Ambulatory blood pressure and assessment of pacemaker function

Area of Science:

• Cardiology
• Biomedical Engineering
• Physiology

Background:

• Sick sinus syndrome often necessitates pacemaker implantation.
• Ventricular pacing (VVI) can lead to hemodynamic compromise.
• Baroreflex sensitivity plays a crucial role in blood pressure regulation.

Purpose of the Study:

• To investigate the hemodynamic effects of VVI pacing in sick sinus syndrome patients.
• To determine the relationship between baroreflex response and symptomatic hypotension.
• To evaluate the efficacy of atrioventricular pacing (DVI) in alleviating pacing-induced symptoms.

Main Methods:

• Ambulatory blood pressure and electrocardiographic monitoring in 10 VVI pacemaker patients.
• Comparison between symptomatic and asymptomatic patients.
• Assessment of hemodynamic changes before and after pacemaker mode conversion to DVI in select patients.

Main Results:

• VVI pacing induced a significant fall in arterial blood pressure in all patients, more pronounced in those with symptoms.
• Symptomatic patients exhibited delayed blood pressure recovery due to impaired baroreflex activation.
• Conversion to DVI pacing abolished symptoms and normalized hemodynamic responses.

Conclusions:

• Symptomatic hypotension following VVI pacing is linked to the baroreflex response rate.
• Dual-chamber pacing (DVI) effectively mitigates hypotension and associated symptoms.
• Optimizing pacemaker settings can improve patient outcomes and quality of life.