Serial, integrated, non-invasive mapping of electro-mechanical activation of the human heart under various pacing conditions.

The pathway of electrical- and subsequent mechanical activation of the human
heart is altered by implantation of a cardiac pacemaker. However, assessment
and analysis of these alterations have been challenging throughout the years.
Recent technological developments allow non-invasive mapping of both
electrical- and mechanical activation patterns of the human heart. Improved
insight in electrical activation and the accompanying hemodynamic response may
contribute to optimization of the quality of life (QOL) of pacing candidates
and improve pacing efficacy in general.

To perform a human study demonstrating a detailed analysis of electrical and
mechanical activation under different cardiac pacing conditions and to describe
the accompanying hemodynamic response.

Objectives:

To demonstrate non-invasive mapping electromechanical activation is reliable
and clinical applicable on a routine base.

To perform an integrated study on the electro-mechanical relationship under
normal and pathological conditions

Integration and interpretation may provide a roadmap to predict and improve
clinical effects of cardiac pacing.

To demonstrate the feasibility of monitoring and optimizing cardiac
resynchronization therapy (CRT) candidates with non-invasive arterial pulse
contour measurements (NAPCM).

To compare effectiveness of non-invasive arterial pulse contour measurements
(NAPCM) with conventional echocardiography derived parameters to improve
response to cardiac resynchronization therapy (CRT).

To assess the feasibility of cardiac MRI (CMR) for the detection of atrial
fibrosis.

Prospective, observational, multicenter, follow-up study. Study duration has
been defined as a maximum of two years.

Of participants a baseline cardiac MRI is required to provide detailed anatomy,
a prerequisite for correct interpretation of Body Surface Map technology. In
case an ablation is carried out following the EPS in patients suffering from
atrial fibrillation, an MRI scan with contrast will be repeated in order to
assess atrial scar tissue.

This diagnostic modality can cause nausea, headache or general discomfort,
especially in subjects suffering from claustrophobia. A contrast agent will be
used in order to perform late enhancement MR imaging. This contrast agent can
cause nausea or vomiting and is contra-indicated in patients with renal
failure. Patients participating in this study have to visit the outpatient
department more frequently than other patients with an implanted pacemaker.
They will be seen at six-month intervals during the study period instead of at
nine-month intervals for non-participants with a pacemaker (regular patients).