Resynchronization therapy optimization by intracardiac impedance.

Aims: For successful cardiac resynchronization therapy (CRT), an optimization of left ventricular (LV) lead position and stimulation timing is required. The feasibility of optimizing LV lead position, atrioventricular delay (AVd), and interventricular delay (VVd) in CRT using intracardiac impedance measurement was evaluated.

Methods And Results: Heart failure patients (n = 14, NYHA 13×III, 1×II, ejection fraction: 26 ± 6%, QRS: 165 ± 30 ms) were stimulated by AAI and biventricular (DDD-BiV) pacing in turn.

Intracardiac impedance monitors stroke volume in resynchronization therapy patients.

Aims: Monitoring of haemodynamic parameters or surrogate parameters of the left ventricle is especially important for patients under cardiac resynchronization therapy (CRT). Intracardiac impedance reflects left ventricular (LV) volume changes well in animal models. Since it is unknown whether this also holds in humans with heart failure (HF), we examined the correlation of LV intracardiac impedance with haemodynamic parameters in CRT patients for different positions of the LV lead.

Assessing acute ventricular volume changes by intracardiac impedance in a chronic heart failure animal model.

Background: Implantable device diagnostics may play an essential role in simplifying the care of heart failure patients by providing fundamental insights into their complex clinical patterns. Early recognition of heart failure progression by a continuous hemodynamic monitoring would allow for timely therapeutic interventions to prevent decompensation and hospitalization. In this study, the feasibility of assessing ventricular volume changes by implant-based measurements of intracardiac impedance was tested in a heart failure animal model.

Intracardiac impedance monitors hemodynamic deterioration in a chronic heart failure pig model.

Introduction: A large number of heart failure (HF) patients benefit from cardiac resynchronization therapy. Measurements of intrathoracic impedance (ITZ) by implantable devices correlate with intrathoracic fluid content and are used for monitoring lung edema formation in HF patients. However, intrathoracic fluid is only an indirect parameter of cardiac function.