Right ventricular apex pacing can have deleterious effects. Our aims were to investigate how many patients referred for permanent pacing were suitable candidates for permanent His bundle pacing, and to determine the proportion in whom such pacing was successful. All cases of suprahisian block and most cases of infrahisian block (71.4%) were corrected by temporary His bundle pacing. However, per...

OBJECTIVE In our previous in vitro study mid-myocardial relative to epicardial pacing decreased transmural dispersion of depolarization (TDR) and prevented ventricular arrhythmia. We therefore hypothesized that in vivo mid-myocardial pacing in canines has a similar effect. METHODS AND RESULTS Using custom-made electrodes, monophasic action potentials were simultaneously recorded in vivo from ...

INTRODUCTION Right ventricular (RV) anodal capture (AC) has been reported in cardiac resynchronization therapy (CRT), when left ventricular (LV) pacing uses pseudobipolar (LV tip to RV proximal electrode) configuration. The aim of the study was to analyze the prevalence of AC and its implications for device programming. METHODS AND RESULTS When AC occurred, the resulting QRS morphology was ev...

OBJECTIVE To compare clinical and haemodynamic variables between left ventricular and biventricular pacing in patients with severe heart failure; and to analyse haemodynamic changes during daily life and maximum exercise during chronic left ventricular and biventricular pacing. DESIGN Prospective single blinded randomised study with crossover. SETTING University hospital (tertiary referral ...

AIMS Right ventricular (RV) pacing has been shown to be potentially detrimental to left ventricular function. In conventional dual-chamber pacing the position of the atrial lead could influence duration of the atrio-ventricular (AV) intervals, which is one of the variables that could be associated with an increased percentage of RV pacing. We wanted to see if lead placement at selected atrial s...

In 2003, Medina-Ravell et al. 1 published a study that suggested that biventricular pacing could be arrhythmogenic in a subset of patients because of the reversal of the normal endocardial-to-epicardial activation sequence by left-ventricular epicardial pacing. As epicardial action potentials are briefer than endocardial action potentials, transmural dispersion of the repolarization (TDR) is la...

The right ventricular (RV) apex has been used as the traditional pacing site since the development of transvenous pacing in 1959. Some studies suggest that pacing the RV apex may cause an “iatrogenic” left bundle branch block and remodeling of the left ventricle and is therefore harmful. In the past decade, the need for alternate site pacing became imperative and there have been a multitude of ...

BACKGROUND Recently, due to the detrimental effects on the ventricular function associated with right ventricular apical (RVA) pacing, right ventricular septal (RVS) pacing has become the preferred pacing method. However, the term RVS pacing refers to both right ventricular outflow-tract (RVOT) and mid-septal (RVMS) pacing, leading to a misinterpretation of the results of clinical studies. The ...