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Predictors of stroke in patients paced for sick sinus syndrome

Arnold J Greenspon1, Robert G Hart, David Dawson

  • 1Division of Cardiology, Jefferson Medical College and Thomas Jefferson University Hospital, Philadelphia, Pennsylvania 19107, USA. greenspon@jefferson.edu

Journal of the American College of Cardiology
|May 4, 2004
PubMed

Insights

In patients with sinus node dysfunction, clinical factors like prior stroke and hypertension, not pacing mode, predicted subsequent stroke. Atrial fibrillation after implantation also increased stroke risk in this group.

Area of Science:

  • Cardiology
  • Neurology
  • Clinical Trials

Background:

  • The impact of dual-chamber versus single-chamber ventricular pacing on stroke risk in sinus node dysfunction patients is unknown.
  • Sinus node dysfunction necessitates pacing, influencing cardiac function and potentially stroke risk.

Purpose of the Study:

  • To analyze factors associated with subsequent stroke in patients with sinus node dysfunction undergoing pacing.
  • To compare stroke incidence between dual-chamber and single-chamber ventricular pacing modes.

Main Methods:

  • Analysis of data from the prospective Mode Selection Trial (MOST) involving 2,010 patients with sinus node dysfunction.
  • Randomization to ventricular or dual-chamber pacing, with a median follow-up of 33.1 months.
  • Life-table analysis and multivariable regression to identify stroke predictors.

Main Results:

  • A total of 90 strokes occurred over 5,664 patient-years; stroke rates at 1 and 4 years were 2.2% and 5.8%, respectively.
  • No significant difference in stroke incidence was observed between dual-chamber (4%) and ventricular-paced (4.9%) groups (HR 0.82, p=0.36).
  • Significant stroke predictors included prior stroke/TIA, Caucasian race, hypertension, prior embolism, and NYHA class III/IV. Atrial fibrillation post-implantation was also a risk factor (HR 1.68).

Conclusions:

  • Clinical characteristics, rather than the mode of pacing, were independently associated with subsequent stroke risk.
  • Pacing mode did not significantly influence stroke occurrence in this patient cohort.
  • Identifying and managing clinical risk factors is crucial for stroke prevention in paced patients with sinus node dysfunction.
Abstract

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