cada programação. O mínimo percentual de estimulação ventricular admitido foi de 80%. Após cada período, o paciente foi submetido ao teste de caminhada de seis minutos (TC6M), avaliação de QV pelo Minnesota Living with Heart Failure Questionnaire (MLHFQ) e pelo Assesment of QUAlity of life and RELated events (AQUAREL). A avaliação laboratorial foi realizada com a dosagem da fração N-terminal do peptídeo natriurético cerebral (N-terminal pro b-type natriuretic peptide – NT-proBNP). Resultados: A média da distância percorrida no TC6M nos modos DDD e VVIR foram respectivamente 390,60 (± 52,71) e 396,30 (± 52,71) metros (p = 0,160). Verifi caram-se resultados de QV inferiores, considerando o domínio físico do MLHFQ (p = 0,03) e os domínios dispneia de esforço(p = 0,05) e arritmia (p < 0,001) do AQUAREL, com o modo VVIR. Os níveis de NT-proBNP aumentaram signifi cativamente com a estimulação no modoVVIR (p < 0,001). Conclusão: Após três meses de estimulação com omodo VVIR, houve piora da QV dos pacientes chagásicos e aumento dos níveis de NT-proBNP (registro de ensaio clínico: ReBEc RBR-53x476)

Impact of DDD and VVIR Stimulation Modes on Functional Capacity and Quality of Life of Chagasic Patients

Introduction: Atrioventricular stimulation provides hemodynamic benefits over the isolated ventricular rate, but this advantage is not completely established in chagasic patients with systolic dysfunction. Objectives: To evaluate the influence of DDD and VVIR stimulation modes on functional capacity, quality of life (QoL) and laboratory abnormalities of a natriuretic peptide in chagasic patients with ventricular dysfunction submitted to pacemaker implantation. Methods: Twenty patients (55% male) with a mean age of 62.7 (± 9.9 years) and a mean ejection fraction of 41.8% (± 2.8) were prospectively studied. Alternately, patients received pacing in the DDD and VVIR modes for a period of three months under each schedule. The minimum percentage of ventricular pacing was 80%. After each period, the patient was submitted to the six-minute walk test (6MWT), QOL assessment by the Minnesota Living with Heart Failure Questionnaire (MLHFQ) and the Assay of QUAlity of life and RELated events (AQUAREL). Laboratory evaluation was performed with the N-terminal fraction of the brain natriuretic peptide (N-terminal pro b-type natriuretic peptide - NT-proBNP). Results: The mean distance walked on the 6MWT in the DDD and VVIR modes were 390.60 (± 52.71) and 396.30 (± 52.71) meters respectively (p = 0.160). Results of lower QOL were found, considering the physical domain of the MLHFQ (p = 0.03) and the domains of effort dyspnea (p = 0.05) and arrhythmia (p <0.001) of the AQUAREL with the VVIR mode. NT-proBNP levels increased significantly with stimulation in VVIR mode (p < 0.001). Conclusion: After three months of stimulation with the VVIR mode, there was worsening of the QoL of the chagasic patients and increase of the levels of NT-proBNP (clinical trial record: ReBEc RBR-53x476).

Role of cardiac pacing in congenital complete heart block

INTRODUCTION

Congenital complete heart block affects 1/15,000 live-born infants, predominantly due to atrioventricular nodal injury from maternal antibodies of mothers with systemic lupus erythermatosus or Sjogren's syndrome. The majority of these children will need a pacemaker implanted prior to becoming young adults. This article will review the various patient and technical factors that influence the type of pacemaker implanted, and the current literature on optimal pacing practices. Areas covered: A literature search was performed using PubMed, Embase and Web of Science. Data regarding epicardial versus transvenous implants, pacing-induced ventricular dysfunction, alternative pacing strategies (including biventricular pacing, left ventricular pacing, and His bundle pacing), and complications with pacemakers in the pediatric population were reviewed. Expert commentary: There are numerous pacing strategies available to children with congenital complete heart block. The risks and benefits of the initial implant should be weighed against the long-term issues inherent with a life-time of pacing.

Effects of right ventricular pacing sites on blood pressure variation in upright posture: a comparison of septal vs. apical pacing sites

AIMS

Large variations in blood pressure (BP) in the upright position are a major cause of pacemaker syndrome, observed in up to 80% of patients paced non-physiologically at the right ventricular (RV) apex. We hypothesized that the magnitude of BP variations might be influenced by the RV pacing site. To assess this, we compared haemodynamic findings during supine and upright posture with RV apical vs. septal pacing.

METHODS AND RESULTS

The study population comprised a retrospective cohort of 24 dual-chamber pacemaker patients with advanced or complete atrioventricular block, in which 11 were randomly chosen from those with RV apical pacing, and 13 randomly chosen from those with septal pacing. Studies were performed during fixed rate VVI and DDD pacing modes with patients in both supine and passive head-up tilt positions. Continuous BP, stroke volume, cardiac index, and total peripheral resistance index were measured non-invasively. During RV apical pacing, there were significant differences of beat-to-beat BP variation after movement from supine to upright posture for both VVI and DDD pacing modes (P < 0.05); however, this was not the case for either mode during RV septal pacing. Further, comparing RV apical to RV septal pacing in the supine position, there were no BP variation differences for either DDD or VVI modes. Conversely, in the upright position BP variation was significantly greater during RV apical vs. RV septal VVI pacing (P = 0.017) but not during DDD pacing.

CONCLUSION

During VVI pacing, RV septal pacing exhibited lesser BP variation during upright posture compared with RV apical pacing.

Effects of right ventricular septal versus apical pacing on plasma natriuretic peptide levels

Background:

To investigate the contribution of right ventricular (RV) pacing sites to the cardiac function, this study compares plasma B-type natriuretic peptide (BNP) levels during RV septal and apical pacing in patients implanted with a pacemaker.

Materials and Methods and Results:

Seventy-four consecutive patients with indication for permanent pacing were included. To provide for the possibility of appropriate subgroup analyses, patients were stratified according to their pacing mode into two groups: Those with dual chamber DDD(R)/VDD pacemakers (41 patients, mean age 54.1±18.4 years), and those with single chamber VVI pacemakers (33 patients, mean age 60.6±18.4 years). A prospective single-blinded randomized design was used. Randomization (1:1 way) was between lead placement on the RV septum or RV apex and occurred during the implant in both groups. Compared to baseline, a significant decrease in BNP (429.8±103 pg/ml and 291.7±138 pg/ml, respectively) levels was observed during DDD(R) /VDD pacing after two months. In contrast, during VVI (R) pacing, a significant increase in BNP levels was observed (657.5±104 pg/ml and 889.5±139 pg/ml, respectively). To determine the impact of pacing sites on cardiac function, we assessed the changes in BNP levels in each group separately. Despite the significant difference in the pattern of changes between the two groups (P < 0.02), no significant changes were observed within groups regarding the acute effect of the pacing site (RV apex vs. RV septal) on BNP levels (P=NS).

Conclusions:

Our main result showed no significant differences between pacing sites and concluded that hemodynamic improvement could be substantially influenced by pacing mode, more than by pacing site.