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A study comparing VVI and DDI pacing in elderly patients with carotid sinus syndrome

S J McIntosh1, J Lawson, R S Bexton

  • 1Cardiovascular Investigation Unit, Royal Victoria Infirmary, Newcastle upon Type, United Kingdom.

Heart (British Cardiac Society)
|June 1, 1997
PubMed

Insights

Single chamber ventricular demand (VVI) pacing is inadequate for elderly patients with carotid sinus syndrome, often causing symptomatic hypotension. Dual chamber pacing (DDI) is generally better tolerated, though optimal mode cannot be predicted pre-pacing.

Area of Science:

  • Cardiology
  • Geriatrics
  • Electrophysiology

Background:

  • Carotid sinus syndrome (CSS) can cause syncope and falls in elderly patients.
  • Cardiac pacing is a common treatment for symptomatic CSS.
  • The optimal pacemaker mode for CSS patients requires investigation.

Purpose of the Study:

  • To evaluate the adequacy of single chamber ventricular demand (VVI) pacing in elderly patients with CSS.
  • To compare VVI pacing with dual chamber pacing (DDI) in this population.

Main Methods:

  • Prospective, double-blind, randomized cross-over study.
  • 30 elderly patients (>60 years) with CSS underwent dual chamber pacemaker implantation.
  • Patients were randomized to three-month periods of VVI and DDI pacing.

Main Results:

  • 11 patients developed profound hypotension with VVI pacing versus 2 with DDI pacing during carotid sinus massage.
  • The 'pacemaker effect' (blood pressure drop) was significantly greater with VVI pacing.
  • Eleven patients could not tolerate VVI pacing and were withdrawn; no patient preferred VVI.

Conclusions:

  • Elderly patients with CSS are prone to symptomatic hypotension with VVI pacing.
  • DDI pacing appears better tolerated in this group.
  • Pre-pacing cardiovascular tests cannot reliably predict the optimal pacing mode for individual CSS patients.
Abstract

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