Impaired myocardial flow reserve on rubidium-82 positron emission tomography imaging predicts adverse outcomes in patients assessed for myocardial ischemia

J Am Coll Cardiol. 2011 Aug 9;58(7):740-8. doi: 10.1016/j.jacc.2011.01.065.


Objectives: We evaluated the prognostic value of myocardial flow reserve (MFR) using rubidium-82 ((82)Rb) positron emission tomography (PET) in patients assessed for ischemia.

Background: The clinical value of MFR quantification using (82)Rb PET beyond relative myocardial perfusion imaging remains uncertain.

Methods: We prospectively enrolled 704 consecutive patients; 677 (96%) completed follow-up (median 387 days [interquartile range: 375 to 416 days]). Patients were divided into 4 groups: I, normal summed stress score (SSS) (<4) and normal myocardial flow reserve (MFR) (>2); II, normal SSS and MFR <2; III, SSS ≥4 and MFR ≥2; IV, SSS ≥4 and MFR <2.

Results: For patients with a normal SSS and those with an abnormal SSS, there were significant differences in outcomes for hard events (cardiac death and myocardial infarction) between patients with MFR ≥2 and those with MFR <2 (I: 1.3% vs. II: 2% [p = 0.029]; III: 1.1% vs. IV: 11.4% [p = 0.05]) and for major adverse cardiac events (MACE) (p = 0.003 and p < 0.001, respectively). In the adjusted Cox model, MFR was an independent predictor of hard events (hazard ratio: 3.3; 95% confidence interval: 1.1 to 9.5; p = 0.029) and MACE (hazard ratio: 2.4, 95% confidence interval: 1.4 to 4.4, p = 0.003). The incremental prognostic value of the MFR over the SSS was demonstrated by comparing the adjusted SSS model with and without the MFR for hard events (p = 0.0197) and MACE (p = 0.002).

Conclusions: MFR quantified using (82)Rb PET predicts hard cardiac events and MACE independent of the SSS and other parameters. Routine assessment of (82)Rb PET-quantified MFR could improve risk stratification for patients being investigated for ischemia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Death
  • Dipyridamole
  • Electrocardiography
  • Exercise Test
  • Female
  • Fractional Flow Reserve, Myocardial*
  • Humans
  • Male
  • Middle Aged
  • Myocardial Infarction / etiology
  • Myocardial Infarction / physiopathology
  • Myocardial Ischemia / complications
  • Myocardial Ischemia / diagnostic imaging*
  • Myocardial Ischemia / physiopathology
  • Myocardial Perfusion Imaging
  • Positron-Emission Tomography*
  • Prognosis
  • Radiopharmaceuticals*
  • Rubidium Radioisotopes*
  • Vasodilator Agents


  • Radiopharmaceuticals
  • Rubidium Radioisotopes
  • Vasodilator Agents
  • Dipyridamole