Objective: To review the relevant literature on use of atrioventricular node ablation and pacing in patients with heart failure atrial fibrillation. Methods: APubMed/MEDLINE SCOPUS search was performed order to assess clinical outcomes pacemaker implantation, as well complications that may occur. Results: Several trials, observational analyses meta-analyses have shown “pace ablate” strategy not...

OBJECTIVE I(f), encoded by the hyperpolarization-activated, cyclic nucleotide-modulated (HCN) channel gene family, modulates cardiac pacing. During cardiac pacing, changes in membrane potential are rapid, preventing the very slow HCN channels from reaching equilibrium. Here, we examined the properties of HCN channels under non-equilibrium conditions to shed insight into how different HCN isofor...

Renal function and systemic hemodynamics were studied during rapid atrial pacing in dogs with complete heart block and in control dogs with normal atrioventricular conduction. Rapid atrial pacing in dogs with complete heart block produced no significant change in urine flow, sodium excretion, or systemic hemodynamics. In contrast, rapid cardiac pacing in control dogs produced progressive increa...

In this issue of iJACC (JACC: Cardiovascular Imaging), Botvinick et al. (1) perform a complex study involving the performance of equilibrium radionuclide myocardiography with phase analysis during ventricular tachycardia. The authors identify specific characteristics that define tolerability of the arrhythmia in individual patients. Most of these discriminating factors in the 2 patient groups i...

BACKGROUND The purpose of this article is to critically review the data accumulated to date from studies evaluating the hemodynamic and clinical effects of right ventricular apical pacing during conventional permanent cardiac pacing. The data from studies comparing the effects of right ventricular apical pacing and alternate site ventricular pacing are also reviewed. METHODS We conducted a ME...

The relative hemodynamic effects of heart rate, inotropic state, and atrioventricular (AV) synchrony during ventricular pacing were evaluated in 10 patients with normal left ventricular ejection fraction (LVEF) (0.66 +/- 0.07, mean S.D.) and in eight patients with a diminished LVEF (0.34 +/- 0.18). Hemodynamics were measured at AV intervals of 130, 0, and -130 msec during ventricular pacing at ...

BACKGROUND Whether right ventricular outfow tract septum (RVOTS) pacing is superior to right ventricular apex (RVA) pacing with respect to left ventricular synchrony, cardiac function, and remodelling in the elderly with normal left ventricular ejection fraction (LVEF), is still unknown. AIM To assess the impact of RVOTS vs. RVA pacing on the cardiac performance of the elderly with normal LVE...

BACKGROUND Cardiac "memory" refers to changes in T wave polarity induced by ventricular pacing that persist long after resumption of normal atrioventricular conduction. METHODS AND RESULTS We studied the occurrence and mechanism of T wave changes in the open-chest anesthetized dog subjected to three discontinuous 20-minute periods of right ventricular pacing. ECG changes were recorded in the ...

BACKGROUND One of the reasons for patient nonresponse to cardiac resynchronization therapy is a suboptimal left ventricular (LV) pacing site. LV electric delay (Q-LV interval) has been indicated as a prognostic parameter of cardiac resynchronization therapy response. This study evaluates the LV delay for the optimization of the LV pacing site. METHODS AND RESULTS Thirty-two consecutive patien...