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Generation of Murine Cardiac Pacemaker Cell Aggregates Based on ES-Cell-Programming in Combination with Myh6-Promoter-Selection
Published on: February 17, 2015
[Cardiac autonomic blockade in sinus disease and indication for a pacemaker]
C J Solórzano Martín1, G Delgado Caro, P Lugo Peña
1Departamento de Cardiología del Hospital de Especialidades, Centro Médico de Occidente, IMSS, Guadalajara, Jal.
Functional autonomic blockade revealed significant autonomic disturbances in sick sinus syndrome patients. Many patients with abnormal intrinsic heart rate showed prolonged sinoatrial conduction time and sinus nodal recovery time after blockade.
Area of Science:
- Cardiology
- Autonomic Nervous System Physiology
Context:
- Sick sinus syndrome (SSS) often presents with symptoms requiring pacemaker implantation.
- Assessing autonomic nervous system (ANS) function is crucial for SSS management.
- Standard electrocardiographic methods are used to evaluate sinus node function.
Purpose:
- To investigate the impact of functional autonomic blockade (FAB) on sinus node recovery time (SNRTC) and sinoatrial conduction time (SACT) in patients with symptomatic SSS.
- To determine if FAB can help differentiate patients who truly require permanent pacing.
Summary:
- Functional autonomic blockade (FAB) using metoprolol and atropine was performed on 23 symptomatic SSS patients indicated for pacing.
- Patients with abnormal intrinsic heart rate (IHR) more frequently exhibited prolonged SACT and SNRTC post-FAB (15/16) compared to those with normal IHR (2/7).
- FAB identified severe autonomic disturbances in 3/7 patients with normal IHR and 4/16 with abnormal IHR.
Impact:
- FAB can reveal significant extrinsic autonomic influences on sinus node function in SSS patients.
- Results suggest that indications for permanent pacing in SSS should focus on intrinsic sinus node disease and symptomatic bradycardia with severe autonomic disturbances.
- This study refines criteria for pacemaker implantation in SSS, potentially reducing unnecessary procedures.
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