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Chronotropic incompetence in a young adult: case report and literature review

Philip J Gentlesk1, Thor T Markwood, J Edwin Atwood

  • 1Cardiology Service, Walter Reed Army Medical Center, Washington, DC 20307-5001, USA.

Chest
|January 14, 2004
PubMed

Insights

Chronotropic incompetence (CI) limits heart rate response to exertion. Rate-responsive pacing improved functional capacity in a patient with CI due to sinus node dysfunction.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Internal Medicine

Background:

  • Chronotropic incompetence (CI) is the inability of heart rate to increase sufficiently to meet metabolic demands during physical activity.
  • CI is often linked to sinus node dysfunction, atrial fibrillation, or underlying structural heart disease, potentially causing significant functional impairment.

Observation:

  • A case study involving a 34-year-old male patient diagnosed with chronotropic incompetence secondary to sinus node dysfunction was presented.
  • The patient experienced substantial limitations in functional capacity due to his condition.

Findings:

  • The patient demonstrated a significant improvement in his functional capacity following the implementation of rate-responsive pacing.
  • This intervention effectively addressed the limitations imposed by chronotropic incompetence.

Implications:

  • Therapeutic strategies for chronotropic incompetence should prioritize addressing the root cause.
  • Rate-responsive pacing is a viable consideration for symptomatic patients experiencing CI, offering a means to enhance functional capacity.
  • The long-term prognosis for individuals with CI is contingent upon the specific underlying etiology and the effectiveness of management.

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