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Is chronotropic incompetence a limitation in the evaluation of myocardial ischemia and prognosis?

Andrea De Lorenzo1, Gabriel Oliveira, Ana C Ramos

  • 1Diagnostic Imaging Clinic (CDPI), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.

Coronary Artery Disease
|November 22, 2013
PubMed

Insights

Chronotropic incompetence (CI) is linked to more severe myocardial ischemia and worse patient outcomes. Myocardial perfusion imaging (MPI) remains valuable for assessing heart health even with CI.

Area of Science:

  • Cardiology
  • Nuclear Medicine
  • Diagnostic Imaging

Background:

  • Chronotropic incompetence (CI) is the inability to achieve 85% of maximal predicted heart rate during exercise.
  • Assessing myocardial ischemia and prognosis in patients with CI using myocardial perfusion imaging (MPI) requires further investigation.

Purpose of the Study:

  • To evaluate the impact of chronotropic incompetence (CI) on myocardial ischemia assessment and prognosis in patients undergoing myocardial perfusion single-photon emission computed tomography (MPS).

Main Methods:

  • Exercise/rest MPS was performed on 391 patients, excluding those on negative chronotropic drugs.
  • Summed stress, rest, and difference scores (SSS, SRS, SDS) were calculated.
  • Patients were followed for hard events (death, myocardial infarction) or revascularization.

Main Results:

  • 11.5% of patients had CI, with higher perfusion scores (SSS, SRS, SDS) compared to those without CI.
  • History of myocardial infarction and SDS were independent predictors of CI.
  • Patients with CI experienced higher rates of hard events (12.5% vs 0.9%) and revascularization (20.0% vs 8.1%) than those without CI.

Conclusions:

  • CI is associated with significant myocardial ischemia.
  • Patients with CI exhibit poorer clinical outcomes, including higher rates of hard events and revascularization.
  • MPI retains diagnostic and prognostic value in patients with CI.
Abstract

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